Modulatory Effect of Natural Antioxidants on Tissue Transglutaminase Levels in Olfactory Ensheathing Cells Exposed to Amyloid-β: Integrated Biochemical and Computational Analysis.
This study combines molecular modeling and biological experiments to evaluate four natural antioxidants' effects on tissue transglutaminase levels in olfactory ensheathing cells exposed to amyloid-β. Results show berberine and curcumin counteract Aβ-induced TG2 upregulation, restore cell viability, reduce oxidative stress, and prevent apoptosis, suggesting their potential as neuroprotective agents for neurodegenerative diseases like Alzheimer's.
Herein, we adopted a dual approach combining molecular modeling and biological studies, in order to assess the interaction between four selected natural antioxidants (NAs; berberine, curcumin, astaxanthin, indicaxanthin) and tissue transglutaminase (TG2) levels both in the absence and in the presence of full native peptide of amyloid-β (Aβ). Docking studies were performed to ascertain the binding affinity of NAs against the TG2 closed, Ca2+-bound closed, and open forms. In the biological investigation, the effect of berberine and curcumin treatment on TG2 in Olfactory Ensheathing Cells (OECs) exposed to Aβ(1-42) or to Aβ(25-35), a Aβ toxic fragment, or to reverse-sequence fragment Aβ(35-25), an Aβ not toxic fragment, was tested. In addition, their effect on the percentage of cell viability and cytoskeleton marker (GFAP, vimentin and nestin) levels were evaluated. The role of berberine and curcumin on both endocellular levels of reactive oxygen species (ROS) and apoptotic pathway activation were also assessed. Our findings demonstrate that pretreatment of OECs with these NAs counteracted the Aβ-induced upregulation of TG2, restoring its expression to control levels and preserving its predominant cytosolic localization. Furthermore, antioxidant pretreatment reinstated cell viability, normalized the expression of GFAP, vimentin, and nestin, reduced intracellular ROS accumulation, and prevented activation of the apoptotic cascade. Our findings demonstrate that integrating computational and biological approaches, enhances the identification of potent therapeutic agents and also highlights berberine and curcumin as promising candidates for the development of novel neuroprotective drugs against neurodegenerative disorders, including Alzheimer's disease.
- Abstract
1
- 10.1016/j.ajog.2012.10.317
- Dec 27, 2012
- American Journal of Obstetrics and Gynecology
152: Physical exam indicated cerclage versus expectant management: a systematic review and metaanalysis
- Research Article
9
- 10.3390/antiox12030750
- Mar 19, 2023
- Antioxidants
Astaxanthin, a natural compound of Haematococcus pluvialis, possesses antioxidant, anti-inflammatory, anti-tumor and immunomodulatory activities. It also represents a potential therapeutic in Alzheimer's disease (AD), that is related to oxidative stress and agglomeration of proteins such as amyloid-beta (Aβ). Aβ is a neurotoxic protein and a substrate of tissue transglutaminase (TG2), an ubiquitary protein involved in AD. Herein, the effect of astaxanthin pretreatment on olfactory ensheathing cells (OECs) exposed to Aβ(1-42) or by Aβ(25-35) or Aβ(35-25), and on TG2 expression were assessed. Vimentin, GFAP, nestin, cyclin D1 and caspase-3 were evaluated. ROS levels and the percentage of cell viability were also detected. In parallel, delayed luminescence (DL) was used to monitor mitochondrial status. ASTA reduced TG2, GFAP and vimentin overexpression, inhibiting cyclin D1 levels and apoptotic pathway activation which induced an increase in the nestin levels. In addition, significant changes in DL intensities were particularly observed in OECs exposed to Aβ toxic fragment (25-35), that completely disappear when OECs were pre-incubated in astaxantin. Therefore, we suggest that ASTA pre-treatment might represent an innovative mechanism to contrast TG2 overexpression in AD.
