mRNA Expression Of Antimicrobial Peptides Research Articles

Fluoride exposure cause colon microbiota dysbiosis by destroyed microenvironment and disturbed antimicrobial peptides expression in colon

Colon microenvironment and microbiota dysbiosis are closely related to various human metabolic diseases. In this study, a total of 72 healthy female mice were exposed to fluoride (F) (0, 25, 50 and 100 mg/L F−) in drinking water for 70 days. The effect of F on intestinal barrier and the diversity and composition in colon microbiota have been evaluated. Meanwhile, the relationship among F-induced colon microbiota alterations and antimicrobial peptides (AMPs) expression and short-chain fatty acids (SCFAs) level also been assessed. The results suggested that F decreased the goblet cells number and glycoprotein expression in colon. And further high-throughput 16S rRNA gene sequencing result demonstrated that F exposure induced the diversity and community composition of colonic microbiota significantly changes. Linear Discriminant Analysis Effect Size (LEfSe) analysis identified 11 predominantly characteristic taxa which may be the biomarker in response to F exposure. F-induced intestinal microbiota perturbations lead to the significantly decreased SCFAs levels in colon. Immunofluorescence results showed that F increased the protein expression of interleukin-17A (IL-17A) and IL-22 (P < 0.01) and disturbed the expression of interleukin-17 receptor A (IL-17RA) and IL-22R (P < 0.05 or P < 0.01). In addition, the increased expression of IL-17A and IL-22 cooperatively enhanced the mRNA expression of AMPs which response to F-induced microbiota perturbations. Collectively, destroyed microenvironment and disturbed AMPs are the primary reason of microbiota dysbiosis in colon after F exposure. Colonic homoeostasis imbalance would be helpful for finding the source of F-induced chronic systemic diseases.

Expression of Antimicrobial Peptides and Cytokines in Human Omentum Following Abdominal Surgery.

IntroductionOmentum can secrete out biological agents like different growth factors, cytokines, and antimicrobial peptides. The aim of our study was to determine the expression of antimicrobial peptides and cytokines in human omentum tissue and its response to intra-abdominal infection.MethodologyOmentum tissue was obtained from 60 patients: control (n=20) and cases (n=40). mRNA expression of antimicrobial peptides (LL-37, HBD-1, HBD-2, HNP1-3) and cytokines (TNF- α, IL-8, IL-10, IL1β) was evaluated using Real-Time PCR. Protein quantification was done by Immunoblotting and ELISA.ResultsSignificantly higher expression of antimicrobial peptides (LL-37, HBD-1, HBD-2, HNP1-3) and cytokines (TNF- α, IL-8, IL-10, IL1β) was observed in cases as compared to control at both the transcriptional and translational level (p<0.0001).ConclusionOmentum governs a population of antimicrobial peptides with potent immunologic functions. The expression of antimicrobial peptides and cytokines is inducible and increases with the severity of infection. Omentum is thus an immunologically active and adaptable organ but its complete regulatory mechanism is still elusive.

Honey Bee Suppresses the Parasitic Mite Vitellogenin by Antimicrobial Peptide.

The negative effects of honey bee parasitic mites and deformed wing virus (DWV) on honey bee and colony health have been well characterized. However, the relationship between DWV and mites, particularly viral replication inside the mites, remains unclear. Furthermore, the physiological outcomes of honey bee immune responses stimulated by DWV and the mite to the host (honey bee) and perhaps the pathogen/parasite (DWV/mite) are not yet understood. To answer these questions, we studied the tripartite interactions between the honey bee, Tropilaelaps mercedesae, and DWV as the model. T. mercedesae functioned as a vector for DWV without supporting active viral replication. Thus, DWV negligibly affected mite fitness. Mite infestation induced mRNA expression of antimicrobial peptides (AMPs), Defensin-1 and Hymenoptaecin, which correlated with DWV copy number in honey bee pupae and mite feeding, respectively. Feeding T. mercedesae with fruit fly S2 cells heterologously expressing honey bee Hymenoptaecin significantly downregulated mite Vitellogenin expression, indicating that the honey bee AMP manipulates mite reproduction upon feeding on bee. Our results provide insights into the mechanism of DWV transmission by the honey bee parasitic mite to the host, and the novel role of AMP in defending against mite infestation.

Decreased progranulin expression in Mycosis fungoides: a possible association with the high frequency of skin infections.

