scholarly journals The secret behind peripheral inflammation and depression: The hypothalamus

2020 ◽  
Author(s):  
Bruno Pedraz Petrozzi ◽  
Carlo Blecker ◽  
Elena Neumann ◽  
Gebhard Sammer
Keyword(s):  
Mixed Models ◽  
Enzyme Linked Immunosorbent Assay ◽  
Resonance Spectroscopy ◽  
Peripheral Inflammation ◽  
Tnf Α ◽  
Ifn Γ ◽  
And Control ◽  
Hpa Axis Activity ◽  
Inflammatory Component

Abstract In recent years there has been increasing evidence of an inflammatory component due to overstimulation of the hypothalamic-pituitary-adrenals (HPA) in depression. The glutamate metabolites (glutamate and glutamine) are important metabolites that are involved in this stimulation. The aim of this study was to determine the concentrations of hypothalamic glutamate metabolites in depression and to investigate their relationship to peripheral inflammation. Participants with diagnosed depression (DE; n = 24) and control subjects without depression (HC; n = 25) were investigated. Hypothalamic glutamate metabolites were recorded using in vivo magnetic resonance spectroscopy. Peripheral cytokines (IL-6, TNF-α, IFN-γ and IL-1β) were assessed using Enzyme-Linked Immunosorbent Assay. For statistical analysis, generalized mixed models were computed using Poisson distributions and a log link function. The results show overall higher hypothalamic glutamate metabolites in DE compared to HC. High TNF-a and IL-1ß concentrations are associated with high hypothalamic glutamate metabolites in DE. These results provide initial evidence that, in depression, increased HPA axis activity is associated with peripheral inflammation favored by hypothalamic glutamate metabolites.

scholarly journals Hypothalamic Glutamine-Glutamate Metabolites and Peripheral Pro-Inflammatory Cytokines in Participants with Depression: A Case-Control Study

2020 ◽  
Author(s):  
Bruno Pedraz Petrozzi ◽  
Carlo Blecker ◽  
Elena Neumann ◽  
Gebhard Sammer
Keyword(s):  
Enzyme Linked Immunosorbent Assay ◽  
Resonance Spectroscopy ◽  
Peripheral Inflammation ◽  
Tnf Α ◽  
Ifn Γ ◽  
And Control ◽  
Pituitary Adrenal Axis ◽  
Inflammatory Component ◽  
Control Study

Abstract Background: In recent years, there has been increasing evidence of an inflammatory component due to overstimulation of the hypothalamic-pituitary-adrenal axis (HPAA) in depression. The glutamate metabolites (glutamate and glutamine) are important in this stimulation. The aim of this study was to determine the concentrations of hypothalamic glutamate metabolites in depression and to investigate their relationship to peripheral inflammation. Methods: Participants with diagnosed depression (DE; n = 24) and control subjects without depression (HC; n = 25) were investigated. Hypothalamic glutamate metabolites were recorded using in vivo magnetic resonance spectroscopy. Peripheral cytokines (IL-6, TNF-α, IFN-γ and IL-1β) were assessed using Enzyme-Linked Immunosorbent Assay. For statistical analysis, generalized mixed models were computed using Poisson distributions and a log link function. Results: The results show overall higher hypothalamic glutamate metabolites in DE compared to HC. High TNF-α and IL-1β concentrations are associated with high hypothalamic glutamate metabolites in DE. Conclusions: These results provide initial evidence that, in depression, increased HPAA activity is associated with peripheral inflammation favored by hypothalamic glutamate metabolites.

scholarly journals Glycyrrhizin improves the pathogenesis of psoriasis partially through IL-17A and the SIRT1-STAT3 axis

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Huang Qiong ◽  
Ling Han ◽  
Nanxue Zhang ◽  
Huyan Chen ◽  
Kexiang Yan ◽  
...  
Keyword(s):  
Cell Counting ◽  
Enzyme Linked Immunosorbent Assay ◽  
Pathological State ◽  
Hacat Cells ◽  
Skin Cells ◽  
Tnf Α ◽  
Ifn Γ ◽  
Interfering Rna

