Transglutaminase Levels Research Articles

Proteomic analysis revealing mechanisms of κ-carrageenan modulating the gelling properties of heat-induced microbial transglutaminase cross-linked myofibrillar protein gels

The effects of κ-carrageenan (KC, 0.2 %, w/w) on the gelling properties and microstructures of heat-treated myofibrillar protein (MP) gels mediated by various levels (0, 0.1, 0.3, and 0.5 %, w/w) of microbial transglutaminase (TG) were investigated. The results revealed that regardless of TG level, the existence of KC significantly promoted the forming of disulphide bonds but limited the generation of large-sized protein polymers in MP gel treated with TG alone, as well as subsequently enhanced the water retention ability and gel strength of mixed MP gel, especially in the sample adding 0.3% TG and 0.2% KC, which was clearly verified by the forming of more denser and continuous gel network. Moreover, TG-induced changes in protein structure led to the alteration in the protein profiles of different MP gels, and an obvious down-regulation trend of myosin (Q9TV63, Q9TV62, P79293, and Q9TV61) was identified in the TG-0.3 group. Furthermore, liquid chromatography–tandem mass spectrometry analysis demonstrated that TG mainly induces protein crosslinking in the light meromyosin domain of the myosin rod. Meanwhile, in the presence of KC, the crosslinking-site percentage of the TG-0.3 group decreased from 37.7% to 36.2%, indicating that KC potentially reduces TG-induced crosslinking in MP gels. Thus, our findings illustrate the critical mechanisms underlying the modulation of KC on the gelling properties of TG-mediated MP gels at the molecular level, which providing potential guideline for the combined applications of TG and KC in the meat industry.

Mechanisms and effects of different crosslinking degrees on gelling properties and in vitro digestibility of heat-induced microbial transglutaminase-mediated myofibrillar protein gels with or without κ-carrageenan

This study investigated the effects of different levels (0, 0.1, 0.3, and 0.5 %, w/w) of microbial transglutaminase (TG) on the gelling properties and in vitro digestibility of heat-induced myofibrillar protein (MP) gels with or without κ-carrageenan (KC, 0.2 %, w/w). The results indicate that the crosslinking degree of MP gels was gradually enhanced with increasing levels of TG alone (P < 0.05). However, regardless of TG level, KC incorporation effectively inhibited TG-induced crosslinking through the steric effect and subsequently promoted the water-holding capacity, gelling properties and rheological characteristics of the MP gels (P < 0.05), as well as led to the development of a more uniform and denser gel network structure. Moreover, compared with the MP gels with TG alone, KC addition increased the presence of hydrogen bonds, hydrophobic interactions, and disulphide bonds among the gels (P < 0.05). Additionally, the existence of KC significantly decreased the in vitro digestibility of TG-mediated MP gels mainly because TG-induced crosslinking promoted physical interaction between KC and MP. Therefore, the present study provides essential information regarding the influence of KC on the gelling properties and in vitro digestibility of heat-induced TG-mediated MP gels.

Celiac disease diagnosis: transglutaminase, duodenal biopsy and genetic tests correlations.

