Mast cells and oral inflammation

Histochemical and immunohistochemical investigation of the number and localization of mast cells in the feline tongue

This is the first study to describe the subtypes, number and distribution of mast cells (MC) in cat tongue by histochemical and immunohistochemical methods. Six male adult felines' tongue tissue samples consist of the study's material. Samples were fixed in 10% formaldehyde. MC number and distribution in the feline tongue were assessed using toluidine blue. Also, sections taken from blocks were stained in alcian blue/safranin O (AB/SO) combined dyes to determine the MC subtypes. The Streptavidin biotin complex method using anti-chymase and anti-tryptase primary antibodies was used for immunohistochemistry. Metachromatic MCs were mainly observed in the lamina propria close to the multilayered keratinized stratified squamous epithelium. The high number of MCs in this region may be because the dorsal surface of the tongue plays an essential role in the defence system of tongue tissue and, thus, of the body as a whole. Additionally, the number of MCs stained with AB (+) (1.7 ± 0.08) in the feline tongue was statistically higher than those with SO (+) (0.18 ± 0.02). This might be interpreted as an indication that MC heterogeneity may be due not only to their staining properties but also to their localization. It is also conceivable that the high histamine content may be a factor in this. Tryptase-positive MCs were found in the loose connective tissue around blood vessels, between the glands, as solitary cells, or in groups of several cells. Chymase-positive MCs were observed more individually rather than in groups. Moreover, chymase-positive MCs were detected to be located in the filiform papillae subepithelial and in the blood vessels' immediate vicinity. Animals often lick themselves to clean themselves and promote healing. For this reason, it is very important to protect the tongue, which is in direct contact with the external environment, against foreign agents. Considering both the functional and protective properties of the tongue, we concluded that MCs may play a role in oral cavity immunity and protective effect.

Bioefficacy of Nga-Mon (Perilla frutescens) Fresh and Dry Leaf: Assessment of Antioxidant, Antimutagenicity, and Anti-Inflammatory Potential

Perilla leaves are known to be a rich source of polyphenols, which have been shown to exhibit various biological effects. This study aimed to compare the bioefficacies and bioactivities of fresh (PLE_f) and dry (PLE_d) Thai perilla (Nga-mon) leaf extracts. Phytochemical analysis indicated that both PLE_f and PLE_d were abundant in rosmarinic acid and bioactive phenolic compounds. PLE_d, which had higher levels of rosmarinic acid but lower levels of ferulic acid and luteolin than PLE_f, exhibited greater effectiveness in a free radical scavenging assay. Furthermore, both extracts were found to suppress intracellular ROS generation and exhibit antimutagenic activity against food-borne carcinogens in S. typhimurium. They also attenuated lipopolysaccharide-induced inflammation in RAW 264.7 cells by inhibiting the expression of nitric oxide, iNOS, COX-2, TNF-α, IL-1β, and IL-6 through the suppression of NF-κB activation and translocation. However, PLE_f exhibited a higher ability to suppress cellular ROS production and higher antimutagenic and anti-inflammatory activities than PLE_d, which can be attributed to its combination of phytochemical components. Overall, PLE_f and PLE_d have the potential to serve as natural bioactive antioxidant, antimutagenic, and anti-inflammatory agents to achieve potential health benefits.

Evaluation of peripheral nerve fibers and mast cells in burning mouth syndrome

Emerging evidence has revealed a cross-talk in the etiopathogenesis of burning mouth syndrome (BMS) related to peripheral nerve fibers (NF) and neuropeptides secreted by mast cells. Here, we investigated the S-100+ density and PGP 9.5+ integrity of peripheral NF and the tryptase+ mast cell density in the oral mucosa of BMS patients and healthy individuals. A total of 23 oral mucosa specimens (12 BMS and 11 controls) were evaluated. The clinical diagnosis of BMS was based on a careful examination, excluding other local and systemic causes. Samples were taken from an incisional biopsy of the tongue mucosa of individuals with symptomatic BMS, while the margins of the non-neoplastic tongue biopsy served as controls of healthy individuals. Immunohistochemistry was performed to determine the density/mm2 of S-100+, PGP 9.5+ peripheral NF, and tryptase+ mast cells. Similar densities of S-100+, PGP 9.5+ peripheral NF, and tryptase+ mast cells were found in cases of BMS, with a median value of 3.70, 0.70, and 29.24/mm2, respectively, and in the control group, with a median value of 2.60, 0.80, and 26.01/mm2, respectively (p > 0.05). Moreover, the relationship between S100+ and PGP 9.5+ peripheral NF was the same in both groups (p = 0.70). This study demonstrated that there were no alterations in the density and integrity of peripheral NF in the tongue of symptomatic BMS patients. However, the sensitization of peripheral NF in this disease may not depend on mast cell density.

Molecular Pathogenesis of Human Immunodeficiency Virus-Associated Disease of Oropharyngeal Mucosal Epithelium

The oropharyngeal mucosal epithelia have a polarized organization, which is critical for maintaining a highly efficient barrier as well as innate immune functions. In human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) disease, the barrier and innate immune functions of the oral mucosa are impaired via a number of mechanisms. The goal of this review was to discuss the molecular mechanisms of HIV/AIDS-associated changes in the oropharyngeal mucosa and their role in promoting HIV transmission and disease pathogenesis, notably the development of opportunistic infections, including human cytomegalovirus, herpes simplex virus, and Epstein-Barr virus. In addition, the significance of adult and newborn/infant oral mucosa in HIV resistance and transmission was analyzed. HIV/AIDS-associated changes in the oropharyngeal mucosal epithelium and their role in promoting human papillomavirus-positive and negative neoplastic malignancy are also discussed.

Identification of the characteristics of infiltrating immune cells in pulpitis and its potential molecular regulation mechanism by bioinformatics method

OBJECTIVE

The inflammation of dental pulp will also trigger an immune response. The purpose of this study is to demonstrate the immune cell's function and explore their regulatory molecules and signal pathways in pulpitis.

METHOD

The CIBERSORTx method was used to quantitatively analyze 22 types of immune cells infiltrating in the GSE77459 dataset of dental pulp tissues. The immune-related differential genes (IR-DEGs) were further screened and enriched for the GO and KEGG pathways. Protein-protein interaction (PPI) networks were constructed and the hub IR-DEGs were screened. Finally, we constructed the regulatory network of hub genes.

RESULTS

The GSE77459 dataset screened 166 IR-DEGs and was enriched for three signal pathways involved in pulpitis development: chemokine signaling, TNF signaling, and NF-κB signaling. Significant differences in immune cell infiltration were observed between normal and inflamed dental pulp. The proportions of M0 macrophages, neutrophils, and follicular helper T cells were significantly higher than that of the normal dental pulp, while the proportions of resting mast cells, resting dendritic cells, CD8 T cells, and monocytes were significantly lower. The random forest algorithm concluded that M0 macrophages and neutrophils were the two most important immune cells. We identified five immune-related hub genes IL-6, TNF-α, IL-1β, CXCL8, and CCL2. In addition, IL-6, IL-1β, and CXCL8 are highly correlated with M0 macrophages and neutrophils, and the five hub genes have many shared regulatory molecules: four miRNAs and two lncRNAs, three transcription factors.