Abstract Background The anti-inflammatory effect of glycyrrhizin has been widely recognized, while the specific mechanism of glycyrrhizin in psoriasis remains poorly understood. Results In the imiquimod-induced mouse model of psoriasis (IMD), we found that glycyrrhizin can substantially improve the adverse symptoms in mice. The hematoxylin-eosin staining results showed that glycyrrhizin can also improve the pathological state of skin cells in IMD mice. Using enzyme-linked immunosorbent assay (ELISA), we found that glycyrrhizin substantially inhibited the expression of IL-17A and IFN-γ in the serum of IMD mice. In order to simulate the effect of IL-17A on keratinocytes in psoriasis, we treated HaCaT cells with 100 ng/mL IL-17A (IL-17A-HaCaT cells) for 48 h. Then, using cell-counting kit-8 (CCK-8) and ELISA assays, we found that glycyrrhizin inhibited the proliferation of IL-17A-HaCaT cells and reversed the promotion of IL-6, CCL20, and TNF-α induced by IL-17A. Further, western blotting (WB) results indicated that glycyrrhizin promoted the expression of SIRT1 and inhibited the expression of STAT3 and phosphorylated STAT3 (p-STAT3). By treating IL-17A-HaCaT cells with EX-527 (a potent and selective inhibitor of SIRT1), combined with CCK-8 and WB experiments, we initially found that EX-527 inhibited the proliferation of IL-17A-HaCaT cells and promoted the expression of STAT3, p-STAT3, and acetylated STAT3 (a-STAT3). However, when glycyrrhizin was added at the same time, the proliferation of IL-17A-HaCaT cells increased, and the expression of STAT3, p-STAT3, and a-STAT3 reduced. We then knocked down the expression of SIRT1 via small interfering RNA in IL-17A-HaCaT cells, and the results were consistent with those of EX-527. Conclusions Together, these results indicated that glycyrrhizin improved psoriasis by inhibiting the expression of IL-17A and IFN-γ in vivo and suppressed the proliferation of IL-17A-HaCaT cells and the expression of STAT3, p-STAT3, and a-STAT3 by upregulating SIRT1 in vitro.

scholarly journals Glycyrrhizin improves the pathogenesis of psoriasis through IL-17A and the SIRT1-STAT3 axis

2020 ◽  
Author(s):  
Huang Qiong ◽  
Ling Han ◽  
Nan Zhang ◽  
Hu Chen ◽  
Ke Yan ◽  
...  
Keyword(s):  
Cell Counting ◽  
Enzyme Linked Immunosorbent Assay ◽  
Pathological State ◽  
Hacat Cells ◽  
Skin Cells ◽  
Tnf Α ◽  
Ifn Γ ◽  
Interfering Rna

Abstract Background: The anti-inflammatory effect of glycyrrhizin has been widely recognized, while the specific mechanism of glycyrrhizin in psoriasis remains poorly understood. Results: Here, in an imiquimd-induced mouse model of psoriasis (IMD), we found that glycyrrhizin can substantially improve the adverse symptoms in mice. The hematoxylin-eosin staining results showed that glycyrrhizin can also improve the pathological state of skin cells in IMD mice. Using enzyme-linked immunosorbent assay (ELISA), we found that glycyrrhizin substantially inhibited the expression of IL-17A and IFN-γ in the serum of IMD mice. In order to simulate the effect of IL-17A on keratinocytes in psoriasis, we treated HaCaT cells with 100 ng/mL IL-17A (IL-17A-HaCaT cells) for 48 h. Then, using cell-counting kit-8 (CCK-8) and ELISA assays, we found that glycyrrhizin inhibited the proliferation of IL-17A-HaCaT cells and reversed the promotion of IL-6, CCL20, and TNF-α induced by IL-17A. Further, western blotting (WB) results indicated that glycyrrhizin promoted the expression of SIRT1 and inhibited the expression of STAT3 and phosphorylated STAT3 (p-STAT3). By treating IL-17A-HaCaT cells with EX-527 (a potent and selective inhibitor of SIRT1), combined with CCK-8 and WB experiments, we initially found that EX-527 inhibited the proliferation of IL-17A-HaCaT cells and promoted the expression of STAT3, p-STAT3, and acetylated STAT3 (a-STAT3). However, when glycyrrhizin was added at the same time, the proliferation of IL-17A-HaCaT cells increased, and the expression of STAT3, p-STAT3, and a-STAT3 reduced. We then knocked down the expression of SIRT1 via small interfering RNA in IL-17A-HaCaT cells, and the results were consistent with those of EX-527. Conclusions: Together, these results indicated that glycyrrhizin improved psoriasis by inhibiting the expression of IL-17A and IFN-γ in vivo and suppressed the proliferation of IL-17A-HaCaT cells and the expression of STAT3, p-STAT3, and a-STAT3 by upregulating SIRT1 in vitro.

