ABSTRACT
ObjectiveTo investigate the effect and mechanism of Aconiti Lateralis Radix Praeparata-Cinnamomi Cortex in regulating the intestinal function in the rat model of slow transit constipation （STC） due to yang deficiency via the vasoactive intestinal peptide （VIP）/cathelicidin antimicrobial peptide （cAMP）/protein kinase A （PKA）/aquaporin （AQP） pathway. MethodSD rats were randomized into 6 groups （n=6）， including a control group， a model group， high-， medium-， and low-dose Aconiti Lateralis Radix Praeparata-Cinnamomi Cortex groups， and a prucalopride group. Other groups except the control group were treated with loperamide hydrochloride combined with ice water by gavage for the modeling of STC due to yang deficiency. The number of fecal pellets， time to the first black stool defecation， fecal water content， intestinal propulsion rate， and score of fecal properties were recorded in each group. At the end of the treatment， the colon was stained with hematoxylin-eosin （HE） to reveal the histopathological changes and Alcian blue/periodic acid-Schiff （AB-PAS） to reveal the secretion of colonic mucus. The enzyme-linked immunosorbent assay （ELISA） was employed to measure the level of VIP in the serum. The mRNA level of AQP in the colon was measured by polymerase chain reaction （Real-time PCR）. Immunohistochemical staining was performed to observe the expression of AQPs in the colon and kidney tissues. Western blot was performed to determine the protein levels of cAMP， PKA， and VIP in the colon tissue. ResultCompared with the control group, the model group had longer time to the first black stool defecation, reduced fecal pellets and water content, reduced Bristol Stool Form Scale score and intestinal propulsion rate, and constipation aggravated（P<0.01）. Moreover, increased the intestinal lesions, reduced the mucus secretion, reduce the serum VIP level, up-regulated the expression levels of AQP1 in the colon and kidney tissues, inhibited the expression of AQP3 and AQP9（P<0.01）., and down-regulated the protein levels of cAMP, PKA, and VIP in the colon tissue. Compared with the model group， the high-dose Aconiti Lateralis Radix Praeparata-Cinnamomi Cortex group had shortened time to the first black stool defecation， increased fecal pellets and water content， increased Bristol Stool Form Scale score and intestinal propulsion rate， and alleviated constipation symptoms. Moreover， high-dose Aconiti Lateralis Radix Praeparata-Cinnamomi Cortex reduced the intestinal lesions， increased the mucus secretion， elevated the serum VIP level（P<0.01）.， down-regulated the expression levels of AQP1 in the colon and kidney tissues， promoted the expression of AQP3 and AQP9（P<0.05，P<0.01）， and up-regulated the protein levels of cAMP， PKA， and VIP in the colon tissue. The medium- and low-dose groups had weaker effect than the high-dose group（P<0.01）. ConclusionHigh-dose Aconiti Lateralis Radix Praeparata-Cinnamomi Cortex can improve the intestinal motility and balance the intestinal water and fluid metabolism by up-regulating the VIP/cAMP/PKA/AQP pathway， thereby mitigating the constipation symptoms in the rat model of slow transit constipation due to yang deficiency.
