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Friedreich's ataxia (FRDA), the most common inherited ataxia, is characterized by focal neurodegeneration, diabetes mellitus and life-threatening cardiomyopathy. Frataxin, which is significantly reduced in patients with this recessive disorder, is a mitochondrial iron-binding protein, but how its deficiency leads to neurodegeneration and metabolic derangements is not known. We performed microarray analysis of heart and skeletal muscle in a mouse model of frataxin deficiency, and found molecular evidence of increased lipogenesis in skeletal muscle, and alteration of fiber-type composition in heart, consistent with insulin resistance and cardiomyopathy, respectively. Since the peroxisome proliferator-activated receptor gamma (PPARgamma) pathway is known to regulate both processes, we hypothesized that dysregulation of this pathway could play a key role in frataxin deficiency. We confirmed this by showing a coordinate dysregulation of the PPARgamma coactivator Pgc1a and transcription factor Srebp1 in cellular and animal models of frataxin deficiency, and in cells from FRDA patients, who have marked insulin resistance. Finally, we show that genetic modulation of the PPARgamma pathway affects frataxin levels in vitro, supporting PPARgamma as a novel therapeutic target in FRDA.

Inherited ichthyoses are a group of clinically and genetically heterogeneous rare disorders of skin keratinization with overlapping phenotypes. The clinical picture and family history are crucial to formulating the diagnostic hypothesis, but only the identification of the genetic defect allows the correct classification. In the attempt to molecularly classify 17 unrelated Italian patients referred with congenital nonsyndromic ichthyosis, we performed massively parallel sequencing of over 50 ichthyosis-related genes. Genetic data of 300 Italian unaffected subjects were also analyzed to evaluate frequencies of putative disease-causing alleles in our population. For all patients, we identified the molecular cause of the disease. Eight patients were affected by autosomal recessive congenital ichthyosis associated with ALOX12B, NIPAL4, and TGM1 mutations. Three patients had biallelic loss-of-function variants in FLG, whereas 6/11 males were affected by X-linked ichthyosis. Among the 24 different disease-causing alleles we identified, 8 carried novel variants, including a synonymous TGM1 variant that resulted in a splicing defect. Moreover, we generated a priority list of the ichthyosis-related genes that showed a significant number of rare and novel variants in our population. In conclusion, our comprehensive molecular analysis resulted in an effective first-tier test for the early classification of ichthyosis patients. It also expands the genetic, mutational, and phenotypic spectra of inherited ichthyosis and provides new insight into the current understanding of etiologies and epidemiology of this group of rare disorders. [ABSTRACT FROM AUTHOR]

[PGE.sub.2] plays a critical role in colorectal carcinogenesis. We have previously shown that COX-2 expression and [PGE.sub.2] synthesis are mediated by IGF-II/IGF-I receptor signaling in the Caco-2 cell line and that the pathway of phosphatidylinositol 3-kinase (PI3K)/Akt protects the cell from apoptosis. In the present study, we demonstrate that [PGE.sub.2] has the ability to increase Ras and PI3K association and decrease the level of apoptosis in the same experimental system. The effect of [PGE.sub.2] on PI3K/Ras association is dependent on the activation of EP4 receptor, the increase of cAMP levels, and the activation of PKA. In fact, treatment of cells with the PKA inhibitor H89 decreases the association of Ras and PI3K and Ras-associated PI3K activity. PKA inhibitor H89 is able to decrease threonine phosphorylation of Akt and to increase serine phosphorylation of Akt by p38 MAPK and counteracts the cytoprotective effect induced by [PGE.sub.2]. In addition, [PGE.sub.2] is able to activate p38 MAPK and the inhibition of p38 MAPK, with SB203580 specific inhibitor or with dominant negative MKK6 kinase, is able to revert the apoptotic effect of H89 and serine phosphorylation of Akt. The effect of [PGE.sub.2] on Caco-2 cell survival through PKA activation is mediated and regulated by the balance of threonine/serine phosphorylation of Akt by p38 kinase and PI3K. In conclusion, our data elucidate a novel mechanism for regulation of colon cancer cell survival and provide evidences for new combinatory treatments of colon cancer. colon cancer; prostaglandin [E.sub.2]; Akt; protein kinase A; phosphatidylinositol 3-kinase