Celiac disease (CD) is an autoimmune enteropathy triggered by gluten ingestion in genetically susceptible individuals. The haplotypes HLA-DQ2 and DQ8, transglutaminase (TGA) antibodies, and biopsy findings are the main tests performed in the evaluation and CD diagnosis. The objective was to establish possible correlations between transglutaminase levels, genetic markers tests, and qualitative intestinal biopsy findings (modified Marsh classification) at the diagnosis. A retrospective cohort study. The selection criteria were confirmed CD cases with genetic tests performed. Statistical analysis was done mainly through One-way ANOVA, Kendall's correlation coefficient (T), and linear regression. The study included 112 patients, with a mean age of 6 ± 4 years. All cases were tested to HLA-DQ2, and it was positive in 93%. HLA-DQ8 was tested in 73% of cases and it was positive in 61%. The percentage of negative genetic markers (DQ2/DQ8) was 4.5% for patients tested to both haplotypes. A comparison of DQ2/DQ8 (positive and negative) with clinical findings and tests performed did not identify any differences for most of the parameters analyzed. Cases of type I diabetes presented significant negative expression for DQ2(-); p = 0.05 and positive expression for DQ8(+); p = 0.023. The TGA antibody levels ranged from 18 to 36,745 U/ml. An inverse correlation was found between age and TGA-L level (p = 0.043). In 23% of the cases, the TGA levels were greater than 1,000 U/ml and presented a moderate positive correlation with the atrophy biopsy profile (T = 0.245). Patients with an atrophic biopsy profile (Marsh III) had a moderate positive correlation with growth failure (T = 0.218) but a negative correlation with constipation (T = -0.277). In terms of diagnosis tests for CD, transglutaminase levels and age presented an inverse correlation, with the level decreasing as age increased. A moderately positive correlation was found between mean transglutaminase with intestinal atrophy and growth retardation. The genetic test DQ2 was positive for 93% and negative genetic markers (DQ2/DQ8) represented 4.5% of cases studied.

Measured levels of positive transglutaminase 2 antibodies are not associated with presentation or incidental endoscopic findings at celiac disease diagnosis

Objectives It has been suggested that celiac disease could be diagnosed non-invasively in adults with transglutaminase antibody (TGA) levels >10x upper limit of normal (ULN). It is, however, unclear if high values signify more advanced disease and higher risk of co-morbidities. We investigated the association between the TGA levels, clinical characteristics and non-celiac endoscopic findings. Methods Medical data on 450 celiac disease patients at diagnosis were collected. They were further divided into those with high positive (>10x ULN, n = 164), moderately positive (1–10x ULN, n = 219), and negative (n = 67) TGA. Results Median age of patients was 50 years and 60% were women. Patients with negative TGA were older (median age 58 vs. 51 vs. 46 years respectively, p = 0.002) and had more often weight loss (27% vs. 10% vs. 9%, p < 0.001) and abdominal pain or dyspepsia (40% vs 27% vs. 22%, p = 0.017) than did those with moderately positive/high TGA. The groups did not differ in sex, BMI, or other symptoms. Major endoscopic findings included one esophageal adenocarcinoma presenting with dysphagia, six esophagitis, three gastric ulcers, and 39 H. Pylori or other active gastritis. High, moderately positive or negative TGA levels were not associated with these findings in crude or age-adjusted analyses. Conclusions Presentation was similar in patients with moderate or high levels of TGA, whereas patients with negative TGA were different. The level of TGA was not associated with incidental endoscopic findings and the only malignancy presented with an alarm symptom atypical to celiac disease.

Effect of Transglutaminase Treatment on the Structure and Sensory Properties of Rice- or Soy-Based Hybrid Sausages.

Partial substitution of meat with non-protein sources in hybrid meat products generally leads to a decrease in texture attributes and, consequently, in sensory acceptance. In this study, we investigated the effects of transglutaminase (TG) at two concentrations (0.25% and 0.5%) on the physicochemical, textural, and sensory properties of hybrid sausages formulated with concentrated soy or rice proteins. TG caused a reduction in the heat treatment yield of hybrid sausages, particularly those made with rice protein. pH and color parameters were marginally affected by TG addition. Texture parameters increased substantially with TG, although escalating the TG level from 0.25% to 0.5% did not result in a proportional improvement in texture parameters; in fact, for rice-based hybrid sausages, no difference was achieved for all attributes, while only cohesiveness and chewiness were improved for soy-based ones. TG enhanced the sensory attributes of soy-based hybrid sausages to a level comparable to control meat emulsion, as evidenced by ordinate preference score and projective mapping. Our findings suggest that TG is a viable strategy for enhancing texture and sensory parameters in hybrid sausages, particularly for plant proteins that exhibit greater compatibility with the meat matrix.

