77 research outputs found
Modulation of miR-204 expression during chondrogenesis
RUNX2 and SOX9 are two pivotal transcriptional regulators of chondrogenesis. It has been demonstrated that RUNX2 and SOX9 physically interact; RUNX2 transactivation may be inhibited by SOX9. In addition, RUNX2 exerts reciprocal inhibition on SOX9 transactivity. Epigenetic control of gene expression plays a major role in the alternative differentiation fates of stem cells; in particular, it has been reported that SOX9 can promote the expression of miRNA (miR)-204. Our aim was therefore to investigate the miR-204-5p role during chondrogenesis and to identify the relationship between this miR and the transcription factors plus downstream genes involved in chondrogenic commitment and differentiation. To evaluate the role of miR-204 in chondrogenesis, we performed in vitro transfection experiments by using Mesenchymal Stem Cells (MSCs). We also evaluated miR-204-5p expression in zebrafish models (adults and larvae). By silencing miR-204 during the early differentiation phase, we observed the upregulation of SOX9 and chondrogenic related genes compared to controls. In addition, we observed the upregulation of COL1A1 (a RUNX2 downstream gene), whereas RUNX2 expression of RUNX2 was slightly affected compared to controls. However, RUNX2 protein levels increased in miR-204-silenced cells. The positive effects of miR204 silencing on osteogenic differentiation were also observed in the intermediate phase of osteogenic differentiation. On the contrary, chondrocytes' maturation was considerably affected by miR-204 downregulation. In conclusion, our results suggest that miR-204 negatively regulates the osteochondrogenic commitment of MSCs, while it positively regulates chondrocytes' maturation
Spontaneous calcification process in primary renal cells from a medullary sponge kidney patient harbouring a GDNF mutation.
Medullary nephrocalcinosis is a hallmark of medullary sponge kidney (MSK). We had the opportunity to study a spontaneous calcification process
in vitro by utilizing the renal cells of a patient with MSK who was heterozygous for the c.-27 + 18G>A variant in the GDNF gene encoding
glial cell-derived neurotrophic factor. The cells were obtained by collagenase digestion of papillary tissues from the MSK patient and from two
patients who had no MSK or nephrocalcinosis. These cells were typed by immunocytochemistry, and the presence of mineral deposits was
studied using von Kossa staining, scanning electron microscopy analysis and an ALP assay. Osteoblastic lineage markers were studied using
immunocytochemistry and RT-PCR. Staminality markers were also analysed using flow cytometry, magnetic cell separation technology, immunocytochemistry
and RT-PCR. Starting from p2, MSK and control cells formed nodules with a behaviour similar to that of calcifying pericytes;
however, Ca2PO4 was only found in the MSK cultures. The MSK cells had morphologies and immunophenotypes resembling those of pericytes
or stromal stem cells and were positive for vimentin, ZO1, aSMA and CD146. In addition, the MSK cells expressed osteocalcin and osteonectin,
indicating an osteoblast-like phenotype. In contrast to the control cells, GDNF was down-regulated in the MSK cells. Stable GDNF knockdown
was established in the HK2 cell line and was found to promote Ca2PO4 deposition when the cells were incubated with calcifying medium by regulating
the osteonectin/osteopontin ratio in favour of osteonectin. Our data indicate that the human papilla may be a perivascular niche in which
pericyte/stromal-like cells can undergo osteogenic differentiation under particular conditions and suggest that GDNF down-regulation may have
influenced the observed phenomenon
Effects of oral administration of silymarin in a juvenile murine model of non-alcoholic steatohepatitis
