MyD88/ERK/NFkB pathways and pro-inflammatory cytokines release in periodontal ligament stem cells stimulated by Porphyromonas gingivalis

How aging influences the gut-bone marrow axis and alters hematopoietic stem cell regulation

The gut microbiome has come to prominence across research disciplines, due to its influence on major biological systems within humans. Recently, a relationship between the gut microbiome and hematopoietic system has been identified and coined the gut-bone marrow axis. It is well established that the hematopoietic system and gut microbiome separately alter with age; however, the relationship between these changes and how these systems influence each other demands investigation. Since the hematopoietic system produces immune cells that help govern commensal bacteria, it is important to identify how the microbiome interacts with hematopoietic stem cells (HSCs). The gut microbiota has been shown to influence the development and outcomes of hematologic disorders, suggesting dysbiosis may influence the maintenance of HSCs with age. Short chain fatty acids (SCFAs), lactate, iron availability, tryptophan metabolites, bacterial extracellular vesicles, microbe associated molecular patterns (MAMPs), and toll-like receptor (TLR) signalling have been proposed as key mediators of communication across the gut-bone marrow axis and will be reviewed in this article within the context of aging.

Diosgenin prevents periodontitis by inhibiting inflammation and promoting osteogenic differentiation

Diosgenin, an essential dietary steroidal sapogenin, possess multiple pharmacological activities. This study aimed to assess the effects of diosgenin on periodontitis and elucidate the mechanisms. Lipopolysaccharide (LPS)-stimulated human periodontal ligament stem cells (hPDLCs) and a Porphyromonas gingivalis (P.g) plus ligation-induced animal model were used for in vitro and in vivo studies, respectively. Inflammatory responses, nuclear factor κ-B (NF-κB) signaling and osteogenesis-related markers were measured both in LPS-stimulated hPDLSCs and in gingival tissue of periodontitis rats. Treatment with diosgenin significantly inhibited the production of tumor necrosis factor α (TNF-α), interleukin (IL)-1β, and interleukin (IL)-6 and the activation of NF-κB pathway in LPS-stimulated hPDLSCs. Further, treatment with diosgenin enhanced the expression of osteoblast-related genes and increased the osteogenic differentiation capacity. Further, activation NF-κB pathway largely abolished the protective effects of diosgenin. Consistent with the in vitro studies, in vivo studies showed that administering diosgenin to periodontitis rats significantly lowered the levels of the TNF-α, IL-1β, and IL-6 and the inflammatory transcription factor NF-κB in gingival tissue. In addition, osteoblast-related genes were promoted. Diosgenin attenuates periodontitis by adjusting NF-κB signaling to inhibit inflammatory effects and promoting osteogenesis, suggesting diosgenin might be developed as a therapeutic strategy for treating periodontitis in the future.

Porphyromonas gingivalis triggers inflammation in hepatocyte depend on ferroptosis via activating the NF-κB signaling pathway

OBJECTIVE

Non-alcoholic fatty liver disease (NAFLD) is a clinicopathological syndrome characterized by excessive fat deposition in hepatocytes caused by non-alcoholic liver injury. Porphyromonas gingivalis (P.g) is the main pathogen causing periodontitis, which can aggravate the progression of NAFLD in our previously study. The objective of this study was to further investigate the pathogenesis and moleculer michanisma of NAFLD aggravated by P.g.

METHODS

A mouse model of NAFLD was established, and the changes of inflammatory factors and NF-κB signaling pathway in liver tissue and L-02 cells were analyzed by transcriptome sequencing, Western blot, IHC and RT-PCR. In addition, the NF-κB signaling pathway inhibitor QNZ and ferroptosis inhibitor Fer-1 were used to analyze the relationship between NF-κB signaling pathway and ferroptosis in vitro.

RESULTS

In vivo and in vitro experiments, P.g can induce liver inflammation and activate NF-κB signaling pathway. At the same time, P.g promotes ferroptosis and inflammation in L-02 in vitro. QNZ alleviates ferroptosis and inflammatory activation in L-02. Fer-1 can relieve the L-02 inflammation caused by P.g products.

CONCLUSION

Porphyromonas gingivalis can induce ferroptosis and inflammation in hepatocytes and further worsen liver lesions. The mechanism of ferroptosis in hepatocytes depends on NF-κB signaling pathway, which provides a new strategy for clinical treatment and prevention of NAFLD.

Extracellular adenosine triphosphate regulates inflammatory responses of periodontal ligament cells

BACKGROUND

Various stimuli, that is, mechanical stresses or inflammation, induce the release of adenosine triphosphate (ATP) by human periodontal ligament cells (HPDLCs). Extracellular adenosine triphosphate (eATP) affects HPDLCs' functions such as immunosuppressive action and inflammatory responses. Lipopolysaccharide (LPS) is the key factor involved in periodontal inflammation. However, the possible correlation and detailed mechanism of inflammation-mediated eATP by LPS and inflammatory cascade formation in HPDLCs is unclarified. This study aims to examine the role of eATP on the HPDLCs' responses concerning inflammatory actions after LPS treatment.

METHODS

HPDLCs were stimulated with Porphyromonas gingivalis LPS and polyinosinic:polycytidylic acid (poly I:C). The amount of ATP release was measured at different time points using a bioluminescence assay. HPDLCs were treated with eATP. The expression of pro-inflammatory and anti-inflammatory genes was determined. Specific P2X purinoreceptor 7 (P2X7) inhibitors (brilliant blue G [BBG] and KN62), a specific P2Y purinoreceptor 1 (P2Y1) inhibitors (MRS2179), calcium chelator (EGTA), protein kinase C (PKC) inhibitors, nuclear factor kappa-light-chain-enhancer of activated B cells (NF𝜅B) activation inhibitors, and cyclic adenosine monophosphate (cAMP)-dependent protein kinase A (PKA) inhibitors (H89 dihydrochloride) and activators (forskolin) were used to dissect the mechanism of eATP-induced HPDLCs' inflammatory responses.

RESULTS

LPS and poly I:C induced ATP release. A low concentration of eATP (50 µM) increased pro-inflammatory genes (COX2, IL1B, IL6, IL8, IL12, and TNFA), while a high concentration (500 µM) enhanced anti-inflammatory genes (IL4 and IL10). BBG, KN62, and NF𝜅B activation inhibitors impeded eATP-induced pro-inflammatory genes. MRS2179 and H89 markedly suppressed eATP-induced anti-inflammatory genes. Forskolin induced IL4 and IL10.

CONCLUSION

HPDLCs respond to LPS by releasing ATP. eATP has dose-dependent dual functions on HPDLCs' inflammatory responses via different pathways. As regulation of inflammation is important in regeneration, eATP may help to limit inflammation and trigger periodontal regeneration.

Prenyltransferase gene expression reveals an essential role of prenylation for the inflammatory response in human gingival fibroblasts

BACKGROUND

Prenyltrasferases (PTases) are a class of enzymes known to be responsible for promoting posttranslational modification at the carboxyl terminus of proteins containing a so-called CaaX-motif. The process is responsible for proper membrane localization and the appropriate function of several intracellular signaling proteins. Current research demonstrating the pathomechanistic importance of prenylation in inflammatory illnesses emphasizes the requirement to ascertain the differential expression of PT genes under inflammatory settings, particularly in periodontal disease.

METHODS

Telomerase-immortalized human gingival fibroblasts (HGF-hTert) were cultured and treated with either inhibitors of prenylation (PTI) lonafarnib, tipifarnib, zoledronic acid, or atorvastatin at concentrations of 10 μM in combination with or without 10 μg Porphyromonas gingivalis lipopolysaccharide (LPS) for 24 h. Prenyltransferase genes FNTB, FNTA, PGGT1B, RABGGTA, RABGGTB, and PTAR1 as well as inflammatory marker genes MMP1 and IL1B were detected using quantitative real-time polymerase chain reaction (RT-qPCR). Immunoblot and protein immunoassay were used to confirm the results on the protein level.

RESULTS

RT-qPCR experiments revealed significant upregulation of IL1B, MMP1, FNTA, and PGGT1B upon LPS treatment. PTase inhibitors caused significant downregulation of the inflammatory cytokine expression. Interestingly, FNTB expression was significantly upregulated in response to any PTase inhibitor in combination with LPS, but not upon LPS treatment only, indicating a vital role of protein farnesyltransferase in the proinflammatory signaling cascade.

CONCLUSIONS

In this study, distinct PTase gene expression patterns in pro-inflammatory signaling were discovered. Moreover, PTase inhibiting drugs ameliorated inflammatory mediator expression by a significant margin, indicating that prenylation is a major pre-requisite for innate immunity in periodontal cells.

Exploring the impact of oral bacteria remnants on stem cells from the Apical papilla: mineralization potential and inflammatory response

Introduction

Bacterial persistence is considered one of the main causal factors for regenerative endodontic treatment (RET) failure in immature permanent teeth. This interference is claimed to be caused by the interaction of bacteria that reside in the root canal with the stem cells that are one of the essentials for RET. The aim of the study was to investigate whether prolonged exposure of stem cells from the apical papilla (SCAP) to bacterial remnants of Fusobacterium nucleatum, Actinomyces gerensceriae, Slackia exigua, Enterococcus faecalis, Peptostreptococcaceae yurii, commonly found in infected traumatized root canals, and the probiotic bacteria Lactobacillus gasseri and Limosilactobacillus reuteri, can alter SCAP's inflammatory response and mineralization potential.