CONCLUSION

Immune cell infiltration plays an important role in pulpitis among which M0 macrophages and neutrophils are the most significant immune cells. IL-6, TNF-α, IL-1, CXCL8, and CCL2 may be essential molecule of the immune response regulation network in pulpitis. This will help us understand the immune regulatory network in pulpitis.

Substance P aggravates ligature-induced periodontitis in mice

Periodontitis is one of the most common oral diseases in humans, affecting over 40% of adult Americans. Pain-sensing nerves, or nociceptors, sense local environmental changes and often contain neuropeptides. Recent studies have suggested that nociceptors magnify host response and regulate bone loss in the periodontium. A subset of nociceptors projected to periodontium contains neuropeptides, such as calcitonin gene-related peptide (CGRP) or substance P (SP). However, the specific roles of neuropeptides from nociceptive neural terminals in periodontitis remain to be determined. In this study, we investigated the roles of neuropeptides on host responses and bone loss in ligature-induced periodontitis. Deletion of tachykinin precursor 1 (Tac1), a gene that encodes SP, or treatment of gingiva with SP antagonist significantly reduced bone loss in ligature-induced periodontitis, whereas deletion of calcitonin related polypeptide alpha (Calca), a gene that encodes CGRP, showed a marginal role on bone loss. Ligature-induced recruitment of leukocytes, including neutrophils, and increase in cytokines leading to bone loss in periodontium was significantly less in Tac1 knockout mice. Furthermore, intra-gingival injection of SP, but not neurokinin A, induced a vigorous inflammatory response and osteoclast activation in alveolar bone and facilitated bone loss in ligature-induced periodontitis. Altogether, our data suggest that SP plays significant roles in regulating host responses and bone resorption in ligature-induced periodontitis.

The Interactions of Magnesium Sulfate and Cromoglycate in a Rat Model of Orofacial Pain; The Role of Magnesium on Mast Cell Degranulation in Neuroinflammation

Mast cell degranulation impacts the development of pain and inflammation during tissue injury. We investigated the antinociceptive effect of a combination of cromoglycate and magnesium in the orofacial model of pain and the histological profile of the effect of magnesium in orofacial pain. In male Wistar rats, formalin (1.5%, 100 µL) was injected subcutaneously into the right upper lip of rats after cromoglycate and/or magnesium. Pain was measured as the total time spent on pain-related behavior. Toluidine blue staining was used to visualize mast cells under the light microscope. In the formalin test, in phase 1, magnesium antagonized the antinociceptive effect of cromoglycate, while in phase 2, it potentiated or inhibited its effect. Magnesium significantly reduced mast cell degranulation in the acute phase by about 23% and in the second phase by about 40%. Pearson’s coefficient did not show a significant correlation between mast cell degranulation and pain under treatment with magnesium. The cromoglycate–magnesium sulfate combination may prevent the development of inflammatory orofacial pain. The effect of a combination of cromoglycate–magnesium sulfate depends on the nature of the pain and the individual effects of the drugs. Magnesium reduced orofacial inflammation in the periphery, and this effect did not significantly contribute to its analgesic effect.

Updates on immunological mechanistic insights and targeting of the oral lichen planus microenvironment

Oral lichen planus (OLP) is a chronic immune inflammatory disease that is an oral potentially malignant disorder (OPMD), occurs in the oral mucosa and affects approximately 0.5% to 4% of the general population. There are usually five types of OLP: reticular/papular, plaque-like, atrophic/erythematous, erosive/ulcerative, and bullous. Furthermore, the chance of causing oral squamous cell carcinoma (OSCC) is 1.4%. Although the etiology of OLP is still unknown, accumulating evidence supports that immune dysregulation may play a vital role in the pathogenesis of OLP, especially the massive production of various inflammatory cells and inflammatory mediators. In this review, we focus on the relationship between OLP and its immune microenvironment. We summarize current developments in the immunology of OLP, summarizing functional cell types and crucial cytokines in the OLP immune microenvironment and the underlying mechanisms of key signaling pathways in the OLP immune microenvironment. We highlight the application potential of targeted immune microenvironment therapy for OLP.

Ferulic Acid: A Natural Phenol That Inhibits Neoplastic Events through Modulation of Oncogenic Signaling

Despite the immense therapeutic advances in the field of health sciences, cancer is still to be found among the global leading causes of morbidity and mortality. Ethnomedicinally, natural bioactive compounds isolated from various plant sources have been used for the treatment of several cancer types and have gained notable attention. Ferulic acid, a natural compound derived from various seeds, nuts, leaves, and fruits, exhibits a variety of pharmacological effects in cancer, including its proapoptotic, cell-cycle-arresting, anti-metastatic, and anti-inflammatory activities. This review study presents a thorough overview of the molecular targets and cellular signaling pathways modulated by ferulic acid in diverse malignancies, showing high potential for this phenolic acid to be developed as a candidate agent for novel anticancer therapeutics. In addition, current investigations to develop promising synergistic formulations are also discussed.

Chemoprevention of 4NQO-Induced Mouse Tongue Carcinogenesis by AKT Inhibitor through the MMP-9/RhoC Signaling Pathway and Autophagy

Oral cancer (OC), the most common cancer in the head and neck, which has a poor prognosis, histopathologically follows a stepwise pattern of hyperplasia, dysplasia, and cancer. Blocking the progression of OC in the precancer stage could greatly improve the survival and cure rates. AKT protein plays a critical role in the signal transduction of cancer cells, and we found that AKT was overexpressed in human OC samples through analysis of TCGA database. Therefore, this study is aimed at investigating the chemopreventive effect of an AKT inhibitor (MK2206 2HCl) on OC. In vivo, we established a 4-nitroquinoline-1-oxide- (4NQO-) induced mouse tongue carcinogenesis model to investigate the potential chemopreventive effect of MK2206 2HCl on mouse OC resulting from 4NQO. The results showed that MK2206 2HCl could significantly reduce the incidence rate and growth of OC, inhibit the transformation of dysplasia to cancer in the 4NQO-induced mouse tongue carcinogenesis model, and simultaneously markedly suppress cell proliferation, angiogenesis, and mast cell (MC) infiltration in 4NQO-induced mouse tongue cancers. In vitro, our results revealed that MK2206 2HCl could also inhibit oral squamous cell carcinoma (OSCC) cell malignant biological behaviors, including cell proliferation, colony formation, cell invasion, and migration, while promoting apoptosis. Mechanistic studies revealed that MK2206 2HCl suppressed matrix metalloproteinase 9 (MMP-9) and RhoC expression and promoted autophagy gene LC3 II expression. In summary, our findings demonstrated the chemopreventive effect of MK2206 2HCl on the 4NQO-induced mouse tongue carcinogenesis model, which likely has an underlying mechanism mediated by the MMP-9/RhoC signaling pathway and autophagy.