The increasing prevalence of non-alcoholic fatty liver disease (NAFLD) in adolescents is challenging the global care system. No therapeutic strategies have been de\ufb01ned so far, and changes in the lifestyle remain the only alternative. In this study, we assessed the protective effects of silymarin in a juvenile non-alcoholic steatohepatitis (NASH) model and the in vitro effects on fat-laden human hepatocytes. C57Bl/6 mice were exposed to HFHC diet immediately after weaning. After eight weeks, animals showed histological signs of NASH. Silymarin was added to the HFHC diet, the treatment continued for additional 12 weeks and the effects on BMI, hepatomegaly, visceral fat, lipid pro\ufb01le, transaminases, HOMA-IR, steatosis, in\ufb02ammation, \ufb01brosis, oxidative stress, and apoptosis were determined. The switch from HFHC to control diet was used to mimic lifestyle changes. In vitro experiments were performed in parallel in human hepatocytes. HFHC diet supplemented with silymarin showed a signi\ufb01cant improvement in glycemia, visceral fat, lipid pro\ufb01le, and liver \ufb01brosis. Moreover, it reduced (both in vitro and in vivo) ALT, hepatic in\ufb02ammation, oxidative stress, and apoptosis. Lifestyle changes restored the control group parameters. The data presented show the bene\ufb01cial effects of the oral administration of silymarin in the absence of changes in the dietary habits in a juvenile model of NASH
Effects of oral administration of silymarin in a juvenile murine model of non-alcoholic steatohepatitis
The increasing prevalence of non-alcoholic fatty liver disease (NAFLD) in adolescents is challenging the global care system. No therapeutic strategies have been defined so far, and changes in the lifestyle remain the only alternative. In this study, we assessed the protective effects of silymarin in a juvenile non-alcoholic steatohepatitis (NASH) model and the in vitro effects on fat-laden human hepatocytes. C57Bl/6 mice were exposed to HFHC diet immediately after weaning. After eight weeks, animals showed histological signs of NASH. Silymarin was added to the HFHC diet, the treatment continued for additional 12 weeks and the effects on BMI, hepatomegaly, visceral fat, lipid profile, transaminases, HOMA-IR, steatosis, inflammation, fibrosis, oxidative stress, and apoptosis were determined. The switch from HFHC to control diet was used to mimic lifestyle changes. In vitro experiments were performed in parallel in human hepatocytes. HFHC diet supplemented with silymarin showed a significant improvement in glycemia, visceral fat, lipid profile, and liver fibrosis. Moreover, it reduced (both in vitro and in vivo) ALT, hepatic inflammation, oxidative stress, and apoptosis. Lifestyle changes restored the control group parameters. The data presented show the beneficial effects of the oral administration of silymarin in the absence of changes in the dietary habits in a juvenile model of NASH
Total Skin Electron Therapy Stanford Technique Evolution With Monte Carlo Simulation Toward Personalized Treatments For Cutaneous Lymphoma
Current Total Skin Electron Therapy (TSET) Stanford technique for cutaneous
lymphoma, established in the 70's, involves a unique irradiation setup, i.e.
patient's position and beam arrangement, for all patients with ensuing great
variability in dose distribution and difficult dose optimization. A
Geant4-based simulation has been developed to explore the possibility of
personalizing the dose to each patient's anatomy. To achieve this optimization
of the treatment method, this project enrolls different aspects of the clinical
and computational techniques: starting with the knowledge of the experimental
parameters involving TSET practice, passing through an innovative approach to
model the patient's anatomy, a precise description of the electron beam and a
validated configuration of the physics models handling the interactions of the
electrons and of secondary particles. The Geant4-based simulation models the
patient as a tessellated solid derived from the optical scan of her/his body,
realistically reproduces the irradiation environment in detail and calculates
the energy deposition corresponding to each facet of the patient's scanned
surface. The resulting three-dimensional dose distribution constitutes the
basis for the personalization of the medical treatement as appropriate to each
patient's specific characteristics.Comment: Presented at the 2022 IEEE Nuclear Science Symposiu
Severity of Hepatocyte Damage and Prognosis in Cirrhotic Patients Correlate with Hepatocyte Magnesium Depletion
We aimed to evaluate the magnesium content in human cirrhotic liver and its correlation
with serum AST levels, expression of hepatocellular injury, and MELDNa prognostic score. In liver
biopsies obtained at liver transplantation, we measured the magnesium content in liver tissue in
27 cirrhotic patients (CIRs) and 16 deceased donors with healthy liver (CTRLs) by atomic absorption
spectrometry and within hepatocytes of 15 CIRs using synchrotron-based X-ray fluorescence microscopy.