Methods

To assess the effect of bacterial remnants on SCAP, we used UV-C-inactivated bacteria (as cell wall-associated virulence factors) and bacterial DNA. Histochemical staining using Osteoimage Mineralization Assay and Alizarin Red analysis was performed to study SCAP mineralization, while inflammatory and osteo/odontogenic-related responses of SCAPs were assessed with Multiplex ELISA.

Results

We showed that mineralization promotion was greater with UV C-inactivated bacteria compared to bacterial DNA. Immunofluorescence analysis detected that the early mineralization marker alkaline phosphatase (ALP) was increased by the level of E. coli lipopolysaccharide (LPS) positive control in the case of UV-C-inactivated bacteria; meanwhile, DNA treatment decreased the level of ALP compared to the positive control. SCAP's secretome assessed with Multiplex ELISA showed the upregulation of pro-inflammatory factors IL-6, IL-8, GM-CSF, IL-1b, neurotrophic factor BDNF, and angiogenic factor VEGF, induced by UV-C-killed bacteria.

Discussion

The results suggest that long term stimulation (for 21 days) of SCAP with UV-C-inactivated bacteria stimulate their mineralization and inflammatory response, while DNA influence has no such effect, which opens up new ideas about the nature of RET failure.

PINK1-mediated mitophagy reduced inflammatory responses to Porphyromonas gingivalis in macrophages

OBJECTIVE

Mitochondria are strained by microbial stimuli in the periodontal niche. Damaged mitochondria are cleared by mitophagy. The purpose of the study was to explore whether mitophagy participated in the progress of periodontitis and whether activation of mitophagy can inhibit inflammatory responses to bacterial infection in macrophages.

METHODS

Mitophagy-related genes were measured in the healthy and inflamed human gingiva. Bone marrow-derived macrophages (BMDMs) were infected with Porphyromonas gingivalis. Dexmedetomidine, urolithin A, and resveratrol were used to activate mitophagy, while small interference RNA was utilized to knock down PTEN-induced putative protein kinase 1 (PINK1). Activation of mitophagy-related genes and colocalization of them were detected by Western blot and confocal imaging. Damages of mitochondria, accumulation of mitochondrial reactive oxygen species (mtROS), and production of IL-1β, IL-6, and TNF-α were measured.

RESULTS

Levels of mitophagy-related genes were decreased in inflamed periodontal tissues and P. gingivalis-infected BMDMs. Dexmedetomidine, urolithin A, and resveratrol activated mitophagy, leading to reduced mitochondria damages, decreased mtROS generation, and inhibited IL-1β, IL-6, and TNF-α production. PINK1 knockdown reduced dexmedetomidine, urolithin A, and resveratrol-induced anti-inflammatory effect.

CONCLUSION

Inhibited mitophagy participated in the progress of periodontitis. Activation of mitophagy may become a therapeutic target during the progress of periodontitis by reducing mtROS.

In Vitro Anticancer Activity of Methanolic Extract of Justicia adhatoda Leaves with Special Emphasis on Human Breast Cancer Cell Line

Natural products are being targeted as alternative anticancer agents due to their non-toxic and safe nature. The present study was conducted to explore the in vitro anticancer potential of Justicia adhatoda (J. adhatoda) leaf extract. The methanolic leaf extract was prepared, and the phytochemicals and antioxidant potential were determined by LCMS analysis and DPPH radical scavenging assay, respectively. A docking study performed with five major alkaloidal phytoconstituents showed that they had a good binding affinity towards the active site of NF-κB. Cell viability assay was carried out in five different cell lines, and the extract exhibited the highest cytotoxicity in MCF-7, a breast cancer cell line. Extract-treated cells showed a significant increase in nitric oxide and reactive oxygen species production. Cell cycle analysis showed an arrest in cell growth at the Sub-G0 phase. The extract successfully inhibited cell migration and colony formation and altered mitochondrial membrane potential. The activities of superoxide dismutase and glutathione were also found to decrease in a dose-dependent manner. The percentage of apoptotic cells was found to increase in a dose-dependent manner in MCF-7 cells. The expressions of caspase-3, Bax, and cleaved-PARP were increased in extract-treated cells. An increase in the expression of NF-κB was found in the cytoplasm in extract-treated cells. J. adhatoda leaf extract showed a potential anticancer effect in MCF-7 cells.

Mechanical Compression by Simulating Orthodontic Tooth Movement in an In Vitro Model Modulates Phosphorylation of AKT and MAPKs via TLR4 in Human Periodontal Ligament Cells

Mechanical compression simulating orthodontic tooth movement in in vitro models induces pro-inflammatory cytokine expression in periodontal ligament (PDL) cells. Our previous work shows that TLR4 is involved in this process. Here, primary PDL cells are isolated and characterized to better understand the cell signaling downstream of key molecules involved in the process of sterile inflammation via TLR4. The TLR4 monoclonal blocking antibody significantly reverses the upregulation of phospho-AKT, caused by compressive force, to levels comparable to controls by inhibition of TLR4. Phospho-ERK and phospho-p38 are also modulated in the short term via TLR4. Additionally, moderate compressive forces of 2 g/cm², a gold standard for static compressive mechanical stimulation, are not able to induce translocation of Nf-kB and phospho-ERK into the nucleus. Accordingly, we demonstrated for the first time that TLR4 is also one of the triggers for signal transduction under compressive force. The TLR4, one of the pattern recognition receptors, is involved through its specific molecular structures on damaged cells during mechanical stress. Our findings provide the basis for further research on TLR4 in the modulation of sterile inflammation during orthodontic therapy and periodontal remodeling.

Microbial-stem cell interactions in periodontal disease

Periodontitis is initiated by hyper-inflammatory responses in the periodontal tissues that generate dysbiotic ecological changes within the microbial communities. As a result, supportive tissues of the tooth are damaged and periodontal attachment is lost. Gingival recession, formation of periodontal pockets with the presence of bleeding, and often suppuration and/or tooth mobility are evident upon clinical examination. These changes may ultimately lead to tooth loss. Mesenchymal stem cells (MSCs) are implicated in controlling periodontal disease progression and have been shown to play a key role in periodontal tissue homeostasis and regeneration. Evidence shows that MSCs interact with subgingival microorganisms and their by-products and modulate the activity of immune cells by either paracrine mechanisms or direct cell-to-cell contact. The aim of this review is to reveal the interactions that take place between microbes and in particular periodontal pathogens and MSCs in order to understand the factors and mechanisms that modulate the regenerative capacity of periodontal tissues and the ability of the host to defend against putative pathogens. The clinical implications of these interactions in terms of anti-inflammatory and paracrine responses of MSCs, anti-microbial properties and alterations in function including their regenerative potential are critically discussed based on literature findings. In addition, future directions to design periodontal research models and study ex vivo the microbial-stem cell interactions are introduced.

Potential Anti-Inflammatory Effects of a New Lyophilized Formulation of the Conditioned Medium Derived from Periodontal Ligament Stem Cells

The mesenchymal stem cells’ (MSCs) secretome includes the bioactive molecules released in the conditioned medium (CM), such as soluble proteins, free nucleic acids, lipids and extracellular vesicles. The secretome is known to mediate some of the beneficial properties related to MSCs, such as anti-inflammatory, anti-apoptotic and regenerative capacities. In this work, we aim to evaluate the anti-inflammatory potential of a new lyophilized formulation of CM derived from human periodontal ligament stem cells (hPDLSCs). With this aim, we treat hPDLSCs with lipopolysaccharide (LPS) and test the anti-inflammatory potential of lyophilized CM (LYO) through the evaluation of wound closure, transcriptomic and immunofluorescence analysis. LPS treatment increased the expression of TLR4 and of genes involved in its signaling and in p38 and NF-κB activation, also increasing the expression of cytokines and chemokines. Interestingly, LYO downregulated the expression of genes involved in Toll-like receptor 4 (TLR-4), nuclear factor kappa light chain enhancer of activated B cells (NF-κB) and p38 signaling. As a consequence, the genes encoding for cytokines and chemokines were also downregulated. Immunofluorescence acquisitions confirmed the downregulation of TLR-4 and NF-κB with the LYO treatment. Moreover, the LYO treatment also increased hPDLSCs’ migration. LYO was demonstrated to contain transforming growth factor (TGF)-β3 and vascular endothelial growth factor (VEGF). These results suggest that LYO represents an efficacious formulation with anti-inflammatory potential and highlights lyophilization as a valid method to produce stable formulations of MSCs’ secretome.

Erythropoietin regulates signaling pathways associated with neuroprotective events

Erythropoietin is a cytokine that binds to the Erythropoietin receptor and regulates the formation of erythroid cells during erythropoiesis in the bone marrow. However, many other organs and tissues express Erythropoietin and its receptor, such as the Nervous System, which principally regulates tissue protection. In the Central Nervous System, Erythropoietin is principally expressed by astrocytes, while neurons mainly express Erythropoietin receptors. Moreover, Erythropoietin acts as a pleiotropic molecule with neuroprotective effects, and its mechanisms of signal transduction pathways are defined, and there is a growing interest in its therapeutic potential. This review focuses on the role of Erythropoietin and its relationship with HIF1, PI3/Akt, GSK3B, JAK/STAT, and MAPKs signaling pathways that leads to cell survival after injury in the Central Nervous System. Knowledge of these signaling systems comprehensively could better guide EPO treatment to restoring different SNC alterations mediated by different insults.

Pharmacological Mechanisms of Shangke Huangshui against Skin and Soft Tissue Infection

Background

Skin and soft tissue infections (SSTIs) are a group of common diseases, usually caused by bacteria. Shangke Huangshui (SK) has been widely used to treat various SSTIs diseases for many years, but its mechanism is unclear. Therefore, this study was designed to investigate the anti-infective effect of SK on different skin and soft tissue infection diseases and to explore its underlying mechanism.

