Heparin enhances the effects of mesenchymal stem cell transplantation in a rabbit model of acute myocardial infarction

Stem cell transplantation in combination with administration of bioactive compounds has shown promising results in treating myocardial infraction (MI). In the current study, we investigated the effect of combining mesenchymal stem cells (MSCs) transplantation with heparin into the infarcted heart rabbits. For this purpose, 35 male New Zealand white rabbits were randomly divided into five groups: sham, MI, MI+ MSCs, MI+ heparin and MI+MSCs+ heparin. MI was induced by 30 min ligation of the left anterior descending coronary artery. The animals of MSCs and MSCs +heparin groups were injected cell culture containing MSCs intramyocardially into the infarct area. Functional parameters of the left ventricle by echocardiography, serum levels of VEGF by enzyme-linked immunosorbent assay, size of fibrotic area by Masson's trichrome staining, evaluation of morphology by Haematoxylin-Eosin and capillary density alkaline phosphatase staining were compared between groups. Ejection fraction, fractional shortening and levels of VEGF significantly improved in MSCs and MSCs + heparin group (P < 0.05). The fibrotic area was significantly reduced (p=0.009) in MSC + heparin treated animals in comparison with MSCs. Number of live cells and angiogenesis were increased significantly in MSCs + heparin groups in comparison with MSCs (p < 0.05). Although injection of MSCs significantly restored normal function of fibrotic area, we found that administration of heparin combined with MSCs to infarcted heart of animals could have better effects on LV functional parameters in fibrosis area and resulted in superior therapeutic outcome in enhancing neovascularization and improving cardiac fibrosis. © Physiological Society of Nigeria

COMPLEX EVOLUTIONARY TRANSITIONS AND THE SIGNIFICANCE OF C3-C4 INTERMEDIATE FORMS OF PHOTOSYNTHESIS IN MOLLUGINACEAE:EVOLUTION OF C4 PHOTOSYNTHESIS IN MOLLUGINACEAE

C4 photosynthesis is a series of biochemical and structural modifications to C3 photosynthesis that has evolved numerous times in flowering plants, despite requiring modification of up to hundreds of genes. To study the origin of C4 photosynthesis, we reconstructed and dated the phylogeny of Molluginaceae, and identified C4 taxa in the family. Two C4 species, and three clades with traits intermediate between C3 and C4 plants were observed in Molluginaceae. C3–C4 intermediacy evolved at least twice, and in at least one lineage was maintained for several million years. Analyses of the genes for phosphoenolpyruvate carboxylase, a key C4 enzyme, indicate two independent origins of fully developed C4 photosynthesis in the past 10 million years, both within what was previously classified as a single species, Mollugo cerviana. The propensity of Molluginaceae to evolve C3–C4 and C4 photosynthesis is likely due to several traits that acted as developmental enablers. Enlarged bundle sheath cells predisposed some lineages for the evolution of C3–C4 intermediacy and the C4 biochemistry emerged via co-option of photorespiratory recycling in C3–C4 intermediates. These evolutionarily stable transitional stages likely increased the evolvability of C4 photosynthesis under selection environments brought on by climate and atmospheric change in recent geological time

Light Microscopy, Transmission Electron Microscopy, and Immunohistochemistry Protocols for Studying Photorespiration

High-resolution images obtained from plant tissues processed for light microscopy, transmission electron microscopy, and immunohistochemistry have provided crucial links between plant subcellular structure and physiology during photorespiration as well as the impact of photorespiration on plant evolution and development. This chapter presents established protocols to guide researchers in the preparation of plant tissues for high-resolution imaging with a light and transmission electron microscope and detection of proteins using immunohistochemistry. Discussion of concepts and theory behind each step in the process from tissue preservation to staining of resin-embedded tissues is included to enhance the understanding of all steps in the procedure. We also include a brief protocol for quantification of cellular parameters from high-resolution images to help researchers rigorously test hypotheses

Creating Leaf Cell Suspensions for Characterization of Mesophyll and Bundle Sheath Cellular Features

Imaging of mesophyll cell suspensions prepared from Arabidopsis has been pivotal for forming our current understanding of the molecular control of chloroplast division over the past 25 years. In this chapter, we provide a method for the preparation of leaf cell suspensions that improves upon a previous method by optimizing cellular preservation and cell separation. This technique is accessible to all researchers and amenable for use with all plant species. The leaf suspensions can be used for imaging chloroplast features within a cell that are important for photosynthesis such as size, number, and distribution. However, we also provide examples to illustrate how the cells in the suspensions can be easily stained to image other features, for example pit fields where plasmodesmata are located and organelles such as mitochondria, to improve our understanding of traits that are important for photosynthetic physiology

Data from: C4 anatomy can evolve via a single developmental change

C4 photosynthesis boosts productivity in warm environments. Paradoxically, this complex physiological process evolved independently in numerous plant lineages, despite requiring specialized leaf anatomy. The anatomical modifications underlying C4 evolution have previously been evaluated through interspecific comparisons, which capture numerous changes besides those needed for C4 functionality. Here, we quantify the anatomical changes accompanying the transition between non-C4 and C4 phenotypes by sampling widely across the continuum of leaf anatomical traits in the grass Alloteropsis semialata. Within this species, the only trait that is shared and specific to C4 individuals is an increase in vein density, driven specifically by minor vein development. The minor veins are genetically determined, and their multiple effects facilitate C4 function. For species with the necessary anatomical preconditions, developmental proliferation of veins can therefore be sufficient to produce a functional C4 leaf anatomy, creating an evolutionary entry point to complex C4 syndromes that can become more specialized

Targeted Knockdown of GDCH in Rice Leads to a Photorespiratory-Deficient Phenotype Useful as a Building Block for C4 Rice

The glycine decarboxylase complex (GDC) plays a critical role in the photorespiratory C2 cycle of C3 species by recovering carbon following the oxygenation reaction of ribulose-1,5-bisphosphate carboxylase/oxygenase. Loss of GDC from mesophyll cells (MCs) is considered a key early step in the evolution of C4 photosynthesis. To assess the impact of preferentially reducing GDC in rice MCs, we decreased the abundance of OsGDCH (Os10g37180) using an artificial microRNA (amiRNA) driven by a promoter that preferentially drives expression in MCs. GDC H- and P-proteins were undetectable in leaves of gdch lines. Plants exhibited a photorespiratory-deficient phenotype with stunted growth, accelerated leaf senescence, reduced chlorophyll, soluble protein and sugars, and increased glycine accumulation in leaves. Gas exchange measurements indicated an impaired ability to regenerate ribulose 1,5-bisphosphate in photorespiratory conditions. In addition, MCs of gdch lines exhibited a significant reduction in chloroplast area and coverage of the cell wall when grown in air, traits that occur during the later stages of C4 evolution. The presence of these two traits important for C4 photosynthesis and the non-lethal, down-regulation of the photorespiratory C2 cycle positively contribute to efforts to produce a C4 rice prototype