Research Progress on Therapeutic Effect and Mechanism of Propolis on Wound Healing

Propolis is a kind of reduct collected by bees from various plant sources. Because propolis is a mixture, it has a variety of biological activities, excellent anti-inflammatory and bactericidal effects. Especially in the treatment of infectious wounds, acute wounds, burns, and scalds and promoting wound healing, more and more scientists began to apply it to the research field of wound healing. The standard preparation of propolis combined with other compound components has a safer and less toxic effect in the treatment of trauma. In order to more effectively use propolis products in wound treatment. This paper reviews the effect and treatment mechanism of propolis on different types of wound healing, as well as the synergistic effect of propolis and other compounds, in order to provide ideas for the further exploration of the biological activity and pharmacological function of propolis in the future, as well as its in-depth development in the field of wound healing. It will also provide a theoretical reference for the further development and utilization of propolis.

Dental management of a patient with systemic mastocytosis

Mastocytosis is a term encompassing a group of clinical disorders characterised by clonal proliferation of abnormal mast cells (MCs) in organ systems of the body. Mastocytosis can be systemic (with or without skin involvement) or cutaneous, and can affect organs including bone marrow, liver, spleen, lymph nodes and mucosal surfaces. Patients with systemic mastocytosis (SM) are susceptible to triggers that could cause activation of abnormal MCs, resulting in multiorgan dysfunction and life-threatening anaphylactic reactions. Mastocytosis has a number of ramifications for the dental management of a patient with the condition. Patients are at increased risk of complications due to a number of risk factors for MC activation present within the dental context, including stress, certain prescribed drugs, oral hygiene products and dental materials. This report presents the oral management of an adult with SM, discussing the implications of the condition within the context of the limited existing literature on the subject.

Principal component analysis of salivary cytokines and hormones in the acute stress response

The acute stress response is characterized by activation of multiple interconnected systems in the body, resulting in the release of a flood of hormones and immune mediators into circulation. In addition to detection of these molecules in the serum, saliva can serve as a source of these markers as well and can be collected in a non-invasive way. The complete profile of salivary biomarkers associated with the hypothalamic pituitary adrenal/gonadal axes and the immune system during the acute stress response has not been fully elucidated. In a cohort of 62 first responders engaged in a stress training exercise, we set out to determine patterns of cytokine, chemokine and hormone shifts during the acute stress response. Salivary samples were collected immediately before (pre-stress), immediately after (post-stress) and 1 h after the stress test (recovery). Multiplex ELISA panels of 42 cytokines and 6 steroid and thyroid hormones were used to determine concentrations of these biomarkers during the three aforementioned time points. Principal components analysis was conducted to determine patterns in the large data sets collected. In our ≥0.3 loading principal components analysis, for pre-stress vs. post, post-stress vs. recovery and pre-stress vs. recovery, a total of three, four and three factors accounted for 56.6, 68.34, and 61.70% of the biomarker variation for each phase respectively. In the ≥0.7 loading principal components analysis, three, four and three factors were found for pre-stress vs. post, post-stress vs. recovery and pre-stress vs. recovery stages, respectively. Of note, in our ≥0.3 loading principal components analysis, MCP1 was present in all three factors from pre-stress to post-stress, and fractalkine was found to be in all four factors post-stress vs. recovery and pre vs. recovery from stress. Additionally, hormones testosterone, estradiol, T4 and T3 grouped together consistently in the same factor for all phases of acute stress in both ≥0.3 and ≥0.7 principal components analysis. Overall, our results identified specific patterns of immune markers and hormones that shift during acute stress and warrant further investigation to understand their mechanistic role in regulating the stress response.

Preliminary Protocol Development of a HPLC-TBARS-EVSC (Ex Vivo Stratum Corneum) Assay for Skin Research: Application in a Sunscreen System

Considering the importance of the cutaneous tissue investigation and the need for the development of new protocols to non-invasively establish the safety and efficacy of dermocosmetics and topical products, we aimed at developing an HPLC-TBARS-EVSC (high performance liquid chromatography–thiobarbituric acid reactive species–ex vivo stratum corneum) assay for the lipid peroxidation measurement on subjects’ stratum corneum (SC) obtained by tape stripping; additionally, we applied the HPLC-TBARS-EVSC assay in an emulsified sunscreen system containing ethylhexyl triazone and bemotrizinol as UV filters. HPLC analysis was performed in isocratic mode with 35% methanol/65% phosphate buffer (pH 7.0) as the mobile phase. The diode detector was set at 532 nm to quantify the malondialdehyde (MDA)-TBA adduct. An ex vivo tape stripping method was applied in 10 volunteers in three pre-defined regions of the volar forearms: the control; the irradiated; and the site containing the sunscreen (2.0 mg·cm−2). Ten adhesive tapes per region were used for SC removal. An exclusive ex vivo protocol to measure SC lipid peroxidation was preliminarily developed with linearity and selectivity. The protocol suggested the use of an artificial irradiation dose (5506 KJ·m−2) to improve the assay response from the SC. The sunscreen system had a significative decrease in SC lipoperoxidative damage compared to the control. Our protocol can aid in the efficacy establishment of anti-UV and antioxidant agents, for instance, in studies that aim at elucidating the level of SC lipid peroxidation and even in carrying out baseline investigations characterizing different ethnicities and genders.

Morphological and Histopathological Study of Autopsied Patients with Atherosclerosis and HIV

BACKGROUND

Chronic infection by HIV evolves with a vascular inflammatory action causing endothelial dysfunction. The action of the virus, as well as the side effects of antiretroviral drugs, contribute to the progression of cardiovascular diseases. The present study aimed to evaluate the percentage of collagen fibers and the density of mast cells, chymase and tryptase, in aortas of patients with and without HIV, and also patients with and without atherosclerosis.

METHODS

Aortic fragments were obtained from autopsied patients aged 22-69 years and selected regardless of the cause of death or underlying disease. The samples were divided into four groups, (1) Group with HIV and with atherosclerosis; (2) Group with HIV and without atherosclerosis; (3) Group without HIV and with atherosclerosis; (4) Group without HIV and without atherosclerosis (Control). The percentage of collagen fibers was analyzed in the intima-media layer and the density of mast cells was analyzed in all aortic layers. Graphpad Prism 5.0^® software was used for statistical analysis.