Methods

The subcutaneous abscess mouse model, the dermal ulcer rat model, and the infectious soft tissue injury rat model were established by injection of Staphylococcus aureus to evaluate the anti-inflammatory and antibacterial effects of SK. Abscess volume, local appearance score and histological changes, bacterial contents, and hydroxyproline concentration in the skin or soft tissue were analyzed. The levels of NO, TNF-α, IL-1β, and IL-8 in the serum and tissue were determined by ELISA method. The mRNA expression levels of TLR2, MyD88, TAK1, NF-κB, AP-1, and other genes were measured with qRT-PCR method, and the protein expression of TLR2, MyD88, TAK1, NF-κB, and AP-1 was detected by western blot method.

Results

SK had an obvious therapeutic effect on skin and soft tissue infections. It reduced the volume of abscess and promoted the healing of skin ulcer, improved pathological phenomena, such as inflammatory infiltration of skin and soft tissue, reduced the levels of white blood cells and NO in the blood, decreased bacteria contents in the skin and soft tissue. Furthermore, SK decreased the mRNA expression of TLR2, MyD88, TAK1, NF-κB and AP-1, and other related genes and also downregulated the protein expression of TLR2, MyD88, TAK1, NF-κB, and AP-1.

Conclusion

The experiments provide evidence that SK can treat skin and soft tissue infection diseases based on its comprehensive antibacterial and anti-inflammatory effects. The therapeutic mechanism may be associated with the inhibition of TLR2/MyD88/NF-κB signaling pathway.

Toll-Like Receptors and Dental Mesenchymal Stromal Cells

Dental mesenchymal stromal cells (MSCs) are a promising tool for clinical application in and beyond dentistry. These cells possess multilineage differentiation potential and immunomodulatory properties. Due to their localization in the oral cavity, these cells could sometimes be exposed to different bacteria and viruses. Dental MSCs express various Toll-like receptors (TLRs), and therefore, they can recognize different microorganisms. The engagement of TLRs in dental MSCs by various ligands might change their properties and function. The differentiation capacity of dental MSCs might be either inhibited or enhanced by TLRs ligands depending on their nature and concentrations. Activation of TLR signaling in dental MSCs induces the production of proinflammatory mediators. Additionally, TLR ligands alter the immunomodulatory ability of dental MSCs, but this aspect is still poorly explored. Understanding the role of TLR signaling in dental MSCs physiology is essential to assess their role in oral homeostasis, inflammatory diseases, and tissue regeneration.

A Levee to the Flood: Pre-injury Neuroinflammation and Immune Stress Influence Traumatic Brain Injury Outcome

Increasing evidence demonstrates that aging influences the brain's response to traumatic brain injury (TBI), setting the stage for neurodegenerative pathology like Alzheimer's disease (AD). This topic is often dominated by discussions of post-injury aging and inflammation, which can diminish the consideration of those same factors before TBI. In fact, pre-TBI aging and inflammation may be just as critical in mediating outcomes. For example, elderly individuals suffer from the highest rates of TBI of all severities. Additionally, pre-injury immune challenges or stressors may alter pathology and outcome independent of age. The inflammatory response to TBI is malleable and influenced by previous, coincident, and subsequent immune insults. Therefore, pre-existing conditions that elicit or include an inflammatory response could substantially influence the brain's ability to respond to traumatic injury and ultimately affect chronic outcome. The purpose of this review is to detail how age-related cellular and molecular changes, as well as genetic risk variants for AD affect the neuroinflammatory response to TBI. First, we will review the sources and pathology of neuroinflammation following TBI. Then, we will highlight the significance of age-related, endogenous sources of inflammation, including changes in cytokine expression, reactive oxygen species processing, and mitochondrial function. Heightened focus is placed on the mitochondria as an integral link between inflammation and various genetic risk factors for AD. Together, this review will compile current clinical and experimental research to highlight how pre-existing inflammatory changes associated with infection and stress, aging, and genetic risk factors can alter response to TBI.

The Th17/Treg cell balance: crosstalk among the immune system, bone and microbes in periodontitis

Periodontopathic bacteria constantly stimulate the host, which causes an immune response, leading to host-induced periodontal tissue damage. The complex interaction and imbalance between Th17 and Treg cells may be critical in the pathogenesis of periodontitis. Furthermore, the RANKL/RANK/OPG system plays a significant role in periodontitis bone metabolism, and its relationship with the Th17/Treg cell imbalance may be a bridge between periodontal bone metabolism and the immune system. This article reviews the literature related to the Th17/Treg cell imbalance mediated by pathogenic periodontal microbes, and its mechanism involving RANKL/RANK/OPG in periodontitis bone metabolism, in an effort to provide new ideas for the study of the immunopathological mechanism of periodontitis.

The Effect of Diabetes Mellitus on IGF Axis and Stem Cell Mediated Regeneration of the Periodontium

Periodontitis and diabetes mellitus (DM) are two of the most common and challenging health problems worldwide and they affect each other mutually and adversely. Current periodontal therapies have unpredictable outcome in diabetic patients. Periodontal tissue engineering is a challenging but promising approach that aims at restoring periodontal tissues using one or all of the following: stem cells, signalling molecules and scaffolds. Mesenchymal stem cells (MSCs) and insulin-like growth factor (IGF) represent ideal examples of stem cells and signalling molecules. This review outlines the most recent updates in characterizing MSCs isolated from diabetics to fully understand why diabetics are more prone to periodontitis that theoretically reflect the impaired regenerative capabilities of their native stem cells. This characterisation is of utmost importance to enhance autologous stem cells based tissue regeneration in diabetic patients using both MSCs and members of IGF axis.

Effects of Upregulation of TNFAIP3 on Diabetic Neuropathic Pain in Mice

Globally, diabetes has assumed epidemic proportions with the neuropathic complications attributed to the malady emerging as a substantial burden on patients and society. DNP has greatly affected the daily life of patients, the effect of traditional treatment methods is not ideal, and it is easy to produce drug resistance. This work is aimed at scrutinizing the effect of upregulating the expression of TNFAIP3 on diabetic neuralgia in mice. This work entailed ascertaining the effects of TNFAIP3 on a murine DNP system. This inspired us to observe the analgesic effect via high expression of lentivirus-mediated TNFAIP3 by intrathecal injection in the animal model to explore its regulatory impacts, symptom relief, and mechanistic role in pain. The results displayed an attenuation of hind paw pain hypersensitivity by LV-TNFAIP3 in the animals. The spinal cord and dorsal root ganglion of mice with neuropathic pain displayed an evident dip in TNFAIP3. Inhibition of the ERK/NF-κB signaling pathway employing LV-TNFAIP3 conspicuously suppressed this pathway while the diabetic pain hypersensitivity was quelled. This effect was also seen with insulin treatment evidently. In conclusion, according to the above analyses, the interaction between DNP and extracellular signal-regulated kinase signal transduction pathway is one of the key factors of pathogenesis.

IL-38 and IL-36 Target Autophagy for Regulating Synoviocyte Proliferation, Migration, and Invasion in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease leading to severe joint damage and disability. Fibroblast-like synoviocytes (FLSs) mostly contribute to the joint inflammation and destruction in RA through distinct mechanisms. However, little is known about newly discovered interleukin- (IL-) 36 and IL-38 involving in the pathology of RA. Here, we assessed the effect of IL-36 and IL-38 on RA-FLS function using IL-36 and IL-38 overexpression plasmids. We found that IL-36 inhibited synoviocytes proliferation while IL-38 showed an opposite influence. Furthermore, IL-36 and IL-38 significantly sequestered or accelerated RA-FLS migration and invasion capacity, respectively. Mechanically, IL-36 and IL-38 targeted autophagy for RA-FLS modulation. Using autophagy inhibitor 3-MA and inducer compound rapamycin, we found that autophagy negatively regulated the survival, migration, and invasion of synovial cells. Based on these results, IL-38 in combination with autophagy inhibitor 3-MA treatment demonstrated the strongest blockage of the above three activities of RA-FLS, and IL-38 overexpression reversed rapamycin-inhibited cell proliferation, migration, and invasion. Moreover, injection of IL-36 can improve the symptoms of RA in a rat model of RA. Taken together, we conclude that IL-38 and IL-36 target autophagy for regulating synoviocyte proliferation, migration, and invasion in RA.

The Effect of Liposomal Curcumin as an Anti-Inflammatory Strategy on Lipopolysaccharide e from Porphyromonas gingivalis Treated Endothelial Committed Neural Crest Derived Stem Cells: Morphological and Molecular Mechanisms

Curcumin, a yellow polyphenol extracted from the turmeric root is used as a diet supplement. It exhibits anti-inflammatory, antioxidant, and antitumor properties by modulating different intracellular mechanisms. Due to their low solubility in water, the curcumin molecules must be encapsulated into liposomes to improve the bioavailability and biomedical potential. For the periodontal tissue and systemic health, it is essential to regulate the local inflammatory response. In this study, the possible beneficial effect of liposomes loaded with curcumin (CurLIP) in neural crest-derived human periodontal ligament stem cells (hPDLSCs) and in endothelial-differentiated hPDLSCs (e-hPDLSCs) induced with an inflammatory stimulus (lipopolysaccharide obtained from Porphyromonas gingivalis, LPS-G) was evaluated. The CurLIP formulation exhibited a significant anti-inflammatory effect by the downregulation of Toll-like receptor-4 (TLR4)/Myeloid differentiation primary response 88 (MyD88)/nuclear factor kappa light chain enhancer of activated B cells (NFkB)/NLR Family Pyrin Domain Containing 3 (NLRP3)/Caspase-1/Interleukin (IL)-1β inflammation cascade and reactive oxygen species (ROS) formation. Moreover, the exposure to LPS-G caused significant alterations in the expression of epigenetic modifiers, such as DNA Methyltransferase 1 (DNMT1) and P300, while the CurLIP treatment showed physiological expression. Overall, our in vitro study provides novel mechanistic insights into the intracellular pathway exert by CurLIP in the regulation of inflammation and epigenetic modifications.