ABSTRACT
Objective:To investigate the counteractive effect of mouse dermal fibroblasts (MdFBs) during their adipogenic differentiation against Staphylococcus aureus infection, and to explore its mechanisms. Methods:MdFBs were obtained from newborn C57BL/6 mice, and their adipogenic differentiation was induced by culture in an adipogenic medium for 48 hours. Real-time fluorescence-based quantitative PCR (RT-PCR) was performed to determine the mRNA expression of cathelicidin antimicrobial peptide (CAMP) on days 0-6 during the adipogenic differentiation of MdFBs, and Western blot analysis to determine the protein expression of CAMP in the culture supernatant of MdFBs during their adipogenic differentiation. MdFBs were divided into 4 groups: co-stimulation group stimulated by S. aureus suspensions and cultured in an adipogenic medium, adipogenic control group cultured in an adipogenic medium, S. aureus-stimulation group stimulated by S. aureus suspensions and cultured in a common medium, and control group stimulated by phosphate-buffered saline and cultured in a common medium; Western blot analysis and RT-PCR were conducted to determine the protein and mRNA expression of CAMP. S. aureus (5 × 10 4 CFU/ml) was cultured with the culture supernatant of MdFBs after 5-day adipogenic differentiation (adipogenic group), and the growth activity was evaluated every 2 hours during 10 - 24 hours after the start of co-culture; S. aureus cultured with the culture supernatant of MdFBs in a common medium served as the normal control group, and that cultured with cell-free culture supernatant served as the negative control group. Differences between groups were assessed using unpaired t-test or analysis of variance. Results:Significant differences were observed in the relative mRNA expression of CAMP among different time points (days 0, 1, 2, 4, and 6) during the adipogenic differentiation of MdFBs (1.14 ± 0.74, 68.04 ± 12.72, 683.12 ± 38.06, 1 390.68 ± 226.21, 454.57 ± 204.12, F = 50.08, P < 0.001) ; the CAMP mRNA expression was significantly higher on days 1, 2, 4, and 6 than on day 0 ( t = 9.09, 31.03, 10.63, 3.85, respectively, all P < 0.05), and showed an initial rise and subsequent fall during days 0 - 6. The CAMP protein expression in the culture supernatant of MdFBs peaked on days 2-5 and subsequently decreased. Significant differences were observed in the mRNA and protein expression of CAMP among the control group, S. aureus-stimulation group, adipogenic control group and co-stimulation group (mRNA: 0.08 ± 0.02, 0.38 ± 0.10, 0.49 ± 0.11, 0.80 ± 0.03, respectively, F = 43.25, P < 0.05; protein: 0.433 ± 0.176, 0.574 ± 0.176, 1.007 ± 0.176, 1.217 ± 0.176, respectively, F = 46.79, P < 0.05), and the relative mRNA and protein expression of CAMP was significantly higher in the co-stimulation group than in the adipogenic control group, S. aureus-stimulation group and control group (all P < 0.05). At 10 hours during culture, the growth activity of S. aureus was significantly lower in the adipogenic group (0.053 ± 0.015) than in the normal control group and negative control group (0.109 ± 0.015, 0.106 ± 0.015, t = 11.30, 13.26, respectively, both P < 0.05) ; during 10 - 24 hours, the growth activity of S. aureus also showed a significant decrease in the adipogenic group compared with the normal control group and negative control group (all P < 0.05) . Conclusion:MdFBs secreted CAMP during the adipogenic differentiation, and could inhibit the proliferation of S. aureus.
ABSTRACT
@#Introduction: Vitamin D deficiency and frequent infections are the two common worldwide phenomenon among elderly. Recent studies have demonstrated that vitamin D regulates the expression of specific endogenous antimicrobial peptides like cathelicidin LL-37 of macrophages and neutrophils, which is active against a broad spectrum of infectious agents. Therefore, the objective of the present study was to determine the level of cathelicidin LL-37 in macrophages of elderly women (classified according to serum 25(OH)D level) after exposure to Vibrio cholera infection and to find out the effect of 1,25(OH)2D added in vitro. Methods: This study was conducted among 40 randomly selected rural elderly women aged between 60 to 70 years of age. Their vitamin D status was assessed by the estimation of serum 25(OH)D and classified into three groups viz. sufficient (14 members), insufficient (13 members), and deficient (13 members). Later, their peripheral blood mononuclear cells (PBMC) were isolated and cultured from fresh blood. 1,25(OH)2D supplementation was given selectively at a dose of 10 ×10-8 M for 72 hours in the culture media; then exposed to infection and screened according to the objectives of this study. Results: Macrophages in all groups, except vitamin D deficient group, responded significantly in terms of LL-37 release during exposure to Vibrio cholera infection. Considering in vitro 1,25(OH)2D, supplementation responded significantly (p<0.05) in all three groups. Conclusion: Vitamin D can be used as a prophylaxis to enhance cathelicidin LL-37 release for all three groups as in the present study.
