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1.
Diabetes Obes Metab ; 17(7): 703-7, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25846481

ABSTRACT

Failure of pancreatic ß cells to compensate for insulin resistance is a prerequisite for the development of type 2 diabetes. Sustained elevated circulating levels of free fatty acids and glucose contribute to ß-cell failure. Selective inhibition of histone deacetylase (HDAC)-3 protects pancreatic ß cells against inflammatory and metabolic insults in vitro. In the present study, we tested the ability of a selective HDAC3 inhibitor, BRD3308, to reduce hyperglycaemia and increase insulin secretion in a rat model of type 2 diabetes. At diabetes onset, an ambulatory hyperglycaemic clamp was performed. HDAC3 inhibition improved hyperglycaemia over the study period without affecting weight gain. At the end of the hyperglycaemic clamp, circulating insulin levels were significantly higher in BRD3308-treated rats. Pancreatic insulin staining and contents were also significantly higher. These findings highlight HDAC3 as a key therapeutic target for ß-cell protection in type 2 diabetes.


Subject(s)
Diabetes Mellitus, Experimental/drug therapy , Histone Deacetylase Inhibitors/metabolism , Histone Deacetylases/metabolism , Obesity/drug therapy , Animals , Blood Glucose/metabolism , Diabetes Mellitus, Experimental/blood , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Fatty Acids, Nonesterified/metabolism , Glucose Clamp Technique , Histone Deacetylase Inhibitors/therapeutic use , Histone Deacetylases/therapeutic use , Hyperglycemia/drug therapy , Insulin/blood , Insulin/metabolism , Insulin Resistance , Insulin Secretion , Insulin-Secreting Cells/metabolism , Male , Obesity/blood , Obesity/complications , Rats , Rats, Zucker , Weight Gain
2.
Eur J Immunol ; 45(3): 865-75, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25404161

ABSTRACT

TL1A is a proinflammatory cytokine, which is prevalent in the gut. High TL1A concentrations are present in patients with inflammatory bowel disease (IBD) and in IBD mouse models. However, the role of TL1A during steady-state conditions is relatively unknown. Here, we used TL1A knockout (KO) mice to analyse the impact of TL1A on the intestinal immune system and gut microbiota. The TL1A KO mice showed reduced amounts of small intestinal intraepithelial TCRγδ(+) and CD8(+) T cells, and reduced expression of the activating receptor NKG2D. Moreover, the TL1A KO mice had significantly reduced body weight and visceral adipose tissue deposits, as well as lower levels of leptin and CXCL1, compared with wild-type mice. Analysis of the gut microbial composition of TL1A KO mice revealed a reduction of caecal Clostridial cluster IV, a change in the Firmicutes/Bacteroidetes ratio in caecum and less Lactobacillus spp. in the mucosal ileum. Our results show that TL1A deficiency impacts on the gut microbial composition and the mucosal immune system, especially the intraepithelial TCRγδ(+) T-cell subset, and that TL1A is involved in the establishment of adipose tissue. This research contributes to a broader understanding of TL1A inhibition, which is increasingly considered for treatment of IBD.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , Clostridium/immunology , Intestinal Mucosa , Lactobacillus/immunology , Receptors, Antigen, T-Cell, gamma-delta/immunology , Tumor Necrosis Factor Ligand Superfamily Member 15/immunology , Adipose Tissue/immunology , Adipose Tissue/pathology , Animals , CD8-Positive T-Lymphocytes/pathology , Chemokine CXCL1/genetics , Chemokine CXCL1/immunology , Inflammatory Bowel Diseases/genetics , Inflammatory Bowel Diseases/immunology , Inflammatory Bowel Diseases/microbiology , Inflammatory Bowel Diseases/pathology , Intestinal Mucosa/immunology , Intestinal Mucosa/microbiology , Intestinal Mucosa/pathology , Mice , Mice, Knockout , NK Cell Lectin-Like Receptor Subfamily K/genetics , NK Cell Lectin-Like Receptor Subfamily K/immunology , Receptors, Antigen, T-Cell, gamma-delta/genetics , Tumor Necrosis Factor Ligand Superfamily Member 15/genetics
3.
Br J Dermatol ; 170(2): 352-9, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24124869

ABSTRACT

BACKGROUND: Toluene-2,5-diamine (PTD) is the most frequently used dye in oxidative hair dyes on the Scandinavian market. However, little is known about immune responses to PTD-containing oxidative hair dyes. OBJECTIVES: To study immune responses induced by PTD-containing hair dyes in mice. METHODS: Immune responses against two different permanent hair dye products containing 1·60% (w/w) and 0·48% (w/w) PTD within the colour gel, and various concentrations of pure PTD were studied. The local inflammatory response was measured by ear swelling and cell infiltration, and T- and B-cell infiltration and proliferation was determined in the draining lymph nodes. RESULTS: Concentration-dependent immune responses were seen to PTD both in the skin and draining lymph nodes. The hair dye containing 1·60% PTD induced strong local inflammation and caused T- and B-cell infiltration and proliferation as well as an increased number of regulatory T cells in the draining lymph nodes. In contrast, the hair dye containing 0·48% PTD induced skin inflammation but only minor responses in the draining lymph nodes. CONCLUSIONS: Consumer-available PTD-containing permanent hair dyes can be potent immune activators inducing both pro- and anti-inflammatory responses. The outcome of the response is dependent on allergen dose, amount of additional allergens and exposure regime.