Anti-tumor effect of M2000 (β-d-mannuronic acid) on the expression of inflammatory molecules in the prostate cancer cell

Aim: The importance of chronic inflammation during the progression of prostate cancer (PCa) is well-known. M2000 (β-d-mannuronic acid) is a novel anti-inflammatory drug. According to its potential capacity for the inhibition of molecules involved in creating conditions of inflammation, it is reasonable to assess the anti-inflammatory role of M2000 in PCa cells.Methods: MTT assay was performed to determine the cytotoxicity of M2000 in PC3 cells. Correspondingly, these cells were cultured and then treated with low (25 µg/ml) and high (50 µg/ml) doses of M2000 as optimal doses. Thereafter, real-time RT-PCR, flow cytometry analysis, and zymography were performed to evaluate the expressions of MYD-88, NF-kB, IL-8, COX-2, MMP-2, and MMP-9 molecules. Results: Of note, the M2000 at the concentration of ≤200 μg/ml had no cytotoxicity effect on the cells. MYD-88 gene expression was significantly down-regulated at both low and high doses in the M2000-treated cells compared to the control (p = .017 and p = .001, respectively). The expression of the NF-kB was also reduced at both the gene and protein levels (all p values were <.001). The expression of IL-8 and COX-2 genes was also down-regulated in the high dose of M2000 (p<.001, p = .001, respectively). The decreased expression of the MMP-9 gene was observed at both doses (both p values were <.001).Conclusion: Inhibitory effects of M2000 on the activity of MMPs in the LPS/M2000-treated cells were evident, but not in the M2000-treated cells. M2000 as a new anti-inflammatory drug appears to constitute a potential agent for down-regulation of inflammatory molecules in the PCa cells.

Interleukin-18 in Brazilian Rheumatoid Arthritis Patients: Can Leflunomide Reduce It?

OBJECTIVES

Rheumatoid arthritis affects about 1% of the world's population. This is a chronic autoimmune disease. It is predominant in females with progressive joint damage. Immune cells are involved, especially Th1/Th17 lymphocytes and their inflammatory cytokines. These proteins have different functions in the immune system, such as IL-16 is a chemotactic factor; IL-18 can activate NFκB transcription producing inflammatory proteins; IL-31 can activate the JAK/STAT pathway which leads to the production of inflammatory factors in chronic diseases; IL-33 promotes IL-16 secretion which causes lymphocyte recruitment, and IL-32 and IL-34 appear to increase TNF secretion by macrophages activation in AR. The aim of this study was to evaluate serum levels of IL-16, IL-18, IL-31, IL-32, IL-33, and IL-34 and compare them with the severity and treatment of RA patients if there are any correlations.

METHODS

A total of 140 RA patients and 40 healthy donors were recruited from the Department of Rheumatology at Hospital das Clínicas from the Federal University of Pernambuco. 60 AR patients were naïve for any treatment. Serum cytokine levels were determined using an ELISA kit.

RESULTS

Serum IL-16 (p = 0.0491), IL-18 (p < 0.0001), IL-31 (p = 0.0004), and IL-32 (p = 0.0040) levels were significantly increased in RA patients compared with healthy donors. It was observed that patients using leflunomide had the lowest IL-18 levels, close to controls levels (p = 0.0064).

CONCLUSION

IL-16, IL-18, IL-31, and IL-32 are increased in the serum of RA patients. IL-18 is at lower levels in those AR who are taking leflunomide as treatment.

Insight into the roles of melatonin in bone tissue and bone‑related diseases (Review)

Bone‑related diseases comprise a large group of common diseases, including fractures, osteoporosis and osteoarthritis (OA), which affect a large number of individuals, particularly the elderly. The progressive destruction and loss of alveolar bone caused by periodontitis is a specific type of bone loss, which has a high incidence and markedly reduces the quality of life of patients. With the existing methods of prevention and treatment, the incidence and mortality of bone‑related diseases are still gradually increasing, creating a significant financial burden to societies worldwide. To prevent the occurrence of bone‑related diseases, delay their progression or reverse the injuries they cause, new alternative or complementary treatments need to be developed. Melatonin exerts numerous physiological effects, including inducing anti‑inflammatory and antioxidative functions, resetting circadian rhythms and promoting wound healing and tissue regeneration. Melatonin also participates in the health management of bone and cartilage. In the present review, the potential roles of melatonin in the pathogenesis and progression of bone injury, osteoporosis, OA and periodontitis are summarized. Furthermore, the high efficiency and diversity of the physiological regulatory effects of melatonin are highlighted and the potential benefits of the use of melatonin for the clinical prevention and treatment of bone‑related diseases are discussed.

Application of specialized pro-resolving mediators in periodontitis and peri-implantitis: a review

Scaling and root planning is a key element in the mechanical therapy used for the eradication of biofilm, which is the major etiological factor for periodontitis and peri‐implantitis. However, periodontitis is also a host mediated disease, therefore, removal of the biofilm without adjunctive therapy may not achieve the desired clinical outcome due to persistent activation of the innate and adaptive immune cells. Most recently, even the resident cells of the periodontium, including periodontal ligament fibroblasts, have been shown to produce several inflammatory factors in response to bacterial challenge. With increased understanding of the pathophysiology of periodontitis, more research is focusing on opposing excessive inflammation with specialized pro‐resolving mediators (SPMs). This review article covers the major limitations of current standards of care for periodontitis and peri‐implantitis, and it highlights recent advances and prospects of SPMs in the context of tissue reconstruction and regeneration. Here, we focus primarily on the role of SPMs in restoring tissue homeostasis after periodontal infection.

Ascorbic Acid: A New Player of Epigenetic Regulation in LPS-gingivalis Treated Human Periodontal Ligament Stem Cells

Periodontitis is usually sustained from microorganism of oral cavity, like Porphyromonas gingivalis (P. gingivalis). Periodontal disease is an infectious disease that afflicts a large number of people. Researches are investigating on the mesenchymal stem cells (MSCs) response to inflammatory events in combination with antioxidant substances. In particular, ascorbic acid (AA) increased cell proliferation, upregulated the cells pluripotency marker expression, provide a protection from inflammation, and induced the regeneration of periodontal ligament tissue. The purpose of the present research was to investigate the effects of AA in primary culture of human periodontal ligament stem cells (hPDLSCs) exposed to P. gingivalis lipopolysaccharide (LPS-G). The effect of AA on hPDLSCs exposed to LPS-G was determined through the cell proliferation assay. The molecules involved in the inflammatory pathway and epigenetic regulation have been identified using immunofluorescence and Western blot analyses. miR-210 level was quantified by qRT-PCR, and the ROS generation was finally studied. Cells co-treated with LPS-G and AA showed a restoration in terms of cell proliferation. The expression of NFκB, MyD88, and p300 was upregulated in LPS-G exposed cells, while the expression was attenuated in the co-treatment with AA. DNMT1 expression is attenuated in the cells exposed to the inflammatory stimulus. The level of miR-210 was reduced in stimulated cells, while the expression was evident in the hPDLSCs co-treated with LPS-G and AA. In conclusion, the AA could enhance a protective effect in in vitro periodontitis model, downregulating the inflammatory pathway and ROS generation and modulating the miR-210 level.

IL-1 Receptor Antagonist Protects the Osteogenesis Capability of Gingival-Derived Stem/Progenitor Cells under Inflammatory Microenvironment Induced by Porphyromonas gingivalis Lipopolysaccharides

Mesenchymal stem cells (MSCs) have been considered to be a future treatment option for periodontitis due to their excellent regenerative capability. However, it is still a challenge to protect MSCs' biological properties from multiple bacterial toxins in local inflammatory environment. The present study is aimed at investigating the treatment effect of interleukin-1 receptor antagonist (IL-1ra) on cell proliferation, migration, and osteogenic differentiation of gingival-derived mesenchymal stem cells (GMSCs) under an inflammatory microenvironment induced by Porphyromonas gingivalis lipopolysaccharides (P. gingivalis-LPS). GMSCs derived from Sprague-Dawley (SD) rats' free gingival tissues were treated with P. gingivalis-LPS (10 μg/mL) to create in vitro inflammatory environment. Different concentrations of IL-1ra (0.01-1 μg/mL) were used to antagonize the negative effect of LPS. Cell behaviors including proliferation, cloning formation unit (CFU), cell migration, osteogenic differentiation, mineral deposition, and cytokine production were assessed to investigate the protection effect of IL-1ra on GMSCs under inflammation. The toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) pathway activated by LPS was evaluated by real-time quantitative polymerase chain reaction (RT-PCR) and western blot. In response to P. gingivalis-LPS treatment, cell numbers, cloning formation rate, cell migration rate, proinflammatory cytokine production, and osteogenic differentiation-associated protein/mRNA expressions as well as mineralized nodules were suppressed in a time-dependent manner. These negative effects were effectively attenuated by IL-1ra administration in a time- and dose-dependent manner. In addition, mRNA expressions of TLR4 and IkBα decreased dramatically when IL-1ra was added into LPS-induced medium. IL-1ra also reversed the LPS-induced TLR4/NF-κB activation as indicated by western blot. The present study revealed that IL-1ra decreased inflammatory cytokine production in a supernatant, so as to protect GMSCs' osteogenesis capacity and other biological properties under P. gingivalis-LPS-induced inflammatory environment. This might be explained by IL-1ra downregulating TLR4-mediated NF-κB signaling pathway activation.