- Research Article
170
- 10.1046/j.1471-4159.1999.02018.x
- Nov 1, 1999
- Journal of Neurochemistry
The polyglutamine-expanded N-terminal region of mutant huntingtin causes neurodegeneration in Huntington's disease (HD). Neuronal intranuclear and cytosolic inclusions composed of mutant huntingtin are found in brains of HD patients. Because tissue transglutaminase cross-links proteins into filamentous aggregates and polypeptide-bound glutamines are primary determining factors for tissue transglutaminase-catalyzed reactions, it has been hypothesized that tissue transglutaminase may contribute to the formation of these aggregates. In this report immunohistochemical and biochemical methods were used to demonstrate that tissue transglutaminase expression and transglutaminase activity are elevated in HD brains in a grade-dependent manner. In the striatum, tissue transglutaminase activity was significantly increased in the grade 3 HD cases compared with controls. When normalized to the neuronal marker calbindin D28k, immunoblot analysis revealed that in the striatum the levels of tissue transglutaminase were significantly increased in all HD cases compared with controls. Immunohistochemical staining of the HD striatum revealed that tissue transglutaminase immunoreactivity was markedly increased in all grades as compared with controls. In the superior frontal cortex, tissue transglutaminase activity was significantly higher in all HD cases as compared with controls. Quantitative analysis of immunoblots demonstrated that tissue transglutaminase levels were elevated in HD grades 2 and 3 cases. Tissue transglutaminase immunoreactivity within the superior frontal neocortex was also greater in all the HD cases compared with controls. These data clearly indicate that tissue transglutaminase is elevated in HD brain and may play a role in the disease process.
- Research Article
121
- 10.1016/j.cgh.2007.01.003
- Apr 11, 2007
- Clinical Gastroenterology and Hepatology
Correlation of Duodenal Histology With Tissue Transglutaminase and Endomysial Antibody Levels in Pediatric Celiac Disease
- Research Article
12
- 10.1097/mpg.0000000000003130
- Mar 17, 2021
- Journal of pediatric gastroenterology and nutrition
Celiac disease (CD) is a common intestinal autoimmune disorder with diverse presenting features. We aimed to determine age-dependent patterns in CD presentation, diagnosis and management at a large tertiary referral center. A retrospective review of electronic medical records of pediatric patients diagnosed with CD between January 1999 and December 2018 at Schneider Children's Medical Center of Israel. We compared demographics, clinical and laboratory parameters between four age groups at CD presentation. A cohort of 932 children was divided into four groups by age (in years) at diagnosis: 0-3 (17.9%), 3-6 (31.8%), 6-12 (34.5%), 12-18 (15.8%). The youngest age group presented more frequently with diarrhea, weight loss, abdominal distention, vomiting and lower weight z scores, P < 0.01. Hypoalbuminemia and zinc deficiency were also more frequent in this age group, compared to older patients (P < 0.05, each). Rates of anemia were higher in younger age groups (0-3 and 3-6 years), compared to older age groups, P < 0.05. Patients in the younger age groups (0-3 and 3-6 years) presented more frequently with tissue transglutaminase (TTG) levels above 10 times the upper limit of normal (ULN; P < 0.05), and more often normalized their CD serologies by 24 months of gluten-free diets (GFD) compared to older age groups (P < 0.05). There is an age-dependent variation in CD presentation during childhood. Younger patients present more often with malabsorptive features, and higher TTG levels, yet normalize TTG while on GFD more rapidly than older patients. Clinicians should be aware of the diversity in CD presentation and course at the various presentation age.
- Research Article
1
- 10.1097/01.mpg.0000181857.91264.f6
- Oct 1, 2005
- Journal of Pediatric Gastroenterology and Nutrition
Background: Although IgA endomysial antibodies (EMA) and tissue transglutaminase (TG) are sensitive and specific serologic tests for the diagnosis of celiac disease, there is limited information on the association of the magnitude of antibody level with the severity of the histological abnormalities of the intestine. Purpose: To determine if EMA and TG titers correlate with the severity of histological changes in patients with celiac disease. Methods: We identified 148 children from our laboratory database that had EMA, TG and intestinal biopsies performed. IgA EMA was determined by indirect immunofluorescence with results expressed as a dilutional titer with positivity determined at 1:5. IgA TG was determined by an enzyme linked human immunosorbent ELISA assay with results expressed in standardized units. A modified Marsh histological grading system was used to describe the duodenal biopsies: Type 0 normal, I increased intraepithelial lymphocytes (IEL), II hyperplastic crypts, IIIa partial villus atrophy, IIIb subtotal villus atrophy, IIIc total villous atrophy. Results: Mean values for EMA (Table 1) and TG (Table 2) progressively increased with increasing Marsh score.TABLE 1: Endomysial antibody titer and Marsh GradeTABLE 2: Tissue transglutaminase level and Marsh GradeConclusion: There was considerable variability in EMA and TG levels for each Marsh grade, so that an individual level could not be utilized to predict histological severity. The data show that as a group, increasing severity of the histological lesion in celiac disease was associated with increased levels of both IgA EMA and TG antibodies.