Cost-benefits and environmental impact of the no-biopsy approach for the diagnosis of coeliac disease in adults

ObjectiveRecent evidence suggests that adult patients with IgA tissue transglutaminase levels of ≥10× the upper limit of normal could be accurately diagnosed with coeliac disease without undergoing endoscopy and biopsy....

Elevated tissue transglutaminase levels in aqueous humor of congenital cataractous eyes with long axial length

ObjectiveTo investigate the distribution of axial length (AL) and posterior staphyloma (PS) in congenital cataract (CC) patients. The correlation between AL and the concentration of tissue transglutaminase (TGM2) in the aqueous humor (AH) of cataractous eyes was also evaluated. MethodsCross-sectional data were collected from 499 children with CC who underwent phacoemulsification, anterior vitrectomy, and IOL implantation. AL measured by IOLMaster or A-scan ultrasonography and the presence of PS examined by B-scan ultrasonography were recorded. TGM2 levels in AH of 15 CC patients with normal axial length (NAL) and 15 CC patients with PS or long axial length (LAL) were measured by enzyme-linked immunosorbent assay. ResultsThe presence of PS in congenital cataractous eyes was 11.02%, and the presence of PS + LAL in congenital cataractous eyes was 29.06%. The AH levels of TGM2 in the cataractous group with NAL were lower than those in the cataractous group with PS or LAL (P < 0.001). The concentration of TGM2 in AH were positively correlated with AL of the patients’ eyes (P = 0.001). Additionally, we found that TGM2 expressed in the cytoplasm of lens epithelial cells of cataractous eyes, and the expression level increased with the AL value. ConclusionsThis study begins to lay the groundwork for investigating the characteristics of PS and LAL in patients with CC. Furthermore, AL was positively correlated with AH levels of TGM2.

Characterization and Short-Term Outcome of Potential Celiac Disease in Children.

Background and Objectives: Potential Celiac Disease (PCD) is defined by positive celiac serology without villous atrophy. We aimed to describe the short-term outcome of pediatric PCD while consuming a gluten-containing diet (GCD). Materials and Methods: Retrospective analysis of pediatric PCD patients continuing GCD, between December 2018-January 2022. Baseline demographics, celiac serology and duodenal biopsy results were reviewed. Follow-up data included repeated serology and biopsy results when performed. Minimum follow-up was 12 months unless celiac disease (CeD) was diagnosed earlier. Results: PCD was diagnosed in 90 children (71% females) with a mean age of 7.2 (range 1.8-16.5) years. Baseline anti-tissue transglutaminase (TTG) levels were above 10 times the upper limit of normal (ULN) in 17/90 (18.9%), 3-10 × ULN in 56/90 (62.2%) and 1-3 × ULN in 17/90 (18.9%). During follow-up, the mean time was 17.6 (range 5-35) months, TTG normalized in 34/90 (37.8%), was stable in 48/90 (53.3%), and increased or remained >10 × ULN in 8/90 (8.9%). In 20/90 (22.2%) patients, a repeat endoscopy was performed, leading to CeD diagnosis in 12/20 (60%). Thus, at the end of follow-up, CeD was diagnosed in 12/90 (13.3%). In patients with TTG >10 × ULN at diagnosis, TTG normalized in 5/17, decreased to 3-10 × ULN in 8/17, and remained above 10 × ULN in 4/17. Conclusions: During the short-term follow-up of pediatric PCD patients, less than 15% progressed to CeD. A third had normalized TTG levels, including children with TTG >10 × ULN, indicating the need for periodic serological and histological follow-up among PCD patients.