scholarly journals Astragaloside IV exerts anti-inflammatory role in endometriosis by downregulating TLR4/NF-κB pathway

2021 ◽  
Vol 18 (3) ◽  
pp. 539-545
Author(s):  
Yongping Zhang ◽  
Ouping Huang ◽  
Wei Zhang ◽  
Luxin Liu ◽  
Caiwei Xu
Keyword(s):  
Inflammatory Cytokines ◽  
Underlying Mechanism ◽  
Nuclear Factor Κb ◽  
Enzyme Linked Immunosorbent Assay ◽  
Astragaloside Iv ◽  
Tnf Α ◽  
Hematoxylin And Eosin ◽  
And Control ◽  
Novel Drug

Purpose: To investigate the effect of astragaloside IV administration on the inflammatory response in endometriosis and the underlying mechanism of action. Methods: Mice were divided into two groups: endometriosis (EMs) mice and control mice (n = 12). EMs induction in mice was achieved by transplantation of mouse uterine tissue. The same procedure was performed in control mice except that a separate suture was inserted instead of endometrial tissue. After 5 weeks, EMs mice were treated with or without astragaloside IV (AIV). The tissue lesions in EMs and control mice were stained with hematoxylin and eosin staining. The activation of toll-like receptor 4 (TLR4) and nuclear factor-κB (NF-κB) p65 signaling was evaluated by western blot, while expression of inflammatory cytokines was evaluated by quantitative real-time-polymerase chain reaction (qRT-PCR), and enzyme-linked immunosorbent assay (ELISA). Results: Astragaloside IV repressed the inflammation of murine Ems lesions, and also dampened the activation of TLR4/NF-κB signaling in vivo and vitro (p < 0.01 and p < 0.001, respectively). In addition, the expression levels of inflammatory cytokines (IL-1β, IL-6, Ccl-2, and TNF-α) decreased following AIV treatment in vivo. Conclusion: The results indicate that TLR4/NF-κB signaling pathways are closely related to the inhibition of Ems inflammation by astragaloside IV. Thus, astragaloside IV may be a novel drug for the prevention and treatment of endometrioses.

scholarly journals Advanced glycation end product levels were correlated with inflammation and carotid atherosclerosis in type 2 diabetes patients

2020 ◽  
Vol 15 (1) ◽  
pp. 364-372 ◽  
Author(s):  
Jie Li ◽  
Haiyan Shangguan ◽  
Xiaoqian Chen ◽  
Xiao Ye ◽  
Bin Zhong ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Type 2 Diabetes ◽  
Color Doppler ◽  
Enzyme Linked Immunosorbent Assay ◽  
Advanced Glycation ◽  
Advanced Glycation End Product ◽  
Inflammatory Status ◽  
Tnf Α ◽  
Ifn Γ

AbstractDiabetes mellitus with atherosclerosis (AS) adds to the social burden. This study aimed to investigate whether advanced glycation end product (AGE) levels were correlated with inflammation and carotid AS (CAS) in type 2 diabetes mellitus (T2DM) patients. A total of 50 elderly T2DM patients and 50 age-matched senior healthy subjects were recruited in this study. T2DM patients were classified into two groups based on the intima–media thickness (IMT) of the carotid artery from color Doppler ultrasonography. Patients with IMT > 1 mm were classified into the T2DM + CAS group (n = 28), and patients with IMT < 1 mm were assigned as the T2DM + non-atherosclerosis (NAS) group (n = 22). The plasma levels of AGEs, receptor for AGE (RAGE), tumor necrosis factor alpha (TNF-α), and interferon gamma (IFN-γ) of all subjects were measured by enzyme-linked immunosorbent assay. The T-lymphocyte subsets were analyzed by a flow detector. T2DM + CAS patients showed significantly higher concentrations of AGEs, RAGE, TNF-α, and IFN-γ in the peripheral blood. The highest levels of CD4+ T cells were observed in the T2DM + CAS group. The AGE level was positively correlated with the concentrations of RAGE, TNF-α, IFN-γ, and CD4+. In summary, the results showed that the levels of AGEs may be correlated with the inflammatory status in T2DM patients with CAS.

