Evaluation of protein undernourishment on the condylar process of the Wistar rat mandible correlation with insulin receptor expression

The mandible condylar process cartilage (CP) of Wistar rats is a secondary cartilage and acts as a mandibular growth site. This phenomenon depends on adequate proteins intake and hormone actions, including insulin. Objectives The present study evaluated the morphological aspects and the expression of the insulin receptor (IR) in the cartilage of the condylar process (CP) of rats subjected to protein undernourishment. Material and Methods The nourished group received a 20% casein diet, while the undernourished group (U) received a 5% casein diet. The re-nourished groups, R and RR, were used to assess the effects of re-nutrition during puberty and adulthood, respectively. CPs were processed and stained with picro-sirius red, safranin-O and azocarmine. Scanning electron microscopy and immunohistochemistry were also performed. Results The area of the CP cartilage and the number of cells in the chondroblastic layer decreased in the U group, as did the thickness of the CP layer in the joint and hypertrophic layer. Renourishment during the pubertal stage, but not during the adult phase, restored these parameters. The cell number was restored when re-nutrition occurred in the pubertal stage, but not in the adult phase. The extracellular matrix also decreased in the U group, but was restored by re-nutrition during the pubertal stage and further increased in the adult phase. IR expression was observed in all CPs, being higher in the chondroblastic and hypertrophic cartilage layers. The lowest expression was found in the U and RR groups. Conclusions Protein malnutrition altered the cellularity, the area, and the fibrous cartilage complex, as well as the expression of the IRs. .

Transforming growth factor-β-1 polymorphisms are infrequent but exist at selected loci in oral submucous fibrosis.

Background : Oral submucous fibrosis (OSF) may be considered a collagen metabolic disorder resulting from areca-nut alkaloid exposure and individual variation in collagen metabolism. Due to the complexity of OSF pathogenesis, it is important to elucidate independent and interactive effects of polymorphisms of collagen-related genes on OSF risk. Materials and Methods : This study is focused on seven polymorphisms (SNPs) of transforming growth factor-beta-1 (TGF-beta-1) gene in patients with oral submucous fibrosis (OSF), belonging to south Indian ethnic extraction. The mean age at presentation was 43.9 years, range 23-72 years (n=50, M:F ratio, 2.6:1). DNA samples from 50 subjects of the same ethnic group and comparable demographic features who have had practiced the habit of areca-chewing of almost equal duration, but remained free of disease constituted the controls. All DNA samples were collected progressively and purified from peripheral blood employing standard protocols and tested for SNPs. They included two polymorphisms in the promoter region (C-509T and G-800A), three polymorphisms in exon-1 (Arg25Pro(G915C), Leu10Pro(T869C), Glu47Gly(A979G) and two in 5 ͲUTR regions (C→T(rs13306708) and G→A (rs9282871). The extracted DNA samples along with the primers underwent PCR amplification and the genotypic and allelic frequencies were calculated. All calculations were performed using the SPSS software. The PCR products were purified and subsequently sequenced using Flour S™ multi-imager system (Biorad). The sequenced data were analyzed using the BioEdit sequence analysis software. Results : Out of the seven polymorphisms analyzed, six such as two in the promoter region, three in exon-1 and one in 5¢UTR were found to have a " P" value above 0.05 and hence were not significant. The C→T transition (rs13306708) in the 5¢UTR region recorded a " P" value of 0.03 on comparison and hence was found to be significant. The allelic frequencies for this C→T transition in patients were 68.7% C and 31.2% T (27CC, 15CT, 8TT) and that in controls were 89.5% C and 10.4% T (42CC, 6CT, 2TT). Conclusions : The polymorphism in 5¢UTR C-T in TGF beta 1 gene has a significant association with OSF, being a prime determinant in the pro-angiogenic pathway which has got direct bearing with the pathophysiology of the disease. The proximity of this polymorphism to the transcription site and the associated risk involved is discussed.

Association of Leu125Val polymorphism of platelet endothelial cell adhesion molecule-1 (PECAM-1) gene & soluble level of PECAM-1 with coronary artery disease in Asian Indians.

