Paeonicluside,a new salicylic glycoside from the Greek endemic species Paeonia clusii

A new glycoside of salicylic aldehyde, paeonicluside, was isolated from the roots of the Greek endemic species Paeonia clusii subsp. clusii and identified as alpha-L-arabinopyranosyl-(1-->6)-O-beta-D-glucopyranoside of salicylic aldehyde (1). In addition, one characteristic monoterpene and two monoterpene glycosides were identified as paeoniflorigenone, paeoniflorin and benzoyl paeoniflorin, respectively. The structure of 1 was elucidated on the basis of its spectroscopic data and chemical correlation. It is the first time that a derivative of salicylic aldehyde is isolated from the well-studied Paeonia genus.     

Identification and Characterisation of the Murine Homologue of the Gene Responsible for Cystinosis, Ctns

Background  

Cystinosis is an autosomal recessive disorder characterised by an intralysosomal accumulation of cystine, and affected individuals progress to end-stage renal failure before the age of ten. The causative gene, CTNS, was cloned in 1998 and the encoded protein, cystinosin, was predicted to be a lysosomal membrane protein.     

Metabolic Profile in Early Pregnancy Is Associated with Offspring Adiposity at 4 Years of Age: The Rhea Pregnancy Cohort Crete,Greece

ContextMaternal pre-pregnancy obesity may increase the risk of childhood obesity but it is unknown whether other metabolic factors in early pregnancy such as lipid profile and hypertension are associated with offspring cardiometabolic traits.ObjectiveOur objective was to investigate whether fasting lipid, glucose, and insulin levels during early pregnancy and maternal pre-pregnancy weight status, are associated with offspring adiposity measures, lipid levels and blood pressure at preschool age.ResultsPre-pregnancy overweight/obesity was associated with greater risk of offspring overweight/obesity (RR: 1.83, 95%CI: 1.19, 2.81), central adiposity (RR: 1.97, 95%CI: 1.11, 3.49), and greater fat mass by 5.10mm (95%CI: 2.49, 7.71) at 4 years of age. These associations were more pronounced in girls. An increase of 40mg/dl in fasting serum cholesterol levels in early pregnancy was associated with greater skinfold thickness by 3.30mm (95%CI: 1.41, 5.20) at 4 years of age after adjusting for pre-pregnancy BMI and several other confounders. An increase of 10mmHg in diastolic blood pressure in early pregnancy was associated with increased risk of offspring overweight/obesity (RR: 1.22, 95%CI: 1.03, 1.45), and greater skinfold thickness by 1.71mm (95% CI: 0.57, 2.86) at 4 years of age.ConclusionsMetabolic dysregulation in early pregnancy may increase the risk of obesity at preschool age.     

Macitentan inhibits the transforming growth factor-β profibrotic action,blocking the signaling mediated by the ETR/TβRI complex in systemic sclerosis dermal fibroblasts

IntroductionSystemic sclerosis (SSc) is a complex and not fully understood autoimmune disease associated with fibrosis of multiple organs. The main effector cells, the myofibroblasts, are collagen-producing cells derived from the activation of resting fibroblasts. This process is regulated by a complex repertoire of profibrotic cytokines, and among them transforming growth factor beta (TGF-β) and endothelin-1 (ET-1) play a major role. In this paper we show that TGF-β and ET-1 receptors co-operate in myofibroblast activation, and macitentan, an ET-1 receptor antagonist binding ET-1 receptors, might interfere with both TGF-β and ET-1 pathways, preventing myofibroblast differentiation.MethodsFibroblasts isolated from healthy controls and SSc patients were treated with TGF-β and ET-1 and successively analyzed for alpha smooth muscle actin (α-SMA) and collagen (Col1A1) expression and for the Sma and Mad Related (SMAD) phosphorylation. We further tested the ability of macitentan to interfere with these process. Furthermore, we silenced ET-1 and endothelin-1 receptor A expression and evaluated the formation of an ET-1/TGF-β receptor complex by immunoprecitation assay.ResultsWe showed myofibroblast activation in SSc fibroblasts assessing the expression of α-SMA and Col1A1, after stimulation with TGF-β and ET-1. Macitentan interfered with both ET-1- and TGF-β-induced fibroblast activation. To explain this unexpected inhibitory effect of macitentan on TGF-β activity, we silenced ET-1 expression on SSc fibroblasts and co-immunoprecipitated these two receptors, showing the formation of an ET-1/TGF-β receptor complex.ConclusionsDuring SSc, ET-1 produced by activated endothelia contributes to myofibroblast activation using TGF-β machinery via an ET-1/TGF-β receptor complex. Macitentan interferes with the profibrotic action of TGF-β, blocking the ET-1 receptor portion of the ET-1/TGF-β receptor complex.     

