Interstitial fluid drainage from rat apical area takes place via vessels in the mandibular canal.

We sought to investigate the transport route for protein‐rich fluid from the apical area towards the draining lymph nodes. The first mandibular molar root canals in 24 female Wistar rats were instrumented and filled with radioactive‐labelled human serum albumin. The rats were sacrificed at different intervals beginning after 10 min (time 0) and continuing up to 72 h. Three jaw segments, gingiva around the first molar, blood samples, submandibular and cervical lymph nodes were collected and analyzed for radioactivity. The starting volume of tracer (control) for all experiments was calculated from measurements at time 0. At time 0, radioactivity was only detected in the jaw segments. Within lymph nodes and serum, the tracer was found after 4 h, with the highest amount recorded in serum up to 24 h. Lymphatics were found within the mandibular canal along blood vessels and nerves and exiting via foramen mandibularis, after immunohistochemical staining in four untreated rats. Our results show tracer distribution from the apical area towards the mandibular canal in a posterior direction. The tracer washout rate was low, and the fluid was mainly absorbed into blood vessels. The lymphatics in the mandibular canal may be more important for immune cell transport than for fluid drainage.publishedVersio

Human gingival epithelial cells stimulate proliferation, migration, and tube formation of lymphatic endothelial cells in vitro

Objective The aim of this study was to investigate the response of gingival epithelial cells to microbial and inflammatory signals. Background The gingival epithelial barrier provides the first line of defense and supports tissue homeostasis by maintaining the cross-talk between gingival epithelium, oral microbiota, and immune cells. Lymphatic vessels are essential to sustaining this homeostasis. The gingival epithelial cells have been shown to produce prolymphangiogenic factors during physiologic conditions, but their role in response to microbial and inflammatory signals is unknown. Methods Immortalized human gingival epithelial cells (HGEC) and human dermal lymphatic microvascular endothelial cells (LEC) were cultured. HGEC were exposed to Porphyromonas gingivalis derived-LPS, human IL-1 beta/IL-1F2 protein, or recombinant human IL-6/IL-6R. Levels of vascular growth factors (VEGF-A, VEGF-C, and VEGF-D) in cell supernatants were determined by ELISA. LEC were grown to confluence, and a scratch was induced in the monolayer. Uncovered area was measured up to 48 h after exposure to conditioned medium (CM) from HGEC. Tube formation assays were performed with LEC cocultured with labelled HGEC or exposed to CM. Results VEGF-A, VEGF-C, and low levels of VEGF-D were constitutively expressed by HGEC. The expression of VEGF-C and VEGF-D, but not VEGF-A, was upregulated in response to proinflammatory mediators. VEGF-C was upregulated in response to P. gingivalis LPS, but not to Escherichia coli LPS. A scratch migration assay showed that LEC migration was significantly increased by CM from HGEC. Both the CM and coculture with HGEC induced significant tube formation of LEC. Conclusions HGEC can regulate production of lymphangiogenic/angiogenic factors during inflammatory insults and can stimulate proliferation, migration, and tube formation of LEC in vitro in a paracrine manner.publishedVersio

Algorithm of diagnosis and treatment of thrombophilia in pregnancy – the experience of the obstetrics-gynecology department of the emergency university hospital Bucharest

University Emergency Hospital, Dept of Ob/Gyn, Bucharest, Romania, Al VI-lea Congres Național de Obstetrică și Ginecologie cu participare internațională, 13-15 septembrie 2018, Chișinău, Republica MoldovaThrombophilias defines a group of disorders associated with an increased tendency for thrombosis. They may also be seen as a heterogeneous group of conditions that have been associated during time with a variety of pregnancy complications, including early and late fetal loss, intrauterine fetal death, placental abruption, poor fetal growth (IUGR) and preeclampsia. Our clinical retrospective study was performed between 1st January 2006 and 30th June 2008. We evaluated 11518 pregnant women, who delivered in our Clinic, out of which 254 (2.20%) had different types of thrombophilias: antiphospholipid antibody syndrome (62.20%), factor V Leiden (16.93%), protein S deficiency (14.17%), protein C deficiency (3.94%), antithrombin III deficiency (2.76%). Preeclampsia was present at 27.17% of patients, out of which most cases were recorded in the APLS (36.08%), followed by APCR (30%) and the protein S deficiency (8.33%). There were mild forms of preeclampsia and they occurred in the patients who started treatment late (after the 26th week of pregnancy, due to the moment of diagnosis). Fetal pathology was represented by IUGR (20.47%) and premature birth (11.81%). The health condition of newborns, expressed by the Apgar index was very good in most of the cases (IA=10: 8.66%, IA=9: 71.26%, IA=8: 14.96%, IA=7: 3.94%, IA-6: 1.18%). The favorable evolution of the fetuses was due to the early diagnosis established and the proper treatment administrated. We had no fetal death in the group of diagnosed and treated thrombophilia patients, as well as no other thromboembolic complication. In a conclusion, we think that there are several important issues that should be taken into account when managing a pregnant thrombophilic woman. It is of great importance: • To think that pregnancy is a state of acquired hypercoagulability and that women hiding a thrombophilia may present with clinical symptoms for the first time during gestation or the puerperium – so think THROMBOPHILIA. � To correctly select the patients for thrombophilia testing. � To choose the correct moment for testing. � To provide thromboprophylaxis before the occurrence of any obstetrical complication mentioned above. � To judge correctly especially during the second half of pregnancy the ultrasonic appearance of the placenta, the growth curves of the fetus, and the placental circulation, elements that can modulate the management of that pregnancy (modifying the dosage of anticoagulant, establishing the right time for delivery)