BACKGROUND & OBJECTIVES: Platelet endothelial cell adhesion molecule-1 (PECAM-1) plays a key role in the transendothelial migration of circulating leukocytes (diapedesis) during vascular inflammation. We hypothesized that genetic variation and the level of soluble PECAM-1 could be associated with the development of atherosclerosis and conducted a study on gene polymorphisms of PECAM-1 and soluble PECAM-1 levels in Asian Indian patients with coronary artery disease (CAD) in Singapore. METHODS: Of the 137 angiographically confirmed patients (> or =70% stenosis) of CAD and 110 controls in Asian Indian population, two single nucleotide polymorphisms (SNPs) of PECAM-1 gene, C+373G (Leu125Val) at exon 3 and G+1688A (Ser563Asn) at exon 8 were analyzed by polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) strategy. In addition, plasma soluble PECAM-1, P-selection and lipid profile were measured. Chi- square test and student t test were adopted to compare categorical and continuous variables, respectively. RESULTS: A significant decrease in C allele frequency but increase in G allele frequency of the Leu125Val (C/G) polymorphism were observed in CAD patients as compared with controls (0.54/0.46 vs 0.663/0.337 respectively, P=0.008). Alteration in genotype distributions (CC, CG and GG) of the Leu125Val polymorphism between CAD patients and controls (P=0.009) was also significant. A similar trend was observed on the allele frequencies (G/A) and genotype distributions of Ser563Asn (G/A) polymorphism, though the difference did not reach significance. On the other hand, plasma level of soluble PECAM-1 (sPECAM-1) was markedly elevated in CAD patients (P=0.006), and associated with soluble P-selectin and lipid profiles. INTERPRETATION & CONCLUSION: Our study showed that Leu125Val polymorphism of PECAM-1 gene and elevated soluble PECAM-1 were related to severe coronary artery stenosis in CAD patients of Asian Indian origin in Singapore. Our data also suggest that PECAM-1 plays an important role in the development of atherosclerosis.

Effects of Val34Leu and Val35Leu polymorphism on the enzyme activity of the coagulation factor XIII-A

Change in fibrin stabilizing activity of factor XIII A subunit (FXIII-A) caused by a specific mutation, Val34Leu, is recently implicated to incidences of pathophysiology of thrombosis. In an effort to understand the effect of Val34Leu on enhanced catalytic role of FXIII-A, wild type human factor XIII A (HFXIII-A) and mutant HFXIII-A: HFXIII-A (V34L), HFXIII-A (V35L) and HFXIII-A (V34L/V35L) cDNA were expressed in E.coli system where the purified recombinant FXIII-A (rFXIII-A) showed a similar specific transglutaminase activity comparable to the human native FXIII-A from platelet. Using these rFXIII-A mutants, the activation kinetics by thrombin and the enzymatic properties of the activated rFXIII-A were characterized. rFXIII-A (V34L) and rFXIII-A (V34L/V35L) mutants were activated by thrombin much faster than those of wild type rFXIII-A and V35L variant. However, the activated rFXIII-A and mutants showed the identical catalytic efficiency as measured by in vitro assay. These results suggest that ready activation caused by a specific mutation of neighboring thrombin cleavage site(s) in the activation peptide of FXIII-A like V34L resulted in the real-time amount of the activated factor XIII-A that could influence the outcome of fibrin stabilization in vivo such as alpha2- plasmin inhibitor crosslinking to fibrin, a reaction known to be dependent on the initial concentration of active factor-XIII-A.

No Association of Factor XIII Val34Leu Polymorphism with Primary Intracerebral Hemorrhage and Healthy Controls in Korean Population

The polymorphism in the factor XIII A-subunit gene (FXIII Val34Leu) has been recognized as a risk factor for primary intracerebral hemorrhage (PICH). In addition, FXIII Val34Leu has a significant ethnic heterogeneity. FXIII Val34Leu was detected in 41.7-54.8% of the Westerners, but in 2.5% of the Asians. We aimed to evaluate the prevalence of FXIII Val34Leu in patients with PICH and in healthy controls among Koreans. We recruited 58 in-patients with PICH, defined by brain computed tomography or magnetic resonance imaging, and 48 controls matched for age, sex, and risk factors for cerebrovascular diseases. Genomic DNA was extracted from blood. A 183-bp fragment of exon 2/intron B of the factor XIII Asubunit gene was amplified by polymerase chain reaction (PCR). The factor XIII genotype was determined through a single-stranded conformational polymorphism. Fifty-eight patients and 48 controls showed the same band patterns on SSCP. In addition, we directly sequenced six random-selected DNA segments using DNA auto-sequencer. In conclusion, the results of this study suggest that FXIII Val34Leu be absent or rare both in patients with PICH and in healthy controls among Koreans.

A family case of beta-thalassemia minor and hemoglobin Queens: alpha 34 (B15) Leu-Arg

We report a Korean family case of beta-thalassemia minor and Hb Queens. This is the first case report of Hb Queens in Korea. A 43-year-old male and his four family members had beta-thalassemia minor which is very rare in Korea. Incidentally, an alpha chain variant with a high isoelectric point was also found in two other family members without clinical problems and was finally identified as alpha 34 (B15) Leu-Arg or Hemoglobin Queens.