Tumor necrosis factor-α induces claudin-3 upregulation in kidney tubular epithelial cells through NF-κB and CREB1

Claudins are essential for tight junction formation and paracellular transport, and they affect key cellular events including proliferation and migration. The properties of tight junctions are dynamically modulated by a variety of inputs. We previously showed that the inflammatory cytokine tumor necrosis factor-α (TNFα), a major pathogenic factor in kidney disease, alters epithelial permeability by affecting the expression of claudin-1, -2, and -4 in kidney tubular cells. Here, we explored the effect of TNFα on claudin-3 (Cldn-3), a ubiquitous barrier-forming protein. We found that TNFα elevated Cldn-3 protein expression in tubular epithelial cells (LLC-PK1 and IMCD3) as early as 3 h post treatment. Bafilomycin A and bortezomib, inhibitors of lysosomal and proteasomes, respectively, reduced Cldn-3 degradation. However, TNFα caused a strong upregulation of Cldn-3 in the presence of bafilomycin, suggesting an effect independent from lysosomes. Blocking protein synthesis using cycloheximide prevented Cldn-3 upregulation by TNFα, verifying the contribution of de novo Cldn-3 synthesis. Indeed, TNFα elevated Cldn-3 mRNA levels at early time points. Using pharmacological inhibitors and siRNA-mediated silencing, we determined that the effect of TNFα on Cldn-3 was mediated by extracellular signal regulated kinase (ERK)-dependent activation of NF-κB and PKA-induced activation of CREB1. These two pathways were turned on by TNFα in parallel and both were required for the upregulation of Cldn-3. Because Cldn-3 was suggested to modulate cell migration and epithelial-mesenchymal transition (EMT), and TNFα was shown to affect these processes, Cldn-3 upregulation may modulate regeneration of the tubules following injury.

Super Activated Platelet Lysate, a Novel Autologous Platelet Lysate, Regulates the Expression of Inflammasome and Cytokine in the Experimental Periodontitis in Rats

Purpose

The aim of the present study was to evaluate the expression of inflammasome and cytokine on experimental periodontitis with super activated platelet lysate (SPL) in rats.

Methods

Periodontitis was induced by submerging cotton ligatures on the right side of the maxillary second molar in 36 Wistar rats. The rats were divided into 3 groups randomly: the rats received no treatment (control group); local injection with sterile saline (ligature+saline group) and local injection with SPL (ligature+SPL group). After treatments, the alveolar bone level and inflammation of periodontal tissue were evaluated by micro-computed tomography (micro-CT) scanning and histological examination, respectively. The expression of inflammasome and cytokine was evaluated by real-time quantitative polymerase chain reaction (RT-qPCR) assay.

Results

Compared with the control group, the bone loss significantly increased by 0.9 mm in the ligature+saline group and 0.4 mm in the ligature+SPL group (P < 0.001). 0.5 mm reduction in the bone loss was founded in the ligature+SPL group compared with the ligature+saline group (P < 0.001). The gene expression of CCL2, CXCL2, IL-6, IL-18, IL-1α, IL-1β, CXCL10, CXCL16, CCL5 was significantly reduced in the ligature+SPL group compared with the ligature+saline group (P < 0.05). Compared with the ligature+saline group, the expression for inflammasome NLRP3, AIM2, CASP1 was both downregulated in the ligature+SPL group (P < 0.05).

Conclusion

Our present study demonstrated local injection of SPL regulated the expression of inflammasome and cytokine and had a visible effect of relieving inflammation in the experimental periodontitis in rats.

Treatment with Luteolin Improves Lipopolysaccharide-Induced Periodontal Diseases in Rats

Periodontitis is a dental disease that produces the progressive destruction of the bone surrounding the tooth. Especially, lipopolysaccharide (LPS) is involved in the deterioration of the alveolar bone, inducing the release of pro-inflammatory mediators, which cause periodontal tissue inflammation. Luteolin (Lut), a molecule of natural origin present in a large variety of fruits and vegetables, possess beneficial properties for human health. On this basis, we investigated the anti-inflammatory properties of Lut in a model of periodontitis induced by LPS in rats. Animal model predicted a single intragingival injection of LPS (10 μg/μL) derived from Salmonella typhimurium. Lut administration, was performed daily at different doses (10, 30, and 100 mg/kg, orally), starting from 1 h after the injection of LPS. After 14 days, the animals were sacrificed, and their gums were processed for biochemical analysis and histological examinations. Results showed that Lut (30 and 100 mg/kg) was equally able to reduce alveolar bone loss, tissue damage, and neutrophilic infiltration. Moreover, Lut treatment reduced the concentration of collagen fibers, mast cells degranulation, and NF-κB activation, as well as the presence of pro-inflammatory enzymes and cytokines. Therefore, Lut implementation could represent valid support in the pharmacological strategy for periodontitis, thus improving the well-being of the oral cavity.

Hyperoside ameliorates periodontitis in rats by promoting osteogenic differentiation of BMSCs via activation of the NF-κB pathway

Hyperoside, as an active compound, widely exists in a large number of Chinese herbal medicines and has been reported to possess anti‐inflammatory and diuretic properties. However, the effects and underlying mechanisms of hyperoside on periodontitis have not been previously reported. In this study, we found that hyperoside ameliorates symptoms of periodontitis in a rat model, with improvements in alveolar bone resorption, relief of inflammatory infiltration, increase in orderly arrangement of collagen fibers and increase of osteogenic differentiation. In addition, hyperoside promoted proliferation, up‐regulated EdU‐positive cells, decreased cell‐cycle distribution and increased the protein expression of Ki67 and PCNA in rat bone mesenchymal stem cells (rBMSCs), as revealed by Cell Counting Kit‐8, EdU, flow cytometry and western blot analysis. Moreover, hyperoside significantly promoted osteogenic differentiation, as shown by quantitative RT‐PCR, western blot and alizarin red staining assays. Furthermore, hyperoside activated the nuclear factor‐κB (NF‐κB) signaling pathway in rBMSCs, similar to the results observed in vivo. Finally, BMS345541, an inhibitor of the NF‐κB signaling pathway, could reverse the effects of hyperoside on the biological functions in rBMSCs. In conclusion, our results suggest that hyperoside has potential therapeutic properties against periodontitis via promotion of proliferation and osteogenic differentiation of rBMSCs via activation of the NF‐κB signaling pathway.

Putative anti-inflammatory, antioxidant, and anti-apoptotic roles of the natural tissue guardian methyl palmitate against isoproterenol-induced myocardial injury in rats

Background

Myocardial injury is considered as a worldwide main cause of morbidity and mortality. The present study aimed to investigate the probable cardioprotective activity of the naturally occurring endogenous fatty acid ester methyl palmitate (MP) against isoproterenol (ISO)-induced myocardial injury in rats and the possible underlying molecular mechanisms. The study was carried out in two consecutive sets of experiments; the first set screened the cardioprotective dose of MP in ISO-intoxicated rats. In the second set, forty male Sprague Dawley rats received either MP (150 mg/kg, p.o) three times/week for 2 weeks and/or 2 consecutive doses of ISO separated by 24 h (85 mg/kg, s.c) on the 13th and 14th days. Different cardiotoxicity and oxidative stress markers were assessed. Furthermore, endothelial nitric oxide synthase (eNOS) levels were determined. For detection of apoptosis, Bax, Bcl-2, and caspase 3 were estimated. To assess inflammation, toll-like receptor 4 (TLR-4) and tumor necrosis factor-alpha (TNF-α) were measured using ELISA. Meanwhile, nuclear factor kappa B (NF-kB) and cyclooxygenase-2 (COX-2) were detected immunohistochemically.

Results

Pretreatment with MP significantly ameliorated the cardiotoxicity and oxidative stress markers. It also markedly elevated eNOS content, decreased apoptotic marker expression, and mitigated TLR-4 activation and other inflammatory markers. Electrocardiography and histopathological examination also confirmed the cardioprotective effect of MP.

Conclusion

The findings of this study indicated that MP possesses a potent cardioprotective activity against ISO-induced myocardial injury through its significant antioxidant, anti-apoptotic, anti-inflammatory, and vasodilatation activities.

Graphical abstract

Phyllanthus amarus prevents LPS-mediated BV2 microglial activation via MyD88 and NF-κB signaling pathways

BACKGROUND

Phyllanthus amarus has been shown to attenuate lipopolysaccharide (LPS)-induced peripheral inflammation but similar studies in the central nervous system are scarce. The aim of the present study was to investigate the neuroprotective effects of 80% ethanol extract of P. amarus (EPA) in LPS-activated BV2 microglial cells.

METHODS

BV2 microglial cells c for 24 h, pre-treated with EPA for 24 h prior to LPS induction for another 24 h. Surface expression of CD11b and CD40 on BV2 cells was analyzed by flow cytometry. ELISA was employed to measure the production of pro-inflammatory mediators i.e. nitric oxide (NO) and tumor necrosis factor (TNF)-α. Western blotting technique was used to determine the expression of inducible nitric oxide synthase (iNOS), myeloid differentiation protein 88 (MYD88), nuclear factor kappa B (NF-κB), caspase-1, and mitogen activated protein kinase (MAPK).