Transglutaminase crosslinked fish gelatins for emulsion stabilization: From conventional to Pickering emulsions

Gelatin-stabilized emulsions, including conventional and Pickering emulsions, are gaining popularity. In this study, fish gelatins (FG) were modified with transglutaminase (TG) to prepare gelatin molecules, microgels, and their mixtures. The transition of emulsions from conventional to Pickering was observed as gelatins evolved from molecules to microgels. FG (3%) was cross-linked with TG at 0–30 U/g. FG evolved from gelatin molecules into thermo-irreversible hydrogels as TG increased. Without TG or at a low level of TG (10 U/g), FG mainly existed as gelatin molecules that were liquid at 25 °C. At high levels of TG (20 or 30 U/g), FG crosslinked and developed thermo-irreversible chemical hydrogels that were solid. As the concentration of TG increased, the protein molecular weights, zeta potentials, and surface hydrophobicity were significantly increased. Microfluidization was employed to prepare gelatin microgels. Different states of gelatins were mixed with sunflower oil to prepare conventional emulsions, Pickering emulsions, and mixtures. With increased TG, the emulsion droplets became more homogeneous, and protein networks formed around the oil droplets. Emulsions stabilized with modified FG displayed improved physical stability than those stabilized with unmodified FG. At 10 °C, the emulsions stabilized by a mixture of FG molecules and microgels presented higher physical stability. At 25 °C, Pickering emulsions stabilized by microgels showed improved anti-coalescence. The results of this work could provide valuable references for applying gelatin-stabilized conventional or Pickering emulsions with tunable properties, hence increasing the formulation flexibility of gelatin-based food products.

Royal jelly mediates fibrotic signaling, collagen cross-linking and cell proliferation in cardiac fibroblasts

Royal jelly (RJ) is a multifunctional bee product with a unique composition and wide-ranging biological properties, including antioxidant, anti-inflammatory and antiproliferative activities. Still, little is known about the possible myocardial protective properties of RJ. Considering that sonication could enhance RJ bioactivity, this study aimed to assess the effects of non-sonicated (NS) and sonicated (S) RJ on fibrotic signaling, cell proliferation, and collagen production in cardiac fibroblasts. S-RJ was produced by ultrasonication at 20 kHz. Ventricular fibroblasts isolated from neonatal rats were cultured and treated with different concentrations of NS-RJ or S-RJ (0, 50, 100, 150, 200, and 250 µg/well). S-RJ significantly depressed the expression levels of transglutaminase 2 (TG2) mRNA across all the concentrations tested and was inversely associated with the expression of this profibrotic marker. S-RJ and NS-RJ displayed distinct dose-dependent effects on mRNA expression of several other profibrotic, proliferation, and apoptotic markers. Unlike NS-RJ, S-RJ elicited strong negative dose-dependent relationships with the expression of profibrotic markers (TG2, COL1A1, COL3A1, FN1, CTGF, MMP-2, α-SMA, TGF-β1, CX43, periostin), as well as proliferation (CCND1) and apoptotic (BAX, BAX/BCL-2) markers, indicating that RJ dose-response effects were significantly modified by sonification. NS-RJ and S-RJ increased the content of soluble collagen, while decreasing collagen cross-linking. Collectively, these findings show that S-RJ has a greater range of action than NS-RJ for downregulating the expression of biomarkers associated with cardiac fibrosis. Reduced biomarker expression and collagen cross-linkages upon cardiac fibroblast treatment with specific concentrations of S-RJ or NS-RJ suggests putative roles and mechanisms by which RJ may confer some protection against cardiac fibrosis.

Microbial Transglutaminase Cross-Linking Enhances the Textural and Rheological Properties of the Surimi-like Gels Made from Alkali-Extracted Protein Isolate from Catfish Byproducts and the Role of Disulfide Bonds in Gelling.