Subject(s)
Hair Dyes , Immunity, Cellular/drug effects , Phenylenediamines/immunology , Animals , B-Lymphocytes/immunology , Female , Inflammation/immunology , Mice, Inbred C57BL , T-Lymphocytes, Regulatory/immunology
4.
Am J Physiol Endocrinol Metab ; 304(1): E60-73, 2013 Jan 01.
Article in English | MEDLINE | ID: mdl-23115082

ABSTRACT

The enteroendocrine K and L cells are responsible for secretion of glucose-dependent insulinotropic polypeptide (GIP) and glucagon like-peptide 1 (GLP-1), whereas pancreatic α-cells are responsible for secretion of glucagon. In rodents and humans, dysregulation of the secretion of GIP, GLP-1, and glucagon is associated with impaired regulation of metabolism. This study evaluates the consequences of acute removal of Gip- or Gcg-expressing cells on glucose metabolism. Generation of the two diphtheria toxin receptor cellular knockout mice, TgN(GIP.DTR) and TgN(GCG.DTR), allowed us to study effects of acute ablation of K and L cells and α-cells. Diphtheria toxin administration reduced the expression of Gip and content of GIP in the proximal jejunum in TgN(GIP.DTR) and expression of Gcg and content of proglucagon-derived peptides in both proximal jejunum and terminal ileum as well as content of glucagon in pancreas in TgN(GCG.DTR) compared with wild-type mice. GIP response to oral glucose was attenuated following K cell loss, but oral and intraperitoneal glucose tolerances were unaffected. Intraperitoneal glucose tolerance was impaired following combined L cell and α-cell loss and normal following α-cell loss. Oral glucose tolerance was improved following L cell and α-cell loss and supernormal following α-cell loss. We present two mouse models that allow studies of the effects of K cell or L cell and α-cell loss as well as isolated α-cell loss. Our findings show that intraperitoneal glucose tolerance is dependent on an intact L cell mass and underscore the diabetogenic effects of α-cell signaling. Furthermore, the results suggest that K cells are less involved in acute regulation of mouse glucose metabolism than L cells and α-cells.


Subject(s)
Enteroendocrine Cells/physiology , Glucagon-Secreting Cells/physiology , Glucose/metabolism , Animals , Apoptosis/genetics , Apoptosis/physiology , Diphtheria Toxin/genetics , Enteroendocrine Cells/classification , Enteroendocrine Cells/metabolism , Female , Gastric Inhibitory Polypeptide/metabolism , Gene Knockdown Techniques , Genes, Transgenic, Suicide/genetics , Glucagon-Secreting Cells/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Inbred DBA , Mice, Transgenic , Organ Specificity/genetics
5.
Eur J Surg Oncol ; 37(1): 72-9, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21111562

ABSTRACT

AIMS: No valid markers are routinely available to follow disease progression in patients with fibrolamellar hepatocellular carcinoma (FLHCC). We report data suggesting that the vitamin B12 binding protein haptocorrin (HC) may prove a suitable marker. METHODS: We monitored a 15-year-old boy diagnosed to have FLHCC by measuring the common markers alanine aminotransaminase, alkaline phosphatase, lactate dehydrogenase, and bilirubin, as well as vitamin B12 (B12), and the forms of the B12 binding proteins. Tumour biopsies were examined immunohistologically. DNA and RNA were extracted from tumour and normal tissue and examined for content of HC DNA and mRNA. RESULTS: The only markers indicative of disease progression were HC and (B12), levels of which were markedly elevated to 84 (11) nmol/L at the time of diagnosis and returned to values within the reference interval (0.43 (0.33) nmol/L) after an apparently radical removal of the tumour. The disappearance rate of HC followed a biphasic curve, the unsaturated protein displaying a half-life of 2.8 days and B12 and saturated HC one of 13 days. Before each diagnosed relapse, an increased concentration of HC was observed. We found a strong immunoreaction against HC in tumour tissue and a high mRNA expression of HC supporting the notion that HC was tumour derived. CONCLUSIONS: Plasma HC proved to be a useful tumour marker in a patient with FLHCC, and we suggest the use of this protein as a marker of disease progression in these patients.


Subject(s)
Biomarkers, Tumor/blood , Liver Neoplasms/blood , Transcobalamins/analysis , Adolescent , Carcinoma, Hepatocellular/blood , Carcinoma, Hepatocellular/diagnostic imaging , Carcinoma, Hepatocellular/surgery , Disease Progression , Humans , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/surgery , Male , Tomography, X-Ray Computed
6.
Gastroenterol Res Pract ; 2009: 616054, 2009.
Article in English | MEDLINE | ID: mdl-19707516

ABSTRACT

BACKGROUND AND AIMS: In a short-term study, Glucagon-like peptide 2 (GLP-2) has been shown to improve intestinal absorption in short bowel syndrome (SBS) patients. This study describes longitudinal changes in relation to GLP-2 treatment for two years. METHODS: GLP-2, 400 micrograms, s.c.,TID, were offered, to eleven SBS patients keeping parenteral support constant. 72-hour nutritional balance studies were performed at baseline, weeks 13, 26, 52 during two years intermitted by an 8-week washout period. In addition, mucosal morphometrics, renal function (by creatinine clearance), body composition and bone mineral density (by DEXA), biochemical markers of bone turnover (by s-CTX and osteocalcin, PTH and vitamin D), and muscle function (NMR, lungfunction, exercise test) were measured. RESULTS: GLP-2 compliance was >93%. Three of eleven patients did not complete the study. In the remaining 8 patients, GLP-2 significantly reduced the fecal wet weight from approximately 3.0 to approximately 2.0 kg/day. This was accompanied by a decline in the oral wet weight intake, maintaining intestinal wet weight absorption and urinary weight constant. Renal function improved. No significant changes were demonstrated in energy intake or absorption, and GLP-2 did not significantly affect mucosal morphology, body composition, bone mineral density or muscle function. CONCLUSIONS: GLP-2 treatment reduces fecal weight by approximately 1000 g/d and enables SBS patients to maintain their intestinal fluid and electrolyte absorption at lower oral intakes. This was accompanied by a 28% improvement in creatinine clearance.