ABSTRACT
The ongoing COVID -19 pandemic is caused by severe acute respiratory syndrome corona virus -2 (SARS-CoV-2). Since its emergence in Wuhan in Hubei province of China in December 2019, the virus has spread to every continent except Antartica. Currently, there is no registered treatment or vaccine for the disease. In the current scenario of the deadly virus spreading across continents and the absence of a specific treatment of novel corona virus, there is an urgent need to search for alternative strategies to prevent and control the rapid replication of virus. Vitamin D supplementation may reduce the incidence, severity and risk of death from pneumonia (consequent to the cytokine storm) in the current COVID pandemic. Through its effect on innate and adaptive immunity, vitamin D can reduce the risk of viral respiratory tract infections. 1, 25(OH) vitamin D directly stimulates the production of anti-microbial peptides like defensin and Cathelicidin that can reduce the rate of viral replication. In addition, it can also reduce the concentration of pro-inflammatory cytokines that are responsible for causing cytokine storm and resultant fatal pneumonia. In order to reduce the risk of infection especially in developing country like India, it is recommended that people at risk of COVDI19 may be considered for vitamin D supplementation.
ABSTRACT
Abstract Background Antimicrobial peptides are components of the innate immune system. Cathelicidin LL-37 plays an important role in antimicrobial defense, exerts proinflammatory effect and strongly affects the immune system functioning. Our recent study revealed that serum concentration of LL-37 is increased in patients with bipolar disorder. Objectives The aim of this study is to re-evaluate serum LL-37 levels in patients with euthymic bipolar disorder and in healthy controls, matched for anthropometric and body composition parameters. Methods 36 adult patients with euthymic bipolar disorder and 68 non-depressed adults were included into the study. Concentration of LL-37 in serum was assessed using ELISA method. Detailed anthropometric measurements, body composition and biochemical analyses were performed. Results There was a statistically significant difference (p = 0.01) in serum LL-37 level between patients with bipolar disorder (4.97 ± 7.98 ng/mL) and control subjects (1.78 ± 2.69 ng/mL). Discussion Results of this study indicate that LL-37 serum level is increased in euthymic bipolar disorder patients. We found that this increase could not be attributed to analyzed anthropometric or body composition parameters.
Subject(s)
Humans , Male , Female , Adult , Bipolar Disorder , Body Composition/drug effects , Cathelicidins/blood , Tobacco Use Disorder , Bipolar Disorder/metabolism , Body Weights and Measures , Linear Models , Laboratory TestABSTRACT
Objective: To explore the effects of maternal vitamin D deficiency before and during pregnancy on the intestinal flora and cathelicidin antimicrobial peptide (CAMP) in offspring rats. Methods: Twenty-four female Sprague-Dawley rats (8-week-old) were randomly assigned to three groups (n=8 per group), i.e. control group (C group), vitamin D deficiency group (VDD group), and vitamin D supplement group (VDS group). Special diets were used to build the rat models of vitamin D deficiency before and during pregnancy. Maternal 25(OH)D level was detected by liquid chromatography tandem mass spectrometry (LC-MS/MS) at gestational day 14. At the age of 4 weeks in offsprings, the level of 25(OH)D was measured; the faeces were collected for the detection of intestinal flora; the mRNA and protein expression of CAMP were evaluated by real-time quantitative RTPCR and Western blotting, respectively. Results: The rat models of vitamin D deficiency before and during pregnancy were successfully established. The relative abundance of intestinal Lactobacillus in the offspring rats in C group, VDD group and VDS group was 0.050±0.016, 0.028±0.013 and 0.033±0.021, respectively. Compared with C group, the relative abundance of intestinal Lactobacillus in VDD group significantly decreased (P<0.05),and the mRNA and protein expression of colonic CAMP significantly decreased as well (P<0.05). Compared with VDD group, VDS group showed a trend of increase in the abundance of intestinal Lactobacillus; the mRNA expression of colonic CAMP didn't change significantly, but the protein expression of colonic CAMP significantly increased (P<0.05). Conclusion: Vitamin D deficiency during pregnancy results in decreased abundance of intestinal Lactobacilli as well as reduced mRNA and protein expression of colonic CAMP in offspring rats. Vitamin D supplementation significantly improves the protein expression of colonic CAMP and induces a trend of increase in the abundance of intestinal Lactobacilli in offspring rats.