A computational study of the Warburg effect identifies metabolic targets inhibiting cancer migration

Over the last decade, the field of cancer metabolism has mainly focused on studying the role of tumorigenic metabolic rewiring in supporting cancer proliferation. Here, we perform the first genome‐scale computational study of the metabolic underpinnings of cancer migration. We build genome‐scale metabolic models of the NCI‐60 cell lines that capture the Warburg effect (aerobic glycolysis) typically occurring in cancer cells. The extent of the Warburg effect in each of these cell line models is quantified by the ratio of glycolytic to oxidative ATP flux (AFR), which is found to be highly positively associated with cancer cell migration. We hence predicted that targeting genes that mitigate the Warburg effect by reducing the AFR may specifically inhibit cancer migration. By testing the anti‐migratory effects of silencing such 17 top predicted genes in four breast and lung cancer cell lines, we find that up to 13 of these novel predictions significantly attenuate cell migration either in all or one cell line only, while having almost no effect on cell proliferation. Furthermore, in accordance with the predictions, a significant reduction is observed in the ratio between experimentally measured ECAR and OCR levels following these perturbations. Inhibiting anti‐migratory targets is a promising future avenue in treating cancer since it may decrease cytotoxic‐related side effects that plague current anti‐proliferative treatments. Furthermore, it may reduce cytotoxic‐related clonal selection of more aggressive cancer cells and the likelihood of emerging resistance.     

Coexistence of tumor-induced osteomalacia and primary hyperparathyroidism

ObjectiveTo present an unusual case of coexisting tumor-induced osteomalacia (TIO) and primary hyperparathyroidism (PHPT).MethodsWe report the clinical features, imaging studies, and the results of laboratory investigations before and after surgical resection of both a soft-tissue tumor and a parathyroid adenoma.ResultsA 44-year-old woman was referred to the endocrinology department with a diagnosis of PHPT accompanied by unusually severe hypophosphatemia, despite having received treatment with cinacalcet. Debilitating muscle weakness and bone pain, severe phosphaturia and hypophosphatemia, inappropriately normal calcitriol, and elevated fibroblast growth factor-23 and intact parathyroid hormone levels raised the suspicion of coexisting TIO and PHPT. Imaging studies were negative, but histologic characteristics of a palpable subcutaneous mass from the patient’s thigh revealed a phosphaturic mesenchymal tumor. Complete remission after surgical removal of both the soft-tissue tumor and the parathyroid adenoma confirmed the diagnosis.ConclusionThe coexistence of TIO and PHPT has not been described before and can cause life-threatening hypophosphatemia. Diagnosis and localization of the tumor is of paramount importance since surgery is the treatment of choice for both TIO and PHPT. (Endocr Pract. 2011;17:e144-e148)     

In vitro and in vivo properties of distinct populations of amniotic fluid mesenchymal progenitor cells

Human mesenchymal progenitor cells (MPCs) are considered to be of great promise for use in tissue repair and regenerative medicine. MPCs represent multipotent adherent cells, able to give rise to multiple mesenchymal lineages such as osteoblasts, adipocytes or chondrocytes. Recently, we identified and characterized human second trimester amniotic fluid (AF) as a novel source of MPCs. Herein, we found that early colonies of AF-MPCs consisted of two morphologically distinct adherent cell types, termed as spindle-shaped (SS) and round-shaped (RS). A detailed analysis of these two populations showed that SS-AF-MPCs expressed CD90 antigen in a higher level and exhibited a greater proliferation and differentiation potential. To characterize better the molecular identity of these two populations, we have generated a comparative proteomic map of SS-AF-MPCs and RS-AF-MPCs, identifying 25 differentially expressed proteins and 10 proteins uniquely expressed in RS-AF-MPCs. Furthermore, SS-AF-MPCs exhibited significantly higher migration ability on extracellular matrices, such as fibronectin and laminin in vitro, compared to RS-AF-MPCs and thus we further evaluated SS-AF-MPCs for potential use as therapeutic tools in vivo. Therefore, we tested whether GFP-lentiviral transduced SS-AF-MPCs retained their stem cell identity, proliferation and differentiation potential. GFP-SS-AF-MPCs were then successfully delivered into immunosuppressed mice, distributed in different tissues and survived longterm in vivo. In summary, these results demonstrated that AF-MPCs consisted of at least two different MPC populations. In addition, SS-AF-MPCs, isolated based on their colony morphology and CD90 expression, represented the only MPC population that can be expanded easily in culture and used as an efficient tool for future in vivo therapeutic applications.     