The texture of surimi-like gels made from the protein isolate extracted from catfish byproducts has been proven to be brittle and lack elasticity. To address this issue, varying levels of microbial transglutaminase (MTGase) from 0.1 to 0.6 units/g were applied. MTGase had little effect on the color profile of gels. When MTGase at 0.5 units/g was employed, hardness, cohesiveness, springiness, chewiness, resilience, fracturablity, and deformation were increased by 218, 55, 12, 451, 115, 446, and 71%, respectively. A further increase in added MTGase did not lead to any textural improvement. In comparison to the gels made from fillet mince, the gels made from protein isolate were still lower in cohesiveness. Due to the activated endogenous transglutaminase, a setting step enhanced the textural properties of gels made from fillet mince. However, because of the endogenous proteases-induced protein degradation, the setting step led to a texture deterioration of the gels made from protein isolate. Gels made from protein isolate showed 23-55% higher solubility in reducing solution than in non-reducing solution, suggesting the vital role of disulfide bonds in the gelation process. Due to the different protein composition and conformation, fillet mince and protein isolate exhibited distinct rheological properties. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed the highly denatured protein isolate was susceptible to proteolysis and prone to disulfide formation during the gelation process. It also revealed that MTGase had an inhibitory effect on the proteolysis induced by endogenous enzymes. In view of the susceptibility of the protein isolate to proteolysis during gelation, future research should consider including other enzyme inhibitory agents in the presence of MTGase to improve the gel texture.

Effect of helicobacter pylori infection eradication on serum level of anti-tissue transglutaminase in children with celiac disease

BackgroundEvidence shows the increase of anti-tissue transglutaminase (tTG) levels in various conditions, including infectious agents, independently of celiac disease (CD). The aim of this study was to investigate the effect of helicobacter pylori (H.pylori) infection eradication on serum level of tTG in children with CD.MethodsThis study was conducted on children aged 2 to 18 who referred to reference hospitals for diagnosis of CD. After upper endoscopy and biopsy to confirm CD and H.pylori infection, the children were divided into three groups (including group one: 16 CD patients with positive H. pylori; group two: 16 non-CD patients with positive H. pylori; and group three: 56 CD patients with negative H. pylori), respectively. The tTG level in study groups were compared after the eradication of H.pylori.ResultsThe mean age of the subjects in the group one, two, and three was 9.7 ± 3.33, 11.8 ± 3.14, and 7.6 ± 3.32 years, respectively. Our results showed that in group one, mean tTG increased after eradication of H.pylori infection, however, these changes were not significant (182.43 vs. 157.18, P = 0.121). In the second group, although unlike the first group, mean tTG decreased after eradication of the infection, but still these changes were not significant (9.56 vs. 22.18, P = 0.449). Furthermore, at the baseline level, the mean tTG in the group three was closer to the mean tTG in the first group.ConclusionOur findings showed that the eradication of H.pylori infection does not have a significant effect on tTG levels in children with and without CD.

Comparison of transglutaminase and l‐ascorbic acid additives in improving the quality of bread made from sunn pest (Eurygaster integriceps) damaged wheat

SummarySunn pest (SP) is one of the most detrimental wheat bugs in Asia and Europe. Flour milled from SP damaged wheats (SPDW) exhibits weak dough characteristics and unsatisfactory baking quality due to its high protease content. l‐ascorbic acid (l‐AA) and transglutaminase (TG) are the two different bread additives that lead to protein polymerisation via different mechanisms. This study aimed to compare the independent and combined effects of TG and l‐AA additives in improving quality of bread made from SPDW. Compared to l‐AA, TG is an additive that is much more effective for strengthening the dough. The positive effect of l‐AA was more clearly found in flours with low‐level of SPDW (LLSPDW). Bread structure and properties of LLSPDW could be restored by addition of suitable‐levels of l‐AA (75–100 mg/kg) and/or low‐level of TG (0.3%). High‐level of SPDW (HLSPDW) could be restored only by addition of suitable level of TG (≥1%). In bread‐making with HLSPDW flours, TG can be successfully used to maintain dough stability and bread attributes, however, the positive effect of l‐AA remained at very limited levels and cannot compare with the contribution of TG. The results of this study can be utilised to improve the quality of breads made with SPDW flours.

Are children with attention-deficit/ hyperactivity disorder (ADHD) more likely to develop celiac disease? A prospective study.