Abstract Background It is widely accepted that Type 2 Diabetes Mellitus (T2DM) and other complex diseases are the product of complex interplay between genetic susceptibility and environmental causes. To cope with such a complexity, all the statistical and conceptual strategies available should be used. The working hypothesis of this study was that two well-known T2DM risk factors could have diverse effect in individuals carrying different genotypes. In particular, our effort was to investigate if a well-defined group of genes, involved in peripheral energy expenditure, could modify the impact of two environmental factors like age and obesity on the risk to develop diabetes. To achieve this aim we exploited a multianalytical approach also using dimensionality reduction strategy and conservative significance correction strategies. Methods We collected clinical data and characterised five genetic variants and 2 environmental factors of 342 ambulatory T2DM patients and 305 unrelated non-diabetic controls. To take in account the role of one of the major co-morbidity conditions we stratified the whole sample according to the presence of obesity, over and above the 30 Kg/m2 BMI threshold. Results By monofactorial analyses the ADRB2-27 Glu27 homozygotes had a lower frequency of diabetes when compared with Gln27 carriers (Odds Ratio (OR) 0.56, 95% Confidence Interval (CI) 0.36 – 0.91). This difference was even more marked in the obese subsample. Multifactor Dimensionality Reduction method in the non-obese subsample showed an interaction among age, ADRB2-16 and UCP3 polymorphisms. In individuals that were UCP3 T-carriers and ADRB2-16 Arg-carriers the OR increased from 1 in the youngest to 10.84 (95% CI 4.54–25.85) in the oldest. On the contrary, in the ADRB2-16 GlyGly and UCP3 CC double homozygote subjects, the OR for the disease was 1.10 (95% CI 0.53–2.27) in the youngest and 1.61 (95% CI 0.55–4.71) in the oldest. Conclusion Although our results should be confirmed by further studies, our data suggests that, when properly evaluated, it is possible to identify genetic factors that could influence the effect of common risk factors.

MODY2 is the most prevalent monogenic form of diabetes in Italy with an estimated prevalence of about 0.5–1.5%. MODY2 is potentially indistinguishable from other forms of diabetes, however, its identification impacts on patients' quality of life and healthcare resources. Unfortunately, DNA direct sequencing as diagnostic test is not readily accessible and expensive. In addition current guidelines, aiming to establish when the test should be performed, proved a poor detection rate. Aim of this study is to propose a reliable and easy-to-use tool to identify candidate patients for MODY2 genetic testing. We designed and validated a diagnostic flowchart in the attempt to improve the detection rate and to increase the number of properly requested tests. The flowchart, called 7-iF, consists of 7 binary “yes or no” questions and its unequivocal output is an indication for whether testing or not. We tested the 7-iF to estimate its clinical utility in comparison to the clinical suspicion alone. The 7-iF, in a prospective 2-year study (921 diabetic children) showed a precision of about the 76%. Using retrospective data, the 7-iF showed a precision in identifying MODY2 patients of about 80% compared to the 40% of the clinical suspicion. On the other hand, despite a relatively high number of missing MODY2 patients, the 7-iF would not suggest the test for 90% of the non-MODY2 patients, demonstrating that a wide application of this method might 1) help less experienced clinicians in suspecting MODY2 patients and 2) reducing the number of unnecessary tests. With the 7-iF, a clinician can feel confident of identifying a potential case of MODY2 and suggest the molecular test without fear of wasting time and money. A Qaly-type analysis estimated an increase in the patients' quality of life and savings for the health care system of about 9 million euros per year. [ABSTRACT FROM AUTHOR]

Friedreich’s ataxia (FRDA) is a neurodegenerative disease due to a pathological expansion of a GAA triplet repeat in the first intron of the FXN gene encoding for the mitochondrial protein frataxin. The expansion is responsible for most cases of FRDA through the formation of a nonusual B-DNA structure and heterochromatin conformation that determine a direct transcriptional silencing and the subsequent reduction in frataxin expression. Among other functions, frataxin is an iron chaperone central for the assembly of iron–sulfur clusters in mitochondria; its reduction is associated with iron accumulation in mitochondria, increased cellular sensitivity to oxidative stress and cell damage. There is, nowadays, no effective therapy for FRDA and current therapeutic strategies mainly act to slow down the consequences of frataxin deficiency. Therefore, drugs that are able to increase the amount of frataxin are excellent candidates for a rational approach to FRDA therapy. Recently, several drugs have been assessed for their ability to increase the amount of cellular frataxin, including human recombinant erythropoietin, histone deacetylase inhibitors, and the PPAR-γ agonists. [ABSTRACT FROM AUTHOR]