RESULTS

There were more collagen fibers in HIV patients, with or without atherosclerosis. The group with HIV and atherosclerosis presented a higher density of chymase and tryptase mast cells. The correlation between collagen fibers and age was negative in the non-HIV group and with atherosclerosis.

CONCLUSION

The inflammatory process resulting from HIV infection may be relevant in the alteration of aortic collagen fibers and in triggering or accelerating atherosclerosis. The study is important because HIV patients have increased risks for the development of cardiovascular diseases, and follow-up is necessary to prevent such diseases.

Tumor associated mast cells: biological roles and therapeutic applications

Mast cells (MCs) are immune cells of the myeloid lineage and are present in connective tissues throughout the body. The activation and degranulation of MCs significantly modulates many aspects of physiological and pathological conditions in various settings. Recent data have expanded the concept that inflammation is a critical component for tumor progression. Interestingly, three of the most aggressive human cancers, malignant melanoma, breast carcinoma and colorectal adenocarcinoma, are commonly associated with a marked host response comprising of various inflammatory cells, but especially MCs around the tumor periphery. A systematic review of the literature was performed based on the English titles listed in the PubMed, EBSCO, Cochrane, Science Direct, ISI web Science, and SciELO databases using the keywords. Abstracts and full-text articles were assessed. This review summarizes the current understanding of the role of MCs in tumor progression.

Top-Down Proteomics of Human Saliva Discloses Significant Variations of the Protein Profile in Patients with Mastocytosis

Mastocytosis is a myeloproliferative neoplasm causing abnormal clonal mast cell accumulation in different tissues, such as skin and bone marrow. A cutaneous subtype (CM) is distinguished from a systemic one (SM); SM patients can be grouped into SM with (SM+C) or without (SM-C) additional cutaneous lesions, and their classification is often challenging. This study was purposed to highlight variations in the salivary proteome of patients with different mastocytosis subtypes and compared to healthy controls. A top-down proteomics approach coupled to a label-free quantitation revealed salivary profiles in patients different from those of controls and a down-regulation of peptides/proteins involved in the mouth homeostasis and defense, such as statherin, histatins, and acidic proline-rich proteins (aPRPs), and in innate immunity and inflammation, such as the cathepsin inhibitors, suggesting a systemic condition associated with an exacerbated inflammatory state. The up-regulation of antileukoproteinase and S100A8 suggested a protective role against the disease status. The two SM forms were distinguished by the lower levels of truncated forms of aPRPs, statherin, P-B peptide, and cystatin D and the higher levels of thymosin β4 and α-defensins 1 and 4 in SM-C patients with respect to SM+C. Data are available via ProteomeXchange with identifier PXD017759.

Top-Down Proteomics of Human Saliva Discloses Significant Variations of the Protein Profile in Patients with Mastocytosis

Mastocytosis is a myeloproliferative neoplasm causing abnormal clonal mast cell accumulation in different tissues, such as skin and bone marrow. A cutaneous subtype (CM) is distinguished from a systemic one (SM); SM patients can be grouped into SM with (SM+C) or without (SM-C) additional cutaneous lesions, and their classification is often challenging. This study was purposed to highlight variations in the salivary proteome of patients with different mastocytosis subtypes and compared to healthy controls. A top-down proteomics approach coupled to a label-free quantitation revealed salivary profiles in patients different from those of controls and a down-regulation of peptides/proteins involved in the mouth homeostasis and defense, such as statherin, histatins, and acidic proline-rich proteins (aPRPs), and in innate immunity and inflammation, such as the cathepsin inhibitors, suggesting a systemic condition associated with an exacerbated inflammatory state. The up-regulation of antileukoproteinase and S100A8 suggested a protective role against the disease status. The two SM forms were distinguished by the lower levels of truncated forms of aPRPs, statherin, P-B peptide, and cystatin D and the higher levels of thymosin β4 and α-defensins 1 and 4 in SM-C patients with respect to SM+C. Data are available via ProteomeXchange with identifier PXD017759.

Streptococcal H2O2 inhibits IgE-triggered degranulation of RBL-2H3 mast cell/basophil cell line by inducing cell death

Mast cells and basophils are central players in allergic reactions triggered by immunoglobulin E (IgE). They have intracellular granules containing allergic mediators (e.g., histamine, serotonin, inflammatory cytokines, proteases and β-hexosaminidase), and stimulation by IgE-allergen complex leads to the release of such allergic mediators from the granules, that is, degranulation. Mast cells are residents of mucosal surfaces, including those of nasal and oral cavities, and play an important role in the innate defense system. Members of the mitis group streptococci such as Streptococcus oralis, are primary colonizers of the human oral cavity. They produce hydrogen peroxide (H₂O₂) as a by-product of sugar metabolism. In this study, we investigated the effects of streptococcal infection on RBL-2H3 mast cell/basophil cell line. Infection by oral streptococci did not induce degranulation of the cells. Stimulation of the RBL-2H3 cells with anti-dinitrophenol (DNP) IgE and DNP-conjugated human serum albumin triggers degranulation with the release of β-hexosaminidase. We found that S. oralis and other mitis group streptococci inhibited the IgE-triggered degranulation of RBL-2H3 cells. Since mitis group streptococci produce H₂O₂, we examined the effect of S. oralis mutant strain deficient in producing H₂O_2, and found that they lost the ability to suppress the degranulation. Moreover, H₂O₂ alone inhibited the IgE-induced degranulation. Subsequent analysis suggested that the inhibition of degranulation was related to the cytotoxicity of streptococcal H₂O₂. Activated RBL-2H3 cells produce interleukin-4 (IL-4); however, IL-4 production was not induced by streptococcal H₂O₂. Furthermore, an in vivo study using the murine pollen-induced allergic rhinitis model suggested that the streptococcal H₂O₂ reduces nasal allergic reaction. These findings reveal that H₂O₂ produced by oral mitis group streptococci inhibits IgE-stimulated degranulation by inducing cell death. Consequently, streptococcal H₂O₂ can be considered to modulate the allergic reaction in mucosal surfaces.

Mast cell expression in oral lichen planus: A systematic review

Lichen planus is a common chronic, inflammatory, immune-mediated mucocutaneous disorder affecting the skin and mucosa. The role of mast cells in the genesis of lichen planus has been debated. Establishing a definitive part played by mast cells and its degranulation would possibly provide a permanent, cost-effective treatment modality for oral lichen planus (OLP). This review aims to study the expression of mast cells qualitatively and quantitatively in OLP. The research questions were framed to assess the mast cell count, localization within the epithelium basement membrane zone and degranulation of mast cells. We performed a systematic search of PubMed, Medline, Cochrane and Web of Science. We found a total of 120 studies from which 12 were found suitable for the review. There is a marked increase in the number of mast cells in OLP. The mast cells were seen in increased numbers in the epithelial and connective tissue junction at areas of basement membrane disruption. There was also an increase in the degranulation of mast cells. It is evident that there is an increase in the mast cell number in lichen planus and its subsequent degranulation.