scholarly journals Pirfenidone attenuates synovial fibrosis and postpones the progression of osteoarthritis by anti-fibrotic and anti-inflammatory properties in vivo and in vitro

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Qilu Wei ◽  
Ning Kong ◽  
Xiaohui Liu ◽  
Run Tian ◽  
Ming Jiao ◽  
...  
Keyword(s):  
Protein Expression ◽  
Cell Counting ◽  
Enzyme Linked Immunosorbent Assay ◽  
Fast Green ◽  
Expression Levels ◽  
Tnf Α ◽  
Anti Inflammatory ◽  
Safranin O ◽  
Tgf Β1

Abstract Background Osteoarthritis (OA) is a disease of the entire joint involving synovial fibrosis and inflammation. Pathological changes to the synovium can accelerate the progression of OA. Pirfenidone (PFD) is a potent anti-fibrotic drug with additional anti-inflammatory properties. However, the influence of PFD on OA is unknown. Methods Proliferation of human fibroblast-like synoviocytes (FLSs) after treatment with TGF-β1 or PFD was evaluated using a Cell Counting Kit-8 assay and their migration using a Transwell assay. The expression of fibrosis-related genes (COL1A1, TIMP-1, and ACTA-2) and those related to inflammation (IL-6 and TNF-α) was quantified by real-time quantitative PCR. The protein expression levels of COL1A1, α-SMA (coded by ACTA-2), IL-6 and TNF-α were measured by enzyme-linked immunosorbent assay. A rabbit model of OA was established and then PFD was administered by gavage. The expression of genes related to fibrosis (COL1A1, TIMP-1, and ADAM-12) and inflammation (IL-6 and TNF-α) was measured using RNA extracted from the synovium. Synovial tissue was examined histologically after staining with H&E, Masson’s trichrome, and immunofluorescence. Synovitis scores, the volume fraction of collagen, and mean fluorescence intensity were calculated. Degeneration of articular cartilage was analyzed using a Safranin O-fast green stain and OARSI grading. Results The proliferation of FLSs was greatest when induced with 2.5 ng/ml TGF-β1 although it did not promote their migration. Therefore, 2.5 ng/ml TGF-β1 was used to stimulate the FLSs and evaluate the effects of PFD, which inhibited the migration of FLSs at concentrations as low as 1.0 mg/ml. PFD decreased the expression of COL1A1 while TGF-β1 increased both mRNA and protein expression levels of IL-6 but had no effect on α-SMA or TNF-α expression. PFD decreased mRNA expression levels of COL1A1, IL-6, and TNF-α in vivo. H&E staining and synovitis scores indicated that PFD reduced synovial inflammation, while Masson’s trichrome and immunofluorescence staining suggested that PFD decreased synovial fibrosis. Safranin O-Fast Green staining and the OARSI scores demonstrated that PFD delayed the progression of OA. Conclusions PFD attenuated synovial fibrosis and inflammation, and postponed the progression of osteoarthritis in a modified Hulth model of OA in rabbits, which was related to its anti-fibrotic and anti-inflammatory properties.

scholarly journals Inflammatory cytokines-stimulated human muscle stem cells ameliorate ulcerative colitis via the IDO-TSG6 axis

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Shengchao Zhang ◽  
Jiankai Fang ◽  
Zhanhong Liu ◽  
Pengbo Hou ◽  
Lijuan Cao ◽  
...  
Keyword(s):  
Ulcerative Colitis ◽  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Inflammatory Cytokines ◽  
Human Muscle ◽  
Enzyme Linked Immunosorbent Assay ◽  
Muscle Stem Cells ◽  
Tnf Α ◽  
Ifn Γ ◽  
Anti Inflammatory

