Flavonoids and darkness lower PCD in senescing Vitis vinifera suspension cell cultures

Background Senescence is a key developmental process occurring during the life cycle of plants that can be induced also by environmental conditions, such as starvation and/or darkness. During senescence, strict control of genes regulates ordered degradation and dismantling events, the most remarkable of which are genetically programmed cell death (PCD) and, in most cases, an upregulation of flavonoid biosynthesis in the presence of light. Flavonoids are secondary metabolites that play multiple essential roles in development, reproduction and defence of plants, partly due to their well-known antioxidant properties, which could affect also the same cell death machinery. To understand further the effect of endogenously-produced flavonoids and their interplay with different environment (light or dark) conditions, two portions (red and green) of a senescing grapevine callus were used to obtain suspension cell cultures. Red Suspension cell Cultures (RSC) and Green Suspension cell Cultures (GSC) were finally grown under either dark or light conditions for 6 days. Results Darkness enhanced cell death (mainly necrosis) in suspension cell culture, when compared to those grown under light condition. Furthermore, RSC with high flavonoid content showed a higher viability compared to GSC and were more protected toward PCD, in accordance to their high content in flavonoids, which might quench ROS, thus limiting the relative signalling cascade. Conversely, PCD was mainly occurring in GSC and further increased by light, as it was shown by cytochrome c release and TUNEL assays. Conclusions Endogenous flavonoids were shown to be good candidates for exploiting an efficient protection against oxidative stress and PCD induction. Light seemed to be an important environmental factor able to induce PCD, especially in GSC, which lacking of flavonoids were not capable of preventing oxidative damage and signalling leading to senescence

Redeveloping the Riachuelo Building in São Paulo’s Historic Downtown

The Riachuelo building with its 17 floors was designed and built between 1942 and 1945 by the engineers Lindenberg & Assumpção. Its first owner was the São Paulo’s Association of Commerce Employees, which occupied only a few floors with social activities. The units in remaining floors were individually sold. The Association left the building in 1978, and the space it occupied was used by an accounting school. When the school left, the building gradually became empty until it was invaded by homeless people in 1994. The expulsion of the invaders by the police led to the deep depredation, including destruction of the property’s doors, windows, toilets, elevators and rainwater plumbing. During the administration of Mayor Marta Suplicy (2000/2004), the program Morar no Centro was created aiming to occupy São Paulo’s historic downtown, not only with municipal administration offices, but also with residents in a "social lease" system. In 2004, Paulo Bruna Arquitetos was hired by Cohab-SP to rehabilitate the building. The recovery sought to respect the original constructive logic in 5,554 square foot of land area and the 84,717 square foot total constructed area. The solid brick walls that separated the different offices were kept since they are part of the structure’s bracing, so basically every office was turned into an apartment, in a total of 120 units, ranging from 301 square foot to 516 square foot of floor space. Many of them include private balconies and balcony doors, and those were kept because the façade has been listed as historical heritage. The apartments were eventually sold and their residents value and maintain the building in an exemplary way.O Edifício Riachuelo foi projetado e construído entre 1942 e 1945 pelos engenheiros Lindenberg & Assumpção, com 17 pavimentos. O primeiro proprietário foi a Associação de Empregados do Comércio de São Paulo, que ocupava apenas alguns andares com atividades sociais. Os demais foram vendidos. O espaço ocupado pela Associação, após 1978, foi utilizado por uma escola de contabilidade e, quando esta saiu, o edifício foi ficando pouco a pouco vazio. Em 1994, foi invadido por moradores de rua. A expulsão dos invasores pelos policiais acarretou uma profunda depredação do imóvel, com destruição de portas, janelas, sanitários, elevadores e prumadas de águas pluviais. A Prefeita Marta Suplicy, durante seu governo (2000/2004), iniciou o programa Morar no Centro, que visava a ocupação do centro histórico, não apenas por setores da administração municipal, mas também por moradores em um sistema de “locação social”. Em 2004, o escritório Paulo Bruna Arquitetos foi contratado pela Cohab-SP para reabilitar o edifício. A área do terreno é de 516m2 e a área total construída é de 7.870,54m2. A recuperação procurou respeitar a lógica construtiva original. Entre os salões de escritórios havia paredes de alvenarias de tijolos maciços que foram mantidas porque são integradas no contraventamento da estrutura. Assim, basicamente cada escritório transformou-se em um apartamento. Foi possível acomodar 120 unidades, variando de 28m2 a 48m2 de área útil. Muitos têm balcões e portas-janelas privativas, que foram mantidos, pois a fachada foi classificada como bem de valor histórico. Os apartamentos acabaram sendo vendidos e os moradores valorizam e conservaram o condomínio de maneira exemplar

The permeability transition in plant mitochondria: The missing link

The synthesis of ATP in mitochondria is dependent on a low permeability of the inner membrane. Nevertheless, mitochondria can undergo an increased permeability to solutes, named permeability transition (PT) that is mediated by a pore (PTP). PTP opening requires matrix Ca2+ and leads to mitochondrial swelling and release of intramembrane space proteins (e.g. cytochrome c). This feature has been initially observed in mammalian mitochondria and tentatively attributed to some components present either in the outer or inner membrane. Recent works on mammalian mitochondria point to mitochondrial ATP synthase dimers as physical basis for PT, a finding that has been substantiated in yeast and Drosophila mitochondria. In plant mitochondria, swelling and release of proteins have been linked to programmed cell death, but in isolated mitochondria PT has been observed in only a few cases and in plant cell cultures only indirect evidence is available. The possibility that mitochondrial ATP synthase dimers could function as PTP also in plants is discussed here on the basis of the current evidence. Finally, a hypothetical explanation for the origin of PTP is provided in the framework of molecular exaptation