Vascular endothelial growth factors and receptors - from normal dental pulp to apical pathology

The VEGFs -A, -B, -C, -D are important signaling molecules with pivotal implication in the growth of blood and lymphatic vessels, the so-called angio- and lymphangiogenesis. They exert their activities by binding to their receptors, VEGFRs-1, -2 and -3. Their involvement in pathologic processes such as tumor growth or inflammatory disorders has been thoroughly described, rheumatoid arthritis being just one example. The VEGF family represents the link between angiogenesis and bone turnover, as seen in cancer metastasis to the bone or arthritis. Furthermore, they are involved in the differentiation of dendritic cells and lymphocytes, while macrophages and PMNs have been identified as sources of VEGFs, showing a mediatory function of these molecules in immune responses. The presence of VEGF-A and its main angiogenic receptor VEGFR-2 in well- vascularized normal dental pulp has been previously described. Apical periodontitis, a common inflammatory disease caused by the interaction of root canal bacteria with the host immune response, is characterized by bone resorption. VEGF-A is also known to be present in these lesions of endodontic origin. However, the picture of VEGF family and their receptors with respect to location and function in the dental pulp and in periapical pathology have so far been incomplete. The aims of this thesis were to identify and map the presence of VEGF family and their receptors VEGFR-2 and -3 in apical periodontitis and dental pulp and to investigate their role in periapical disease development. In normal rat apical periodontium (Paper I), VEGF-A, -C, -D and VEGFR-2 and -3 were present on blood vessels. Upon endodontic exposure for periapical disease development, an intensification of immunohistochemically stained vascular structures was noticed. Macrophages and neutrophils expressed all VEGFs and VEGFRs in the lesions, with macrophages being an important source of VEGF-C and -D. Osteoclasts were the source for VEGFR-2 and -3. The gene expression of VEGF-A and VEGFR- 3 was significantly up-regulated following pulp exposure. The results suggest the implication of VEGF family and their receptors in the periapical immune response, vascular remodeling and in bone resorptive activities. In human periapical lesions (Paper II) VEGFs and VEGFRs were expressed on blood vessels and on macrophages, PMNs, B- and T-lymphocytes. At the gene level, significant up-regulations were recorded for genes involved in VEGF-mediated angiogenic activity, such as phosphatidylinositol-3-kinases (Pl3K), protein kinase C (PKC), mitogen-activated protein kinases (MAPK) and phospholipases (PL). These findings suggest the implication of VEGF family in ongoing immune reactions along with vascular remodeling in human established periapical lesions. The normal dental pulp (Paper III) presented with blood vessels, macrophages and T- lymphocytes positive for the same VEGFs and VEGFRs. Furthermore, VEGF-B was only seen at cellular level in the dental pulp. Twenty-six of 84 VEGF signaling genes, including VEGFR-3 were significantly altered in the dental pulp compared with control PDL. The pulpal tissue has high VEGF signaling capacity with respect to immune responses and vascular activity. Using specific markers for lymphatic vessels, we confirmed the absence of lymphatic vessels from both apical periodontium and the dental pulp. Macrophages expressing LYVE-1 were found in human periapical lesions and the dental pulp, with an assumed angiogenic role. Upon inducing periapical lesions we systemically blocked VEGFR-2 and/or -3 in order to investigate their signaling patterns with respect to lesion size, angiogenesis, local inflammatory response and lymphangiogenesis in the draining lymph nodes (Paper IV). We have found that VEGFR-2 reduces inflammation whereas combined VEGFR-2 and -3 signaling causes an increase of the process, seen in amounts of PMNs and osteoclasts, as well as different cytokines expression. In the regional lymph nodes, lymphangiogenesis is dependent on VEGFR-2 and/or VEGFR-3 signaling. The results of these studies provide evidence on the presence of VEGFs and VEGFRs in dental pulp and apical periodontitis, with implications in immune responses and vascular remodeling. VEGFR-2 and/or -3 signaling influences inflammatory reactions during periapical disease development

Fluid transport from the dental pulp revisited.