Abstract Background Muscle stem cells (MuSCs) are absolutely required for the formation, repair, and regeneration of skeletal muscle tissue. Increasing evidence demonstrated that tissue stem cells, especially mesenchymal stem cells (MSCs), can exert therapeutic effects on various degenerative and inflammatory disorders based on their immunoregulatory properties. Human mesenchymal stem cells (hMSCs) treated with interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) were reported to possess anti-inflammatory functions by producing TNF-stimulated gene 6 (TSG-6). However, whether human muscle stem cells (hMuSCs) also possess TSG-6 mediated anti-inflammatory functions has not been explored. Methods The ulcerative colitis mouse model was established by subjecting mice to dextran sulfate sodium (DSS) in drinking water for 7 days. hMuSCs were pretreated with IFN-γ and TNF-α for 48 h and were then transplanted intravenously at day 2 of DSS administration. Body weights were monitored daily. Indoleamine 2,3-dioxygenase (IDO) and TSG-6 in hMuSCs were knocked down with short hairpin RNA (shRNA) and small interfering RNA (siRNA), respectively. Colon tissues were collected for length measurement and histopathological examination. The serum level of IL-6 in mice was measured by enzyme-linked immunosorbent assay (ELISA). Real-time PCR and Western blot analysis were performed to evaluate gene expression. Results hMuSCs treated with inflammatory factors significantly ameliorated inflammatory bowel disease (IBD) symptoms. IDO and TSG-6 were greatly upregulated and required for the beneficial effects of hMuSCs on IBD. Mechanistically, the tryptophan metabolites, kynurenine (KYN) or kynurenic acid (KYNA) produced by IDO, augmented the expression of TSG-6 through activating their common receptor aryl hydrocarbon receptor (AHR). Conclusion Inflammatory cytokines-treated hMuSCs can alleviate DSS-induced colitis through IDO-mediated TSG-6 production.

scholarly journals Upregulation of Cytokines Is Detected in the Placentas of Cattle Infected with Neospora caninum and Is More Marked Early in Gestation When Fetal Death Is Observed

2008 ◽  
Vol 76 (6) ◽  
pp. 2352-2361 ◽  
Author(s):  
Anne Rosbottom ◽  
E. Helen Gibney ◽  
Catherine S. Guy ◽  
Anja Kipar ◽  
Robert F. Smith ◽  
...  
Keyword(s):  
Protein Expression ◽  
Fetal Death ◽  
Neospora Caninum ◽  
Late Gestation ◽  
Enzyme Linked Immunosorbent Assay ◽  
Mrna Levels ◽  
Cytokine Mrna ◽  
Early Gestation ◽  
Tnf Α ◽  
Ifn Γ

ABSTRACT The protozoan parasite Neospora caninum causes fetal death after experimental infection of pregnant cattle in early gestation, but the fetus survives a similar infection in late gestation. An increase in Th1-type cytokines in the placenta in response to the presence of the parasite has been implicated as a contributory factor to fetal death due to immune-mediated pathological alterations. We measured, using real-time reverse transcription-PCR and enzyme-linked immunosorbent assay, the levels of cytokines in the placentas of cattle experimentally infected with N. caninum in early and late gestation. After infection in early gestation, fetal death occurred, and the levels of mRNA of both Th1 and Th2 cytokines, including interleukin-2 (IL-2), gamma interferon (IFN-γ), IL-12p40, tumor necrosis factor alpha (TNF-α), IL-18, IL-10, and IL-4, were significantly (P < 0.01) increased by up to 1,000-fold. There was extensive placental necrosis and a corresponding infiltration of CD4+ T cells and macrophages. IFN-γ protein expression was also highly increased, and a modest increase in transforming growth factor β was detected. A much smaller increase in the same cytokines and IFN-γ protein expression, with minimal placental necrosis and inflammatory infiltration, occurred after N. caninum infection in late gestation when the fetuses survived. Comparison of cytokine mRNA levels in separated maternal and fetal placental tissue that showed maternal tissue was the major source of all cytokine mRNA except for IL-10 and TNF-α, which were similar in both maternal and fetal tissues. These results suggest that the magnitude of the cytokine response correlates with but is not necessarily the cause of fetal death and demonstrate that a polarized Th1 response was not evident in the placentas of N. caninum-infected cattle.