ABSTRACT
Objective@#To investigate the effect and mechanism of the antibacterial peptide cathelicidin secreted by tumor associated macrophages on the growth of colorectal cancer in mice.@*Methods@#Azoxymethane (AOM)/ dextran sodium sulfate (DSS) method was used to establish a mouse model of colitis associated colon cancer. To induce tumor formation, cathelicidin antibody, IgG antibody (positive control) or PBS (negative control) was respectively injected into mice once every 3 days and lasted one month. Then the pictures of mice colon were taken, and the numbers of tumor were counted and evaluated. Expressions of cathelicidin in tumor associated macrophages isolated from tumor and adjacent normal tissues of mice were examined by quantitative RT-PCR (qRT-PCR) and Western blot. Expressions of the tumor proliferating antigen Ki-67, macrophage marker CD68 and cathelicidin in tumor and non-tumor tissues were determined by immunohistochemistry analysis. Apoptosis of cells from tumor tissues was analyzed by using TdT-mediated dUTP nick-end labeling (TUNEL).@*Results@#In colon tumor tissues, cathlicidin strongly expressed in inflammatory cells (macrophages), but weakly expressed in tumor cells. The tumor number and size in mice injected with cathelicidin neutralizing antibody were 4.50±1.18 and (1.74±0.18) mm, respectively, significantly lower than 13.88±1.98 and (3.74±0.38) mm of mice injected with PBS (t=4.07, t=4.72; P< 0.01) and 15.25±1.82 and (3.40±0.36) mm of mice injected with IgG antibody (t=4.96, t=4.08; P<0.01). The Ki-67 positive rate of cells in tumor tissues of mice injected with cathelicidin neutralizing antibody was (28.20±3.44) %, significantly lower than (68.20±3.51) % of mice injected with PBS (t=8.135, P<0.01) and (69.20±3.41) % of mice injected with IgG antibody (t=8.461, P<0.01). Immunohistochemistry analyses showed that the expression of CD68 in tumor tissues of mice injected with cathelicidin antibody was significantly lower than that of mice injected with IgG antibody or PBS. TUNEL result showed that treatment with cathelicidin neutralizing antibody had negligible effect on the apoptosis of tumor cells.@*Conclusions@#Cathelicidin secreted by tumor associated macrophages can promote the growth of colorectal cancer in mice, and neutralizing cathelicidin activity can inhibit the growth and proliferation of colorectal cancer. Cathelicidin mediated promotion of colon cancer proliferation may mainly be exerted by recruiting inflammatory cells such as macrophages into the tumor microenvironment.
ABSTRACT
BACKGROUND: Rosacea is a chronic inflammatory disease characterized by centrofacial erythema. Excess cathelicidin is suggested to be important to the pathophysiology of the disease. Recently, presence of a vitamin D response element was revealed in the cathelicidin gene promoter. OBJECTIVE: The aim of this study was to determine whether vitamin D and cathelicidin are associated with rosacea, both serologically and histopathologically. METHODS: Subjects with rosacea and without chronic skin disorders were enrolled in the patient and control groups, respectively. Serum 25-hydroxy-vitamin D and cathelicidin levels were measured. Tissue expression of cathelicidin and vitamin D receptor were measured with immunostaining-intensity-distribution index. RESULTS: The mean serum 25-hydroxyvitamin D level of patients with rosacea was 12.18±5.65 ng/ml, which is lower than that of the controls (17.41±6.75 ng/ml). Mean serum cathelicidin levels in patients with rosacea and the controls were 85.0±26.1 ng/ml and 55.0±23.3 ng/ml, respectively. Cathelicidin expression in rosacea tissue was significantly higher than that in control tissue (5.21 vs. 4.03). No significant difference was observed in vitamin D receptor expression. CONCLUSION: Higher cathelicidin expression in rosacea supports the hypothesis that an abnormal inflammatory response of the innate immune system is important in pathogenesis of rosacea, but the role of high cathelicidin serum levels is complicated. Serum vitamin D was lower in patients with rosacea, although serum cathelicidin was higher than that of the controls. This suggests that the role of vitamin D level in the pathogenesis of rosacea merits further investigation.
