ALDH1A3 Is the Key Isoform That Contributes to Aldehyde Dehydrogenase Activity and Affects <i>in Vitro</i> Proliferation in Cardiac Atrial Appendage Progenitor Cells.

High aldehyde dehydrogenase (ALDH &lt;sup&gt;hi&lt;/sup&gt; ) activity has been reported in normal and cancer stem cells. We and others have shown previously that human ALDH &lt;sup&gt;hi&lt;/sup&gt; cardiac atrial appendage cells are enriched with stem/progenitor cells. The role of ALDH in these cells is poorly understood but it may come down to the specific ALDH isoform(s) expressed. This study aimed to compare ALDH &lt;sup&gt;hi&lt;/sup&gt; and ALDH &lt;sup&gt;lo&lt;/sup&gt; atrial cells and to identify the isoform(s) that contribute to ALDH activity, and their functional role. &lt;b&gt;Methods and Results:&lt;/b&gt; Cells were isolated from atrial appendage specimens from patients with ischemic and/or valvular heart disease undergoing heart surgery. ALDH &lt;sup&gt;hi&lt;/sup&gt; activity assessed with the Aldefluor reagent coincided with primitive surface marker expression (CD34 &lt;sup&gt;+&lt;/sup&gt; ). Depending on their ALDH activity, RT-PCR analysis of ALDH &lt;sup&gt;hi&lt;/sup&gt; and ALDH &lt;sup&gt;lo&lt;/sup&gt; cells demonstrated a differential pattern of pluripotency genes (Oct 4, Nanog) and genes for more established cardiac lineages (Nkx2.5, Tbx5, Mef2c, GATA4). ALDH &lt;sup&gt;hi&lt;/sup&gt; cells, but not ALDH &lt;sup&gt;lo&lt;/sup&gt; cells, formed clones and were culture-expanded. When cultured under cardiac differentiation conditions, ALDH &lt;sup&gt;hi&lt;/sup&gt; cells gave rise to a higher number of cardiomyocytes compared with ALDH &lt;sup&gt;lo&lt;/sup&gt; cells. Among 19 ALDH isoforms known in human, ALDH1A3 was most highly expressed in ALDH &lt;sup&gt;hi&lt;/sup&gt; atrial cells. Knocking down ALDH1A3, but not ALDH1A1, ALDH1A2, ALDH2, ALDH4A1, or ALDH8A1 using siRNA decreased ALDH activity and cell proliferation in ALDH &lt;sup&gt;hi&lt;/sup&gt; cells. Conversely, overexpressing ALDH1A3 with a retroviral vector increased proliferation in ALDH &lt;sup&gt;lo&lt;/sup&gt; cells. &lt;b&gt;Conclusions:&lt;/b&gt; ALDH1A3 is the key isoform responsible for ALDH activity in ALDH &lt;sup&gt;hi&lt;/sup&gt; atrial appendage cells, which have a propensity to differentiate into cardiomyocytes. ALDH1A3 affects &lt;i&gt;in vitro&lt;/i&gt; proliferation of these cells

Health-related quality of life and functional changes in DMD: A 12-month longitudinal cohort study

In Duchenne muscular dystrophy (DMD) little has been reported on the association between clinical outcome measures and patient health-related quality of life (HRQOL) tools. Our study evaluated the relationship between 12 month changes on the Generic Core Scales (GCS), the Multidimensional Fatigue Scale and the Neuromuscular Module of the PedsQL\u2122 with several outcome measures (6 minute walk test, North Star Ambulatory Assessment and timed items) in ambulatory DMD. Ninety-eight ambulatory DMD in a multicentric setting were included in the study. At baseline, the PedsQL\u2122 inventories correlated with almost all the functional measures On the Child Self-Report there was a significant decrease between baseline and 12 months on the PedsQL\u2122 GCS and its first domain, in parallel with the decrement in the functional outcome measures. Correlation between the 12 month changes on the PedsQL\u2122 inventories and functional measures were almost all negligible. Similar results were obtained on the Parent Proxy-Report.In conclusion, PedsQL\u2122 correlates with the level of impairment at baseline, but this does not hold true when 12 month changes are considered. Further studies comparing different tools are needed to better elucidate the complexity of the relationship between HRQOL and functional performances