Anti-hypertensive Effect of Cereal Antioxidant Ferulic Acid and Its Mechanism of Action

Ferulic acid is a simple phenolic acid found mainly in cereals and grains, used as an antioxidant and food preservative. Recent evidence suggests that ferulic acid possess anti-inflammatory, anti-diabetic, anticancer, and cardioprotective properties. Several investigations also have shown that ferulic acid rich food might prevent hypertension. As a potent scavenger of free radicals (ROS, reactive oxygen species), ferulic acid attenuates oxidative stress, which is responsible for lowering elevated blood-pressure through improved endothelial function and increased bioavailability of the nitric oxide in the arterial vasculature. This review article describes the role of ferulic acid in the pathophysiology of vascular dysfunction and hypertension along with highlighted the merit of further scientific and clinical exploration.

Explanation for the signs and symptoms of tooth eruption: mast cells

This study contributes to the understanding of the mechanisms associated with signs and symptoms of tooth eruption, by investigating the presence of mast cells in pericoronal tissues during the intraosseous (Group 1) and submucosal (Group 2) phases of eruption. We compared findings for these two groups with each other and with those for the oral mucosa (Group 3). In each group, 14 specimens were analyzed microscopically after hematoxylin and eosin staining and immunohistochemical analysis of c-Kit and tryptase expression. Results revealed that the number and density of mast cells is different in follicular tissues according to the eruption phase, which may mean that: 1) masticatory trauma of the oral mucosa and dental follicles in the submucosa may explain why reduced enamel epithelium exposes enamel to the cells of the connective tissue; 2) exposure of antigenic enamel proteins might correspond to the release of sequestered antigens, which may lead to the interaction of IgE and a greater number of mast cells in the region; and 3) the consequent degranulation and the local release of mediators, such as histamine, leukotrienes, prostaglandins, proteases, cytokines and growth factors, contribute to the understanding of signs and symptoms associated with tooth eruption.

Immunohistochemical quantification of mast cells in inflamed and noninflamed pulp tissue

Background

Dental pulp inflammation is a very complex process due to its situation in low compliance (confined environment) surrounded by mineralized dentin. Mast cells are one of the mediators of inflammation. Immunohistochemical localization of mast cells by anti-tryptase antibodies in formalin-fixed paraffin-embedded sections has been shown to be highly specific. The aim of the present study is to quantify the mast cells in inflamed and noninflamed human pulp tissue using immunohistochemical analysis.

Materials and Methods

Immunohistochemical localization of mast cells by anti-tryptase antibody was done in 15 inflamed and 15 noninflamed formalin-fixed paraffin-embedded pulp tissue. A number of mast cell per five high-power fields were performed using three observers and the mean was calculated. Statistical analysis was performed using t-test.

Results

The results of the present study showed an increased number of mast cells in inflamed pulp in comparison with noninflamed pulp.

Conclusion

Thus, the presence of mast cells in pulp inflammation could be used as a diagnostic marker. It can also aid in the management of pulpitis as mast cell stabilizers and antihistaminic agents could be used to control pulpal pain and inflammation.

Role of mast cells in inflammatory and reactive pathologies of pulp, periapical area and periodontium

Mast cells (MCs) have been discovered over 130 years ago; their function was almost exclusively linked to allergic affections. At the time being, it is well known that MCs possess a great variety of roles, in both physiologic and pathologic conditions. In the oral tissues, MCs release different pro-inflammatory cytokines and tumor necrosis factor-alpha that promote leukocyte infiltration in various inflammatory states of the oral cavity. These cells play a key role in the inflammatory process and, as a consequence, their number changes in different pathologic conditions of the oral cavity, such as gingivitis and periodontitis. By understanding the role of MCs in the pathogenesis of different inflammatory diseases of the oral cavity, these cells may become therapeutic targets that could possibly improve the prognosis. Therefore, this review summarizes the current understanding of the role of MCs in various inflammatory pulpal, periapical and periodontal pathophysiological conditions.

Antimicrobial agent triclosan disrupts mitochondrial structure, revealed by super-resolution microscopy, and inhibits mast cell signaling via calcium modulation

The antimicrobial agent triclosan (TCS) is used in products such as toothpaste and surgical soaps and is readily absorbed into oral mucosa and human skin. These and many other tissues contain mast cells, which are involved in numerous physiologies and diseases. Mast cells release chemical mediators through a process termed degranulation, which is inhibited by TCS. Investigation into the underlying mechanisms led to the finding that TCS is a mitochondrial uncoupler at non-cytotoxic, low-micromolar doses in several cell types and live zebrafish. Our aim was to determine the mechanisms underlying TCS disruption of mitochondrial function and of mast cell signaling. We combined super-resolution (fluorescence photoactivation localization) microscopy and multiple fluorescence-based assays to detail triclosan's effects in living mast cells, fibroblasts, and primary human keratinocytes. TCS disrupts mitochondrial nanostructure, causing mitochondria to undergo fission and to form a toroidal, "donut" shape. TCS increases reactive oxygen species production, decreases mitochondrial membrane potential, and disrupts ER and mitochondrial Ca²⁺ levels, processes that cause mitochondrial fission. TCS is 60 × more potent than the banned uncoupler 2,4-dinitrophenol. TCS inhibits mast cell degranulation by decreasing mitochondrial membrane potential, disrupting microtubule polymerization, and inhibiting mitochondrial translocation, which reduces Ca²⁺ influx into the cell. Our findings provide mechanisms for both triclosan's inhibition of mast cell signaling and its universal disruption of mitochondria. These mechanisms provide partial explanations for triclosan's adverse effects on human reproduction, immunology, and development. This study is the first to utilize super-resolution microscopy in the field of toxicology.

Association Between Mast Cells and Collagen Maturation in Chronic Periodontitis in Humans

Mast cells (MCs) can influence the maturation of collagen fibers. This study evaluated the relationship between the distribution and degranulation of MCs and collagen maturation in human gingival tissue in chronic periodontitis. A total of 16 specimens of patients clinically diagnosed as periodontitis and 18 controls clinically diagnosed as healthy or gingivitis were included. Immunohistochemistry and Picrosirius staining were performed to identify MCs and assess collagen fibers, respectively. Chi-square, t test, and Pearson's correlation test ( p<0.05) were used. In control specimens, there was a positive association between MCs in the connective tissue and the presence of immature collagen ( p=0.001); in periodontitis samples, this association was not confirmed ( p≥0.12). There was no significant relationship between periodontal diagnosis and collagen maturation or MC degranulation ( p≥0.35). MC density was significantly higher ( p=0.04) in periodontitis tissue (339.01 ± 188.94 MCs/mm²) than in control tissue (211.14 ± 131.13 MCs/mm²) in the area of connective tissue containing inflammatory infiltrate. There was a correlation between the number of MCs and probing depth ( r = 0.34, p=0.04). MCs are involved in the pathogenesis of periodontal diseases and might be associated with collagen maturation in periodontal tissue during the early stages of periodontal disease pathogenesis.