RESULTS

Qualitative and quantitative analyses of the EPA using a validated ultra-high pressure liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method indicated the presence of phyllanthin, hypophyllanthin, niranthin, ellagic acid, corilagin, gallic acid, phyltetralin, isolintetralin and geraniin. EPA suppressed the production of NO and TNFα in LPS-activated BV2 microglial cells. Moreover, EPA attenuated the expression of MyD88, NF-κB and MAPK (p-P38, p-JNK and p-ERK1/2). It also inhibited the expression of CD11b and CD40. EPA protected against LPS-induced microglial activation via MyD88 and NF-κB signaling in BV2 microglial cells.

CONCLUSIONS

EPA demonstrated neuroprotective effects against LPS-induced microglial cells activation through the inhibition of TNFα secretion, iNOS protein expression and subsequent NO production, inhibition of NF-κB and MAPKs mediated by adapter protein MyD88 and inhibition of microglial activation markers CD11b and CD40.

Odontogenic infection by Porphyromonas gingivalis exacerbates fibrosis in NASH via hepatic stellate cell activation

Odontogenic infection of Porphyromonas gingivalis (P.g.), a major periodontal pathogen, exacerbates pathological progression of non-alcoholic steatohepatitis (NASH). In this study, we aimed to clarify the detailed mechanism in which P.g. induced hepatic stellate cells (HSCs; key effector cells in liver fibrosis) activation. In the liver of high fat diet-induced NASH mouse model with P.g. odontogenic infection, immunolocalization of P.g. was detected. The number of hepatic crown-like structure, which was macrophage aggregation and related to liver fibrosis, was drastically increased and fibrosis area was also increased through upregulating immunoexpression of Phosphorylated Smad2 (key signaling molecule of TGF-β1) and Galectin-3. P.g.-secreted trypsin-like enzyme [gingipain; an activator of protease-activated receptor 2 (PAR2)] stimulated HSC proliferation and differentiation through Smad and ERK signaling induced by TGF-β1 produced from HSCs with P.g.-infection. Further, Galectin-3 produced from HSCs with P.g. infection and P.g.-derived LPS/lipoprotein stimulation stabilized TGFβ-receptor II resulting in increasing sensitivity for TGF-β1, finally leading to HSC differentiation via activating Smad and ERK signaling. In addition to them, hepatocytes (main component cells of liver) contributed to HSC activation through TGF-β1 and Galectin-3 production in paracrine manner. Collectively, P.g.-odontogenic infection exacerbates fibrosis of NASH by HSC activation through TGF-β1 and Gal-3 production from HSCs and hepatocytes.

Astragalus polysaccharides alleviates LPS-induced inflammation via the NF-κB/MAPK signaling pathway

Early weaning usually causes intestinal disorders, enteritis, and diarrhea in young animals and human infants. Astragalus polysaccharides (APS) possesses anti-inflammatory activity. To study the anti-inflammatory mechanisms of APS and its potential effects on intestinal health, we performed an RNA sequencing (RNA-seq) study in lipopolysaccharide (LPS)-stimulated porcine intestinal epithelial cells (IPEC-J2) in vitro. In addition, LPS-stimulated BALB/c mice were used to study the effects of APS on intestinal inflammation in vivo. The results from the RNA-seq analysis show that there were 107, 756, and 5 differentially expressed genes in the control versus LPS, LPS versus LPS+APS, and control versus LPS+APS comparison groups, respectively. The results of Kyoto Encyclopedia of Genes and Genomes enrichment analysis indicated that the mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling pathways play significant roles in the regulation of inflammatory factors and chemokine expression by APS. Further verification of the above two pathways by using western blot and immunofluorescence analysis revealed that the gene expression levels of the phosphorylated p38 MAPK, ERK1/2, and NF-κB p65 were inhibited by APS, while the expression of IκB-α protein was significantly increased (p < .05), indicating that APS inhibits the production of inflammatory factors and chemokines by the inhibition of activation of the MAPK and NF-κB inflammatory pathways induced by LPS stimulation. Animal experiments further demonstrated that prefeeding APS in BALB/c mice can alleviate the expression of the jejunal inflammatory factors interleukin 6 (IL-6), IL-Iβ, and tumor necrosis factor-α induced by LPS stimulation and improve jejunal villus morphology.

IFNγ receptor down-regulation facilitates Legionella survival in alveolar macrophages

Legionella pneumophila is an opportunistic human pathogen and causative agent of the acute pneumonia known as Legionnaire's disease. Upon inhalation, the bacteria replicate in alveolar macrophages (AM), within an intracellular vacuole termed the Legionella-containing vacuole. We recently found that, in vivo, IFNγ was required for optimal clearance of intracellular L. pneumophila by monocyte-derived cells (MC), but the cytokine did not appear to influence clearance by AM. Here, we report that during L. pneumophila lung infection, expression of the IFNγ receptor subunit 1 (IFNGR1) is down-regulated in AM and neutrophils, but not MC, offering a possible explanation for why AM are unable to effectively restrict L. pneumophila replication in vivo. To test this, we used mice that constitutively express IFNGR1 in AM and found that prevention of IFNGR1 down-regulation enhanced the ability of AM to restrict L. pneumophila intracellular replication. IFNGR1 down-regulation was independent of the type IV Dot/Icm secretion system of L. pneumophila indicating that bacterial effector proteins were not involved. In contrast to previous work, we found that signaling via type I IFN receptors was not required for IFNGR1 down-regulation in macrophages but rather that MyD88- or Trif- mediated NF-κB activation was required. This work has uncovered an alternative signaling pathway responsible for IFNGR1 down-regulation in macrophages during bacterial infection.

Lipoxin suppresses inflammation via the TLR4/MyD88/NF-κB pathway in periodontal ligament cells

Objective

The objective of the present study was to evaluate the anti‐inflammatory effects of lipoxin A4 (LXA4) for the treatment of periodontitis in an in vitro model.

Methods

Human PDLCs were challenged with Escherichia coli (E. coli) lipopolysaccharide (LPS) to evoke an inflammatory response. This was done either in monoculture or in coculture with THP‐1, a monocytic cell line. Thereafter, cytokine expression was measured by ELISA, with or without LXA4. In addition, the effects of LXA4 were analyzed on the TLR‐MyD88‐NF‐κB (TMN)‐mediated intracellular signal pathway using immunocytochemistry.

Results

In response to LPS, the level of the pro‐inflammatory cytokine tumor necrosis factor alpha increased, whereas the anti‐inflammatory cytokine interleukin‐4 decreased significantly (p < .05). These effects were consistently reversed when LPS‐challenged PDLCs were also treated with LXA4. The results in the coculture system were comparable to the monoculture. Immunohistochemistry and quantitative assessment confirmed the importance of the TMN signal pathway in these processes.

Conclusion

These results corroborate earlier findings that PDLCs play an important role in inflammation. Moreover, LXA4 might offer new approaches for the therapeutic treatment of periodontal disease.

Salvianolic Acid C Attenuates LPS-Induced Inflammation and Apoptosis in Human Periodontal Ligament Stem Cells via Toll-Like Receptors 4 (TLR4)/Nuclear Factor kappa B (NF-κB) Pathway

BACKGROUND Periodontitis is a chronic inflammatory disease that causes gingival detachment and disintegration of alveolar bone. Salvianolic acid C (SAC) is a polyphenol compound with anti-inflammatory and antioxidant activities that is isolated from Danshen, a traditional Chinese medicine made from the roots of Salvia miltiorrhiza Bunge. The aim of this study was to investigate the mechanisms of underlying its protective effects and its inhibition effect on inflammation and apoptosis in human periodontal ligament stem cells (hPDLSCs). MATERIAL AND METHODS LPS-induced hPDLSCs, as a model mimicking an inflammatory process of periodontitis in vivo, were established to investigate the therapeutic effect of SAC in periodontitis. The inflammatory cytokines secretion and oxidative stress status were measured by use of specific commercial test kits. The hPDLSCs viability was analyzed by Cell Counting Kit-8 assay. The cell apoptosis and cell cycle were assayed with flow cytometry. Expressions levels of proteins involved in apoptosis, osteogenic differentiation, and TLR4/NF-kappaB pathway were evaluated by Western blotting. Alkaline phosphatase (ALP) activity was detected by ALP assay kit and ALP staining. The mineralized nodules formation of hPDLSCs was checked by Alizarin Red S staining. RESULTS Our results showed that LPS induced increased levels of inflammatory cytokines and oxidative stress and mediated the phosphorylation and nuclear translocation of NF‑kappaB p65 in hPDLSCs. SAC reversed the abnormal secretion of inflammatory cytokines and inhibited the TLR4/NF‑kappaB activation induced by LPS. SAC also upregulated cell viability, ALP activity, and the ability of osteogenic differentiation. The anti-inflammation and TLR4/NF‑kappaB inhibition effects of SAC were reversed by TLR4 overexpression. CONCLUSIONS Taken together, our results revealed that SAC effectively attenuates LPS-induced inflammation and apoptosis via the TLR4/NF-kappaB pathway and that SAC is effective in treating periodontitis.