The aim of this study was to evaluate whether the prevalence of celiac among attention-deficit/hyperactivity disorder (ADHD) patients is higher than among the normal population. The present study was a prospective one investigating ADHD children referred to the Neurology Clinic and Pediatric Ward at Amir Al-Momenin Hospital of Zabol (Sistan and Baluchestan, Iran) in 2019 after their parents' signing of a consent form. All patients underwent Biocard™ Celiac and serology tests. Data were analyzed with SPSS version 21 software. Of all 76 ADHD children undergoing a serum IgA antibodies concentration test, 58 (76%) were male and 18 (23.7%) were female. The mean age of the children was 6.9 ± 2.4, ranging from 2 years to 12 years. The diagnosis of IgA immunodeficiency was rejected for all children based on total serum IgA antibody results. The overall mean anti-tissue transglutaminase (TTG) level was 6.8 ± 5.3 U/ml, ranging from 0.2 to 37 U/ml. There was no significant difference regarding TTG levels between boys and girls (5.1 vs. 6.0) U/ml. Based on the anti-TTG level results, no celiac case was found among the ADHD patients. There is as yet no evidence suggesting a link between celiac disease and ADHD. Thus, routine celiac disease screening when evaluating for ADHD (and is not recommended). However, the possibility of untreated celiac disease predisposing an individual to ADHD-like behaviors should be considered. Hence, physicians are recommended to evaluate a broad range of physical symptoms, in addition to typical neuropsychiatric symptoms, when evaluating ADHD patients.

The moisturizing effect of Capparis spinosa fruit extract targeting filaggrin synthesis and degradation.

Small molecular natural products, such as betaine, have unique moisturizing advantages. Capparis spinosa L. fruit is rich in quaternary ammonium alkaloids such as betaine and stachydrine. However, few studies investigated its efficacy and mechanism on human skin. Polysaccharides-free C. spinosa fruit extract (CS) was obtained to study its moisturizing effect and mechanisms focusing on filaggrin (FLG) synthesis and degradation. The clinical moisturizing test was carried out on human arms, calves, and faces after CS treatment for 0.5-6h. The change in the level of FLG, caspase 14, loricrin, and transglutaminase 5 (TGM 5) was measured by immunofluorescence after CS treatment for 4 and 24 h in a reconstructed epidermis model. Also, the content of pyrrolidone carboxylic acid (PCA) in the stratum corneum was tested by high-performance liquid chromatography (HPLC) both in the epidermis model and human calves. Compared with glycerin (positive control), 5% CS showed a strong skin hydration effect on arms and calves when applied for 0.5-6h. Also, the face hydration increased at 0.5 and 4 h. In addition, 3% CS applied to the recombinant epidermis model under low humidity promoted the immunodetected levels of caspase 14 and PCA content but reduced the levels of FLG at 4h, however, the levels of FLG, loricrin, and TGM 5 were promoted at 24 h. Meanwhile, CS treatment for 4h in human calves increased the PCA content in the stratum corneum by 29.9%. Topical application of CS on human skin showed an instant and long-lasting increase in skin hydration by regulating the FLG network. It promoted FLG degradation to form PCA at 4h both in vivo and in vitro, increasing FLG synthesis after 24 h, potentially reforming the FLG monomer reservoir to alleviate the skin's dry condition.

Deep Association between Transglutaminase 1 and Tissue Eosinophil Infiltration Leading to Nasal Polyp Formation and/or Maintenance with Fibrin Polymerization in Chronic Rhinosinusitis with Nasal Polyps.