Clinical significance of cytokine markers in children with different courses of community-acquired pneumonia

2020 ◽  
Vol 15 (5) ◽  
pp. 18-23
Author(s):  
G.P. Evseeva ◽  
◽  
G.N. Kholodok ◽  
S.V. Pichugina ◽  
S.V. Suprun ◽  
...  
Keyword(s):  
Cytokine Production ◽  
Interleukin 1 ◽  
Interferon Γ ◽  
Peripheral Blood Lymphocytes ◽  
Community Acquired Pneumonia ◽  
Enzyme Linked Immunosorbent Assay ◽  
Interleukin 17 ◽  
Monocyte Chemoattractant Protein 1 ◽  
Tnf Α ◽  
Ifn Γ

Principles of the diagnosis and treatment of community-acquired pneumonia (CAP) in children were developed and clearly formulated long ago. Nevertheless, clinicians often encounter the problem of pulmonary and pleural complications of CAP, which is challenging in terms of the choice of initial therapy, since the first symptoms of uncomplicated and complicated pneumonia are often similar. Therefore, the search for early markers of complicated CAP in children is highly important. Objective. To assess prognostic values of spontaneous and mitogen-induced cytokine production in children with CAP. Patients and methods. We have performed comprehensive examination of 108 children with CAP. Eighty-four of them had uncomplicated CAP, whereas 24 children had CAP complicated by pleurisy. We measured spontaneous and induced production of the following cytokines upon patient admission to hospital: interleukin-1 (IL-1), interleukin-17 (IL-17), interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), vascular endothelial growth factor (VEGF), and monocyte chemoattractant protein-1 (MCP-1). To measure induced cytokine production, we stimulated peripheral blood lymphocytes by S. рneumonае (serotype 7, 11; strains 7C and 11AD). The level of cytokines was evaluated using the enzyme-linked immunosorbent assay (Vektor-BEST, Novosibirsk, Russia). Results. We found that in children with uncomplicated CAP, induction of immunocompetent blood cells (IBCs) led to increased secretion of first-generation cytokines, including IL-1, TNF-α, and IFN-γ, whereas IBCs of patients with complicated CAP primarily produced second-generation cytokines, including VEGF, МРС-1, and IL-17. Conclusion. The observed differences in spontaneous and mitogen-induced cytokine production between children with and without CAP complications suggest that these parameters can be considered as promising prognostic markers for complicated CAP in children. The proposed method can be used in pediatric practice to predict the development of complications in children with CAP. Key words: children, community-acquired pneumonia, cytokines

Προβιοτικές και τεχνολογικές ιδιότητες οξυγαλακτικών βακτηρίων. In vitro και in vivo επίδραση στο ελικοβακτήριο του πυλωρού

2004 ◽  
Author(s):  
Πέτρος-Αχιλλέας Μαραγκουδάκης
Keyword(s):  
E Coli ◽  
Tnf Α ◽  
Ifn Γ