- Research Article
6
- 10.1136/archdischild-2021-323250
- Feb 28, 2022
- Archives of Disease in Childhood
BackgroundCoeliac disease (CD) is common. Response to a gluten-free diet is assessed through serial measurement of tissue transglutaminase (TTG) antibody titre. However, the relationship of TTG titres to symptoms and...
- Research Article
33
- 10.1016/s0306-4522(02)00482-7
- Nov 9, 2002
- Neuroscience
NMDA-evoked excitotoxicity increases tissue transglutaminase in cerebellar granule cells
- Research Article
3
- 10.3390/ijms242316915
- Nov 29, 2023
- International Journal of Molecular Sciences
Nowadays, there is considerable attention toward the use of food waste from food processing as possible sources of compounds with health properties, such as anticancer activity. An example is tomato processing, which is responsible for generating a remarkable amount of waste (leaves, peel, seeds). Therefore, our goal was to evaluate the potential anticancer property of tomato extracts, in particular “Datterino” tomato (DT) and “Piccadilly” tomato (PT), and to study their phytochemical composition. Liquid chromatography with tandem mass spectrometry (LC/MS-MS) results showed that these extracts are rich in alkaloids, flavonoids, fatty acids, lipids, and terpenes. Furthermore, their potential anticancer activity was evaluated in vitro by MTT assay. In particular, the percentage of cell viability was assessed in olfactory ensheathing cells (OECs), a particular glial cell type of the olfactory system, and in SH-SY5Y, a neuroblastoma cell line. All extracts (aqueous and ethanolic) did not lead to any significant change in the percentage of cell viability on OECs when compared with the control. Instead, in SH-SY5Y we observed a significant decrease in the percentage of cell viability, confirming their potential anticancer activity; this was more evident for the ethanolic extracts. In conclusion, tomato leaves extracts could be regarded as a valuable source of bioactive compounds, suitable for various applications in the food, nutraceutical, and pharmaceutical fields.
- Research Article
10
- 10.3390/ijms22073388
- Mar 25, 2021
- International Journal of Molecular Sciences
Herein, we assessed the effect of full native peptide of amyloid-beta (Aβ) (1-42) and its fragments (25-35 and 35-25) on tissue transglutaminase (TG2) and its isoforms (TG2-Long and TG2-Short) expression levels on olfactory ensheathing cells (OECs). Vimentin and glial fibrillary acid protein (GFAP) were also studied. The effect of the pre-treatment with indicaxanthin from Opuntia ficus-indica fruit on TG2 expression levels and its isoforms, cell viability, total reactive oxygen species (ROS), superoxide anion (O2−), and apoptotic pathway activation was assessed. The levels of Nestin and cyclin D1 were also evaluated. Our findings highlight that OECs exposure to Aβ(1-42) and its fragments induced an increase in TG2 expression levels and a different expression pattern of its isoforms. Indicaxanthin pre-treatment reduced TG2 overexpression, modulating the expression of TG2 isoforms. It reduced total ROS and O2− production, GFAP and Vimentin levels, inhibiting apoptotic pathway activation. It also induced an increase in the Nestin and cyclin D1 expression levels. Our data demonstrated that indicaxanthin pre-treatment stimulated OECs self-renewal through the reparative activity played by TG2. They also suggest that Aβ might modify TG2 conformation in OECs and that indicaxanthin pre-treatment might modulate TG2 conformation, stimulating neural regeneration in Alzheimer’s disease.
- Research Article
2
- 10.1096/fasebj.20.5.a1145-c
- Mar 1, 2006
- The FASEB Journal
Berberine, a yellow benzylisoquinoline alkaloid, is one of the constituent of Coptis Chines, and is commonly used in Chinese herbal medicine for patients with gastrointestinal disorders. The pharmacological effects of berberine include anti-inflammation, antidiarrhetic and antimalarial activities, even containing antimicrobial activity. However, its mechanism of action on cell migration of human gastric cancer SNU-5 is not fully understood. At first, we examined the effects of berberine on the percentage of viable cells and also found that berberine induced dose-dependent apoptosis in human gastric cancer SNU-5 cells. Next, we examined the effect of berberine on the levels of reactive oxygen species and matrix metalloproteinase-1, -2, -7 and -9 by Western blotting and the results showed that berberine induced ROS for up to 6 hour incubation before starting to decrease the ROS production and we also found out that berberine induced down-regulation of MMP-1 -2, and -9 but it did not affect the levels of MMP-7. We also used polymerase chain reaction to examine the mRNA levels of MMPs from SNU-5 cells after treated with berberine for 24 hours and the results show that berberine inhibited the gene expression of MMP-1, -2 and -9 in human SNU-5 cells but it did not affect MMP-7. Those effects are dose-dependent manner.
