Hoven's carp Leptobarbus hoevenii strategized metabolism needs to cope with changing environment.

Current water warming and freshwater acidification undoubtedly affect the life of aquatic animals especially ammonotelic teleost by altering their physiological responses. The effect of temperature (28 °C vs 32 °C) and pH (7 vs. 5) on the metabolic compromising strategies of Hoven's carp (Leptobarbus hoevenii) was investigated in this study. Fishes were conditioned to (i) 28 °C + pH 7 (N28°C); (ii) 32 °C + pH 7 (N32°C); (iii) 28 °C + pH 5 (L28°C) and (iv) 32 °C + pH 5 (L32°C) for 20 days followed by osmorespiration assay. Results showed that feeding performance of Hoven's carp was significantly depressed when exposed to low pH conditions (L28°C and L32°C). However, by exposed Hoven's carp to L32°C induced high metabolic oxygen intake and ammonia excretion to about 2x-folds higher compared to the control group. As for energy mobilization, Hoven's carp mobilized liver and muscle protein under L28°C condition. Whereas under high temperature in both pH, Hoven's carp had the tendency to reserve energy in both of liver and muscle. The findings of this study revealed that Hoven's carp is sensitive to lower water pH and high temperature, thereby they remodeled their physiological needs to cope with the environmental changes condition.

Gene Expression Analysis of CD34~+ Hematopoietic Stem and Progenitor Cells Grown in Different Culture Environments Using Differential Display / 中国生物工程杂志

Objective: To investigate the changes of gene expression in CD34+ hematopoietic stem and progenitor cells (HSPCs) under different growth environments. Methods: Umbilical cord blood mononuclear cells (UCB MNCs) were cultured in static and stirred systems. After 7 days of culture, CD34+ cells were isolated and total RNA was extracted. Gene expression patterns of CD34+ cells from fresh, static and stirred cultures were compared using differential display (DD). Results: 30 gene fragments displayed differential expression levels based on the conditions of DD. One of differentially expressed genes was identified as RAN, which is a member of oncogene RAS family. This gene may be associated with proliferation of hematopoietic cells. Conclusion: Different growth environments induced differential gene expression patterns of CD34+ HSPCs. These differentially expressed genes would give new insights into optimizing in vitro environments for expanding hematopoietic cells.