7.
Gastroenterol Res Pract ; 2009: 425759, 2009.
Article in English | MEDLINE | ID: mdl-19590736

ABSTRACT

BACKGROUND AND AIMS: Glucagon-like peptide 2 (GLP-2) has been shown to improve intestinal absorption in short bowel syndrome (SBS) patients in a short-term study. This study describes safety, compliance, and changes in quality of life in 11 SBS patients at baseline, week 13, 26, and 52 during two years of subcutaneous GLP-2 treatment, 400 microgram TID, intermitted by an 8-week washout period. METHODS: Safety and compliance was evaluated during the admissions. The Sickness Impact Profile (SIP), Short Form 36 (SF 36), and Inflammatory Bowel Disease Questionnaire (IBDQ) evaluated quality of life. RESULTS: The predominant adverse event was transient abdominal discomfort in 5 of 11 patients, but in 2, both suffering from Crohns disease, it progressed to abdominal pain and led to discontinuation of GLP-2 treatment. One had a fibrostenotic lesion electively resected at the jejuno-ascendo-anastomosis. The investigator excluded a patient due to unreliable feedback. Stoma nipple enlargement was seen in all 9 jejunostomy patients. Reported GLP-2 compliance was excellent (>93%). GLP-2 improved the overall quality of life VAS-score (4.1 +/- 2.8 cm versus 6.0 +/- 2.4 cm, P < .01), the overall SIP score (10.3 +/- 8.9% versus 6.2 +/- 9.5%, P < .001), the mental component of the SF-36 (45 +/- 13% versus 53 +/- 11%, P < .05), and the overall IBDQ score (5.1 +/- 0.9 versus 5.4 +/- 0.9, P < .007) in the 8 patients completing the study. CONCLUSIONS: Long-term treatment with GLP-2 is feasible in SBS patients, although caution must be exercised in patients with a history of abdominal pain. Although conclusions cannot be made in a noncontrolled trial, the high reported compliance might reflect a high treatment satisfaction, where the clinical benefits of GLP-2 may outweigh the discomforts of injections.

8.
Br J Pharmacol ; 149(1): 92-9, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16880764

ABSTRACT

BACKGROUND AND PURPOSE: Trefoil factors (TFFs) secreted by mucus-producing cells are essential for the defence of the gastrointestinal mucosa. TFFs probably influence the viscoelastic properties of mucus, but this has not been demonstrated in vivo. We therefore studied the gastric secretion of systemically administered TFF2 and TFF3, and their influence on the viscosity of the secretions. EXPERIMENTAL APPROACH: Mice and rats under general anaesthesia were injected intravenously with human (h) TFF2, hTFF3 (5 mg kg(-1) to mice and 25 mg kg(-1) to rats), murine (m) (125)I-TFF3, or (125)I-hTFF3 (300,000 cpm, mice only). The appearance of TFFs in the gastric mucosa and luminal secretions was analysed by autoradiography, gamma-counting, and ELISA, and the viscosity by rheometry. KEY RESULTS: (125)I-mTFF3 and (125)I-hTFF3 were taken up by secretory cells of the gastrointestinal tract and detected at the gastric mucosal surface 15 min after injection. Stressing the stomach by carbachol (3.5 microg kg(-1)) and pyloric ligation significantly increased the uptake. Injected hTFF2, hTFF3, and mTFF3 were retrieved from the gastric contents after 4 h. In rats, an approximately seven-fold increase in the viscosity was detected after injection of TFF2 compared to the controls, whereas TFF3 did not increase the viscosity. In mice, TFF2 increased the viscosity approximately 4-fold. CONCLUSIONS: These data indicate that systemically administered TFFs are transferred to the gastric lumen in a biologically active form.


Subject(s)
Gastric Mucosa/metabolism , Gastrointestinal Contents/drug effects , Peptides/pharmacology , Animals , Autoradiography , Enzyme-Linked Immunosorbent Assay , Female , Immunohistochemistry , In Situ Hybridization , Injections, Intravenous , Mice , Mice, Inbred C57BL , Peptides/metabolism , Rats , Rats, Wistar , Tissue Distribution , Trefoil Factor-2 , Viscosity/drug effects
9.
Mol Hum Reprod ; 11(8): 543-51, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16100239