Properties of the permeability transition of pea stem mitochondria

In striking analogy with Saccharomyces cerevisiae, etiolated pea stem mitochondria did not show appreciable Ca2+ uptake. Only treatment with the ionophore ETH129 (which allows electrophoretic Ca2+ equilibration) caused Ca2+ uptake followed by increased inner membrane permeability, membrane depolarization and Ca2+ release. Like the permeability transition (PT) of mammals, yeast and Drosophila, the PT of pea stem mitochondria was stimulated by diamide and phenylarsine oxide and inhibited by MgADP and Mg-ATP, suggesting a common underlying mechanism; yet, the plant PT also displayed distinctive features: (i) as in mammals it was desensitized by cyclosporin A, which does not affect the PT of yeast and Drosophila; (ii) similarly to S. cerevisiae and Drosophila it was inhibited by Pi, which stimulates the PT of mammals; (iii) like in mammals and Drosophila it was sensitized by benzodiazepine 423, which is ineffective in S. cerevisiae; (iv) like what observed in Drosophila it did not mediate swelling and cytochrome c release, which is instead seen in mammals and S. cerevisiae. We find that cyclophilin D, the mitochondrial receptor for cyclosporin A, is present in pea stem mitochondria. These results indicate that the plant PT has unique features and suggest that, as in Drosophila, it may provide pea stem mitochondria with a Ca2+ release channel

Polyenylphosphatidylcholines as bioactive excipient in tablets for the treatment of liver fibrosis.

Liver fibrosis is a condition characterized by the accumulation of extracellular matrix (ECM) arising from the myofibroblastic transdifferentiation of hepatic stellate cells (HSCs) occurring as the natural response to liver damage. To date, no pharmacological treatments have been specifically approved for liver fibrosis. We recently reported a beneficial effect of polyenylphosphatidylcholines (PPCs)-rich formulations in reverting fibrogenic features of HSCs. However, unsaturated phospholipids' properties pose a constant challenge to the development of tablets as preferred patient-centric dosage form. Profiting from the advantageous physical properties of the PPCs-rich Soluthin® S 80 M, we developed a tablet formulation incorporating 70% w/w of this bioactive lipid. Tablets were characterized via X-ray powder diffraction, thermogravimetry, and Raman confocal imaging, and passed the major compendial requirements. To mimic physiological absorption after oral intake, phospholipids extracted from tablets were reconstituted as protein-free chylomicron (PFC)-like emulsions and tested on the fibrogenic human HSC line LX-2 and on primary cirrhotic rat hepatic stellate cells (PRHSC). Lipids extracted from tablets and reconstituted in buffer or as PFC-like emulsions exerted the same antifibrotic effect on both activated LX-2 and PRHSCs as observed with plain S 80 M liposomes, showing that the manufacturing process did not interfere with the bioactivity of PPCs

Celiac Disease Negatively Influences Lipid Profiles in Youngest Children With Type 1 Diabetes: Effect of the Gluten-Free Diet

The association between low HDL cholesterol (HDL-C) concentrations and increased cardiovascular risk is well established. Low HDL-C levels were found in subjects with type 1 diabetes (T1D) who presented complications and in untreated subjects with celiac disease (CD). The association between TID and CD might therefore enhance this lipid abnormality and accelerate the atherosclerotic process

The long Pentraxin 3 plays a role in bone turnover and repair

Pentraxin 3 (PTX3) is an inflammatory mediator acting as a fluid-phase pattern recognition molecule and playing an essential role in innate immunity and matrix remodeling. Inflammatory mediators also contribute to skeletal homeostasis, operating at multiple levels in physiological and pathological conditions. This study was designed to investigate the role of PTX3 in physiological skeletal remodeling and bone healing. Micro-computed tomography (μCT) and bone histomorphometry of distal femur showed that PTX3 gene-targeted female and male mice (ptx3−/−) had lower trabecular bone volume than their wild-type (ptx3+/+) littermates (BV/TV by μCT: 3.50 ± 1.31 vs 6.09 ± 1.17 for females, p < 0.0001; BV/TV 9.06 ± 1.89 vs 10.47 ± 1.97 for males, p = 0.0435). In addition, μCT revealed lower trabecular bone volume in second lumbar vertebra of ptx3−/− mice. PTX3 was increasingly expressed during osteoblast maturation in vitro and was able to reverse the negative effect of fibroblast growth factor 2 (FGF2) on osteoblast differentiation. This effect was specific for the N-terminal domain of PTX3 that contains the FGF2-binding site. By using the closed transversal tibial fracture model, we found that ptx3−/− female mice formed significantly less mineralized callus during the anabolic phase following fracture injury compared to ptx3+/+ mice (BV/TV 17.05 ± 4.59 vs 20.47 ± 3.32, p = 0.0195). Nonhematopoietic periosteal cells highly upregulated PTX3 expression during the initial phase of fracture healing, particularly CD51+ and αSma+ osteoprogenitor subsets, and callus tissue exhibited concomitant expression of PTX3 and FGF2 around the fracture site. Thus, PTX3 supports maintenance of the bone mass possibly by inhibiting FGF2 and its negative impact on bone formation. Moreover, PTX3 enables timely occurring sequence of callus mineralization after bone fracture injury. These results indicate that PTX3 plays an important role in bone homeostasis and in proper matrix mineralization during fracture repair, a reflection of the function of this molecule in tissue homeostasis and repair