Lipogenic gene expression in abdominal adipose and liver tissues of diet-induced overweight cats

The effect of overweight status on the expression of SREBP-1c and downstream lipogenic genes, such as ATP citrate lyase (ACL) and fatty acid synthase (FAS), in abdominal adipose and liver tissues was determined in cats using a diet-induced weight gain model. ACL and SREBP-1c mRNA expression was significantly reduced (～65% and 20%, respectively) in liver tissue, whereas FAS and SREBP-1c expression was significantly increased (～80% and 45%, respectively) in abdominal omental adipose tissue of overweight animals as compared to healthy animals. Additionally, ACL, FAS, and SREBP-1c expression was significantly reduced by ～50%, 75%, and 70%, respectively, in abdominal subcutaneous adipose tissue of overweight animals. Omental adipose tissue appeared to foster, whereas subcutaneous adipose and liver tissues appeared to defer lipid storage based on differences in SREBP-1c mRNA expression. Overall, reduced lipogenic gene mRNA expression patterns support the hypothesis that SREBP-1c expression is reduced in overweight and possibly obese cats, reflecting down-regulation of the lipogenic pathway to prevent further fat accumulation and weight gain.     

Decreased gene expression of insulin signaling genes in insulin sensitive tissues of obese cats

Type 2 diabetes mellitus (DM) animal models have provided ample opportunity for investigating pathogenesis, as well as to evaluate novel treatment and prevention options for the disease. Because the domestic cat shares a similar environment with humans, it is also confronted with many similar risk factors for diabetes, such as physical inactivity and obesity. Obesity is a significant risk factor for diabetes in cats, and as such, the domestic cat may serve as an ideal model for investigating obesity induced insulin resistance. This study determined changes in insulin signaling genes within insulin sensitive tissues of obese felines. Quantitative RT-PCR was performed to determine mRNA levels of three important insulin signaling genes which have been implicated with insulin resistance: insulin receptor substrate (IRS)-1, IRS-2, and phosphatidylinositol 3’-kinase (PI3-K) p85α. Obese cats had significantly lower IRS-2 and PI3-K p85α mRNA levels in liver and skeletal muscle as compared to control cats. This down regulation of insulin signaling genes in obese cats mirrors that of obese humans and rodents suffering from insulin resistance. Interestingly, preprandial blood tests indicated that our obese cats were no different from control cats with regards to glucose tolerance and insulin resistance, thus indicating that the obese cats used in our study had a moderate level of obesity. Therefore, insulin signaling gene alterations were occurring in insulin sensitive tissues of moderately obese felines before glucose intolerance was clinically evident. As such, the monitoring of key insulin signaling genes may have some important diagnostic value to determine the risk level and degree of obesity induced insulin resistance.     

Developmental changes in structure and polypeptide profile of the androgenic gland of the freshwater prawn Macrobrachium rosenbergii

Although the mechanism of sex-differentiation in crustaceans has yet to be defined, the androgenic gland (AG) is thought to be the exclusive organ that produces the androgenic hormone (AH) which induces male sexual development. This paper presents results of light and transmission electron microscopy and total protein analysis of androgenic glands from three male morphotypes (orange-claw, orange-blue-claw and blue-claw) of the freshwater prawn, Macrobrachium rosenbergii. Highest protein content (76 µg//AG) was found in the blue-claw morphotype as compared to the orange-blue-claw (45 µg/AG) and the orange-claw morphotype (19 µg/AG). Sodiumdodecyl sulfate polyacrylamide gel electrophoresis (SDS-page) analysis of the cell free extract of the AG from the three morphotypes revealed four polypeptides (16, 18, 23 and 26 Kd) which quantitatively increase from the sexually immature orange-claw to the sexually mature blue-claw morphotype. The 16 and 18 Kd polypeptides could be the AHs.     

What is the optimal density of larval seeding in Acropora corals?

In situ larval seeding is a low-cost technique that is currently under development for the large-scale restoration of coral populations. One problem that still needs to be solved is the preparation of coral larvae for seeding, i.e., how many larvae are required to restore a certain area? In this study, we focused on the relationship between the numbers of larvae, settlers, and survivors for three?months post-settlement to determine the optimal larval seeding density. A comparison of three different larval densities (low, middle, and high) indicated that the number of settlers was proportional to the larval density, suggesting that settler density is determined by the number of larvae supplied. However, the survival rate of settlers on high-density plates was much lower than the corresponding rates on low- or middle-density plates during the first month after settlement. Moreover, most of the seeded corals had not survived on the low-density plates at three?months after settlement. Therefore, the middle larval density (i.e., 5000?larvae?m^?2) appears to be optimal for seeding on grid plates.     