Role of Mast Cells in Oral Lichen Planus and Oral Lichenoid Reactions

Introduction

Oral lichen planus (OLP) is a chronic T cell mediated disease of oral mucosa, skin, and its appendages with a prevalence of 0.5 to 2.6% worldwide. Oral lichenoid reactions (OLR) are a group of lesions with diverse aetiologies but have clinical and histological features similar to OLP, thereby posing a great challenge in differentiating both lesions. Mast cells are multifunctional immune cells that play a major role in the pathogenesis of lichen planus by release of certain chemical mediators. Increased mast cell densities with significant percentage of degranulation have been observed as a consistent finding in pathogenesis of oral lichen planus.

Aim

The current study was aimed at quantifying the mast cells in histopathological sections of OLP and OLR thereby aiding a means of distinguishing these lesions.

Materials and Methods

The study group involved 21 cases of oral lichen planus, 21 cases of oral lichenoid reactions, and 10 control specimens of normal buccal mucosa. All the cases were stained with Toluidine Blue and routine haematoxylin and eosin and the mast cells were quantified.

Statistical Analysis Used

The results were analyzed using the Kruskal–Wallis test and an intergroup analysis was performed using Mann–Whitney U test.

Conclusion

The number of mast cells showed an increased value in oral lichen planus when compared to oral lichenoid reaction and thus an estimation of mast cells count could aid in distinguishing OLP from OLR histopathologically.

Therapeutic Effects of Breviscapine in Cardiovascular Diseases: A Review

Breviscapine is a crude extract of several flavonoids of Erigeron breviscapus (Vant.) Hand.-Mazz., containing more than 85% of scutellarin, which has been traditionally used in China as an activating blood circulation medicine to improve cerebral blood supply. Accumulating evidence from various in vivo and in vitro studies has shown that breviscapine exerts a broad range of cardiovascular pharmacological effects, including vasodilation, protection against ischaemia/reperfusion (I/R), anti-inflammation, anticoagulation, antithrombosis, endothelial protection, myocardial protection, reduction of smooth muscle cell migration and proliferation, anticardiac remodeling, antiarrhythmia, blood lipid reduction, and improvement of erectile dysfunction. In addition, several clinical studies have reported that breviscapine could be used in conjunction with Western medicine for cardiovascular diseases (CVDs) including coronary heart disease, myocardial infarction, hypertension, atrial fibrillation, hyperlipidaemia, viral myocarditis, chronic heart failure, and pulmonary heart disease. However, the protective effects of breviscapine on CVDs based on experimental studies along with its underlying mechanisms have not been reviewed systematically. This paper reviewed the underlying pharmacological mechanisms in the cardioprotective effects of breviscapine and elucidated its clinical applications.

Ferulic Acid and Naturally Occurring Compounds Bearing a Feruloyl Moiety: A Review on Their Structures, Occurrence, and Potential Health Benefits

The ubiquitous compound 4-hydroxy-3-methoxycinnamic acid, also known as ferulic acid (FA), constitutes a bioactive ingredient of many foods that may offer beneficial effects against disorders related to oxidative stress, including cancer, diabetes, and neurodegenerative diseases. This review discusses the antioxidant properties of FA, establishing relationships to several biological activities already described for this natural product. Next, 387 naturally occurring compounds, all isolated from plants and published between 1990 and 2015, the structures of which bear 1 or more feruloyl moieties, are covered in this review along with their structural formulas, botanical sources, and bioactivities. The compounds' distribution, structural patterns, bioactivities, and perspectives on food research are also succinctly discussed.

The role of mast cells in oral squamous cell carcinoma

The mast cells are initial effective lineage in both humoral and adaptive immunity. They are ubiquitous in skin, mucosa, and in function. They contain biologically essential and dynamic mediators in healthy and harmful conditions of tissue. Mast cell malfunctioning could be attributed to various chronic allergic diseases. Considerately, emerging evidence of mast cell involvement in various cancers shows them to have both positive and negative roles in tumour growth. It mostly indulges in tumour progression and metastasis via angiogenesis, extracellular matrix degradation, and mitogenic activity in the tumour microenvironment. The current paper reviewed research papers on mast cells in oral squamous cell carcinoma through the PubMed database from 1980 to the present date. The present paper is an attempt to summarise the research reports on the role of mast cells in oral squamous cell carcinoma. Further to this note, this paper also outlines the role of mast cells in normal physiological processes and tumour biology.

Mast Cells: Key Players in the Shadow in Oral Inflammation and in Squamous Cell Carcinoma of the Oral Cavity

Although mast cells (MCs) have been discovered over 130 years ago, their function was almost exclusively linked to allergic affections. At the time being, it is well known that MCs possess a great variety of roles, in both physiologic and pathologic conditions. In the oral tissues, MCs release different proinflammatory cytokines, tumor necrosis factor alpha (TNF-α), that promote leukocyte infiltration in various inflammatory states of the oral cavity. These cells play a key role in the inflammatory process and, as a consequence, their number changes in different pathologic conditions of the oral cavity, like gingivitis, periodontitis, and so on. MCs also represent a rich source of proteases, especially of mast cell tryptase and chymase, which directly degrade the extracellular matrix through their proteolytic activity and thus indirectly stimulate angiogenesis and facilitate invasion and metastasis. It may be stated that mast cells could have an impact on primary tumor development, progression, and metastases in oral squamous cell carcinoma. By understanding the role of mast cells in the pathogenesis of different inflammatory and tumor diseases of the oral cavity, these cells may become therapeutic targets that could possibly improve the prognosis and survival of these patients.

Elucidating drivers of oral epithelial dysplasia formation and malignant transformation to cancer using RNAseq

Oral squamous cell carcinoma (OSCC) is a prevalent cancer with poor prognosis. Most OSCC progresses via a non-malignant stage called dysplasia. Effective treatment of dysplasia prior to potential malignant transformation is an unmet clinical need. To identify markers of early disease, we performed RNA sequencing of 19 matched HPV negative patient trios: normal oral mucosa, dysplasia and associated OSCC. We performed differential gene expression, principal component and correlated gene network analysis using these data. We found differences in the immune cell signatures present at different disease stages and were able to distinguish early events in pathogenesis, such as upregulation of many HOX genes, from later events, such as down-regulation of adherens junctions. We herein highlight novel coding and non-coding candidates for involvement in oral dysplasia development and malignant transformation, and speculate on how our findings may guide further translational research into the treatment of oral dysplasia.