Antarctic fish hemoglobins: evidence of adaptive evolution at subzero temperature

Notothenioids represent a large group of marine teleosts that are mostly endemic to the Antarctic Ocean. In this environment, the low metabolic demand and the high oxygen concentration reduce the need for hemoglobin(s) [Hb(s)]. The extreme condition is represented by the icefish (Channichthyidae, Notothenioidei), the only vertebrates that lack Hb. We obtained the nucleotide sequence coding for the beta-globin chain of the single major Hb form in six red-blooded notothenioids. These included Gymnodraco acuticeps, one of the closest species to the Hb-less icefish, which is also the only known fish having a single Hb without Bohr effect. This species shows a higher rate of nonsynonymous substitutions (K-A), in contrast with the homogeneity of synonymous substitution (K-S) rates, and K-A/K-S ratios significantly greater than one in the majority of comparisons. These results are suggestive of positive selection, diversifying the single major Hb toward specialized functions. A single Hb that is free to diversify means that its role in routine oxygen transport can be reduced in the presence of a combination of physiological, ecological, and environmental factors. Although a reduced "routine" function for Hb, as is apparent in G. acuticeps, might, indeed, evoke the lack of Hb in icefish, evidence of diversifying selection reported here is at variance with the hypothesis of a simple trend from a single Hb toward the Hb-less condition

Data from: Mitochondrial phylogeny of notothenioids: a molecular approach to Antarctic fish evolution and biogeography

Antarctic waters represent a unique marine environment delimited by an oceanographic barrier, the Polar Front Zone, and characterized by constant subzero temperatures and presence of sea ice. A group of teleost fish, the Notothenioidei, have adapted to these challenging environmental conditions, undergoing a remarkable diversification. In the present study a total of 798 base pairs, generated from partial sequencing of 16S and 12S mitochondrial ribosomal RNA genes, were examined in 33 notothenioid species representative of all families included in the suborder Notothenioidei. Phylogenetic trees, reconstructed on the basis of sequence data using different methods, indicate that traditional hypotheses on notothenioid systematics and biogeography might be in need of reexamination. Molecular evidence suggests that vicariant speciation could be invoked to explain the early divergence of Eleginops maclovinus, a species previously included in the family Nototheniidae, which is now proposed as the closest sister group to all the rest of notothenioids apart from bovichtids. On the other hand, repeated, independent dispersal through the Polar Front is proposed for the divergence of other subantarctic notothenioid species. Likewise, multiple, independent transitions from benthic to pelagic habit are inferred from molecular data, at variance with the more conservative hypothesis based on cladograms reconstructed from morphological data

Mitochondrial phylogeny of notothenioids: A molecular approach to antarctic fish evolution and biogeography

Antarctic waters represent a unique marine environment delimited by an oceanographic barrier, the Polar Front Zone, and characterized by constant subzero temperatures and presence of sea ice. A group of teleost fish, the Notothenioidei, have adapted to these challenging environmental conditions, undergoing a remarkable diversification. In the present study a total of 798 base pairs, generated from partial sequencing of 16S and 12S mitochondrial ribosomal RNA genes, were examined in 33 notothenioid species representative of all families included in the suborder Notothenioidei. Phylogenetic trees, reconstructed on the basis of sequence data by different methods, indicate that traditional hypotheses on notothenioid systematics and biogeography might be in need of reexamination. Molecular evidence suggests that vicariant speciation could be invoked to explain the early divergence of Eleginops maclovinus, a species previously included in the family Nototheniidae, which is now proposed as the closest sister group to all the rest of notothenioids apart from bovichtids. On the other hand, repeated, independent dispersal through the Polar Front is proposed for the divergence of other subantarctic notothenioid species. Likewise, multiple, independent transitions from benthic to pelagic habit are inferred from molecular data, at variance with the more conservative hypothesis based on cladograms reconstructed from morphological data