Escin protects against acetaminophen-induced liver injury in mice via attenuating inflammatory response and inhibiting ERK signaling pathway

Acetaminophen (APAP) overdose may lead to the formation of oxidative stress, hepatocyte apoptosis and necrosis, and, eventually result in acute liver failure. Escin, a major extracted component of Aesculus hippocastanum, reportedly exerts anti-inflammatory, anti-edematous and anti-oxidant properties. Previous studies have demonstrated these protective effects of A. hippocastanum extracts on ischemia/reperfusion intestinal injury and endotoxin-induced lung injury. In this study, we aimed to evaluate the effect of escin on APAP-induced liver injury in mice. Mice were intraperitoneally administrated with APAP (300 mg/kg) or an equal volume of saline (control), followed by a treatment with various concentrations of escin (0, 0.5, 1, 2 and 4 mg/kg) for 30 min. The animals were sacrificed 16 h following APAP administration for serum and liver tissue assay. Escin treatment attenuated the damage of APAP-induced liver injury in a dose-dependent manner (0.5-4 mg/kg). Escin also attenuated the hepatic myeloperoxidase (MPO) activity and hepatic pro-inflammatory cytokines (i.e., TNF-α, IL-1β, IL-6 and IL-17). Furthermore, escin treatment decreased the hepatic phosphorylation expression of extracellular signal-regulated kinase (ERK). Our data indicates that escin shows protective effects on APAP-induced hepatotoxicity in a dose-dependent manner through anti-inflammatory mechanism and the inhibition of ERK signaling pathway.

HEMA Effects on Autophagy Mechanism in Human Dental Pulp Stem Cells

Autophagy is a complex mechanism that permits the degradation of cellular components in order to enhance cell homeostasis, recycling the damaged, dysfunctional, or unnecessary components. In restorative dentistry practice, free resin monomers of 2-hydroxyethyl methacrylate (HEMA) can be released. The aim of this study was to investigate the effect of HEMA on proliferation and autophagy in human dental pulp stem cells (hDPSCs). Human DPSCs were treated with different concentrations of HEMA (3 and 5 mmol L⁻¹). To evaluate the proliferation rate, MTT and trypan blue assays were used. Autophagic markers such as microtubule-associated protein 1 light chain 3 (LC3-I/II) and ubiquitin-binding protein (p62) were analyzed through immunofluorescence observations. Beclin1, LC3-I/II, and p62 were evaluated by means of Western blotting detection. Considering that activity of extracellular signal–regulated kinase (ERK) and its phosphorylated form (pERK) mediates several cellular processes, such as apoptosis, autophagy, and senescence, the involvement of ERK/pERK signaling was also evaluated. Obtained results showed a decreased cell proliferation associated with morphological changes in HEMA-treated cells. The Western blot results showed that the expression levels of Beclin1, LC3-I/II, and ERK were significantly elevated in HEMA-treated cells and in cells co-treated with rapamycin, an autophagic promoter. The expression levels of p62 were significantly reduced compared to the untreated samples. Protein levels to the autophagic process, observed at confocal microscopy confirmed the data obtained from the Western blot. The up-regulation of ERK and pERK levels, associated with nuclear translocation, revealed that ERK pathway signaling could act as a promoter of autophagy in dental pulp stem cells treated with HEMA.

TNF-α mediated MEK-ERK signaling in invasion with putative network involving NF-κB and STAT-6: a new perspective in glioma

Glioblastoma is the most common malignant primary brain tumor with poor prognosis. Invasion involves pro-inflammatory cytokines and major signaling hubs. Tumor necrosis factor-α (TNF-α) acts as a master switch in establishing an intricate link between inflammation and cancer. The present study attempted to explore the possible implication of MAPK extracellular signaling-regulated kinase kinase (MEK)-extracellular signaling-regulated kinase (ERK) signaling pathway and expression of nuclear factor-κB (NF-κB), signal transducers and activators of transcription-6 (STAT-6), ERK, and phosphorylated-ERK (p-ERK) signaling proteins in TNF-α microenvironment. U0126 and PD98059 were used to inhibit the MEK-ERK1/2 pathway. TNF-α stimulation enhanced invasion in U87MG, U251MG and patient-derived primary glioma cells, whereas cell viability was not altered. Matrix metalloproteinase-2 (MMP-2) activity was increased only in U251MG glioma cells. These data suggest that TNF-α microenvironment plays an important role in the invasion of U251MG, U87MG, and patient-derived primary glioma cells, without any cytotoxic effect. The MMP-2 activity is differentially regulated by TNF-α stimulation in these cells. TNF-α stimulation upregulated the protein expression of ERK-1, ERK-2 and also increased the level of p-ERK1/2. TNF-α stimulation further upregulated the expression of NF-κB1, STAT-6 in tandem with Ras-MEK signaling system in U87MG cells, which emphasized the possible involvement of these signaling hubs in the glioma microenvironment. MEK-ERK inhibitors significantly attenuated the invasion of U87MG cells mediated by the TNF-α stimulation, probably through their inhibitory impact on p-ERK1/2 and ERK-2. This study provides the possible rationale of invasion by glioma cells in a TNF-α-induced pro-inflammatory milieu, which involves direct role of MEK-ERK signaling, with possible implication of NF-κB and STAT-6.

3D Human Periodontal Stem Cells and Endothelial Cells Promote Bone Development in Bovine Pericardium-Based Tissue Biomaterial

Bone defects repair represents a public and urgent problem in clinical practice, in fact, every year, more than two million patients required new treatments for bone injuries. Today a complete vascularization is strategic in bone formation, representing a new frontier for clinical application. Aim of this research has been developed a three-dimensional (3D) coculture platform using a bovine pericardium collagen membrane (BioR) loaded with human periodontal ligament stem cells (hPDLSCs) and endothelial differentiated cells from hPDLSCs (E-hPDLSCs) able to undergo toward osteoangiogenesis differentiation process. First, we have characterized at confocal laser scanning microscopy (CLSM) level the E-hPDLSCs phenotype profile, through CD31 and CD34 markers expression and the ability to tube vessel formation. Real Time-Polimerase Chain Reaction (RT-PCR) and western blotting analyses revealed the upregulation of Runt-related transcription factor 2 (RUNX2), Collagen 1A1 (COL1A1), Vascular Endothelial Growth Factor-A (VEGF-A) genes and proteins in the living construct composed by hPDLSCs + E-hPDSCs/BioR. Human PDLSCs + E-hPDLSCs/BioR construct showed also an enhacement of de novo synthesis of osteocalcin. Given that, the extracellular-signal-regulated kinase (ERK)/mitogen activated protein kinase (MAPK) transduction signaling was involved in the osteogenesis and angiogenesis process, the ERK1/2 protein level at biochemical level, in our experimental model, has been investigated. Our results evidenced an upregulation of ERK1/2 proteins level born in the living construct. In conclusion, we believe that the use of the hPDLSCs and E-hPDLSCs coculture togheter with BioR as substrate, could represent an efficient model able to activate through ERK1/2 signaling pathway the osteoangiogenesis process, and then representing a new potential engineered platform for surgeons during the repair and the healing of bone defects.

Human gingival mesenchymal stem cells pretreated with vesicular moringin nanostructures as a new therapeutic approach in a mouse model of spinal cord injury

Spinal cord injury (SCI) is a neurological disorder that arises from a primary acute mechanical lesion, followed by a pathophysiological cascade of events that leads to further spinal cord tissue damage. Several preclinical and clinical studies have highlighted the ability of stem cell therapy to improve long-term functional recovery in SCI. Previously, we demonstrated that moringin (MOR) treatment accelerates the differentiation process in mesenchymal stem cells inducing an early up-regulation of neural development associated genes. In the present study, we investigated the anti-inflammatory, anti-apoptotic, and regenerative effects of gingival mesenchymal stem cells (GMSCs) pretreated with nanostructured liposomes enriched with MOR in an animal model of SCI. SCI was produced by extradural compression of the spinal cord at levels T6-T7 in ICR (CD-1) mice. Animals were randomly assigned to the following groups: Sham, SCI, SCI + GMSCs (1 × 106  cell/i.v.), SCI + MOR-GMSCs (1 × 106  cell/i.v.). Our data show that MOR-treated GMSCs exert anti-inflammatory and anti-apoptotic activities. In particular, MOR-treated GMSCs are able to reduce the spinal cord levels of COX-2, GFAP, and inflammatory cytokines IL-1β and IL-6 and to restore spinal cord normal morphology. Also, MOR-treated GMSCs influenced the apoptotic pathway, by reducing Bax, caspase 3, and caspase 9 expressions.

Astragalus polysaccharides attenuated inflammation and balanced the gut microflora in mice challenged with Salmonella typhimurium

Salmonella typhimurium (S. t.) is one of the main pathogens that causes acute gastroenteritis. To evaluate the anti-inflammatory mechanism of Astragalus polysaccharide (APS) in vivo and its influence on the intestinal flora, BALB/c mice were infected with S. t. to establish a model of diarrhea. The disease activity index (DAI) scores showed that APS attenuated S. t.-induced weight loss and diarrhea in mice. APS significantly reduced the index of the liver and spleen as well as the ALT and AST levels in serum (P < 0.05). Hematoxylin and eosin (H&E) results indicated that APS significantly increased jejunum villus height and crypt depth and reduced the infiltration of inflammatory cells (P < 0.05). Additionally, APS increased the tight junction (TJ) proteins expression levels of ZO-1, Occludin and Claudin-1 in the jejunum. The results of 16S rDNA showed that APS significantly increased the number of Lactobacillus and Bifidobacterium spp. to normal levels (compared with the control group). In addition, APS significantly decreased the mRNA expression levels of the proinflammatory cytokines TNF-α, IL-1β, IL-6 and IL-17 in the jejunum (P < 0.01) as well as the proteins expression levels of COX-2 and iNOS (P < 0.05). Western blot confirmed that prefeeding with APS inhibited S. t.-induced expression of TLR4 and MyD88 in the jejunum and further inhibited nuclear factor-κB (NF-κB) activation, including the nuclear translocation of the p65 NF-κB subunit and the phosphorylation and degradation of IκB-α. This was the key to APS inhibition of the production of inflammatory factors and inflammatory mediators in the jejunum.

