Anna Földes - Academia.edu (original) (raw)

Papers by Anna Földes

International Journal of Molecular Sciences

Chronic periodontitis is a bacterial infection associated with dentally adherent biofilm (plaque)... more Chronic periodontitis is a bacterial infection associated with dentally adherent biofilm (plaque) accumulation and age-related comorbidities. The disease begins as an inflammatory exudate from gingival margins, gingival crevicular fluid (GCF) in response to biofilm lysine. After a week of experimental gingivitis (no oral hygiene), biofilm lysine concentration was linearly related to biofilm accumulation (plaque index) but to GCF as an arch-shaped double curve which separated 9 strong from 6 weak GCF responders (hosts). Host DNA was examined for single nucleotide polymorphisms (SNPs) of alleles reported in 7 periodontitis-associated genes. Across all 15 hosts, an adenine SNP (A) at IL1B-511 (rs16944), was significant for strong GCF (Fisher’s exact test, p < 0.05), and a thymidine SNP (T) at IL1B+3954 (rs1143634) for weak GCF provided 2 hosts possessing IL6-1363(T), rs2069827, were included. The phenotype of IL1B+3954(T) was converted from weak to strong in one host, and of the non...

The Journal of Neuroscience

Materials

Journal of Periodontal Research, 2020

Background and ObjectivePeriodontal ligament cells (PDLCs) are an important source for periodonta... more Background and ObjectivePeriodontal ligament cells (PDLCs) are an important source for periodontal tissue healing and regeneration. Proper cell adhesion is a key for survival of anchorage‐dependent cells and also initiates further intracellular signals for essential cellular functions. We aimed to test 3 different synthetic conjugates with integrin‐binding RGD sequence (SAK‐c[RGDfC], AK‐c[RGDfC], and SAK‐opn on the adhesion of human PDLCs and subsequent events including proliferation, migration, behavior of cell surface molecules, and osteogenic differentiation.Materials and MethodsSynthetic peptides were synthesized by solid‐phase technique and attached to branched chain polymeric polypeptides via thioether linkage. Simple adsorption method was used to coat tissue culture plastic or electric arrays. PDLCs were isolated from 24 surgically extracted human third molars. Cell adhesion and proliferation were measured with real‐time impedimetric xCELLigence SP system. Cell migration assa...

Journal of physiology and pharmacology : an official journal of the Polish Physiological Society, 2014

Frontiers in Pharmacology, Jun 2, 2021

Background: Amelogenesis, the formation of dental enamel, is well understood at the histomorpholo... more Background: Amelogenesis, the formation of dental enamel, is well understood at the histomorphological level but the underlying molecular mechanisms are poorly characterized. Ameloblasts secrete enamel matrix proteins and Ca 2+ , and also regulate extracellular pH as the formation of hydroxyapatite crystals generates large quantities of protons. Genetic or environmental impairment of transport and regulatory processes (e.g. dental fluorosis) leads to the development of enamel defects such as hypomineralization. Aims: Our aims were to optimize the culture conditions for the three-dimensional growth of ameloblast-derived HAT-7 cells and to test the effects of fluoride exposure on HAT-7 spheroid formation. Methods: To generate 3D HAT-7 structures, cells were dispersed and plated within a Matrigel extracellular matrix scaffold and incubated in three different culture media. Spheroid formation was then monitored over a two-week period. Ion transporter and tight-junction protein expression was investigated by RT-qPCR. Intracellular Ca 2+ and pH changes were measured by microfluorometry using the fluorescent dyes fura-2 and BCECF. Results: A combination of Hepato-STIM epithelial cell differentiation medium and Matrigel induced the expansion and formation of 3D HAT-7 spheroids. The cells retained their epithelial cell morphology and continued to express both ameloblast-specific and ion transport-specific marker genes. Furthermore, like two-dimensional HAT-7 monolayers, the HAT-7 spheroids were able to regulate their intracellular pH and to show intracellular calcium responses to extracellular stimulation. Finally, we demonstrated that HAT-7 spheroids may serve as a disease model for studying the effects of fluoride exposure during amelogenesis. Conclusion: In conclusion, HAT-7 cells cultivated within a Matrigel extracellular matrix form three-dimensional, multi-cellular, spheroidal structures that retain their functional capacity for pH regulation and intracellular Ca 2+ signaling. This new 3D model will allow us to gain a better understanding of the molecular mechanisms involved in amelogenesis, not