Sperm Morphology Assessment in Captive Neotropical Primates

The main objective of this study was to evaluate sperm morphology in four neotropical primate species to compare the sperm morphological traits and the sperm morphometric parameters as a basis for establishing normative sperm standards for each species. Data from 80 ejaculates collected from four primate species, Callithrix jacchus, Callimico goeldii, Alouatta caraya and Ateles geoffroyi, were analysed for detection of sperm morphological alterations using subjective World Health Organization (WHO‐2010) standards and Sperm Deformity Index (SDI) criteria, objective computer‐assisted sperm morphometry analysis (CASMA) and subpopulation sperm determination (SSD) methods. There were multiple differences (p < 0.01) observed among primate species in values obtained from WHO‐2010, SDI, CASMA and SSD sperm analysis methods. In addition, multiple significant positive and negative correlations were observed between the sperm morphological traits (SDI, Sperm Deformity Index Head Defects, Sperm Deformity Index Midpiece Defects, Sperm Deformity Index Tail Defects, Normal Sperm, Head Defects, Midpiece Defects and Tail Defects) and the sperm morphometric parameters (SSD, Area (A), Perimeter (P), Length (L), Width (W), Ellipticity, Elongation and Rugosity) (p ≤ 0.046). In conclusion, our findings using different evaluation methods indicate that pronounced sperm morphological variation exists among these four neotropical primate species. Because of the strong relationship observed among morphological and morphometric parameters, these results suggest that application of objective analysis methods could substantially improve the reliability of comparative studies and help to establish valid normative sperm values for neotropical primates.     

Photochemical Formation of OH Radicals in Dew Formed on the Pine Needles at Mt. Gokurakuji

Photochemical formation rates and sources of the hydroxyl (OH) radical were determined in dew water formed on the surface of Japanese red pine (Pinus densiflora) needles of declining (NO₂ polluted area) and healthy pine stands at Mt. Gokurakuji located west of Hiroshima city in western Japan. The measured OH radical photoformation rates in dew water (n=10), which were normalized to the rate at midday on May 1 at 34°N, ranged from 0.67 to 5.18 µM h^?1 (1M=1mol L^?1). The mean value (2.69 µM h^?1) was higher than that in dew water collected on a Teflon board and higher than the mean value in rain water published previously. Of the total OH radical formation rate observed in dew water on the pine needles, 16.4 % was estimated to originate from N (III) (NO₂ ^? and HNO₂) and 24.6 % was estimated to originate from NO₃ ^?. There were other sources of OH radical photochemical formation in dew water on the pine needles besides photolysis of NO₂ ^? and NO₃ ^?.     

Aldehyde dehydrogenase activity in cancer stem cells from canine mammary carcinoma cell lines

Increasing evidence suggests that diverse solid tumours arise from a small population of cells known as cancer stem cells or tumour-initiating cells. Cancer stem cells in several solid tumours are enriched for aldehyde dehydrogenase (ALDH) activity. High levels of ALDH activity (ALDH(high)) were detected in four cell lines derived from canine mammary carcinomas. ALDH(high) cells were enriched in a CD44(+)CD24(-) population having self-renewal capacity. Xenotransplantation into immunodeficient mice demonstrated that 1×10(4) ALDH(high) cells were sufficient for tumour formation in all injected mice, whereas 1×10(4) ALDH(low) cells failed to initiate any tumours. ALDH(high)-derived tumours contained both ALDH(+) and ALDH(-) cells, indicating that these cells had cancer stem cell-like properties.     

Photochemical Formation of Hydroxyl Radicals in Red Soil-Polluted Seawater on the North of Okinawa Island, Japan

Land development has caused runoff of red soil into the ocean on the north side of Okinawa Island, Japan. In an attempt to clarify the impacts of this “red soil pollution” on the oxidizing power of seawater, we studied the formation of hydroxyl radical (?OH), the most potent oxidant in the environment, in red soil-polluted waters using a 313-nm monochromatic light. ?OH was photochemically formed in the red soil-polluted water samples, and the formation rates of ?OH decreased as salinity increased, i.e., as red soil-polluted river water gets mixed with seawater. The photo-formation rates of ?OH showed good correlations with dissolved Fe concentrations (R ²?=?0.96) and [NO₂ ^?]?+?[NO₃ ^?] concentrations (R ²?=?0.87), while a negative and weak correlation was found with dissolved organic carbon concentrations (R?=??0.78). Theoretical calculation showed that direct photolysis of NO₃ ^?, Fe(OH)²⁺, and hydrogen peroxide all together accounted for less than 10% of the observed ?OH formation in the red soil-polluted waters. Comparison between filtered and unfiltered samples showed that red soil particles were not the main sources of ?OH, and the photolysis of NO₂ ^? could account for at most 78% of the observed ?OH formation rates. We found that the Fenton’s reaction (a reaction between Fe(II) and H₂O₂) could possibly account for the observed formation of ?OH in the red soil-polluted waters.