ABSTRACT

The epidermal growth factor (EGF) system is ubiquitous in humans and plays fundamental roles in embryogenesis, development, proliferation and differentiation. As the endometrium of fertile women is characterized by proliferation and differentiation, we hypothesize a role for the EGF system. Fourteen premenopausal women had endometrial samples removed on day 6 +/- 1 and day 6 +/- 1 and 12 +/- 1 after ovulation during one menstrual cycle. RNA was extracted and analysed by real-time PCR, and immunohistochemistry was performed to localize the components of the EGF system. Human EGF Receptor 1 (HER1) showed highest expression during the proliferative phase, HER2 and HER4 during the early and HER3 during the late secretory phase. Amphiregulin (AR) and transforming growth factor alpha (TGFalpha) expression is highest in proliferative phase. Heparin binding (HB)-EGF and betacellulin (BCL) show no variation. Epiregulin (EP) is detectable in some samples. EGF is undetectable. HER1, HER2, HER3 and HER4 were localized to the epithelium and glands HER3 and HER4 solely in the secretory phase. Amphiregulin was seen in leucocytes and stromal cells, TGFalpha and betacellulin in the epithelial lining, epiregulin in stromal cells whereas HB-EGF and EGF are undetectable. In conclusions, we observed cyclical expression of the four EGF receptors and two ligands and localized all four receptors and four ligands in endometrial biopsies. This suggests a role for the EGF system in growth of the endometrium.


Subject(s)
Endometrium/metabolism , Epidermal Growth Factor/genetics , ErbB Receptors/genetics , Gene Expression Regulation/physiology , Menstrual Cycle/physiology , Adolescent , Adult , DNA Primers , Epidermal Growth Factor/biosynthesis , ErbB Receptors/biosynthesis , Female , Humans , Immunohistochemistry , RNA, Messenger/metabolism , Transforming Growth Factor alpha/metabolism
10.
Gut ; 53(8): 1145-50, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15247183

ABSTRACT

BACKGROUND: Glucagon-like peptide 2 (GLP-2) is an intestinotrophic mediator with therapeutic potential in conditions with compromised intestinal capacity. However, growth stimulation of the intestinal system may accelerate the growth of existing neoplasms in the intestine. AIMS: In the present study, the effects of GLP-2 treatment on the growth of chemically induced colonic neoplasms were investigated. METHODS: In 210 female C57bl mice, colonic tumours were initially induced with the methylating carcinogen 1,2-dimethylhydrazine (DMH) and mice were then treated with GLP-2. Two months after discontinuation of the carcinogen treatment, 135 of the mice were allocated to one of six groups which were treated twice daily with 25 microg GLP-2, 25 microg Gly2-GLP-2 (stable analogue), or phosphate buffered saline for a short (10 days) or long (one month) period. The remaining 75 mice had a treatment free period of three months and were then allocated to groups subjected to long term treatment, as above. RESULTS: Colonic polyps developed in 100% of the mice, regardless of treatment. Survival data revealed no statistical significant differences among the different groups but histopathological analysis demonstrated a clear and significant increase in tumour load of mice treated with Gly2-GLP-2. The tumour promoting effect of native GLP-2 was less pronounced but the number of small sized polyps increased following long term treatment. CONCLUSIONS: The present results clearly indicate that GLP-2 promotes the growth of mucosal neoplasms. Our findings highlight the need for future investigations on the effects of GLP-2 in conditions needing long time treatment or with increased gastrointestinal cancer susceptibility.


Subject(s)
Colonic Neoplasms/pathology , Peptides/adverse effects , Adenoma/pathology , Adenoma/physiopathology , Animals , Body Weight , Colonic Neoplasms/chemically induced , Colonic Polyps/chemically induced , Colonic Polyps/pathology , Female , Glucagon-Like Peptide 2 , Glucagon-Like Peptides , Intestinal Mucosa/pathology , Intestine, Small/pathology , Mice , Mice, Inbred C57BL , Organ Size
11.
Scand J Clin Lab Invest ; 64(2): 146-56, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15115253

ABSTRACT

BACKGROUND: The trefoil factors (TFF1-3) are cysteine-rich peptides expressed in the gastrointestinal tract where they play a critical role in mucosal protection and repair. The expression is up-regulated at sites of ulceration in various chronic inflammatory diseases. Recently, we presented an ELISA method for measurement of TFF3. The aims of the present study were to develop and evaluate ELISAs for the other two known human trefoil peptides, TFF1 and TFF2, and to carry out a cross-sectional study on serum TFF levels in patients with inflammatory bowel disease (IBD). METHODS: The TFF1-ELISA was based on two polyclonal rabbit antibodies and the TFF2-ELISA on a monoclonal mouse antibody and a polyclonal rabbit antibody. RhTFF1 and 2 were employed to prepare the calibrators. TFF1-3 were assayed in serum from IBD patients (n=41) and controls (n=13). RESULTS: The TFF1- (TFF2-) ELISA had a detection limit of 3 pmol/L (6 pmol/L) and an analytical imprecision (CV(A)) of 7.0-8.8 for mean concentrations of 24-120 pmol/L (6.1-8.0 for mean concentrations of 17-77 pmol/L). The central reference intervals (n=300) were 140-1400 pmol/L (37-190 pmol/L). There was no variation with age and menstrual cycle. Food intake reduced concentrations of TFF1 by approximately 15%, but did not influence concentrations of TFF2. TFF1 and TFF3 were increased in serum from IBD patients. CONCLUSIONS: We have developed assays for measuring TFF1 and TFF2. Finding increased TFF concentrations in serum from IBD patients suggests that measurements of trefoil peptides may be of clinical relevance in IBD.