In 31 CIRs and 10 CTRLs, we evaluated the immunohistochemical expression in hepatocytes
of the transient receptor potential melastatin 7 (TRPM7), a magnesium influx chanzyme also involved
in inflammation. CIRs showed a lower hepatic magnesium content (117.2 (IQR 110.5–132.9) vs. 162.8
(IQR 155.9–169.8)  g/g; p < 0.001) and a higher percentage of TRPM7 positive hepatocytes (53.0
(IQR 36.8–62.0) vs. 20.7 (10.7–32.8)%; p < 0.001) than CTRLs. In CIRs, MELDNa and serum AST at
transplant correlated: (a) inversely with the magnesium content both in liver tissue and hepatocytes;
and (b) directly with the percentage of hepatocytes stained intensely for TRPM7. The latter also
directly correlated with the worsening of MELDNa at transplant compared to waitlisting. Magnesium
depletion and overexpression of its influx chanzyme TRPM7 in hepatocytes are associated with
severity of hepatocyte injury and prognosis in cirrhosis. These data represent the pathophysiological
basis for a possible beneficial effect of magnesium supplementation in cirrhotic patients
The Ischemic Stroke Genetics Study (ISGS) Protocol
BACKGROUND: The molecular basis for the genetic risk of ischemic stroke is likely to be multigenic and influenced by environmental factors. Several small case-control studies have suggested associations between ischemic stroke and polymorphisms of genes that code for coagulation cascade proteins and platelet receptors. Our aim is to investigate potential associations between hemostatic gene polymorphisms and ischemic stroke, with particular emphasis on detailed characterization of the phenotype. METHODS/DESIGN: The Ischemic Stroke Genetic Study is a prospective, multicenter genetic association study in adults with recent first-ever ischemic stroke confirmed with computed tomography or magnetic resonance imaging. Patients are evaluated at academic medical centers in the United States and compared with sex- and age-matched controls. Stroke subtypes are determined by central blinded adjudication using standardized, validated mechanistic and syndromic classification systems. The panel of genes to be tested for polymorphisms includes β-fibrinogen and platelet glycoprotein Ia, Iba, and IIb/IIIa. Immortalized cell lines are created to allow for time- and cost-efficient testing of additional candidate genes in the future. DISCUSSION: The study is designed to minimize survival bias and to allow for exploring associations between specific polymorphisms and individual subtypes of ischemic stroke. The data set will also permit the study of genetic determinants of stroke outcome. Having cell lines will permit testing of future candidate risk factor genes
A genome-wide association study of anorexia nervosa suggests a risk locus implicated in dysregulated leptin signaling
J. Kaprio, A. Palotie, A. Raevuori-Helkamaa ja S. Ripatti ovat työryhmän Eating Disorders Working Group of the Psychiatric Genomics Consortium jäseniä. Erratum in: Sci Rep. 2017 Aug 21;7(1):8379, doi: 10.1038/s41598-017-06409-3We conducted a genome-wide association study (GWAS) of anorexia nervosa (AN) using a stringently defined phenotype. Analysis of phenotypic variability led to the identification of a specific genetic risk factor that approached genome-wide significance (rs929626 in EBF1 (Early B-Cell Factor 1); P = 2.04 x 10(-7); OR = 0.7; 95% confidence interval (CI) = 0.61-0.8) with independent replication (P = 0.04), suggesting a variant-mediated dysregulation of leptin signaling may play a role in AN. Multiple SNPs in LD with the variant support the nominal association. This demonstrates that although the clinical and etiologic heterogeneity of AN is universally recognized, further careful sub-typing of cases may provide more precise genomic signals. In this study, through a refinement of the phenotype spectrum of AN, we present a replicable GWAS signal that is nominally associated with AN, highlighting a potentially important candidate locus for further investigation.Peer reviewe