Subject(s)
Humans , Erythema , Immune System , Receptors, Calcitriol , Rosacea , Skin , Vitamin D Response Element , Vitamin D , VitaminsABSTRACT
The platelet-rich plasma (PRP) and antimicrobial peptides neutrophil extract (AMP extract) were prepared from rabbit neutrophils as two autologous blood-derived preparations, which could be applied locally to enhance healing process of tissues. Both preparations were analyzed using the MALDI TOF method for accurate qualitative assay. Growth factors (PDGF and VEGF) and microbicidal protein were reported in PRP. In AMP extract a-defensins, namely; NP-1, -2, -3a, -3b, -4, and -5 and cathelicidins represented among other by 15-kDa antibacterial protein (p15s) were detected. In the second part of our study the influence of antimicrobial extract on macrophages in vitro was tested. Then, degranulation of neutrophils in vitro and generation of reactive intermediates by these cells under the influence of AMP extract were assessed. As estimated, the addition of AMP extract into cultures of macrophages decreased superoxide anion generation after 5 days of incubation. Furthermore, AMP extract inhibited degranulation and respiratory burst in neutrophils, therefore in this regard it suppress proinflammatory effect of two studied populations of leukocytes.
Subject(s)
Cathelicidins , In Vitro Techniques , Intercellular Signaling Peptides and Proteins , Leukocytes , Macrophages , Methods , Neutrophils , Peptides , Platelet-Rich Plasma , Respiratory Burst , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , SuperoxidesABSTRACT
Objective To establish a chemiluminescent immunoassay method for the determination of cathelicidin-BF(BF-30)in rat serum,to provide a fast and simple analytical method for its pharmacokinetic studies,then to investigate the pharmacokinet?ic characteristics of BF-30 in vivo. Methods A chemiluminescent immunoassay method was developed and the matrix effect,preci?sion,accuracy,stability and the dilution effect were evaluated,then the method was used to determine the concentration of BF-30 in rat serum. Results The linear range of BF-30 in rat serum was 0.5-40 ng/ml,and the lowest limit of determination was 0.5 ng/ml. No matrix effect was observed. The RSD of inter-and intra-day precisions were 8.76%-14.15%and 4.91%-11.11%,respectively,and ac?curacy was-1.27%--7.71%. The stability of samples for 13 days and stock solution for 30 days at-20℃were good,and the stability of serum samples after 2 cycles of freeze-thaw met the requirements. There was no dilution effect noted after 40 times sample dilution. Conclusion We heve developed a simple,accurate and reliable method which can be applied to the determination of BF-30 in rat se?rum and following pharmacokinetic study.
ABSTRACT
Objective To establish a chemiluminescent immunoassay method for the determination of cathelicidin-BF (BF-30) in rat serum, to provide a fast and simple analytical method for its pharmacokinetic studies, then to investigate the pharmacokinetic characteristics of BF-30 in vivo. Methods A chemiluminescent immunoassay method was developed and the matrix effect, precision, accuracy, stability and the dilution effect were evaluated, then the method was used to determine the concentration of BF-30 in rat serum. Results The linear range of BF-30 in rat serum was 0.5-40 ng/ml, and the lowest limit of determination was 0.5 ng/ml. No matrix effect was observed. The RSD of inter-and intra-day precisions were 8.76%-14.15% and 4.91%-11.11%, respectively, and accuracy was-1.27%--7.71%. The stability of samples for 13 days and stock solution for 30 days at-20°C were good, and the stability of serum samples after 2 cycles of freeze-thaw met the requirements. There was no dilution effect noted after 40 times sample dilution. Conclusion We heve developed a simple, accurate and reliable method which can be applied to the determination of BF-30 in rat serum and following pharmacokinetic study.
