Non-syndromic cleft lip/palate (NSCL/P) is a complex, frequent congenital malformation, determined by the interplay between genetic and environmental factors during embryonic development. Previous findings have appointed an aetiological overlap between NSCL/P and cancer, and alterations in similar biological pathways may underpin both conditions. Here, using a combination of transcriptomic profiling and functional approaches, we report that NSCL/P dental pulp stem cells exhibit dysregulation of a co-expressed gene network mainly associated with DNA double-strand break repair and cell cycle control (p = 2.88×10−2–5.02×10−9). This network included important genes for these cellular processes, such as BRCA1, RAD51, and MSH2, which are predicted to be regulated by transcription factor E2F1. Functional assays support these findings, revealing that NSCL/P cells accumulate DNA double-strand breaks upon exposure to H2O2. Furthermore, we show that E2f1, Brca1 and Rad51 are co-expressed in the developing embryonic orofacial primordia, and may act as a molecular hub playing a role in lip and palate morphogenesis. In conclusion, we show for the first time that cellular defences against DNA damage may take part in determining the susceptibility to NSCL/P. These results are in accordance with the hypothesis of aetiological overlap between this malformation and cancer, and suggest a new pathogenic mechanism for the disease.
Nonsyndromic orofacial cleft (NSOFC) is a complex disease of still unclear genetic etiology. To investigate the contribution of rare epithelial cadherin (CDH1) gene variants to NSOFC, we target sequenced 221 probands. Candidate variants were evaluated via in vitro, in silico, or segregation analyses. Three probably pathogenic variants (c.760G>A [p.Asp254Asn], c.1023T>G [p.Tyr341*], and c.2351G>A [p.Arg784His]) segregated according to autosomal dominant inheritance in four nonsyndromic cleft lip with or without cleft palate (NSCL/P) families (Lod score: 5.8 at θ = 0; 47% penetrance). A fourth possibly pathogenic variant (c.387+5G>A) was also found, but further functional analyses are needed (overall prevalence of CDH1 candidate variants: 2%; 15.4% among familial cases). CDH1 mutational burden was higher among probands from familial cases when compared to that of controls (P = 0.002). We concluded that CDH1 contributes to NSCL/P with mainly rare, moderately penetrant variants, and CDH1 haploinsufficiency is the likely etiological mechanism.
The antioxidant and free radical scavenger properties of melatonin have been well described in the literature. In this study, our objective was to determine the protective effect of the pineal gland hormone against the DNA damage induced by cyclophosphamide (CP), an anti-tumor agent that is widely applied in clinical practice. DNA damage was induced in rats by a single intraperitoneal injection of CP (20 or 50 mg/kg). Animals received melatonin during the dark period for 15 days (1 mg/kg in the drinking water). Rat bone marrow cells were used for the determination of chromosomal aberrations and of formamidopyrimidine DNA glycosylase enzyme (Fpg)-sensitive sites by the comet technique and of Xpf mRNA expression by qRT-PCR. The number (mean ± SE) of chromosomal aberrations in pinealectomized (PINX) animals treated with melatonin and CP (2.50 ± 0.50/100 cells) was lower than that obtained for PINX animals injected with CP (12 ± 1.8/100 cells), thus showing a reduction of 85.8% in the number of chromosomal aberrations. This melatonin-mediated protection was also observed when oxidative lesions were analyzed by the Fpg-sensitive assay, both 24 and 48 h after CP administration. The expression of Xpf mRNA, which is involved in the DNA nucleotide excision repair machinery, was up-regulated by melatonin. The results indicate that melatonin is able to protect bone marrow cells by completely blocking CP-induced chromosome aberrations. Therefore, melatonin administration could be an alternative and effective treatment during chemotherapy.
Diphosphoinositol pentakisphosphate (IP7) is critical for the exocytotic capacity of the pancreatic β-cell, but its regulation by the primary instigator of β-cell exocytosis, glucose, is unknown. The high Km for ATP of the IP7-generating enzymes, the inositol hexakisphosphate kinases (IP6K1 and 2) suggests that these enzymes might serve as metabolic sensors in insulin secreting β-cells and act as translators of disrupted metabolism in diabetes. We investigated this hypothesis and now show that glucose stimulation, which increases the ATP/ADP ratio, leads to an early rise in IP7 concentration in β-cells. RNAi mediated knock down of the IP6K1 isoform inhibits both glucose-mediated increase in IP7 and first phase insulin secretion, demonstrating that IP6K1 integrates glucose metabolism and insulin exocytosis. In diabetic mouse islets the deranged ATP/ADP levels under both basal and glucose-stimulated conditions are mirrored in both disrupted IP7 generation and insulin release. Thus the unique metabolic sensing properties of IP6K1 guarantees appropriate concentrations of IP7 and thereby both correct basal insulin secretion and intact first phase insulin release. In addition, our data suggest that a specific cell signaling defect, namely, inappropriate IP7 generation may be an essential convergence point integrating multiple metabolic defects into the commonly observed phenotype in diabetes.