- Research Article
79
- 10.1016/j.cgh.2020.03.038
- Mar 23, 2020
- Clinical Gastroenterology and Hepatology
Real-World Gluten Exposure in Patients With Celiac Disease on Gluten-Free Diets, Determined From Gliadin Immunogenic Peptides in Urine and Fecal Samples
- Research Article
15
- 10.5455/apr.112220111551
- Jan 1, 2012
- Annals of Paediatric Rheumatology
Several studies have indicated that adult patients with spondyloarthritis (SpA) have elevated levels of antibodies associated with celiac disease (CD). This has not been studied in children, and none of the studies corrected for total IgA levels. We measured total IgA and IgA against tissue transglutaminase (TTG) levels in 42 children with Juvenile Idiopathic Arthritis (JIA), of whom 11 had SpA, along with 10 non-inflammatory control subjects. Median (IQR) TTG IgA levels were elevated among children with ERA (8.8, 4.6 - 21) compared to 'JIA controls' (JIA subgroups other than ERA) (2.8, 1.5 - 5.9) and a healthy non-inflammatory control group (1.5, 0.82 - 12), p = 0.017, Kruskal-Wallis. There was no correlation between TTG IgA levels and measures of disease activity or with medicine use. None of the children were diagnosed endoscopically with celiac disease. Patients with ERA likewise had elevated total IgA level compared to the other groups (p = 0.001), and total IgA levels correlated highly with TTG IgA (r = 0.599, p<0.001). These findings suggest that elevations in TTG IgA may reflect increased polyclonal IgA production, rather than a specific intestinal inflammatory process.
- Research Article
5
- 10.1080/14397595.2016.1270497
- Feb 21, 2017
- Modern Rheumatology
We aimed to assess the frequency of celiac disease (CD) in patients with Familial Mediterranean Fever (FMF). This prospective study was carried out from October 2015 to March 2016 and included 303 patients with FMF. We used 98 sex- and age-matched healthy subjects as a control group. Levels of total IgA and tissue transglutaminase (tTG) IgA antibody were measured in all groups. Those with increased level of tTG IgA were tested for anti-endomysium IgA antibodies (EMA). Patients with positive EMA underwent gastro-duodenoscopy and intestinal biopsy for a definite diagnosis of CD. Only 9 of 303 patients (2.9%) were positive for tTG IgA. Patients positive for tTG IgA were then tested for EMA and only one of them (0.3%) had a positive result. This patient underwent gastro-duodenoscopy. The pathological report was compatible with Marsh 0 classification score for the diagnosis of CD. Two subjects from the control group were positive for tTG IgA but none of them had positive EMA antibodies. We did not find CD in the large cohort of childhood FMF patients. The prevalence of CD did not show association with presence of childhood FMF in this study and CD would not be a considerable complication of childhood FMF.
- Research Article
- 10.1590/s0004-2803.201800000-31
- Jun 1, 2018
- Arquivos de Gastroenterologia
Familial Mediterranean fever and celiac disease share some common clinical features such as abdominal pain, diarrhea, arthralgia and arthritis. Also, both of the diseases are associated with many inflammatory and autoimmune diseases. Previous studies have shown the association between familial Mediterranean fever (FMF) and different clinical conditions. We aimed to investigate the relationship between celiac disease and colchicine-resistant familial Mediterranean fever (crFMF) disease. This prospective study was conducted at the Department of Pediatric Gastroenterology and Pediatric Rheumatology from October 2015 to August 2016. A total of 24 patients with crFMF were included in the study. We used 60 sex- and age-matched healthy subjects as a control group. Levels of total IgA and tissue transglutaminase (tTG) IgA antibody were measured in both groups. Those with increased level of tTG IgA were tested for anti-endomysium IgA antibodies (EMA). Gastroduodenoscopy and intestinal biopsy were planned for a definite diagnosis of celiac disease in patients with positive EMA. Of the 24 patients in this study, 18 (75.0%) were female. Only 4 (16.6%) of 24 patients were positive for tTG IgA. Patients with positive tTG IgA were then tested for EMA IgA antibodies and none of them had a positive result. Only one (1.6%) subject from the control group was positive for tTG IgA but EMA positivity was not detected. We did not found celiac disease in 24 children with crFMF. Since crFMF disease is rarely seen in general population, further studies with more patients are needed to provide more precise interpretation.