ABSTRACT
Objective To study the inhibitory effect of antimicrobial peptide LL-37 on Candida albicans through its ability to promote the secretion of immune factors by vaginal epithelial cells. Methods (1) LL-37 prokaryotic expression vector pET-Duet/LL-37 was constructed and its expression was induced in Escherichia coli M15. The expressed LL-37 fusion protein was purified and identified by western blot. Antifungal activity of the purified protein was initially identified by Kirby-Bauer (K-B) method. (2) Purified LL-37 protein was added to human vaginal epithelial cells co-cultured with Candida, and inhibitory effect on Candida growth was determined by the glucose consumption method. Interferon γ (IFN-γ), interleukin 10 (IL-10) concentration and IFN-γ/IL-10 ratio were measured by ELISA at different time points. Results (1) LL-37 fusion protein was purified to 96% purity at a concentration of 433.92 μg/ml, and was shown to possess anti-fungal activity confirmed by the K-B method. (2) A Candida-vaginal epithelial cells co-culture system was successfully constructed. LL-37 recombinant protein inhibited the growth of Candida with absorbance values significantly higher in the treatment group compared to the control group at all measured time points (12-hour:3.008±0.003 versus 2.967±0.003, 24-hour:2.941±0.003 versus 2.601±0.003, 48-hour:2.893 ± 0.004 versus 2.409 ± 0.003; all P<0.01). Furthermore, the rate of decrease was also much slower compared to the control group. In both control and experimental groups, IFN-γ and IL-10 secretion levels were observed to rise at first peaking at 24 hours and subsequently decrease. For each time period, IFN-γconcentration in the experimental group was significantly higher at 24 hours compared to the control group [(104.00 ± 1.07) versus (85.17 ± 0.28) pg/ml, P<0.01]. In contrast, IL-10 concentrations were significantly lower than the control group at all time points (P<0.01). IFN-γ/IL-10 ratio was also observed to be significantly higher than the control group at all measured time points (P<0.01). Conclusions (1) Recombinant protein LL-37 could significantly inhibit the growth of Candida. (2) By influencing the secretion of immune factors such as IFN-γ, IL-10, etc, recombinant protein LL-37 is able to adjust vaginal epithelial cells local immunity, and enhance resistance to Candida infection.
ABSTRACT
The skin transcriptome of Bufu bufo gargarizans was determined by conventional methods. A novel full length cDNA coding for a Cathelicidin precursor was identified by transcriptomic data assembling, annotation and blast search of corresponding data banks. According to the known processing methods of Cathelicidin family members, present reported novel Cathelicidin precursor of B. bufo gargarizans might be cleaved at 2 possible sites of the same precursor and generate both BG-CATH25 and BG-CATH29 as mature molecules. The deduced BG-CATH25 and BG-CATH29 were synthesized with purity>95% to evaluate the properties and bactericidal activities. The secondary structural characteristics of both BG-CATH25 and BG-CATH29 in different solutions were determined by Circular Dichroism (CD) Analysis. CD results indicated that random coil conformation were the main structural elements for both BG-CATH25 and BG-CATH29 in different buffer systems. Antimicrobial activities against tested bacterial strains were carried out by plating method. Both BG-CATH25 and BG-CATH29 showed strong antibacterial activities against Aeromonas hydrophila, with MIC values of 1.25, 10 mg•L⁻¹, respectively. However, both of them showed weak bactericidal activities against human pathogenic bacteria, like Escherichia coli (ATCC25922）,Staphylococcus aureus (ATCC25923）and Pseudomonas aeruginosa (ATCC 27853).
ABSTRACT
Aim: Both Cathelicidin and Chemerin are chemo-attractant proteins and possess antimicrobial activity. Sufficient level of Vitamin D is important for optimum response of Cathelicidin for its antimycobacterial activity. Studies on the role of these antimicrobial peptides and their relationship with Vitamin D level are limited in tuberculosis. The aim of this study was to investigate an association of Vitamin D with antimicrobial peptide (Cathelicidin) and an adipokine (Chemerin) in patients with pulmonary tuberculosis (TB). Methods: In a case control study we estimated level of Vitamin D, Chemerin, Cathelicidin and TNF α in pulmonary TB patients (n=22) and healthy endemic controls (n=17) using sandwich ELISA methodology. The study was conducted at Aga Khan University Karachi during 2011. Results: TB group had higher proportion of subjects above median level of Cathelicidin (median test; p=0.034) and fewer number of subjects with Chemerin (median test; p=0.001). Pairwise comparison also showed significant differences between average ranks of Vitamin D vs. Cathelicidin (p<0.0001), Chemerin vs. Cathelicidin (p=0.04) and Vitamin D vs. TNFα (p<0.0001). Cathelicidin was identified as most discriminatory marker between TB disease and healthy group (ROC, AUC 0.780; p=0.007). Conclusion: Our results highlight the role of Cathelicidin as a potential biomarker of active TB disease. The role of Cathelicidin and Chemerin as plausible biomarkers requires further studies in both inflammatory and non-inflammatory conditions.