Journal of Dental Research, Jan 20, 2016

Formation and growth of hydroxyapatite crystals during amelogenesis generate a large number of pr... more Formation and growth of hydroxyapatite crystals during amelogenesis generate a large number of protons that must be neutralized, presumably by HCO 3 − ions transported from ameloblasts into the developing enamel matrix. Ameloblasts express a number of transporters and channels known to be involved in HCO 3 − transport in other epithelia. However, to date, there is no functional evidence for HCO 3 − transport in these cells. To address questions related to HCO 3 − export from ameloblasts, we have developed a polarized 2-dimensional culture system for HAT-7 cells, a rat cell line of ameloblast origin. HAT-7 cells were seeded onto Transwell permeable filters. Transepithelial resistance was measured as a function of time, and the expression of transporters and tight junction proteins was investigated by conventional and quantitative reverse transcription polymerase chain reaction. Intracellular pH regulation and HCO 3 − transport were assessed by microfluorometry. HAT-7 cells formed epithelial layers with measureable transepithelial resistance on Transwell permeable supports and expressed claudin-1, claudin-4, and claudin-8-key proteins for tight junction formation. Transport proteins previously described in maturation ameloblasts were also present in HAT-7 cells. Microfluorometry showed that the HAT-7 cells were polarized with a high apical membrane CO 2 permeability and vigorous basolateral HCO 3 − uptake, which was sensitive to Na + withdrawal, to the carbonic anhydrase inhibitor acetazolamide and to H 2 DIDS inhibition. Measurements of transepithelial HCO 3 − transport showed a marked increase in response to Ca 2+-and cAMP-mobilizing stimuli. Collectively, 2-dimensional HAT-7 cell cultures on permeable supports 1) form tight junctions, 2) express typical tight junction proteins and electrolyte transporters, 3) are functionally polarized, and 4) can accumulate HCO 3 − ions from the basolateral side and secrete them at the apical membrane. These studies provide evidence for a regulated, vectorial, basolateral-to-apical bicarbonate transport in polarized HAT-7 cells. We therefore propose that the HAT-7 cell line is a useful functional model for studying electrolyte transport by ameloblasts.

Cellular Reprogramming, Feb 1, 2023

Mesenchymal stem/stromal cells (MSCs) are found in almost all postnatal organs. Under appropriate... more Mesenchymal stem/stromal cells (MSCs) are found in almost all postnatal organs. Under appropriate environmental cues, multipotency enables MSCs to serve as progenitors for several lineage-specific, differentiated cell types. In vitro expansion and differentiation of MSCs give the opportunity to obtain hardly available somatic cells, such as neurons. The neurogenic potential of MSCs makes them a promising, autologous source to restore damaged tissue and as such, they have received much attention in the field of regenerative medicine. Several stem cell pool candidates have been studied thus far, but only a few of them showed neurogenic differentiation potential. Due to their embryonic ontology, stem cells residing in the stroma of the dental pulp chamber are an exciting source for in vitro neural cell differentiation. In this study, we review the key properties of dental pulp stem cells (DPSCs), with a particular focus on their neurogenic potential. Moreover, we summarize the various presently available methods used for neural differentiation of human DPSCs also emphasizing the difficulties in reproducibly high production of such cells. We postulate that because DPSCs are stem cells with very close ontology to neurogenic lineages, they may serve as excellent targets for neuronal differentiation in vitro and even for direct reprogramming.

PubMed, Jun 1, 2014

Periodontitis is a chronic inflammatory disease leading to alveolar bone destruction, and eventua... more Periodontitis is a chronic inflammatory disease leading to alveolar bone destruction, and eventually tooth loss. In genetically or environmentally predisposed individuals periodontopathogenic bacteria trigger an inflammatory immune response where activated macrophages secrete inflammatory cytokines and T helper 17 cells produce interleukin-17, receptor activator of nuclear factor kappa B ligand (RANKL) and tumor necrosis factor-α. Inflammation and the production of RANKL, the key cytokine responsible for osteoclast activation, cause excessive activation of osteoclasts. This results in a decoupling between bone formation and resorption, leading to bone loss. As conventional treatment does not target the inflammatory response and osteoclast activation, its effectiveness is limited. Novel treatments are thus required if we are to cure this disease. Mesenchymal stem cells (MSCs), including those of dental origin, are potent immunomodulators and are known to be suitable for tissue regeneration. MSCs can inhibit the immune response by suppressing T cells, inducing regulatory T cells and converting dendritic cells and macrophages into a regulatory phenotype. Additionally, genetic modulation may enhance the therapeutic potential of MSCs. In the present review the authors describe the potential use of MSCs, either unmodified or engineered for therapeutic purposes in periodontitis, with special emphasis on MSCs from dental pulp and periodontal ligament. The paper envisions that multiple targeting of this inflammatory disease by modulating the immune response, promoting bone regeneration and inhibiting bone resorption might yield significantly improved treatment outcomes when combined with conventional treatment modalities.