Progranulin (PGRN) is a multi-functional protein known to be involved in diverse biological processes, including tumourigenesis, anti-inflammation, and anti-infection. PGRN expression in sera or tissues is elevated in a variety of malignancies and is associated with poor prognosis. However, it remains to be determined whether PGRN is involved in Mycosis fungoides (MF). To investigate the roles of PGRN in MF. Serum PGRN levels were measured in patients with MF and normal controls by enzyme-linked immunosorbent assay. PGRN expression in MF and normal skin was examined by quantitative reverse transcription polymerase chain reaction and immunohistochemistry. Moreover, we analysed correlations between the expression levels of PGRN and antimicrobial peptides in lesional skin. PGRN levels were significantly lower in sera of MF patients than those of normal controls. PGRN mRNA levels in lesional skin of MF were also significantly decreased. Immunohistochemical staining revealed that PGRN was expressed in epidermal keratinocytes of normal controls, however, PGRN expression in epidermal keratinocytes was also weaker in MF skin. Furthermore, significant inverse correlations were identified between PGRN and antimicrobial peptide mRNA expression. These results suggest that low PGRN expression may contribute to the frequent occurrence of skin infections in patients with MF.

Effect of dietary Sargassum wightii and its fucoidan-rich extract on growth, immunity, disease resistance and antimicrobial peptide gene expression in Labeo rohita

This work aimed to appraise growth performance, immune responsiveness, bacterial disease resistance and mRNA expression of two antimicrobial peptides in Labeo rohita fingerlings fed diets supplemented with seaweed Sargassum wightii and its fucoidan-rich extract. Two hundred and twenty-five fingerlings were divided into five experimental groups in triplicates, each replicate having 15 fish in a 90-L tank. Different groups were fed with isonitrogenous (35% crude protein) and isoenergetic (1408.16 kJ/100 g) diets containing either 0% fucoidan-rich seaweed extract (FRSE), 1% FRSE, 2% FRSE, 3% seaweed powder and 6% seaweed powder for 60 days. Partial nucleotide sequences of the antimicrobial peptides, hepcidin and defensin, were characterized in Labeo rohita fingerlings, and gene expression in the different tissues of experimental fish was studied. The fish-fed FRSE-supplemented diets showed significant increase (P < 0.05) in the mRNA expression of antimicrobial peptides in liver, skin and intestine tissues. Bacterial challenge study using Aeromonas hydrophila showed higher survival in the FRSE-fed groups. Fish-fed FRSE-supplemented diets also showed better non-specific immune response (NBT reduction, serum lysozyme activity, serum albumin: globulin ratio and phagocytic activity) in pre-challenge and post-challenge periods. No significant difference was observed in the growth performance in the different experimental groups. The study indicates that although dietary FRSE is a potential immunostimulant in Labeo rohita fingerlings, it does not improve growth performance.

Interleukin-6/Stat3 signaling has an essential role in the host antimicrobial response to urinary tract infection

The signaling networks regulating antimicrobial activity during urinary tract infection (UTI) are incompletely understood. Interleukin-6 (IL-6) levels increase with UTI severity, but the specific contributions of IL-6 to host immunity against bacterial uropathogens are unknown. To clarify this we tested whether IL-6 activates the Stat3 transcription factor, to drive a program of antimicrobial peptide gene expression in infected urothelium during UTI. Transurethral inoculation of uropathogenic Escherichia coli led to IL-6 secretion, urothelial Stat3 phosphorylation, and activation of antimicrobial peptide transcription, in a Toll-like receptor 4-dependent manner in a murine model of cystitis. Recombinant IL-6 elicited Stat3 phosphorylation in primary urothelial cells invitro, and systemic IL-6 administration promoted urothelial Stat3 phosphorylation and antimicrobial peptide expression invivo. IL-6 deficiency led to decreased urothelial Stat3 phosphorylation and antimicrobial peptide mRNA expression following UTI, a finding mirrored by conditional Stat3 deletion. Deficiency in IL-6 or Stat3 was associated with increased formation of intracellular bacterial communities, and exogenous IL-6 reversed this phenotype in IL-6 knockout mice. Moreover, chronic IL-6 depletion led to increased renal bacterial burden and severe pyelonephritis in C3H/HeOuJ mice. Thus, IL-6/Stat3 signaling drives a transcriptional program of antimicrobial gene expression in infected urothelium, with key roles in limiting epithelial invasion and ascending infection.

Immunomodulatory activity of pidotimod administered with standard antibiotic therapy in children hospitalized for community-acquired pneumonia.