Reversal in competitive dominance of a toxic versus non-toxic cyanobacterium in response to rising CO2

Climate change scenarios predict a doubling of the atmospheric CO₂ concentration by the end of this century. Yet, how rising CO₂ will affect the species composition of aquatic microbial communities is still largely an open question. In this study, we develop a resource competition model to investigate competition for dissolved inorganic carbon in dense algal blooms. The model predicts how dynamic changes in carbon chemistry, pH and light conditions during bloom development feed back on competing phytoplankton species. We test the model predictions in chemostat experiments with monocultures and mixtures of a toxic and non-toxic strain of the freshwater cyanobacterium Microcystis aeruginosa. The toxic strain was able to reduce dissolved CO₂ to lower concentrations than the non-toxic strain, and became dominant in competition at low CO₂ levels. Conversely, the non-toxic strain could grow at lower light levels, and became dominant in competition at high CO₂ levels but low light availability. The model captured the observed reversal in competitive dominance, and was quantitatively in good agreement with the results of the competition experiments. To assess whether microcystins might have a role in this reversal of competitive dominance, we performed further competition experiments with the wild-type strain M. aeruginosa PCC 7806 and its mcyB mutant impaired in microcystin production. The microcystin-producing wild type had a strong selective advantage at low CO₂ levels but not at high CO₂ levels. Our results thus demonstrate both in theory and experiment that rising CO₂ levels can alter the community composition and toxicity of harmful algal blooms.     

Mutation analysis of NR5A1 encoding steroidogenic factor 1 in 77 patients with 46, XY disorders of sex development (DSD) including hypospadias

Background

Mutations of the NR5A1 gene encoding steroidogenic factor-1 have been reported in association with a wide spectrum of 46,XY DSD (Disorder of Sex Development) phenotypes including severe forms of hypospadias.

Methodology/Principal Findings

We evaluated the frequency of NR5A1 gene mutations in a large series of patients presenting with 46,XY DSD and hypospadias. Based on their clinical presentation 77 patients were classified either as complete or partial gonadal dysgenesis (uterus seen at genitography and/or surgery, n = 11), ambiguous external genitalia without uterus (n = 33) or hypospadias (n = 33). We identified heterozygous NR5A1 mutations in 4 cases of ambiguous external genitalia without uterus (12.1%; p.Trp279Arg, pArg39Pro, c.390delG, c140_141insCACG) and a de novo missense mutation in one case with distal hypospadias (3%; p.Arg313Cys). Mutant proteins showed reduced transactivation activity and mutants p.Arg39Pro and p.Arg313Cys did not synergize with the GATA4 cofactor to stimulate reporter gene activity, although they retained their ability to physically interact with the GATA4 protein.

Conclusions/Significance

Mutations in NR5A1 were observed in 5/77 (6.5%) cases of 46,XY DSD including hypospadias. Excluding the cases of 46,XY gonadal dysgenesis the incidence of NR5A1 mutations was 5/66 (7.6%). An individual with isolated distal hypopadias carried a de novo heterozygous missense mutation, thus extending the range of phenotypes associated with NR5A1 mutations and suggesting that this group of patients should be screened for NR5A1 mutations.     

The production of a key floral volatile is dependent on UV light in a sexually deceptive orchid

Background and Aims

Plants use a diverse range of visual and olfactory cues to advertize to pollinators. Australian Chiloglottis orchids employ one to three related chemical variants, all 2,5-dialkylcyclohexane-1,3-diones or ‘chiloglottones’ to sexually attract their specific male pollinators. Here an investigation was made of the physiological aspects of chiloglottone synthesis and storage that have not previously been examined.

Methods

The location of chiloglottone production was determined and developmental and diurnal changes by GC-MS analysis of floral tissue extracts was monitored in two distantly related Chiloglottis species. Light treatment experiments were also performed using depleted flowers to evaluate if sunlight is required for chiloglottone production; which specific wavelengths of light are required was also determined.

Key Results

Chiloglottone production only occurs in specific floral tissues (the labellum calli and sepals) of open flowers. Upon flower opening chiloglottone production is rapid and levels remain more or less stable both day and night, and over the 2- to 3-week lifetime of the flower. Furthermore, it was determined that chiloglottone production requires continuous sunlight, and determined the optimal wavelengths of sunlight in the UV-B range (with peak of 300 nm).

Conclusions

UV-B light is required for the synthesis of chiloglottones – the semiochemicals used by Chiloglottis orchids to sexually lure their male pollinators. This discovery appears to be the first case to our knowledge where plant floral odour production depends on UV-B radiation at normal levels of sunlight. In the future, identification of the genes and enzymes involved, will allow us to understand better the role of UV-B light in the biosynthesis of chiloglottones.