Recommended from our members
A genome-wide association study of anorexia nervosa
Anorexia nervosa (AN) is a complex and heritable eating disorder characterized by dangerously low body weight. Neither candidate gene studies nor an initial genome wide association study (GWAS) have yielded significant and replicated results. We performed a GWAS in 2,907 cases with AN from 14 countries (15 sites) and 14,860 ancestrally matched controls as part of the Genetic Consortium for AN (GCAN) and the Wellcome Trust Case Control Consortium 3 (WTCCC3). Individual association analyses were conducted in each stratum and meta-analyzed across all 15 discovery datasets. Seventy-six (72 independent) SNPs were taken forward for in silico (two datasets) or de novo (13 datasets) replication genotyping in 2,677 independent AN cases and 8,629 European ancestry controls along with 458 AN cases and 421 controls from Japan. The final global meta-analysis across discovery and replication datasets comprised 5,551 AN cases and 21,080 controls. AN subtype analyses (1,606 AN restricting; 1,445 AN binge-purge) were performed. No findings reached genome-wide significance. Two intronic variants were suggestively associated: rs9839776 (P=3.01×10−7) in SOX2OT and rs17030795 (P=5.84×10−6) in PPP3CA. Two additional signals were specific to Europeans: rs1523921 (P=5.76×10−6) between CUL3 and FAM124B and rs1886797 (P=8.05×10−6) near SPATA13. Comparing discovery to replication results, 76% of the effects were in the same direction, an observation highly unlikely to be due to chance (P= 4×10−6), strongly suggesting that true findings exist but that our sample, the largest yet reported, was underpowered for their detection. The accrual of large genotyped AN case-control samples should be an immediate priority for the field
Canagliflozin and Cardiovascular and Renal Outcomes in Type 2 Diabetes Mellitus and Chronic Kidney Disease in Primary and Secondary Cardiovascular Prevention Groups
Background: Canagliflozin reduces the risk of kidney failure in patients with type 2 diabetes mellitus and chronic kidney disease, but effects on specific cardiovascular outcomes are uncertain, as are effects in people without previous cardiovascular disease (primary prevention). Methods: In CREDENCE (Canagliflozin and Renal Events in Diabetes With Established Nephropathy Clinical Evaluation), 4401 participants with type 2 diabetes mellitus and chronic kidney disease were randomly assigned to canagliflozin or placebo on a background of optimized standard of care. Results: Primary prevention participants (n=2181, 49.6%) were younger (61 versus 65 years), were more often female (37% versus 31%), and had shorter duration of diabetes mellitus (15 years versus 16 years) compared with secondary prevention participants (n=2220, 50.4%). Canagliflozin reduced the risk of major cardiovascular events overall (hazard ratio [HR], 0.80 [95% CI, 0.67-0.95]; P=0.01), with consistent reductions in both the primary (HR, 0.68 [95% CI, 0.49-0.94]) and secondary (HR, 0.85 [95% CI, 0.69-1.06]) prevention groups (P for interaction=0.25). Effects were also similar for the components of the composite including cardiovascular death (HR, 0.78 [95% CI, 0.61-1.00]), nonfatal myocardial infarction (HR, 0.81 [95% CI, 0.59-1.10]), and nonfatal stroke (HR, 0.80 [95% CI, 0.56-1.15]). The risk of the primary composite renal outcome and the composite of cardiovascular death or hospitalization for heart failure were also consistently reduced in both the primary and secondary prevention groups (P for interaction >0.5 for each outcome). Conclusions: Canagliflozin significantly reduced major cardiovascular events and kidney failure in patients with type 2 diabetes mellitus and chronic kidney disease, including in participants who did not have previous cardiovascular disease
- …