Three Novel Alkaloids from Portulaca oleracea L. and Their Anti-inflammatory Effects

Three novel carbon skeleton alkaloids, named oleracimine (1), oleracimine A (2), and oleracone A (3), with one novel azulene carbon skeleton compound, oleracone B (4), and one known compound, β-carboline (5), were first isolated from Portulaca oleracea L. The structures were determined using spectroscopic methods, including one- and two-dimensional nuclear magnetic resonance and high-resolution electrospray ionization time-of-flight mass spectrometry techniques. In addition, oleracimine (1) was used to investigate the anti-inflammatory effects on lipopolysaccharide-stimulated macrophages. The results of enzyme-linked immunosorbent assay, western blot, and real-time polymerase chain reaction showed that oleracimine (1) remarkably inhibited nitric oxide production and could dose-dependently decrease the secretions of interleukin 6, tumor necrosis factor α, nitric oxide, and prostaglandin E2 in cell culture supernatants as well as the mRNA of cyclooxygenase-2 and inducible nitric oxide synthase.

Antimicrobial agent triclosan is a proton ionophore uncoupler of mitochondria in living rat and human mast cells and in primary human keratinocytes

Triclosan (TCS) is an antimicrobial used widely in hospitals and personal care products, at ~10 mm. Human skin efficiently absorbs TCS. Mast cells are ubiquitous key players both in physiological processes and in disease, including asthma, cancer and autism. We previously showed that non-cytotoxic levels of TCS inhibit degranulation, the release of histamine and other mediators, from rat basophilic leukemia mast cells (RBL-2H3), and in this study, we replicate this finding in human mast cells (HMC-1.2). Our investigation into the molecular mechanisms underlying this effect led to the discovery that TCS disrupts adenosine triphosphate (ATP) production in RBL-2H3 cells in glucose-free, galactose-containing media (95% confidence interval EC50 = 7.5-9.7 µm), without causing cytotoxicity. Using these same glucose-free conditions, 15 µm TCS dampens RBL-2H3 degranulation by 40%. The same ATP disruption was found with human HMC-1.2 cells (EC50 4.2-13.7 µm), NIH-3 T3 mouse fibroblasts (EC50 4.8-7.4 µm) and primary human keratinocytes (EC50 3.0-4.1 µm) all with no cytotoxicity. TCS increases oxygen consumption rate in RBL-2H3 cells. Known mitochondrial uncouplers (e.g., carbonyl cyanide 3-chlorophenylhydrazone) previously were found to inhibit mast cell function. TCS-methyl, which has a methyl group in place of the TCS ionizable proton, affects neither degranulation nor ATP production at non-cytotoxic doses. Thus, the effects of TCS on mast cell function are due to its proton ionophore structure. In addition, 5 µm TCS inhibits thapsigargin-stimulated degranulation of RBL-2H3 cells: further evidence that TCS disrupts mast cell signaling. Our data indicate that TCS is a mitochondrial uncoupler, and TCS may affect numerous cell types and functions via this mechanism. Copyright © 2015 John Wiley & Sons, Ltd.

Correlation of mast cells in different stages of human periodontal diseases: Pilot study

AIMS AND OBJECTIVES

The aim of this study was to evaluate and correlate the relationship between mast cells counts and different stages of human periodontal diseases.

MATERIALS AND METHODS

The study sample comprised 50 patients, which were divided into three groups, consisting of 10 cases of clinically healthy gingival tissues (control group) 20 cases of dental plaque-induced gingivitis with no attachment loss and 20 cases of localized chronic periodontitis (LCP) characterized by the loss of periodontal support. The samples for control group were obtained during tooth extractions for orthodontic reasons. The specimens were immediately fixed in 10% neutral buffered formalin.

CONCLUSION

In this study, LCP cases had higher mast cell counts compared to gingivitis sites or healthy tissues. Increased mast cell counts in the progressing sites of periodontal diseases may indicate the importance of these cells in the progression of chronic periodontitis.

Altered immunohistochemical expression of mast cell tryptase and chymase in the pathogenesis of oral submucous fibrosis and malignant transformation of the overlying epithelium

Mast cells (MCs) expressing serine proteases; tryptase and chymase, are associated with fibrosis in various diseases. However, little is known about their involvement in oral submucous fibrosis (OSF). Our goal was to evaluate the role of MC tryptase and chymase in the pathogenesis of OSF and its malignant transformation. Immunohistochemical expression of MC tryptase and chymase was evaluated in 20 cases of OSF, 10 cases of oral squamous cell carcinoma (OSCC) and 10 cases of healthy controls. Subepithelial zone of Stage 1 and 2 while deep zone of Stage 3 and 4 OSF demonstrated increased tryptase positive MCs. OSCC revealed a proportionate increase in tryptase and chymase positive MCs irrespective of areas of distribution. An altered balance in the subepithelial and deep distribution of tryptase and chymase positive MCs play an important role in the pathogenesis of OSF and its malignant transformation.

The anti-inflammatory effect of Indonesian Areca catechu leaf extract in vitro and in vivo

BACKGROUND/OBJECTIVES

Overproduction of nitric oxide (NO) by the inducible nitric oxide synthase (iNOS) enzyme can cause inflammation. Cyclooxygenase-2 (COX-2) is also involved in the inflammatory response through regulation of nuclear factor-kappa B (NF-κB). Areca catechu is one of the known fruit plants of the Palmaceae family. It has been used for a long time as a source of herbal medicine in Indonesia. In this study, we explored the effect of Indonesian Areca catechu leaf ethanol extract (ACE) in lipopolysaccharide (LPS)-induced inflammation and carrageenan-induced paw edema models. Recently, this natural extract has been in the spotlight because of its efficacy and limited or no toxic side effects. However, the mechanism underlying its anti-inflammatory effect remains to be elucidated.

MATERIALS/METHODS

We measured NO production by using the Griess reagent, and determined the expression levels of inflammation-related proteins, such as iNOS, COX2, and NF-κB, by western blot. To confirm the effect of ACE in vivo, we used the carrageenan-induced paw edema model.

RESULTS

Compared to untreated cells, LPS-stimulated RAW 264.7 cells treated with ACE showed reduced NO generation and reduced iNOS and COX-2 expression. We found that the acute inflammatory response was significantly reduced by ACE in the carrageenan-induced paw edema model.

CONCLUSION

Taken together, these results suggest that ACE can inhibit inflammation and modulate NO generation via downregulation of iNOS levels and NF-κB signaling in vitro and in vivo. ACE may have a potential medical benefit as an anti-inflammation agent.

A quantitative analysis of mast cells in inflammatory periapical and gingival lesions

AIM

The aim of the study was to quantify the presence of mast cells in various inflammatory lesions like periapical granuloma, periapical cyst, inflammatory gingival hyperplasia and pyogenic granuloma. Mast cell degranulation and association with lymphocytes were also recorded in an attempt to understand the role of mast cells in the pathogenesis of these inflammatory lesions.