Transglutaminase (TGM) isoform catalyze the cross-linking reaction of identical or different substrate proteins. Eosinophil has been recognized in chronic rhinosinusitis with nasal polyps (CRSwNP) forming tissue eosinophil in nasal polyp (NP), and TGM isoforms are suggested to be associated with a critical role in asthma and other allergic conditions. The aim of this study was to reveal the association of specific TGM isoform with both the tissue eosinophil infiltration deeply concerning with the intractable severity of CRSwNP and the fibrin polymerization ability of TGM isoform associated with the tissue eosinophil infiltration, which lead to NP formation and/or maintenance in CRSwNP. NP tissues (CRSwNP group) and uncinate process (UP) (control group) were collected from patients with CRSwNP and control subjects. We examined: (1) the expression level of TGM isoforms by using a real-time polymerase chain reaction (PCR) and the comparison to the issue eosinophil count in the CRSwNP group, (2) the location of specific TGM isoform in the mucosal tissue using immunohistochemistry, (3) the inflammatory cell showing the colocalization of specific TGM isoform in Laser Scanning Confocal Microscopy (LSCM) imaging, and (4) the fibrin polymerase activity of specific TGM isoform using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). A certain level of TGM 1, 2, 3, 5 expression was present in both the CRSwNP group and the control group. Only TGM 1 expression showed a positive significant correlation with the tissue eosinophil count in the CRSwNP group. The localization of TGM 1 in NP (CRSwNP) laid mainly in a submucosal layer as inflammatory cells and was at the cytoplasm in the tissue eosinophil. Fibrin polymerase activity of TGM 1 showed the same polymerase ability of factor XIIIA. TGM 1 might influence the NP formation and/or maintenance in CRSwNP related to the tissue eosinophil infiltration, which formed fibrin mesh composing NP stroma.

Urinary levels of pro-fibrotic transglutaminase 2 (TG2) may help predict progression of chronic kidney disease.

Renal clinical chemistry only detects kidney dysfunction after considerable damage has occurred and is imperfect in predicting long term outcomes. Consequently, more sensitive markers of early damage and better predictors of progression are being urgently sought, to better support clinical decisions and support shorter clinical trials. Transglutaminase 2 (TG2) is strongly implicated in the fibrotic remodeling that drives chronic kidney disease (CKD). We hypothesized that urinary TG2 and its ε-(γ-glutamyl)-lysine crosslink product could be useful biomarkers of kidney fibrosis and progression. Animal models: a rat 4-month 5/6th subtotal nephrectomy model of CKD and a rat 8-month streptozotocin model of diabetic kidney disease had 24-hour collection of urine, made using a metabolic cage, at regular periods throughout disease development. Patients: Urine samples from patients with CKD (n = 290) and healthy volunteers (n = 33) were collected prospectively, and progression tracked for 3 years. An estimated glomerular filtration rate (eGFR) loss of 2–5 mL/min/year was considered progressive, with rapid progression defined as > 5 mL/min/year. Assays: TG2 was measured in human and rat urine samples by enzyme-linked immunosorbent assay (ELISA) and ε-(γ-glutamyl)-lysine by exhaustive proteolytic digestion and amino acid analysis. Urinary TG2 and ε-(γ-glutamyl)-lysine increased with the development of fibrosis in both animal model systems. Urinary TG2 was 41-fold higher in patients with CKD than HVs, with levels elevated 17-fold by CKD stage 2. The urinary TG2:creatinine ratio (UTCR) was 9 ng/mmol in HV compared with 114 ng/mmol in non-progressive CKD, 1244 ng/mmol in progressive CKD and 1898 ng/mmol in rapidly progressive CKD. Both urinary TG2 and ε-(γ-glutamyl)-lysine were significantly associated with speed of progression in univariate logistic regression models. In a multivariate model adjusted for urinary TG2, ε-(γ-glutamyl)-lysine, age, sex, urinary albumin:creatinine ratio (UACR), urinary protein:creatinine ratio (UPCR), and CKD stage, only TG2 remained statistically significant. Receiver operating characteristic (ROC) curve analysis determined an 86.4% accuracy of prediction of progression for UTCR compared with 73.5% for UACR. Urinary TG2 and ε-(γ-glutamyl)-lysine are increased in CKD. In this pilot investigation, UTCR was a better predictor of progression in patients with CKD than UACR. Larger studies are now warranted to fully evaluate UTCR value in predicting patient outcomes.