Materials, Aug 6, 2020

Background: Triethylene glycol dimethacrylate (TEGDMA) monomers released from resin matrix are to... more Background: Triethylene glycol dimethacrylate (TEGDMA) monomers released from resin matrix are toxic to dental pulp cells, induce apoptosis, oxidative stress and decrease viability. Recently, mitochondrial complex I (CI) was identified as a potential target of TEGDMA. In isolated mitochondria supported by CI, substrates oxidation and ATP synthesis were inhibited, reactive oxygen species production was stimulated. Contrary to that, respiratory Complex II was not impaired by TEGDMA. The beneficial effects of electron carrier compound methylene blue (MB) are proven in many disease models where mitochondrial involvement has been detected. In the present study, the bioenergetic effects of MB on TEGDMA-treated isolated mitochondria and on human dental pulp stem cells (DPSC) were analyzed. Methods: Isolated mitochondria and DPSC were acutely exposed to low millimolar concentrations of TEGDMA and 2 µM concentration of MB. Mitochondrial and cellular respiration and glycolytic flux were measured by high resolution respirometry and by Seahorse XF extracellular analyzer. Mitochondrial membrane potential was measured fluorimetrically. Results: MB partially restored the mitochondrial oxidation, rescued membrane potential in isolated mitochondria and significantly increased the impaired cellular O 2 consumption in the presence of TEGDMA. Conclusion: MB is able to protect against TEGDMA-induced CI damage, and might provide protective effects in resin monomer exposed cells.

The Journal of Neuroscience, Dec 23, 2022

Stress disorders impair sleep and quality of life; however, their pathomechanisms are unknown. Pr... more Stress disorders impair sleep and quality of life; however, their pathomechanisms are unknown. Prolactin-releasing peptide (PrRP) is a stress mediator; we therefore hypothesized that PrRP may be involved in the development of stress disorders. PrRP is produced by the medullary A1/A2 noradrenaline (NA) cells, which transmit stress signals to forebrain centers, and by non-NA cells in the hypothalamic dorsomedial nucleus. We found in male rats that both PrRP and PrRP-NA cells innervate melanin-concentrating hormone (MCH) producing neurons in the dorsolateral hypothalamus (DLH). These cells serve as a key hub for regulating sleep and affective states. Ex vivo, PrRP hyperpolarized MCH neurons and further increased the hyperpolarization caused by NA. Following sleep deprivation, intracerebroventricular PrRP injection reduced the number of REM sleep-active MCH cells. PrRP expression in the dorsomedial nucleus was upregulated by sleep deprivation, while downregulated by REM sleep rebound. Both in learned helplessness paradigm and after peripheral inflammation, impaired coping with sustained stress was associated with (1) overactivation of PrRP cells, (2) PrRP protein and receptor depletion in the DLH, and (3) dysregulation of MCH expression. Exposure to stress in the PrRP-insensitive period led to increased passive coping with stress. Normal PrRP signaling, therefore, seems to protect animals against stress-related disorders. PrRP signaling in the DLH is an important component of the PrRP's action, which may be mediated by MCH neurons. Moreover, PrRP receptors were downregulated in the DLH of human suicidal victims. As stress-related mental disorders are the leading cause of suicide, our findings may have particular translational relevance.