BackgroundSeveral attempts to improve immune function in young children have been made and encouraging results have been collected with pidotimod (PDT), a synthetic dipeptide molecule that seems to have immunomodulatory activity on both innate and adaptive responses. Until now, the effects of PDT on the immune system have only been studied in vivo after long-term administration to evaluate whether its immunomodulatory activity might prevent the development of infections. This study was planned to evaluate the immunomodulatory activity of PDT administered together with standard antibiotic therapy in children hospitalized for community-acquired pneumonia (CAP).MethodsA total of 20 children hospitalized for community-acquired pneumonia (CAP) were randomized at a 1:1 ratio to receive either standard antibiotics plus pidotimod (PDT) or standard antibiotics alone to evaluate the immunomodulatory activity of PDT. Blood samples for the evaluation of immunological parameters were drawn at the time of recruitment (T0) (i.e., before therapy administration), at T3 and T5 (i.e., 3 and 5 days after the initiation of therapy) as well as at T21 (i.e., 7 days after the therapy ended).ResultsFollowing pneumococcal polysaccharide stimulation, the percentage of dendritic cells (DCs) expressing activation and costimulatory molecules was significantly higher in children receiving PDT plus antibiotics than in the controls. A significant increase in tumor necrosis factor-α and/or interleukin-12 secretion and expression of toll like receptor 2 was observed in PDT-treated children compared with controls; this was followed by an increased release of proinflammatory cytokines by monocytes. In the PDT-treated group, mRNA expression of antimicrobial peptides and genes involved in the inflammatory response were also augmented in comparison with the controls.ConclusionsThese results demonstrate, for the first time, that PDT administered together with standard antibiotics is associated with a favorable persistent immunomodulatory effect in children with CAP.

Expression of antimicrobial peptides in the epithelium of the cervix uteri after caesarian section and vaginal birth

The Background: Antimicrobial peptides are first line of defense for mucosa against viruses, bacteria, protozoa and fungi. Meanwhile, expression of antimicrobial peptides in postpartum period has not been studied. Objective: To estimate the expression of mRNA of antimicrobial peptides in epithelium of the cervix uteri after caesarean section and vaginal birth 3 or 4 days after delivery. Materials and methods: The data-sample consisted of 17 women after caesarean section and 46 women after vaginal delivery examined on days 3 or 4 of postpartum period. Quantitative reverse transcription PCR method was used to study mRNA expression of antimicrobial peptides. Statistical analysis was performed using Mann-Whitney criteria. Results: It was shown that higher level of expression of SLPI, HNP3, HD6 and HBD4 in the endocervix was present in women who delivered via caesarean section compared with those who had vaginal delivery. Conclusion: Women who underwent caesarean section exhibited increased expression of antimicrobial peptides compared to those who had vaginal birth. This increased expression can be attributed to multiple reasons such as differences in vaginal microflora restoration, different changes in hormone levels and also due to surgical trauma after operative delivery. The use of antimicrobial peptides can give new opportunities for prophylaxis and treatment of septic complications that occur in postpartum period.

A topical Chinese herbal mixture improves epidermal permeability barrier function in normal murine skin

Chinese herbal medicine (CHM) has been shown to have beneficial effects for both skin disorders with barrier abnormality and as skin care ingredients. Yet, how CHM exerts their benefits is unclear. As most, if not all, inflammatory dermatoses are accompanied by abnormal permeability barrier function, we assessed the effects of topical CHM extracts on epidermal permeability barrier function and their potential mechanisms. Topical CHM accelerated barrier recovery following acute barrier disruption. Epidermal lipid content and mRNA expression of fatty acid and ceramide synthetic enzymes increased following topical CHM treatment in addition to mRNA levels for the epidermal glucosylceramide transport protein, ATP-binding cassette A12. Likewise, CHM extract increased mRNA expression of antimicrobial peptides both in vivo and in vitro. These results demonstrate that the topical CHM extract enhances epidermal permeability barrier function, suggesting that topical CHM could provide an alternative regimen for the prevention/treatment of inflammatory dermatoses accompanied by barrier abnormalities.

Effects of Dietary Vitamin D3 Supplementation on AvBD-1 and chCATH-1 Genes Expression in Chicken

In addition to the important role in maintaining calcium homeostasis, vitamin D3 (VD3) has also been suggested to participate in the regulation of innate and adaptive immune responses in human by enhancing antimicrobial peptides expression. In this study, we investigated the effect of supplementation of 0, 800, 1,600, 3,200 and 6,400 IU/kg of VD3 in the basal diet on the mRNA expression of antimicrobial peptides (AvBD-1 and chCATH-1) in chicken by using quantitative real-time RT-PCR. The supplementation of VD3 in the basal diet could significantly promote the mRNA expression of both AvBD-1 and chCATH-1 genes (P<0.01), which showed dose-dependent response from 800 to 3,200 IU/kg supplementation dose. Compared with control group (0 IU/kg), 11-fold to 39-fold and 4.7-fold to 25-fold of mRNA expression difference in treatment groups were detected for AvBD-1 and chCATH-1 genes in bursa of Fabricius, respectively. In addition, VD3 also could significantly enhance the AvBD-1 and chCATH-1 mRNA expression in thymus (P<0.05). Our results indicated that the VD3 supplementation of 3,200 IU/kg dose in basal diet could significantly promote the vBD-1 and chCATH-1 mRNA expression in bursa of Fabricius, which is potential to improve the innate ability to resist diseases in chicken.