Subject(s)
Immunoassay/methods , Inflammatory Bowel Diseases/blood , Mucins/blood , Muscle Proteins/blood , Peptides/blood , Proteins/analysis , Adolescent , Adult , Aged , Aging/blood , Enzyme-Linked Immunosorbent Assay , Female , Health , Humans , Male , Middle Aged , Mucins/immunology , Muscle Proteins/immunology , Peptides/immunology , Proteins/immunology , Sensitivity and Specificity , Trefoil Factor-1 , Trefoil Factor-2 , Trefoil Factor-3 , Tumor Suppressor Proteins
12.
Regul Pept ; 115(2): 91-9, 2003 Sep 15.
Article in English | MEDLINE | ID: mdl-12972324

ABSTRACT

Peptides of the trefoil factor family (TFF1, TFF2 and TFF3) are co-secreted with mucus in most organ systems and are believed to interact with mucins to produce high-viscosity, stable gel complexes. We have previously demonstrated that cells in the GI tract possess binding sites to TFF2 and that injected TFF2 ends up in the mucus layer. In the present study, tissue binding and metabolism of parenterally administered human TFF1 and TFF3 in rats were described and compared to the immunohistochemical localization of the TFF peptides. 125I-TFF1 monomer and 125I-TFF3 mono- and dimer were given intravenously to female Wistar rats. The tissue distribution was assessed by gamma counting of organ samples and by autoradiography of histological sections. The degradation of 125I-TFF3 was studied by means of trichloracetic acid (TCA) precipitation and the saturability of the binding by administration of excess unlabelled peptide. The TFF peptides were localized in histologic sections from the GI tract by immunohistochemistry. Injected TFF3 dimer (12%) was taken up by the GI tract. At autoradiography, grains were localized to the same cells that were immunoreactive to TFF2. The binding could be displaced by excess TFF3. Similar binding was observed for the TFF1 and TFF3 monomers apart from binding in the stomach, where the uptake was only 15% in comparison to the dimer. There was no specific binding outside the GI tract and no binding to TFF1 or TFF3 immunoreactive cells. In conclusion, the TFF2-binding cells in the gastrointestinal tract seem to have basolateral, receptor-like activity to all three TFF peptides. The mucous neck cells of the stomach predominantly take up TFFs with two trefoil domains, indicating a different receptor-like activity in the stomach compared to the rest of the GI tract.


Subject(s)
Digestive System/metabolism , Growth Inhibitors/metabolism , Mucins/metabolism , Muscle Proteins/metabolism , Neuropeptides , Peptide Fragments/pharmacology , Peptides/metabolism , Proteins/metabolism , Animals , Cells, Cultured , Estrogens/metabolism , Female , Growth Inhibitors/administration & dosage , Humans , Immunoenzyme Techniques , Injections, Intravenous , Iodine Radioisotopes , Mucins/administration & dosage , Muscle Proteins/administration & dosage , Proteins/administration & dosage , Rats , Rats, Wistar , Tissue Distribution , Trefoil Factor-1 , Trefoil Factor-2 , Trefoil Factor-3 , Tumor Suppressor Proteins
13.
Eur J Clin Invest ; 32(7): 519-27, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12153553

ABSTRACT

BACKGROUND: Trefoil peptides (TFFs) are expressed and secreted in a tissue-specific manner in the gastrointestinal tract. Evidence of coexpression of trefoil peptides and mucins has been demonstrated in most mucus-producing cells in the gastrointestinal tract. The expression of trefoil peptides is up-regulated in gastric ulceration and colitis. It is believed that TFF peptides interact with mucin to increase viscosity but this has never been confirmed. The aims of the present study were to elucidate the direct effect of trefoil peptides on mucus gel formation. MATERIALS AND METHODS: The viscosity of mucin solutions was measured by means of a rotational rheometer after adding three mammalian trefoil peptides: TFF1, TFF2, and TFF3. RESULTS: Adding TFF2 (0.3%) to the mucin solutions (8%) resulted in more than a factor 10 increase in viscosity and elasticity, and the mucin solution was transformed into a gel-like structure with serpentine-like complexes between the mucin and TFF2. The dimer form of TFF3 also increased viscosity but resulted in a spider's web-like structure. The monomer forms of TFF1 and TFF3 had very little effect on the viscosity and elasticity of the mucin solutions. CONCLUSIONS: The addition of TFF2 to mucin solutions results in significantly increased viscosity and elasticity, under which the mucin solutions are transformed into a gel-like state. The ability of some trefoil peptides to catalyse the formation of stable mucin complexes may be one of the ways by which these peptides exert their protective and healing functions.


Subject(s)
Growth Substances/pharmacology , Mucins/physiology , Muscle Proteins , Neuropeptides , Peptides/pharmacology , Proteins , Animals , Cattle , Elasticity/drug effects , Gels , Growth Substances/analysis , Humans , Immunohistochemistry , In Vitro Techniques , Peptides/analysis , Rheology , Sputum , Swine , Trefoil Factor-1 , Trefoil Factor-2 , Trefoil Factor-3 , Tumor Suppressor Proteins , Viscosity/drug effects
14.
Scand J Gastroenterol ; 37(4): 392-8, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11989828