Journal of Physiology and Pharmacology, Dec 1, 2009

Salivary glands produce a HCO 3-rich fluid that is important for the neutral milieu in the upper ... more Salivary glands produce a HCO 3-rich fluid that is important for the neutral milieu in the upper gastrointestinal tract. The molecular mechanism of this secretion is poorly understood. Par-C10, an immortalized rat parotid acinar line, has been shown to secrete Clin response to Ca 2+-mobilizing stimuli. Our aim was to assess the capacity of polarized monolayers of Par-C10 cells to transport and secrete HCO 3-. Transepithelial electrolyte movement was evaluated by short-circuit current measurements. Intracellular pH (pH i) was measured by microfluorometry in cells loaded with BCECF. Monolayers of Par-C10 cells, grown on Transwell membranes, developed high transepithelial resistance and exhibited vectorial anion secretion which was activated by both ATP and forskolin. The currents were partially inhibited by bumetanide and by withdrawal of HCO 3indicating the dependence of ion movements on NKCC and on HCO 3ions, respectively. In HCO 3-free solutions the recovery of pH i from acid loading was abolished by EIPA. In the presence of HCO 3there was a strong EIPA-insensitive recovery from acid loading which was inhibited by H 2 DIDS. ATP and forskolin stimulated HCO 3efflux from the cells. Furthermore, HClwithdrawal experiments showed the presence of DNDS-sensitive basolateral anion exchange. In conclusion Par-C10 cells achieve transepithelial transport that is sensitive to both intracellular Ca 2+-and cAMP-dependent stimulation. We identified Na + /H + exchange, Na +-HCO 3cotransport and anion exchange at the basolateral side of the cells as being involved in intracellular pH regulation and vectorial HCO 3secretion. This cell line offers a good model for further studies to understand the molecular mechanisms of salivary HCO 3secretion.

Pancreatology, May 1, 2013

We observed fast and long-lasting ATP release in Capan-1 cells in response to hypotonic and mecha... more We observed fast and long-lasting ATP release in Capan-1 cells in response to hypotonic and mechanical stimuli. Exposure to extracellular alkaline pH caused a monophasic sustained increase in extracellular ATP concentrations; acidic pH caused a short release of ATP (n¼8,8). ATP release observed with addition of UTP (10 mM) and ionomycin (5 mM) were relatively slow. The bile acid chenodeoxycholate (CDC, 0.1-1 mM) induced high and fast ATP release (max 1.0AE0.3 mM/10 6 cells/ml). CDC is most likely acting through GPBAR1 and the receptor is expressed in Capan-1 cells. Conclusion: Together, our data show that various stimuli release ATP with different kinetics and this may indicate different releasing mechanisms. In low concentrations ATP can stimulate opening of Cland K þ channels and potentiate ductal fluid secretion. However, overstimulation may deplete the cells of ATP, partially via ATP release, and thereby contribute to pathological processes in pancreas.

Gels, 2022

Several types of promising cell-based therapies for tissue regeneration have been developing worl... more Several types of promising cell-based therapies for tissue regeneration have been developing worldwide. However, for successful therapeutical application of cells in this field, appropriate scaffolds are also required. Recently, the research for suitable scaffolds has been focusing on polymer hydrogels due to their similarity to the extracellular matrix. The main limitation regarding amino acid-based hydrogels is their difficult and expensive preparation, which can be avoided by using poly(aspartamide) (PASP)-based hydrogels. PASP-based materials can be chemically modified with various bioactive molecules for the final application purpose. In this study, dopamine containing PASP-based scaffolds is investigated, since dopamine influences several cell biological processes, such as adhesion, migration, proliferation, and differentiation, according to the literature. Periodontal ligament cells (PDLCs) of neuroectodermal origin and SH-SY5Y neuroblastoma cell line were used for the in vit...

Journal of Materials Research and Technology, 2022

Journal of Dental Research, 2016

Pancreatology, 2014

humidified incubator with different culture media (DMEM, CMRL ± antioxidant supplement), oxygen t... more humidified incubator with different culture media (DMEM, CMRL ± antioxidant supplement), oxygen tensions, and the use of inserts. Culture medium was changed at fixed intervals. Every 24 hours, two slices were collected, formaldehyde-fixed, and processed for light microscopy. Sections were assessed by two independent pathologists (CV, CFM) for tissue viability, which was scored as the percentage of preserved pancreatic tissue (acini, islets, ducts). Results: Optimized culture conditions were achieved with CMRL medium, 31% oxygen tension and the use of inserts. In this setting, pancreatic tissue slices could be cultured ex vivo for up to 4 days with good preservation of structural integrity and tissue viability (mean 77%). Conclusion: Organotypic culture provides a reproducible system for the study of all constituents of human pancreatic tissue in conditions that are close to the in vivo situation.

Pancreatology, 2013

Frontiers in Pharmacology