MATERIALS AND METHODS

The quantification of mast cells was done on toluidine blue stained sections of all the four groups of lesions, using the image analyzer software, Image-Pro-Express (Media Cybernetics, USA).

RESULTS

An increased number of mast cells in various inflammatory lesions with a significant difference between the four groups were noted. Mast cell number tended to be greater in the lesions present in the anterior region of the mouth than in the posterior region of the oral cavity. The mean mast cell number decreased with the increasing age which was directly correlated with the age of the patients. Mast cell site, distribution, degranulation and its association with fibroblasts, lymphocytes and blood vessels were noted.

CONCLUSION

The location of mast cells in different areas, their association with lymphocytes, fibroblasts, endothelial cells, and the phenomenon of degranulation helps to appreciate the release of various mediators and multiple interactions among these cells, leading to increased vascular permeability, angiogenic response, collagen synthesis, regulation of inflammation, bone resorption, and extracellular matrix destruction, thus contributing to the pathogenesis of these inflammatory lesions.

Oral lichen planus and neurogenic inflammation: new observations and therapeutic implications from four clinical cases

Oral lichen planus (OLP) is a usually chronic and relapsing mucocutaneous disease with unknown etiology. Immunosuppressive treatment is sometimes unsatisfactory. We describe four cases of reticular OLP localized on the internal side of cheek, in the territory innervated by sensory free endings of the buccinator nerve, poorly responding to immunosuppressive treatment (topical/systemic corticosteroids, topical cyclosporin). Addition of prazepam 10 mg/day to standard therapy achieved significant improvement and clinical healing in 30-40 days. Because of the complex interplay between the nervous and immune systems, neuroinflammation, acting through conventional axon reflex and/or indirect reflex mechanism involving localized efferent vasodilatory parasympathetic fibers, could have an important pathogenic role in OLP. Such hypothesis could explain, at least partly, the spreading of lesions in OLP primarily triggered (and possibly sustained) by infections, irritants, or autoimmunity. Moreover, neuroinflammation could have a relevant role in OLP related to psychosomatic diseases, where the nervous component is the primary trigger and the main pathogen responsible for the lesions observed. Benzodiazepines modulate neuroinflammation through central, and, possibly, peripheral action. In OLP patients with mild/subclinical psychological conditions, low doses may effectively modulate neuroinflammatory pathways that are not always completely inhibited by immunosuppressive treatment and can contribute to the persistence of inflammation.

Effect of crataegus usage in cardiovascular disease prevention: an evidence-based approach

Hawthorn (Crataegus oxyacantha) is a widely used Chinese herb for treatment of gastrointestinal ailments and heart problems and consumed as food. In North America, the role of treatment for heart problems dates back to 1800. Currently, evidence is accumulating from various in vivo and in vitro studies that hawthorn extracts exert a wide range of cardiovascular pharmacological properties, including antioxidant activity, positive inotropic effect, anti-inflammatory effect, anticardiac remodeling effect, antiplatelet aggregation effect, vasodilating effect, endothelial protective effect, reduction of smooth muscle cell migration and proliferation, protective effect against ischemia/reperfusion injury, antiarrhythmic effect, lipid-lowering effect and decrease of arterial blood pressure effect. On the other hand, reviews of placebo-controlled trials have reported both subjective and objective improvement in patients with mild forms of heart failure (NYHA I-III), hypertension, and hyperlipidemia. This paper discussed the underlying pharmacology mechanisms in potential cardioprotective effects and elucidated the clinical applications of Crataegus and its various extracts.

Trigeminal nerve stimulation triggers oral mast cell activation and vascular permeability

BACKGROUND

The nervous system contributes to the pathophysiology of allergic and inflammatory diseases, including oral inflammation. Mast cells (MCs) are involved in their pathogenesis through proinflammatory mediator release.

OBJECTIVE

To investigate the effect of trigeminal nerve (TN) stimulation compared with sham operation on MC activation and oral vascular permeability in the gingiva, palate, buccal mucosa, and tongue of the rat and to examine the possible role of substance P using rats treated with capsaicin as neonates to deplete substance P.

METHODS

Six male Sprague-Dawley rats (250 g) were anesthetized and injected intravenously with Evans Blue (EB). Six other rats were injected neonatally with capsaicin (n = 3) or solvent (n = 3) and then injected with EB when they reached 250 g. The mandibular branch of the TN was stimulated for 1 minute (n = 3), and the remaining rats (n = 3) were subjected to sham operation. The ipsilateral and contralateral sides of the mouth were examined for EB extravasation, and tissue sections were removed for light and electron microscopy.

RESULTS

TN stimulation resulted in EB extravasation in the ipsilateral side compared with the contralateral side or the ipsilateral side of sham-operated rats. Significant degranulation of MCs also was evident only on the ipsilateral side (P < .0001). There was no difference in MC degranulation between the vehicle- and capsaicin-treated rats, implying that neuropeptides other than substance P may be involved.

CONCLUSION

This is the first time that TN stimulation has been shown to result in MC activation and oral vascular permeability, suggesting that MC inhibitors may be used for the treatment of oral inflammatory diseases.

In silico analysis and experimental validation of molecular mechanisms of salvianolic acid A-inhibited LPS-stimulated inflammation, in RAW264.7 macrophages

OBJECTIVES

The aim of this study was to explore mechanisms by which salvianolic acid A (SAA) revealed its anti-inflammatory activity, in lipopolysaccharide (LPS)-stimulated RAW264.7 cells.

MATERIALS AND METHODS

Nitric oxide (NO) concentration was determined by the Griess reaction and cell viability was assessed by MTT assay. Interleukin-6, TNFα and interleukin-1β were determined by ELISA. The RAW264.7 cells were transfected with siRNA against p38 or HO-1. Expressions of COX-2, inducible NO synthase (iNOS), NF-κB, HO-1, p-p38 and phosphorylation of IκB kinase α/β were detected by western blotting. Potential targets of SAA were analysed by homology modelling, target prediction, protein-protein interaction prediction and docking studies.

RESULTS

Salvianolic acid A suppressed LPS-triggered production of NO, TNFα and Interleukin-6. It also reduced protein expression of inducible NO synthase and COX-2, and reduced translocation of NF-κB to nuclei. Moreover, SAA promoted expression of phosphorylated p38, and downstream HO-1. Zn (II) protoporphyrin IX, a specific inhibitor of HO-1, or siRNA against HO-1 could effectively increase transfer of NF-κB. SAA was predicted to target amyloid-beta protein-like protein and arachidonate 5-lipoxygenase, that could regulate p38 and HO-1.

CONCLUSIONS

In silico analysis and experimental validation together demonstrated that SAA exhibited its anti-inflammatory effect via the p38-HO-1 pathway in LPS-stimulated RAW264.7 cells, reduced transfer of NF-κB to the nuclei and thus reduced production of inflammatory mediators.