ABSTRACT

BACKGROUND: Glucagon-like peptide 2 (GLP-2) is a newly discovered intestinotrophic hormone. We have recently reported that a 5-week GLP-2 treatment improved the intestinal absorptive capacity of short-bowel patients with no colon. Additionally, GLP-2 treatment was associated with changes in body composition that included a significant increase in total body bone mass. This article describes the effect of GLP-2 on spinal and hip bone mineral density (BMD) and biochemical markers of bone turnover in these patients. METHODS: In an open-labelled pilot study, eight short-bowel patients (3M, 5F; mean age 49 years) with small-bowel resection and no colon received 400 microg s.c. of GLP-2 twice daily for 5 weeks. Four received home parenteral nutrition (mean length of residual jejunum 83 cm) and 4 did not (mean length of ileum resected 106 cm). The outcome measures were the mean percent change from baseline in spinal and hip BMD measured by dual-energy X-ray absorptiometry, changes in four biochemical markers of bone-turnover, PTH, 25-hydroxy vitamin-D, and the intestinal absorption of calcium. RESULTS: Mean +/- s(x) (SEM) percent changes in spinal and hip BMD were 1.1+/-0.4% (P < 0.05) and 1.9+/-0.8% (P = 0.06), respectively. The intestinal calcium absorption increased by 2.7% (P = 0.87). Serum ionized calcium increased in 5/8 patients with a concomitant decrease in serum PTH values. Three of the four markers of bone turnover decreased. CONCLUSION: A 5-week GLP-2 administration significantly increased spinal BMD in short-bowel patients with no colon. The mechanism by which GLP-2 affects bone metabolism remains unclear, but may be related to an increased mineralization of bone resulting from an improved intestinal calcium absorption.


Subject(s)
Bone Density/drug effects , Bone Remodeling/drug effects , Gastrointestinal Hormones/therapeutic use , Glucagon/immunology , Peptides/therapeutic use , Short Bowel Syndrome/physiopathology , Absorptiometry, Photon , Adult , Alkaline Phosphatase/blood , Amino Acids/blood , Bone Diseases, Metabolic/etiology , Calcium/metabolism , Female , Glucagon-Like Peptide 2 , Glucagon-Like Peptides , Hormones/therapeutic use , Humans , Intestinal Absorption/drug effects , Male , Middle Aged , Osteocalcin/blood , Osteoporosis/etiology , Parathyroid Hormone/blood , Pilot Projects , Short Bowel Syndrome/complications , Short Bowel Syndrome/metabolism , Vitamin D/metabolism
15.
BJU Int ; 89(6): 583-90, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11942969

ABSTRACT

OBJECTIVE: To analyse the expression of the epidermal growth factor (EGF) system in prostate tissue and secretions obtained from patients with benign prostatic hyperplasia (BPH) treated with or without finasteride (which primarily targets the androgen-sensitive secretory epithelial cells in the prostate, with little effect on basal epithelial and stromal cells). PATIENTS AND METHODS: The expression of the EGF system was evaluated by enzyme-linked immunosorbent assay and immunohistochemistry in samples of prostate tissue and secretions from patients with BPH randomized for treatment with finasteride or placebo for 3 months before surgery. RESULTS: Prostate tissue expressed the EGF receptor (HER1) and HER2, and the ligands EGF, transforming growth factor alpha (TGFalpha), heparin-binding (HB) EGF, betacellulin and amphiregulin. Treatment with finasteride produced greater concentrations of amphiregulin (P < 0.05) than did placebo, did not change the level of TGFalpha, HER1 and HER2, and tended to decrease the concentration of EGF, betacellulin and HB-EGF in prostate tissue. Using immunohistochemistry, HER1 and TGFalpha were both localized to the basal epithelial cells, and there was a strong positive correlation among the tissue concentrations of HER1, HER2 and TGFalpha. Amphiregulin localized to the luminal secretory epithelium. Prostate secretions contained only EGF, which was at levels approximately 150 times higher than in prostate tissue; treatment with finasteride did not affect the concentration of EGF in prostate secretion. CONCLUSIONS: There were only minor changes in the expression of TGFalpha, HER1 and HER2 after finasteride treatment. This may represent an important system for the continuous growth and homeostasis of the androgen-independent basal epithelial cells in the prostate.


Subject(s)
Epidermal Growth Factor/metabolism , Finasteride/therapeutic use , Intercellular Signaling Peptides and Proteins , Prostatic Hyperplasia/drug therapy , Amphiregulin , Betacellulin , EGF Family of Proteins , ErbB Receptors/metabolism , Glycoproteins/metabolism , Growth Substances/metabolism , Humans , Immunohistochemistry , Male , Prospective Studies , Prostatic Hyperplasia/metabolism , Receptor, ErbB-2/metabolism , Transforming Growth Factor alpha/metabolism
16.
Acta Physiol Scand ; 173(2): 213-22, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11683679

ABSTRACT

The aim of this study was to design and evaluate a modified Ussing chamber, that makes use of constant air suction (modified Ussing air suction chamber, MUAS) for fixation of biopsy specimens. Standard size forceps biopsies were taken from the descending part of duodenum from patients undergoing endoscopy. Short circuit current (SCC) and conductance (G) were measured during basal conditions and after addition of different sugars and secretagogues. Histologic examination was performed to determine the degree of tissue damage after study in the chamber. Basal SCC was 54.7 +/- 4.3 microA x cm(-2) and G was 58.7 +/- 4.7 mS x cm(-2) (mean +/- SEM, n=48) and steady values of these parameters were observed for at least 2 h. Reproducible and steady responses in SCC were obtained with D-glucose (SCCmax=172 +/- 22.1 microA x cm(-2); EC50=6.9 +/- 0.7 mM, n=5) and D-galactose (SCCmax=233 +/- 55.7 microA x cm(-2); EC50=9.2 +/- 0.7 mM, n=3), and secretory responses with 5-hydroxytryptamine, 100 microM (DeltaSCC= 16.1 +/- 3.8 microA x cm(-2), n=10), histamine, 100 microM (DeltaSCC=24.0 +/- 4.1 microA x cm(-2), n=10) and prostaglandin E2, 1 microM (DeltaSCC=30.3 +/- 5.4 microA x cm(-2), n=6). Experimental biopsy specimens showed intact surface epithelium by histologic examination and did not differ from controls apart from minor indications of edge damage. No difference in basal electrical parameters and D-glucose fluxes were found between Helicobacter pylori positive and negative patients. Our data suggests that the MUAS chamber represents a promising alternative approach to measure transport processes in intestinal endoscopic biopsies.