Σκοπός: Ο σκοπός της παρούσας διατριβής ήταν η εξέταση του προβιοτικού δυναμικού στελεχών οξυγαλακτικών βακτηρίων μέσω μίας σειράς in vitro δοκιμών, και της μετέπειτα εφαρμογής επιλεγμένων στελεχών σε in vivo μοντέλα ποντικών έναντι της λοίμωξης του Η. pylori και της ελκώδους κολίτιδας, αλλά και σε τεχνολογικό επίπεδο στην παρασκευή γιαουρτιού.Υλικά και μέθοδοι: Στη διατριβή αυτή μελετήθηκαν 51 στελέχη Lactobacillus του Εργαστηρίου Γαλακτοκομίας του Γεωπονικού Πανεπιστημίου Αθηνών, απομονωμένα κυρίως από γαλακτοκομικά προϊόντα και κόπρανα προβάτων, καθώς και 22 στελέχη Enterococcus και Streptococcus, απομονωμένα από κόπρανα προβάτων. Τα στελέχη αυτά εξετάστηκαν σε μία σειρά in vitro δοκιμών που αφορούν την επιβίωσή τους σε συνθήκες εξομοίωσης του ανθρώπινου γαστρεντερικού συστήματος, οι οποίες περιελάμβαναν επιβίωση σε χαμηλό pH, επιβίωση παρουσία των πρωτεολυτικών ενζύμων πεψίνη και παγκρεατίνη, και επιβίωση παρουσία χολικών αλάτων.Στην συνέχεια τα στελέχη εξετάστηκαν σε δοκιμές βασικές για την ασφάλεια χρήσης τους στον ανθρώπινο οργανισμό. "Ολα τα στελέχη δοκιμάστηκαν ως προς την αιμολυτική τους δραστικότητα, και τα στελέχη γαλακτοβακίλλων συγκεκριμένα για την ανθεκτικότητά τους έναντι επιλεγμένων αντιβιοτικών.Παράλληλα, εξετάστηκαν in vitro βασικές ιδιότητες που θεωρούνται επιθυμητές για τα προβιοτικά στελέχη, όπως υδρόλυση των χολικών αλάτων, μελέτη της υδροφοβίας και της ικανότητας πρόσδεσης των γαλακτοβακίλλων σε κύτταρα Caco-2, ικανότητά διέγερσης κυττάρων του ανθρώπινου οργανισμού (PBMCs), καθώς και μελέτη της αντιμικροβιακής δράσης έναντι παθογόνων βακτηρίων και της δυνατότητάς αναστολής της πρόσδεσης παθογόνων σε κύτταρα Caco-2.Στην συνέχεια πραγματοποιήθηκαν in vivo μελέτες σε ποντίκια, για την εξακρίβωση του προβιοτικού χαρακτήρα επιλεγμένων στελεχών. Τα στελέχη L. casei Shirota ACA-DC 6002 και L. paracasei subsp. tolerans ACA-DC 4037 χορηγήθηκαν σε ποντίκια επιμολυσμένα με Η. pylori και αξιολογήθηκε η επίδραση των γαλακτοβακίλλων αυτών στον αποικισμό του παθογόνου και στην αξιολόγηση του βαθμού και της δραστικότητας στο στομάχι. Επίσης, τα στελέχη αυτά χρησιμοποιήθηκαν και για την πρόληψη TNBS- κολίτιδας σε ποντίκια.Τέλος, επιλεγμένα στελέχη γαλακτοβακίλλων αξιολογήθηκαν για την τεχνολογική τους εφαρμογή, μελετώντας την ικανότητά οξίνϊσης του γάλακτος και τη χρήση τους ως καλλιέργειες για την παρασκευή γιαούρτηςΑποτελέσματα: Ορισμένα στελέχη βρέθηκαν να έχουν ικανοποιητική επιβίωση σε συνθήκες εξομοίωσης του ανθρώπινου πεπτικού συστήματος. Κανένα στέλεχος δεν βρέθηκε να έχει ισχυρή (β-) αιμολυτική δράση, ενώ η αντοχή των γαλακτοβακίλλων έναντι επιλεγμένων αντιβιοτικών δεν παρουσιάστηκε διαφορετική από την έμφυτη και αναμενόμενη, ανάλογα το είδος των εξεταζόμενων γαλακτοβακίλλων, ενώ αρκετά στελέχη παρουσίασαν ικανότητα υδρόλυσης χολικών αλάτων. Τα στελέχη παρουσίασαν ποικιλόμορφη πρόσδεση στους οργανικούς διαλύτες, αλλά γενικά τα περισσότερα στελέχη δεν παρουσίασαν