Background/Aims: Several studies have been performed to unravel the association between diabetes and increased susceptibility to infection. This study aimed to investigate the effect of insulin on the local environment after cecal ligation and puncture (CLP) in rats. Methods: Diabetic (alloxan, 42 mg/kg i.v., 10 days) and non-diabetic (control) male Wistar rats were subjected to a two-puncture CLP procedure and 6 h later, the following analyses were performed: (a) total and differential cell counts in peritoneal lavage (PeL) and bronchoalveolar lavage (BAL) fluids; (b) quantification of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-10 and cytokine-induced neutrophil chemoattractant (CINC)-1 and CINC-2 in the PeL and BAL fluids by enzyme-linked immunosorbent assay (ELISA); (c) total leukocyte count using a veterinary hematology analyzer and differential leukocyte counts on stained slides; (d) biochemical parameters (urea, creatinine, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) by colorimetric analyses); and (e) lung, kidney, and liver morphological analyses (hematoxylin and eosin staining). Results: Relative to controls, non-diabetic and diabetic CLP rats exhibited an increased in the concentration of IL-1β, IL-6, IL-10, CINC-1, and CINC-2 and total and neutrophil in the PeL fluid. Treatment of these animals with neutral protamine Hagedorn insulin (NPH, 1IU and 4IU, respectively, s.c.), 2 hours before CLP procedure, induced an increase on these cells in the PeL fluid but it did not change cytokine levels. The levels of ALT, AST, ALP, and urea were higher in diabetic CLP rats than in non-diabetic CLP rats. ALP levels were higher in diabetic sham rats than in non-diabetic sham rats. Treatment of diabetic rats with insulin completely restored ALT, AST, and ALP levels. Conclusion: These results together suggest that insulin attenuates liver dysfunction during early two-puncture CLP-induced peritoneal inflammation in diabetic rats.
IntroductionThe role of insulin in lung remodeling in a model of asthma in healthy and diabetic mice was evaluated.Material and methodsDiabetic male BALB/c mice (alloxan, 50 mg/kg, intravenous) and controls were sensitized by subcutaneous (s.c.) injection of ovalbumin (OA, 20 µg) in aluminum hydroxide (Al(OH)3, 2 mg) 10 days after the alloxan injection and received the same dose 12 days later. Six days after the last sensitization, animals were nebulized with OA solution for 7 days. The first set of diabetic and control mice received 2 and 1 IU, respectively, of s.c. neutral protamine Hagedorn (NPH) insulin and were analyzed 8 h later. The second set of diabetic and control mice received 2 and 1 IU, respectively, of insulin 12 h before the OA challenge and half doses of insulin 2 h before each the seven OA challenges. Twenty-four hours after the last challenge, the following analyses were performed: (a) quantification of the cells in the bronchoalveolar lavage fluid (BALF), the white cell count, and blood glucose; (b) morphological analysis of lung tissues by hematoxylin and eosin staining; (c) quantification of collagen deposition in lung tissues and mucus by morphometric analysis of histological sections stained with Masson’s trichrome and periodic acid-Schiff (PAS), respectively; and (d) quantification of the cytokine concentrations (IL-4, IL-5, and IL-13) in the BALF supernatant.ResultsCompared to controls, diabetic mice had significantly reduced inflammatory cells (81%) in the BALF, no eosinophils in the BALF and peripheral blood and reduced collagen deposition and mucus in the lungs. BALF concentrations of IL-4 (48%) and IL-5 (31%) decreased and IL-13 was absent. A single dose of insulin restored peripheral blood eosinophils and BALF mononuclear cells but not BALF eosinophils, collagen deposition, and mucus levels. However, multiple doses of insulin restored both total cells and eosinophils in the BALF and peripheral blood, BALF cytokines, and collagen deposition and mucus secretion into the lungs.ConclusionThe results suggest that insulin modulates the production/release of cytokines, cell migration, deposition of collagen, and mucus secretion in lung remodeling of a mouse model of asthma.
Brain death (BD) affects organs by multiple mechanisms related to hemodynamic effects, hormonal changes, and the systemic inflammatory response, which reduce organ function and viability. BD reduces microcirculatory perfusion in rat mesentery; this disturbance is also observed in the pancreas and lungs. Sex hormones can affect microcirculatory function, altering tissue perfusion and influencing the inflammatory process. Here, we present differences between sexes in the microcirculatory alterations generated by BD and in inflammatory infiltrate. Male, female, and ovariectomized-female Wistar rats were submitted to BD by intracranial balloon catheter sudden inflation. BD was confirmed by maximally dilated and fixed pupils, apnea, absence of reflexes, and a drop in mean arterial pressure. Perfusion and flow of the mesenteric microcirculation were analyzed. Intestinal myeloperoxidase activity and leukocyte infiltration were quantified. ELISA quantified serum estradiol, corticosterone, and inflammatory mediators, whereas expression of eNOS, endothelin, and endothelial adhesion molecule was measured by immunohistochemistry. Male rats presented lower percentages of mesenteric perfused microvessels and reduced blood flow compared to females. The female group presented higher eNOS and endothelin expression. Leukocyte infiltration into intestinal walls was higher in females in comparison to that in males. Moreover, the female group showed higher mesenteric vessel ICAM-1 expression than males, whereas serum TNF-α, IL-1β, and IL-10 levels did not differ between sexes. The high estradiol concentration before BD and high eNOS expression apparently favored the maintenance of microvascular perfusion/flow; however, BD caused an acute reduction of female sex hormone concentration and higher ICAM-1 level; thus, the proinflammatory organ status after BD is favored.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
334 Leonard St
Brooklyn, NY 11211
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.