Subject(s)
Diffusion Chambers, Culture/instrumentation , Duodenum/metabolism , Intestinal Absorption/physiology , Adult , Aged , Biopsy , Dinoprostone/pharmacology , Duodenum/microbiology , Endoscopy, Digestive System , Fructose/pharmacology , Galactose/pharmacokinetics , Glucose/pharmacokinetics , Helicobacter Infections/metabolism , Helicobacter Infections/pathology , Helicobacter pylori , Histamine/pharmacology , Humans , Intestinal Absorption/drug effects , Intestinal Mucosa/metabolism , Intestinal Mucosa/microbiology , Middle Aged , Serotonin/pharmacology , Water/metabolism
17.
Neurogastroenterol Motil ; 13(4): 353-9, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11576394

ABSTRACT

We studied the effect of porcine CGRP (pCGRP) in concentrations from 10(-10) to 10(-8) mol L(-1) on the motility and on the release of substance P, neurokinin A, somatostatin and gastrin in the antrum using the isolated perfused porcine antrum as experimental model. In addition, we studied the localization of CGRP by immunohistochemistry in the porcine antrum. CGRP-immunoreactive nerve fibres were found mainly in the submucous layer and in the external muscle coat, where they were seen in all layers, and in the ganglia of the myenteric nervous plexus. The frequency of contraction was significantly and dose-dependently increased from a basal level of 11.8 +/- 0.5 contractions per 5 min to 24.4 +/- 3.6 contractions per 5 min at pCGRP 10(-8) mol L(-1). At this dose, the release of substance P and neurokinin A was significantly increased to 470 +/- 149% and 217 +/- 26%, respectively, compared to basal release. The effect of pCGRP was unaffected by the addition of the nonpeptide antagonists for the NK-1 (CP-99994) and NK-2 receptors (SR48968), both at 10(-6) mol L(-1), whereas atropine (10(-6) mol L(-1)) completely abolished the motor effect of pCGRP. The release of somatostatin was significantly increased by 154 +/- 15% in response to CGRP at 10(-8) mol L(-1). The release of gastrin was unaffected by pCGRP. In conclusion, pCGRP increases contractile activity in the porcine antrum, an effect that involves cholinergic mechanisms but is independent of the release of substance P and neurokinin A. in addition, pCGRP increases the release of somatostatin but has no effect on gastrin release in the isolated perfused porcine antrum.


Subject(s)
Calcitonin Gene-Related Peptide/pharmacology , Gastrins/metabolism , Gastrointestinal Motility/drug effects , Neurokinin A/metabolism , Pyloric Antrum/physiology , Somatostatin/metabolism , Substance P/metabolism , Animals , Calcitonin Gene-Related Peptide/metabolism , Immunohistochemistry , In Vitro Techniques , Perfusion , Pyloric Antrum/drug effects , Swine
18.
Cancer Res ; 61(16): 6227-33, 2001 Aug 15.
Article in English | MEDLINE | ID: mdl-11507076

ABSTRACT

Members of the epidermal growth factor (EGF) family have been suggested as prognostic markers in patients with bladder cancer. Thus far, there has been no consensus on their usefulness. We report an analysis of six ligands and two receptors of which a subset correlate to tumor stage and survival. Biopsies from bladder cancer tumors were obtained from 73 patients followed for a median of 28 months. The mRNA content for six ligands [EGF, transforming growth factor alpha (TGF-alpha), amphiregulin (AR), betacellulin (betaCL), heparin-binding EGF-like growth factor (HB-EGF), epiregulin (EPI)] and two receptors [EGF receptor I Human EGF Receptor (HER1) and 2 (HER2)] was examined by a newly developed quantitative reverse transcription-PCR method. Five ligands and two receptors (HER1 and HER2) were present in median concentrations of (10(-21) mol/microg RNA) 0.39 (AR), 11 (betaCL), 2.4 (EPI), 40 (HB-EGF), 1.4 (TGF-alpha), 75 (HER1), and 39,000 (HER2). EGF was barely detectable. A significantly higher expression of EPI (P < 0.001), HB-EGF (P < 0.001), and TGF-alpha (P < 0.05) were observed in T2-T4 tumors as compared with Ta tumors. Especially the expression of EPI mRNA correlated strongly to survival (P < 0.0005), but increased expression of TGF-alpha (P < 0.005), AR, and HB-EGF (P < 0.02) was also associated with a reduced life span. For the first time, mRNA expression of six ligands and two receptors of the EGF family have been examined in bladder cancer tumors. Our data emphasize that members of the EGF family, especially EPI, may be potential bladder tumor markers.