ABSTRACT
Background: The innate immune response to tuberculosis infection may involve the increased production of nitric oxide and cathelicidin due to the up-regulated expression of the vitamin D receptor (VDR), though this proposed mechanism remains controversial. The aim of this study was to determine how the exposure of human monocytes to Mycobacterium tuberculosis (M. tuberculosis) DNA affects the production of nitric oxide and cathelicidin, as well as the expression of VDR. Methods: This study was performed using monocytes obtained from healthy donors. After 24 h incubation, monocytes were stimulated with M. tuberculosis DNA for 18 h to determine the expression of VDR mRNA and the production of nitric oxide and cathelicidin versus non-stimulated cells (the control group). Results: The expression of VDR mRNA was higher in the monocytes exposed to M. tuberculosis DNA compared to the control group (P = 0.020). Monocytes exposed to M. tuberculosis DNA also showed significantly increased production of nitric oxide and cathelicidin compared to the control group (P = 0.0001; P = 0.028). Conclusion: The stimulation of human monocytes with M. tuberculosis DNA increases the expression of the VDR mRNA and the production of nitric oxide and cathelicidin.
ABSTRACT
PURPOSE: Recent findings of increased cathelicidin protein and its proteolytic fragments in rosacea suggest a pathogenic role for cathelicidin in this disease. The relationship between cathelicidin and protease-activated receptor 2 (PAR-2) is therefore of interest, as PAR-2, expressed principally in keratinocytes, regulates pro-inflammatory cytokine expression in the skin. The purpose of this study was to determine the relationship between expression of PAR-2 and cathelicidin in rosacea and to test the effect of direct PAR-2 activation on cathelicidin expression in keratinocytes. MATERIALS AND METHODS: Samples from 40 patients with clinicopathologic diagnosis of rosacea and facial skin tissue samples from 20 patients with no specific findings or milium without inflammation were retrieved. Intensities of immunohistochemical staining for PAR-2 and cathelicidin were compared between normal and rosacea-affected skin tissues. Additionally, correlations between PAR-2 and cathelicidin staining intensities within rosacea patients were analyzed. In cultured keratinocytes, changes in PAR-2, cathelicidin, and vascular endothelial growth factor (VEGF) mRNA and protein were analyzed after treatment with PAR-2 activating peptide (AP). RESULTS: Cathelicidin expression was significantly higher in rosacea skin tissues than in normal tissues (p<0.001), while PAR-2 expression was not significantly higher in rosacea tissues than in normal skin tissues. A positive correlation between PAR-2 and cathelicidin within rosacea samples was observed (R=0.330, p=0.037). After treatment of PAR-2 AP, both mRNA and protein levels for PAR-2, cathelicidin, and VEGF significantly increased in cultured keratinocytes, compared with PAR-2 control peptide treatment. CONCLUSION: PAR-2 may participate in the pathogenesis of rosacea through activation of cathelicidin LL-37, a mediator of innate immune responses in the skin.
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Antimicrobial Cationic Peptides/metabolism , Cytokines/metabolism , Immunity, Innate , Inflammation/metabolism , Keratinocytes/metabolism , Receptor, PAR-2/metabolism , Rosacea/pathology , Skin/pathology , Vascular Endothelial Growth Factor A/metabolismABSTRACT
Antimicrobial peptides (AMPs) are broad spectrum antibiotics, which mostly act without specific receptors. Identification of AMPs is important in the current scenario of emerging multi-drug resistant bacteria. In the present study, in an attempt to identify new AMPs, myeloid cathelicidin cDNAs were synthesized from buffalo (Bubalus bubalis) bone marrow and were amplified using specific primers. Sequence analysis of cloned cDNAs revealed three novel myeloid cathelicidins. They were named based on the number of active amino acids in the C-terminal region of their predicted peptide sequences as BuMAP-28 (having an additional Gly at position 22nd), BuMAP-29 (having an additional IIe at position 27) and BuMAP-34, compared to BMAP-27, BMAP-28 and BMAP-34 of cattle. The BuMAPs showed 93%, 95% and 87% homology respectively with that of its cattle counterpart. Predicted number of amino acids of the cDNAs was 159, 155 and 157 residues, with cationic C-terminal sequences of 28, 29 and 34, respectively, which correspond to putative antimicrobial domains. Several amino acid substitutions were observed in all the three cathelicidins. The conformation of the peptides was predicted to be alpha helical, having total net positive charge and hydrophobicity, similar to that of BMAPs in cattle. Comparative analysis of the predicted peptides suggested potential antimicrobial activity and the sequence variations detected might enable the peptides to act as effective broad spectrum antimicrobial agents.