μεγάλη υδροφοβία, ενώ αρκετά στελέχη γαλακτοβακίλλων παρουσίασαν ικανοποιητική πρόσδεση σε κύτταρα Caco-2 (>5%), με το στέλεχος L. plantarum ACA-DC 146 (25% πρόσδεση) να ξεχωρίζει. Το ίδιο στέλεχος, μαζί με το L. paracasei subsp. tolerans ACA-DC 4037 βρέθηκαν να προκαλούν την έκκριση υψηλών επιπέδων φλεγμονωδών κυτταροκινών (IL-12, TNF-α και IFN-γ) από PBMCs, ενώ αντίθετα το στέλεχος L. casei Shirota ACA-DC 6002 προκάλεσε την έκκριση της αντιφλεγμονώδους κυτταροκίνης IL-10. Παρόλο που κανένα από τα υπερκείμενα των στελεχών δεν παρεμπόδισε τα στελέχη E. coli, S. typhimurium και Η. pylori, ορισμένα στελέχη, όπως τα L. casei Shirota, L. plantarum ACA-DC 146 και L. paracasei subsp. tolerans ACA-DC 4037 προκάλεσαν την αναστολή της πρόσδεσης εντερικών παθογόνων (E. coli και S. typhimurium) σε κύτταρα Caco-2 σε επίπεδα μέχρι και 50%.In vivo, η χορήγηση του L. casei Shirota ACA-DC 6002 σε ποντίκια οδήγησε στην μείωση του βαθμού και της δραστικότητας της γαστρίτιδας αλλά και στον αποικισμό του Η. pylori. Παρόμοια αποτελέσματα, αλλά σε μικρότερη έκταση, παρατηρήθηκαν με την χορήγηση του στελέχους L. paracasei subsp. tolerans ACA-DC 4037. Παράλληλα, το στέλεχος L. casei Shirota ACA-DC 6002 δείχνει να παρέχει προστασία σε ποντίκια κατά την πρόκληση ελκώδους κολίτιδας με την χορήγηση TNBS.Σε τεχνολογικό επίπεδο, κανένα από τα εξεταζόμενα στελέχη δεν παρουσίασε υψηλή ικανότητα οξύνισης στο γάλα και κατά συνέπεια δεν ήταν δυνατόν να χρησιμοποιηθούν ως εναρκτήριες καλλιέργειες για την παρασκευή γιαούρτης. Από την άλλη, καθώς κανένα στέλεχος δεν παρεμποδίζει αλλά και δεν παρεμποδίζεται από τις παραδοσιακές εναρκτήριες καλλιέργειες γιαούρτης, ήταν δυνατή η χρήση τους ως συμπληρωματικές καλλιέργειας για την παρασκευή γιαούρτης. Στην συνέχεια επιλεγμένα στελέχη χρησιμοποιήθηκαν για το σκοπό αυτό και το στέλεχος L. paracasei subsp. tolerans ACA- DC 4037 ξεχώρισε όταν χρησιμοποιήθηκε ως συμπληρωματική καλλιέργεια για την παρασκευή γιαούρτης με εμβόλιο πηγμένου γάλακτος (1% ν/ν) στους 42°C, λόγω της υψηλής μικροβιακής, φυσικοχημικής και οργανοληπτικής ποιότητας του προϊόντος. Συμπεράσματα: Τα στελέχη L. casei Shirota ACA-DC 6002, L. plantarum ACA-DC 146 και L. paracasei subsp. tolerans ACA-DC 4037, επέδειξαν υποσχόμενο προβιοτικό δυναμικό κατά την διάρκεια εκτεταμένων in vitro και in vivo δοκιμών. Η μελέτη αυτή επιβεβαιώνει τις προβιοτικές ιδιότητες του L. casei Shirota και επιδεικνύει την πιθανή εφαρμογής του στη λοίμωξη του Η. pylori και στην ελκώδη κολίτιδα στον άνθρωπο. Επιπλέον, το στέλεχος L paracasei subsp. tolerans ACA-DC 4037 διαθέτει επίσης δυναμικό χρήσης έναντι του Η. pylori αλλά και στην παρασκευή ενός επιτυχημένου προβιοτικού γιαουρτιού. Τέλος, το στέλεχος L. plantarum ACA-DC 146 μπορεί να εξεταστεί in vivo σε μοντέλα αλλεργικών αντιδράσεων, λόγω της υψηλής αντιφλεγμονώδους επίδρασής τους σε ανθρώπινα περιφερειακά μονοπύρηνα (PBMCs.)

Sign in / Sign up

Export Citation Format

Share Document