Subject(s)
Biomarkers, Tumor/biosynthesis , Epidermal Growth Factor/biosynthesis , ErbB Receptors/metabolism , Intercellular Signaling Peptides and Proteins , Urinary Bladder Neoplasms/metabolism , Adult , Aged , Aged, 80 and over , Amphiregulin , Betacellulin , Biomarkers, Tumor/genetics , EGF Family of Proteins , Epidermal Growth Factor/genetics , Epiregulin , ErbB Receptors/biosynthesis , ErbB Receptors/genetics , Female , Glycoproteins/biosynthesis , Glycoproteins/genetics , Growth Substances/biosynthesis , Growth Substances/genetics , Humans , Immunohistochemistry , Ligands , Male , Middle Aged , Prognosis , Prospective Studies , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Receptor, ErbB-2/biosynthesis , Receptor, ErbB-2/genetics , Transforming Growth Factor alpha/biosynthesis , Transforming Growth Factor alpha/genetics , Urinary Bladder Neoplasms/genetics , Urinary Bladder Neoplasms/pathology
19.
Eur J Endocrinol ; 145(2): 147-53, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11454509

ABSTRACT

OBJECTIVE: To evaluate the histomorphology of skin and its appendages, especially eccrine sweat glands, in patients with GH disorders, because reduced sweating ability in patients with growth hormone deficiency (GHD) is associated with increased risk of hyperthermia under stressed conditions. DESIGN AND METHODS: A skin biopsy was obtained from 17 patients with GHD treated with GH, five patients with untreated GHD, 10 patients with active acromegaly and 13 healthy controls. RESULTS: The sweat secretion rate (SSR) was significantly decreased in both the untreated (median 41 mg/30 min, range 9-79 mg/30 min) and the GH-treated (median 98 mg/30 min, range 28-147 mg/30 min) patients with GHD compared with that in controls (median 119 mg/30 min, range 90-189 mg/30 min; P=0.001 and 0.01 respectively). Epidermal thickness was significantly decreased in both untreated (median 39 microm, range 28-55 microm) and GH-treated patients with GHD (median 53 microm, range 37-100 microm), compared with that in controls (median 66 microm, range 40-111 microm; P<0.02). A statistically non-significant tendency towards thinner epidermis (median 59 microm, range 33-83 microm) was recorded in acromegalic patients (P=0.08) compared with controls. There was no significant difference in the area of the sebaceous glands in the biopsies between the three groups and the controls. The area of eccrine sweat gland glomeruli was significantly decreased in the untreated patients with GHD (median 16407 microm2, range 12758-43976 microm2) compared with that in controls (median 29446 microm2, range 13511-128661 microm2; P=0.03), but there was no significant difference between the GH-treated patients with GHD and controls. CONCLUSIONS: We conclude that GH, either directly or via IGF-I, may have both a structural and a functional effect on human skin and its appendages, and that patients with GHD have histomorphological changes in skin compared with controls. Importantly, these changes are not fully reversed despite long-term and adequate GH treatment in patients with childhood onset GHD.


Subject(s)
Acromegaly/pathology , Human Growth Hormone/deficiency , Skin/pathology , Acromegaly/physiopathology , Adolescent , Adult , Biopsy , Eccrine Glands/pathology , Eccrine Glands/physiopathology , Epidermis/pathology , Humans , Insulin-Like Growth Factor Binding Protein 3/blood , Insulin-Like Growth Factor I/metabolism , Iontophoresis , Male , Middle Aged , Muscarinic Agonists/pharmacology , Pilocarpine/pharmacology , Sebaceous Glands/pathology , Sweating/physiology
20.
Dig Dis Sci ; 46(2): 379-88, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11281189

ABSTRACT

Glucagon-like peptide 2 (GLP-2), produced by enteroendocrine L-cells, regulates intestinal growth. This study investigates circulating and intestinal GLP-2 levels in conditions with altered L-cell exposure to nutrients. Rats were allocated to the following experimental groups: ileal-jejunal transposition, resection of the proximal or distal half of the small intestine, and appropriate sham-operated controls. After two weeks, ileal-jejunal transposition led to pronounced growth of the transposed segment and also of the remaining intestinal segments. Plasma GLP-2 levels increased twofold, whereas GLP-2 levels in the intestinal segments were unchanged. In resected rats with reduced intestinal capacity, adaptive small bowel growth was more pronounced following proximal resection than distal small bowel resection. Circulating GLP-2 levels increased threefold in proximally resected animals, and twofold in the distally resected group. Tissue GLP-2 levels were unchanged in resected rats. The data indicate that transposition of a distal part of the small intestine, and thereby exposure of L cells to a more nutrient-rich chyme, leads to intestinal growth. The adaptive intestinal growth is associated with increased plasma levels of GLP-2, and GLP-2 seems to act in an endocrine as well as a paracrine manner.


Subject(s)
Adaptation, Physiological/physiology , Ileum , Jejunum , Models, Animal , Peptides/blood , Peptides/physiology , Animals , Body Weight , Energy Intake , Enteroendocrine Cells/physiology , Female , Glucagon-Like Peptide 2 , Glucagon-Like Peptides , Ileum/chemistry , Ileum/growth & development , Ileum/surgery , Ileum/transplantation , Jejunum/chemistry , Jejunum/growth & development , Jejunum/surgery , Jejunum/transplantation , Peptides/analysis , Rats , Rats, Wistar
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