Differences in transcriptomic profile and IgA repertoire between jejunal and ileal Peyer's patches

In many species such as sheep and pig, there are two types of Peyer's patches (PP): several discrete patches in the jejunum and a long and continuous patch in the ileum. Most of the immunoglobulin A in the gut is generated by B-cells in the PP germinal centers. Moreover, swine like ovine ileal PP might be important for antigen independent B-cell repertoire diversification. We examined, by quantitative real-time PCR, the expression of 36 transcripts of antimicrobial peptides, chemokines, interleukines, Toll-like receptors and transcription factors from both PP and we highlighted the differences by a principal component analysis. Ileal PP was characterized by a higher mRNA expression of CCL28, IL5, IL10, TLR2 and TLR4 while jejunal PP showed higher mRNA expression of antimicrobial peptides, CCL25, FOXP3, IL4, T-Bet, TSLP and SOCS2. Then, we analyzed some VDJ rearrangements to assess immunoglobulin repertoire diversity in jejunal and ileal PP from weaned piglets. The IgA and IgM repertoires were more diverse in ileal than in jejunal piglet PP. All these results could be related to the rarefaction of interfollicular T-cell zone and the presence in ileal versus jejunal lumen of a more diversified microflora. These findings shed a light on the functional differences between both PP.

Differential mRNA Expression of Antimicrobial Peptides and Proteins in Atopic Dermatitis as Compared to Psoriasis Vulgaris and Healthy Skin

Background: Patients with atopic dermatitis (AD) are prone to have skin infections. We aimed to investigate mRNA expression levels of various antimicrobial peptides and proteins (AMPs) in AD patients, and compare it with psoriasis vulgaris (PV) patients and healthy subjects. Methods: Skin biopsies were obtained from healthy subjects and patients with AD and PV. Quantitative real-time RT-PCR was used to determine the mRNA levels of human β-defensin (hBD)-1, hBD-2, hBD-3, LL-37, psoriasin, RNase 7, interferon-γ, and interleukin-10 (IL-10). Results: Except for LL-37, mRNA of hBDs, psoriasin, and RNase 7 was significantly higher expressed in AD (n = 42) and/or PV (n = 35) patients when compared to controls (n = 18). While PV lesions showed significantly higher mRNA hBD-2 levels than lesions of AD, the latter was associated with significantly higher mRNA levels of RNase 7 when compared to PV. A significant positive correlation of hBD expression was observed both in AD patients and PV patients. hBD mRNA levels of AD skin correlated with psoriasin and RNase 7 levels. hBD-1 mRNA expression correlated with AD activity and IL-10 mRNA expression. Conclusions: Most AMPs investigated in this study proved to be overexpressed in AD as well as PV when compared to controls. However, a statistically significant difference in AMP mRNA expression between AD and PV was only found for hBD-2 and RNase 7. A moderate-to-strong linear relationship between the mRNA expression of particular AMPs appears to exist in AD, and to a lesser extent in PV as well.

Changes of antimicrobial peptide mRNA expression in atopic eczema following phototherapy

The epidermal expression of antimicrobial peptides (AMPs) such as human beta-defensin (hBD)-2 and cathelicidin LL-37 is downregulated in atopic eczema (AE) as compared with psoriasis. Hence, AMPs may represent important cofactors in the pathogenesis of AE. In the present pilot study we aimed to investigate whether the cutaneous mRNA expression of AMPs is altered in patients with AE following narrowband ultraviolet B (NB-UVB) phototherapy. We studied 12 patients diagnosed with extrinsic AE who underwent a 6-week course of NB-UVB. Skin biopsies were taken from healthy controls (n = 12) and patients with AE at baseline and after the last NB-UVB irradiation. Quantitative real-time reverse transcription-polymerase chain reaction was performed for hBD-1, hBD-2, hBD-3 and LL-37. A significant (P < 0.05) reduction in the clinical score was observed after treatment with NB-UVB. As compared with controls, patients with AE showed a significantly lower hBD-1 mRNA expression and significantly higher hBD-2 levels (P < 0.05). Following NB-UVB treatment of patients with AE we observed a significant increase of hBD-1 expression as well a significant decrease of hBD-2 (P < 0.05). Levels of hBD-3 and LL-37 did not significantly differ between the groups (P > 0.05). The pattern of mRNA expression of constitutive (hBD-1) as well as inducible (hBD-2) AMPs seems to be altered in AE as compared with healthy controls. The resolution of AE lesions following phototherapy is accompanied by significant changes in mRNA expression of hBDs, indicating that AMPs may play a role in the pathogenesis of AE.