Modulation of Matrix Metalloproteinase and Cytokine Production by Licorice Isolates Licoricidin and Licorisoflavan A: Potential Therapeutic Approach for Periodontitis

Background: Inflammatory cytokines and matrix metalloproteinases (MMPs) produced by resident and inflammatory cells in response to periodontopathogens play a major role in the tissue destruction observed in periodontitis, which is a disease that affects tooth‐supporting structures. In the present study, we investigate the effects of licorice‐derived licoricidin (LC) and licorisoflavan A (LIA) on the secretion of various cytokines and MMPs by human monocyte‐derived macrophages stimulated with Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans) lipopolysaccharide (LPS). Methods: Macrophages were treated with non‐toxic concentrations of LC or LIA before being stimulated with A. actinomycetemcomitans LPS. The secretion of cytokines and MMPs and the activation of nuclear factor‐kappa B (NF‐κB) p65 and activator protein (AP)‐1 were assessed by enzyme‐linked immunosorbent assays. Results: LC and LIA inhibited the secretion of interleukin (IL)‐6 and chemokine (C‐C motif) ligand 5 in a concentration‐dependent manner but did not affect the secretion of IL‐8 by LPS‐stimulated macrophages. LC and LIA also inhibited the secretion of MMP‐7, ‐8, and ‐9 by macrophages. The suppression of cytokine and MMP secretion by LC and LIA was associated with the reduced activation of NF‐κB p65 but not that of AP‐1. Conclusion: The present study suggests that LC and LIA have potential for the development of novel host‐modulating strategies for the treatment of cytokine and/or MMP‐mediated disorders such as periodontitis.     

SOCS1 and SOCS3 are the main negative modulators of the somatotrophic axis in liver of homozygous GH-transgenic zebrafish (Danio rerio)

Homozygote individuals (HO) of the GH-transgenic zebrafish lineage (F0104), despite expressing double the amount of growth hormone (GH) in relation to the hemizygote (HE) individuals, presented smaller growth in relation to the last, and similar to the non-transgenic (NT) group. Through the analysis of the expression of genes of the somatotrophic axis in the livers of HO and NT individuals, it was verified that GHR, JAK2 and STAT5.1 did not present significant differences among the analyzed genotypes (NT and HO). However, in the IGF-I gene expression, an accentuated decrease was observed in group HO (p < 0.01), suggesting a resistance effect to excess GH. This resistance could be related to the insufficient amount of energy for supporting the accelerated metabolic demand caused by excess circulating GH. Analysis of the genes involved in the regulation of GH signalization by dephosphorylation (PTP-H1 and PTP-1B) did not show any significant alteration when comparing groups HO and NT. However, the analysis of the SOCS1 and SOCS3 genes showed an induction in homozygotes of 2.5 times (p < 0.01) and 4.3 times (p < 0.05), respectively, in relation to non-transgenics. The results of the present work demonstrate that, in homozygotes, GH signaling is reduced by the action of the SOCS1 and SOCS3 proteins.     

Distinct roles for interleukin-12p40 and tumour necrosis factor in resistance to oral candidiasis defined by gene-targeting

Cell-mediated immunity is important for anti-Candida host defence in mucosal tissues. In this study we used cytokine-specific gene knockout mice to investigate the requirement for T helper type 1 (Th1) and Th2 cytokines in recovery from oral candidiasis. Knockout mice used in this study included interleukin-4 (IL-4), IL-10, IL-12p40, interferon-gamma (IFN-gamma), and tumour necrosis factor (TNF). The mice were challenged either orally or systemically with Candida albicans yeasts, and levels of colonization were determined. IL-12p40 knockout mice developed chronic oropharyngeal candidiasis, but were not more susceptible to systemic challenge. On the other hand, TNF knockout mice displayed increased susceptibility to both oral and systemic challenge, but only in the acute stages of infection. TNF apparently has a protective effect in the acute stages of both oral and systemic candidiasis, whereas IL-12p40 is essential for recovery from oral but not systemic candidiasis. The role of IL-12p40, and its relation to T-cell-mediated responses remain to be determined.     

Association of interleukin-1beta polymorphism with recurrent aphthous stomatitis in Brazilian individuals

BACKGROUND: Recurrent aphthous stomatitis (RAS) is characterized by recurrent episodes of oral ulceration in an otherwise healthy individual. Some reports in the literature indicate that RAS may have immunological, psychological, genetic and microbiological bases. The purpose of the present study was to investigate the possible association between interleukin-1beta (IL-1beta) +3954 (C/T) genetic polymorphism and RAS in a sample of Brazilian patients. SUBJECTS AND METHODS: Sixty-two consecutive subjects affected by minor and major forms of RAS and 62 healthy volunteers were genotyped at IL-1beta (+3954). The chi-squared test was used for statistical analysis. RESULTS: A significant increase in the high production of IL-1beta genotype CT was observed in the group with RAS (P = 0.01). After stratifying RAS patients according to the mean number of lesions per episode, a significant difference was only observed between patients with >or=3 lesions in each episode and control. CONCLUSION: There is an increased frequency of polymorphism associated with high IL-1beta production in RAS patients.     

Probiotics modulate inflammatory cytokine secretion from inflamed mucosa in active ulcerative colitis

Enteric microflora of ulcerative colitis patients becomes aberrant. The abnormal interaction between microflora and intestinal mucosal immune system leads the mucosal inflammation. Probiotic administration may recover the commensal microflora and normalise the host-microbial interaction. In this experiment, we cocultured colonic biopsies from active ulcerative colitis patients with bifidobacterium to investigate the modulation effect of probiotics on inflamed colonic tissues and its possible mechanism. Colonic biopsies from active ulcerative colitis were cocultured for 24 h with Bifidobacterium longum. Tumour necrosis factor (TNF)-alpha and interleukin (IL)-8 in supernatants were measured using enzyme-linked immunosorbent assays, the biopsies were fixed using paraffin and the expression of NF-kappaB P65 of tissues was studied using immunohistochemical staining. The concentrations of TNF-alpha and IL-8 in supernatants of tissues cocultured with probiotics were lower than those cultured alone. The number of lamina propria mononuclear cells (LPMC) with nuclear factor-kappa B (NF-kappaB) P65 positive in cocultured tissues was also decreased. When cocultured with inflamed tissues of active ulcerative colitis, probiotics could inhibit NF-kappaB activation in LPMC and down-regulate inflammatory cytokine secretion from inflamed tissues of active ulcerative colitis.     

Emotion with tears decreases allergic responses to latex in atopic eczema patients with latex allergy

OBJECTIVE: Allergic responses are enhanced by stress, whereas they are reduced by laughter in atopic eczema patients. Emotion with tears decreases plasma IL-6 levels in patients with rheumatoid arthritis. Thus, the effect of emotion with tears on allergic responses in patients with atopic eczema was studied. METHODS: Sixty patients with atopic eczema having latex allergy viewed both the weather information video and the heart-warming movie, Kramer vs. Kramer. Just before and immediately after viewing each video, allergic responses to latex were measured. RESULTS: Viewing the weather information video did not cause emotion with tears in any patients, and it failed to modulate allergic responses. In contrast, viewing Kramer vs. Kramer caused emotion with tears in 44 of 60 patients, and it reduced allergic skin wheal responses to latex and latex-specific IgE production in them. CONCLUSION: Emotion with tears reduced allergic responses, and it may be useful in the treatment of allergic diseases.