In the dental pulp surrounded by rigid dentinal walls, an increase in fluid volume will be followed by a rapid increase in interstitial fluid pressure. To maintain pressure homeostasis, a fluid drainage system is required. The dental pulp and apical periodontal ligament lack lymphatic vessels, and the questions are how the transport can take place inside the pulp and where the lymphatic vessels draining fluid from the apical periodontal ligament are located. The drainage of fluid within the pulp must be governed by a tissue pressure gradient (driving pressure) and the fluid is likely transported in loose connective tissue (gaps) surrounding vessels and nerve fibers. We suggest that aging of the pulp tissue characterized by fibrosis will reduce the draining capacity and make it more vulnerable to circulatory failure. When the fluid leaves the pulp, it will follow the nerve bundles and vessels through the periapical ligament into bone channels, where lymphatic vessels are found. In the mandibular canal, lymphatic vessels are localized and the fluid washout rate from the canal is slow, but chewing may speed it up by increasing the fluid pressure. In acute apical periodontitis, inflammatory mediators and bacterial components can be spread to regional lymph nodes via lymphatic vessels inside the jaw bone

VEGFR-2 reduces while combined VEGFR-2 and -3 signaling increases inflammation in apical periodontitis

Background: In apical periodontitis, oral pathogens provoke an inflammatory response in the apical area that induces bone resorptive lesions. In inflammation, angio- and lymphangiogenesis take place. Vascular endothelial growth factors (VEGFs) and their receptors (VEGFRs) are key players in these processes and are expressed in immune cells and endothelial cells in the lesions. Objective: We aimed at testing the role of VEGFR-2 and -3 in periapical lesion development and investigated their role in lymphangiogenesis in the draining lymph nodes. Design: We induced lesions by pulp exposure in the lower first molars of C57BL/6 mice. The mice received IgG injections or blocking antibodies against VEGFR-2 (anti-R2), VEGFR-3 (anti-R3), or combined VEGFR-2 and -3, starting on day 0 until day 10 or 21 post-exposure. Results: Lesions developed faster in the anti-R2 and anti-R3 group than in the control and anti-R2/R3 groups. In the anti-R2 group, a strong inflammatory response was found expressed as increased number of neutrophils and osteoclasts. A decreased level of pro-inflammatory cytokines was found in the anti-R2/R3 group. Lymphangiogenesis in the draining lymph nodes was inhibited after blocking of VEGFR-2 and/or -3, while the largest lymph node size was seen after anti-R2 treatment. Conclusions: We demonstrate an anti-inflammatory effect of VEGFR-2 signaling in periapical lesions which seems to involve neutrophil regulation and is independent of angiogenesis. Combined signaling of VEGFR-2 and -3 has a pro-inflammatory effect. Lymph node lymphangiogenesis is promoted through activation of VEGFR-2 and/or VEGFR-3

Biomarkers common for inflammatory periodontal disease and depression: A systematic review

Background Dysregulated immune response arising in the periphery can induce depressive symptoms through neuroimmune interactions. Inflammatory oral pathology can be a potent inducer of chronic neuroimmune response relevant to depression. We aimed to synthesize available evidence for the association between inflammatory periodontal diseases (IPD) and major depression (MD) in relation to a broad range of biomarkers. Methods Medline, Embase, PsycInfo, Cochrane Library, Web of Science and Scopus databases were searched from inception until January 27, 2022. Search terms included subject headings and synonyms for inflammatory periodontal disease and depression. Studies that reported data on both depression and inflammatory periodontal disease as categories along with measurement of a biomarker were considered. Two reviewers independently selected the articles for inclusion, extracted data and assessed the quality of each study. The protocol for this study was registered with PROSPERO, CRD42021215524. Results Twenty-eight studies were included in the final review-eleven cross-sectional studies, seven case-control studies, and six prospective cohort studies conducted in humans; the remaining four were experimental animal studies. Eighteen studies including all animal studies reported a positive association between depression and periodontal disease; one study reported a negative association and another nine studies found no such associations. Twenty studies reported mixed associations between IPD and biomarkers (i.e, salivary, serum, urine or gingival crevicular fluid cortisol, C reactive protein, cytokines, etc.). Biomarkers related to depression were gingival crevicular fluid cortisol, interleukin 6 (IL-6), Il-1β, immunoglobulin G against Bacterioides forsythus; root canal lipopolysaccharides; blood IL-6, IL-1β, cortisol, advanced oxidation protein products, nitric oxide metabolites, lipid hydroperoxides and trapping antioxidant parameter; whereas five studies found no associations between depression and a biomarker. Although animal studies showed interaction of immune, inflammatory and neurotrophic biomarkers in the relationship between depression and periodontal disease, human studies showed mixed findings. In most studies, there were risks of bias due to the sample selection and assessment protocol. Study heterogeneity and limited number of comparable studies reporting on shared biomarkers precluded a meta-analysis. Conclusion Immune-inflammatory contribution to depression was evident in the context of inflammatory periodontal diseases, but whether biomarkers mediate the associations between IPD and MD needs to be tested through methodologically rigorous studies aiming specifically at this hypothesis