Transitional elevation of anti-tissue transglutaminase antibodies in children with type 1 diabetes mellitus without coeliac disease

The frequent association of type 1 diabetes mellitus with coeliac disease is well known. Development of transitional elevation of anti-tissue transglutaminase antibodies in the diagnosis of type 1 diabetes is reported in some studies. In these cases, the anti-tissue transglutaminase antibodies returned to normal without gluten-free diet. Our aim was to assess the frequency of transitional elevation of anti-tissue transglutaminase in our type 1 diabetes patients. We aimed to investigate the prevalence of coeliac disease in patients with type 1 diabetes. Patients with type 1 diabetes at the Ist Department of Paediatrics, Semmelweis University, were enrolled in the study (238 girls, 265 boys; the median age at the time of type 1 diabetes diagnosis was 7.83 [4.67-11] years). Descriptive statistical analysis was done and the time of appearance, extent, frequency and type of elevated anti-tissue transglutaminase antibodies were examined. The proportion of children with diagnosed coeliac disease was 12.52%. We detected transitional anti-tissue transglutaminase elevation in 48 cases (10.9%). Temporarily elevated antibody levels were measured 71 times. In 34 children (70.83%), the temporary elevation occured once, while in the others, antibody levels became positive 2-8 times. The elevation of the IgA antibody was more frequent than the elevation of the IgG antibody (54 vs. 5). The frequency of temporary elevated anti-tissue transglutaminase levels is considered high. Our study confirms the recommendation that in the case of moderate anti-tissue transglutaminase levels with lack of clinical symptoms, control antibody measurement is necessary with ongoing gluten consumption. Orv Hetil. 2021; 162(48): 1924-1930.

Evaluation of serum long non-coding RNA (Gas5) level and keratinocyte transglutaminase 1 (TGM1) activity as novel biomarkers in psoriasis patients

BackgroundPsoriasis is considered an autoimmune disease, ecological and genetic factors together function a vital role in the cause, long non-coding RNA (lncRNAs) perform a regulatory key for the expression of an inflammatory gene by cooperating with the transcription factors. Keratinocyte transglutaminase enzymes are calcium-dependent serve enzymes that stimulate the progress of the cornified cell envelope, which characterize the epidermal keratinocytes that have subjected the ending of segregation. This study aimed to investigate the expression level of long non-coding RNA (GAS5) and keratinocyte transglutaminase 1 (TGM1) activity in psoriatic patients and its possible role in psoriasis pathogenesis. Subjects and methodsThis survey implicated thirty patients with chronic plaque psoriasis, 30 sex, and age-matched healthy controls. GAS5 was measured using quantitative PCR (qPCR). Keratinocyte transglutaminase 1 (TGM1) activity was detected by using the ELISA technique. ResultsThe serum level of long non-coding RNA (GAS5) values were significantly lower between patients with psoriasis in comparison to normal control and the serum levels of keratinocyte transglutaminase 1 (TGM1) values were significantly high between patients with psoriasis in comparison to normal control.

Effects of microbial transglutaminase levels on donkey cheese production.

Microbial transglutaminase (MTGase) is an enzyme widely used in the dairy sector to improve the functional properties of protein-based products via the formation of a network between protein molecules. The aim of this study involving cheese from the milk of donkeys was to evaluate the effects of treatment with MTGase at the concentrations of 0 (control), 5, 8 and 10 U/g milk protein on the cheese-making process parameters, as well as the physical and chemical characteristics of the resulting cheese. MTGase influenced the time of gel formation from rennet addition (P < 0.05), with a delay at the two highest concentrations, accompanied by a lower (P < 0.01) pH of cheese and the lowest (P < 0.01) loss in cheese weight at 24 h of storage. The highest gel viscosity (P < 0.01) was observed at the highest concentration of the enzyme, reaching the value of 70 mPa⋅sec after 60 min. The chemical composition and color of the cheeses were not significantly affected by the inclusion of MTGase, regardless of the enzyme concentration. These findings may be of relevance in adapting the cheese-making process and might help in the design of new dairy products from donkey's milk.