Subject(s)
Amino Acid Sequence , Animals , Antimicrobial Cationic Peptides/chemistry , Antimicrobial Cationic Peptides/genetics , Base Sequence , Buffaloes/genetics , Cloning, Molecular , DNA, Complementary/genetics , Molecular Sequence Data , Myeloid Cells/metabolismABSTRACT
Background: During the last decade, a lot of co-morbidities (diabetes, obesity, heart disease, etc.) have been described to be associated with psoriasis, but the exact link at the molecular level is not well-known. Researchers have shown molecular level changes in vitamin D pathway and its relationship to cathelicidin. Aims: To estimate the levels of cathelicidin (LL-37), and vitamin D in psoriasis patients with co-morbidities, and compare them with matched healthy controls. Methods: One hundred consecutive patients with stable plaque psoriasis (psoriasis area and severity index ≥10) with no systemic treatment in the past 3 months were investigated for the serum levels of vitamin D and LL-37, and compared with equal number of matched healthy volunteers. Results: The serum vitamin D levels were significantly lower in patients. Furthermore, the levels of serum LL-37were significantly high. Conclusion: Our study showed that the low serum levels of vitamin D, and higher blood levels of cathelicidin could form a molecular level clue in the pathogenesis of psoriasis patients, who are more likely to develop co-morbidities.
ABSTRACT
Atopic diseases such as atopic dermatitis (AD) are very common in industrialized countries. Up to 15%-30% of all children and 2%-10% of all adults suffer from AD. Already in early disease stages, a defective epidermal barrier is known to contribute to the pathogenesis of AD. Central elements in the epidermal barrier are antimicrobial peptides (AMPs), which are secreted by keratinocytes, sweat gland cells but also infiltrating immune cells. AMPs function as endogenous antibiotics and are able to kill bacteria, viruses, and fungi. Furthermore AMPs act as immune modulators with effects on the innate and adaptive immune system. The probably best studied AMPs in human skin are the defensins and cathelicidin. In atopic diseases the functions of AMPs such as cathelicidin might be impaired and microbial superinfections could serve as cofactors for allergic sensitization. Hence, induction of AMPs could be beneficial in these patients. Cathelicidin which is often referred to its peptide form hCAP18 or LL-37 can be induced by ultraviolet light B (UVB) irradiation and is upregulated in infected and injured skin. The cathelicidin gene carries a vitamin D response element and the vitamin D pathway could therefore be targeted for cathelicidin regulation. As the development and course of atopic diseases might be influenced by vitamin D signaling these pathomechanisms could explain the growing evidence connecting vitamin D to allergic diseases, including AD, allergic rhinitis, food allergies and asthma. In this review the role of vitamin D and the AMP cathelicidin in the pathogenesis of atopic diseases with impaired barrier function will be discussed.
Subject(s)
Adult , Child , Humans , Anti-Bacterial Agents , Antimicrobial Cationic Peptides , Asthma , Bacteria , Defensins , Dermatitis, Atopic , Developed Countries , Food Hypersensitivity , Fungi , Hypersensitivity , Immune System , Keratinocytes , Peptides , Rhinitis , Rhinitis, Allergic, Perennial , Skin , Superinfection , Sweat Glands , Ultraviolet Rays , Vitamin D , Vitamin D Response Element , VitaminsABSTRACT
Inflammatory skin diseases such as atopic dermatitis (AD) and rosacea were complicated by barrier abrogation and deficiency in innate immunity. The first defender of epidermal innate immune response is the antimicrobial peptides (AMPs) that exhibit a broad-spectrum antimicrobial activity against multiple pathogens, including Gram-positive and Gram-negative bacteria, viruses, and fungi. The deficiency of these AMPs in the skin of AD fails to protect our body against virulent pathogen infections. In contrast to AD where there is a suppression of AMPs, rosacea is characterized by overexpression of cathelicidin antimicrobial peptide (CAMP), the products of which result in chronic epidermal inflammation. In this regard, AMP generation that is controlled by a key ceramide metabolite S1P-dependent mechanism could be considered as alternate therapeutic approaches to treat these skin disorders, i.e., Increased S1P levels strongly stimulated the CAMP expression which elevated the antimicrobial activity against multiple pathogens resulting the improved AD patient skin.