Curcumin/Liposome Nanotechnology as Delivery Platform for Anti-inflammatory Activities via NFkB/ERK/pERK Pathway in Human Dental Pulp Treated With 2-HydroxyEthyl MethAcrylate (HEMA)

Curcumin, primary component of the spice turmeric extracted from the rhizomes of Curcuma longa, represents the major anti-oxidant and anti-inflammatory substance found in turmeric, acting thought various mechanisms not completely understood. Curcumin modulates cytokines, growth factors, transcription factors, inflammatory molecules and cell signaling pathways. During restorative dentistry practice, free resin monomers of 2-hydroxyethyl methacrylate (HEMA) propagate through dentin micro-channel and pulp into the bloodstream affecting cellular integrity. The study highlights the significance of application of curcumin bioactive component into liposomal formulations (CurLIP) to restore the homeostasis of dental pulp stem cells (hDPSCs) in response to 3 and 5 mmol L^–1 HEMA treatment. Cell proliferation in combination with changes of the morphological features, proinflammatory cytokines secretion as Interleukin (IL) 6, IL8, Monocyte Chemoattractant Protein-1 (MCP1) and Interferon-gamma (IFNγ) were assayed along with the nuclear factor (NF)-kB, an inducible transcription factor involved in the activation of several cell processes associated to extracellular signal-regulated kinases (ERK) and posphorylated (p-) ERK pathway. Our results showed a decreased cell proliferation, morphological changes and upregulation of IL6, IL8, MCP1 and IFNγ in presence of 3 and 5 mmol L^–1 HEMA treatment. CurLIP therapy in hDPSCs provokes an increase in cell proliferation and the block of inflammatory cytokines secretion through the inhibitory regulation of NFkB/ERK and pERK signaling cascade. The natural nanocarrier CurLIP influences numerous biochemical and molecular cascades causing anti-inflammatory properties in response to HEMA treatment in human dental pulp stem cells, representing an innovative endodontic formulation able to improve the quality of dental care with a major human community impact.

Effect of short peptides on neuronal differentiation of stem cells

It has been demonstrated that short peptides play an important role in the transmission of biological information, modulation of transcription, and restoring genetically conditioned alterations occurring with age. Peptidergic regulation of homeostasis occupies an important place in physiological processes, which lead to the aging of cells, tissues, and organs, consisting in the involution of major regulatory systems-the nervous, the endocrine, and the immune. The effect of AED (Ala-Glu-Asp), KED (Lys-Glu-Asp), KE (Lys-Glu), AEDG (Ala-Glu-Asp-Gly) peptides and their compound on neuronal differentiation of human periodontal ligament stem cells (hPDLSCs) was studied by immunofluorescence and western blot analysis. Growth-Associated Protein 43 (GAP43), which implements neurotransmission mechanisms and neuroplasticity, demonstrated an increased expression in hPDLSCs cultured with a compound of all studied peptides and with KED alone. The peptide compound and KED, increase the expression of Nestin (neurofilament protein), expressed in early neuronal precursors in hPDLSCs cultures. Thus, the compound of peptides AEDG, KE, AED, and KED could promote the neuronal differentiation of hPDLSCs and be a promising tool for the study of peptides as a modulator of neurogenesis in neurodegenerative diseases studied in animal models.

Association of Toll-like receptor 4 polymorphisms with the risk of coronary artery disease in the ethnic Zhuang population of the Guangxi Province of China

OBJECTIVES

Toll-like receptor 4 (TLR4) is known to be involved in the innate immunity and inflammatory responses that plays a crucial role in the pathogenesis of coronary artery disease (CAD). This study aimed to examine the potential relationship of TLR4 polymorphisms and serum TLR4 protein levels and the risk of CAD in the ethnic Zhuang population of China.

METHODS

1171 serum samples were collected from Zhuang patients, including 556 CAD cases (≥50% luminal stenosis of any coronary vessel) and 615 normal healthy controls (subjects with no luminal stenosis in coronary arteries). Detection of TLR4 polymorphisms was by single base extension polymerase chain reaction (Snapshot PCR) and DNA sequencing (rs11536879A/G and rs11536889G/C) gene sequence in all subjects. Serum TLR4 protein concentrations was measured by ELISA.

RESULTS

There are significant differences in the allele and genotype frequencies of TLR4 gene rs11536889 between Chinese Zhuang CAD patients and controls, especially in the males. Male carriers of rs11536879 andrs11536889 variant alleles show an increased risk of CAD compared to non-carriers. Serum TLR4 protein levels of CAD patients are higher than controls and the levels tended to increase with the number of coronary artery lesions. Serum TLR4 protein levels of CAD patients showed no correlation with rs11536879 and rs11536889 polymorphisms.

CONCLUSIONS

The rs11536879 and rs11536889 polymorphisms of TLR4 gene and serum TLR4 protein levels may contribute to the occurrence and development of CAD. However, the rs11536879 and rs11536889 polymorphisms have no significant effects on the expression of serum TLR4 protein in Zhuang patients with CAD.

Engineered Extracellular Vesicles From Human Periodontal-Ligament Stem Cells Increase VEGF/VEGFR2 Expression During Bone Regeneration

Bone regeneration represents still a challenge, in particular for calvarium defects. Recently, the development of biomaterials with the addiction of stem cells is giving promising results for the treatment of bone defects. In particular, it was demonstrated that scaffolds enriched with mesenchymal stem cells (MSCs) and/or their derivatives, such as conditioned medium (CM) and extracellular vesicles (EVs), may improve bone regeneration. Moreover, given the deep link between osteogenesis and angiogenesis, a successful approach must also take into consideration the development of vascularization. In this work we evaluated the bone regeneration capacity of a collagen membrane (3D-COL) enriched with human periodontal-ligament stem cells (hPDLSCs) and CM or EVs or EVs engineered with polyethylenimine (PEI-EVs) in rats subjected to a calvarial defect. We evaluated also their capacity to induce angiogenic factors. At first, in vitro results showed an increased expression of osteogenic markers in hPDLSCs cultured with the 3D-COL and PEI-EVs, associated also with the increased protein levels of Vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR2). The increased expression of these proteins was confirmed also in vivo in rats implanted with the 3D-COL enriched with hPDLSCs and PEI-EVs. Moreover, histological examination evidenced in this group of rats the activation of bone regeneration and of the vascularization process. Also MicroCT imaging with morphometric analysis confirmed in rats transplanted with 3D-COL enriched with hPDLSCs and PEI-EVs an important regenerative process and a better integration level. All together, these results evidenced that the 3D-COL enriched with hPDLSCs and PEI-EVs may promote bone regeneration of calvaria defects, associated also with an increased vascularization.

LPS‑induced upregulation of the TLR4 signaling pathway inhibits osteogenic differentiation of human periodontal ligament stem cells under inflammatory conditions

Toll‑like receptor 4 (TLR4) is a transmembrane receptor responsible for the activation of a number of signal transduction pathways. Despite its involvement in inflammatory processes, the regulation of TLR4 signaling in human periodontal ligament stem cells (hPDLSCs) under inflammatory conditions remains to be fully elucidated. The present study aimed to clarify the regulatory mechanisms of the TLR4 signaling pathway and its role in the differentiation of hPDLSCs under inflammatory conditions. hPDLSCs from the periodontal tissues of healthy subjects and patients with periodontitis were identified by analyzing their cell surface marker molecules, and their osteogenic and adipogenic differentiation abilities. To determine the effect of TLR4 signaling on osteogenic and adipogenic differentiation under inflammatory conditions, cells were challenged with TLR4 agonist and antagonist under pluripotent differentiation conditions. Cell proliferation, apoptosis and migration were then determined using appropriate methods. The alkaline phosphatase (ALP) activity, Alizarin Red staining, Oil red O staining and relative gene and protein levels expression were also determined. The results showed that lipopolysaccharide (LPS)‑induced inflammation inhibited cell proliferation and migration, promoted cell apoptosis and affected the cell cycle. Under inflammatory conditions, the activation of TLR4 decreased the activity of ALP and the expression of osteogenic markers, including osteocalcin, Runt‑related transcription factor 2 and collagen I, compared with the control group, but increased the expression of adipogenesis‑related genes poly (ADP‑ribose) polymerase γ and lipoprotein lipase. The activation of TLR4 also induced the expression of proinflammatory cytokines interleukin‑1β, tumor necrosis factor‑α, nuclear factor‑κBP65 and TLR4, compared with that in the control group and the TLR4 antagonist group. The findings showed that LPS‑induced upregulation of the TLR4 signaling pathway inhibited osteogenic differentiation and induced adipogenesis of the hPDLSCs under inflammatory conditions. The present study provided a novel understanding of the physiopathology of periodontitis, and a novel avenue for targeted treatments based on stem cell regeneration.

Antioxidative Property and Molecular Mechanisms Underlying Geniposide-Mediated Therapeutic Effects in Diabetes Mellitus and Cardiovascular Disease

Geniposide, an iridoid glucoside, is a major component in the fruit of Gardenia jasminoides Ellis (Gardenia fruits). Geniposide has been experimentally proved to possess multiple pharmacological actions involving antioxidative stress, anti-inflammatory, antiapoptosis, antiangiogenesis, antiendoplasmic reticulum stress (ERS), etc. In vitro and in vivo studies have further identified the value of geniposide in a spectrum of preclinical models of diabetes mellitus (DM) and cardiovascular disorders. The antioxidative property of geniposide should be attributed to the result of either the inhibition of numerous pathological processes or the activation of various proteins associated with cell survival or a combination of both. In this review, we will summarize the available knowledge on the antioxidative property and protective effects of geniposide in DM and cardiovascular disease in the literature and discuss antioxidant mechanisms as well as its potential applications in clinic.