Evidence for heme oxygenase-1 association with caveolin-1 and -2 in mouse mesangial cells

The interaction of heme oxygenase-1 (HO-1) and caveolin in the cultured mouse mesangial cells (MMC) was investigated. In normal MMCs, high levels of caveolin-2 and low level of caveolin-1 at mRNA and protein level were observed without any detectable expression of caveolin-3. Upon treating the MMCs either with cadmium (Cd) or spermine NONOate (SPER/NO), expression of HO-1 mRNA and protein was increased. Caveolae rich membranous fractions from the MMCs treated with Cd or SPER/NO contained both HO-1 and caveolin-1 or caveolin-2. The experiments of immuno-precipitation showed complex formation between the HO-1 and caveolin-1 or caveolin-2 in the Cd treated MMCs. Confocal microscopic results also support co-localization of HO-1 and caveolin-1 or caveolin-2 at the plasma membrane. Co-localization of caveolins with HO-1 in caveolae suggested that caveolin could also play an important role in regulating the function of HO-1.     

Fetal and maternal tissue distribution of the new fluoroquinolone DW-116 in pregnant rats

We investigated maternal and fetal tissue distribution of DW-116, a newly developed fluoroquinolone with a broad antibacterial spectrum against both G(+) and G(-) bacteria, in pregnant rats. After oral administration of [14C]-DW-116 (labeled 1 mg and unlabeled 500 mg/kg) to female rats on the 18th day of gestational, groups of three rats were killed at various time points up to 24 h, and plasma and tissues were collected, processed and analyzed. [14C]-DW-116 was rapidly absorbed, and distributed into the maternal and fetal tissues, and it declined in a biphasic manner with elimination half-lives (t(1/2)) of 10-15 h and mean residence times (MRT(0-24 h)) of 4-9 h. The radioactivity in most tissues of both dams and fetus reached its peak within 1 h and radioactivity levels of up to 10-25% of the peak level were maintained until 24 h after dosing. Among various tissues, the radioactivity in the maternal lungs was the highest (27 times that of plasma) at the C(max). Radioactivity in other tissues including liver, kidney, heart, lung, brain, spleen, mammary gland, placenta, ovary and uterus was higher than that in the maternal plasma (one- to three-fold). The tissue-to-plasma partition coefficient (K(p), AUC(0-24 h,tissue)/AUC(0-24 h,plasma)) of [14C]-DW-116 in maternal tissues was highest in the lung (K(p)=3.7), followed by the spleen (2.2), kidney (2.0), liver (1.8), heart (1.5), placenta (1.3), brain (1.3), ovary (1.1), uterus (1.1), and mammary gland (1.0). The tissue-to-plasma partition coefficient values in fetal tissues were heart (K(p)=2.2), kidney (2.1), liver (1.9), lung (1.6) and brain (1.4). When lactating rats were given a single oral dose of [14C]-DW-116, the radioactivity was rapidly secreted into the milk with K(p) of 1.7 at T(max) (0.5 h). These results indicate that DW-116 or its related metabolite(s) rapidly cross the blood-placenta and blood-milk barrier, extensively distribute into the fetal tissues, and are eliminated from the body in a prolonged manner. This study sheds insights into the maternal and fetal tissue distribution of DW-116 and will be useful for assessing both therapeutic and toxicological relevance of DW-116 in pregnant subjects.     

Measurement of protease activity of live Uronema marinun (Ciliata: Scuticociliatida) by fluorescence polarization

The proteolytic activity of live Uronema marinum was analyzed by a fluorescence polarization (FP) technique. Protease activity was measured as a decrease in the FP value using fluorescein isothiocynate (FITC)-casein as a protein substrate. A time-dependent decrease in FP occurred in plate wells containing live U. marinum. Supplementation with the cysteine protease inhibitor E-64 had no significant inhibitory effect on the decrease in FP at any of the concentrations used. In contrast, supplementation with 1,10-phenanthroline resulted in complete inhibition of proteolysis for 30 min at 1 mM and for 1 h at 2 and 5 mM. Effective inhibition of the proteolytic activity of live U. marinum by 1,10-phenanthroline indicated that metalloproteases are the main proteases excreted by U. marinum. As U. marinum has a high potential for systemically invading and destroying fish tissues, the metalloproteases excreted by live U. marinum are likely to be involved in the invasion of host tissues and the pathogenicity of the parasite.     

Microglial Phagocytosis of Dopamine Neurons at Early Phases of Apoptosis

Transection of the medial forebrain bundle caused apoptosis of dopamine neurons in the rat substantia nigra. Immunohistochemical localization of activated microglia and tyrosine hydroxylase in the axotomized substantia nigra showed that activation of microglia was rapid and OX-6 (MHC-II marker)-positive and ED1 (lysosomal phagocytic marker)-positive microglia were apposed to structurally intact tyrosine hydroxylase-positive dopamine neurons, indicating microglial phagocytosis of degenerating dopamine neurons. The occurrence of microglial phagocytosis at early stages of apoptosis may indicate the evolution of apoptosis into an irreversible state. Alternatively, interventions that suppress early activation of microglia might lead to novel mechanisms for neuron protection.     

(-)-hydroxycitrate ingestion increases fat oxidation during moderate intensity exercise in untrained men

We examined the effects of (-)-Hydroxycitrate (HCA) ingestion on fat oxidation during moderate intensity exercise in untrained men. Six subjects ingested 500 mg of HCA or a placebo for 5 days and did endurance exercise. Blood FFA concentrations were significantly increased and respiratory exchange ratio (RER) decreased by HCA ingestion. These results suggested short-term HCA ingestion increases fat oxidation in untrained men.     

Effect of dietary pectin on the production of immunoglobulins and cytokines by mesenteric lymph node lymphocytes in mouse colitis induced with dextran sulfate sodium

The present study explores the dietary effect of pectin on the MLN lymphocyte functions of mice with dextran sulfate sodium (DS)-induced colitis. We found that the immunoglobulin (Ig)A level in mesenteric lymph node (MLN) lymphocytes was high, while the IgE level was lower, in mice fed with pectin than in those fed with cellulose. Interestingly, the fecal IgA concentration of the pectin-fed mice was significantly higher than that of the cellulose-fed mice. The concentrations of interferon-gamma and interleukin (IL)-2 treated with concanavalin A (ConA) were significantly higher in the pectin-fed group than in the cellulose-fed group. Although dietary pectin did not affect the IL-4 and IL-10 levels, the activation-induced IL-4 and IL-10 secretion was lower in MLN cells of the pectin-fed mice than of the cellulose-fed mice following DS-induced colitis. Based on these findings, we propose that the effect of dietary pectin on mice with DS-induced colitis is mediated by the manipulation of Th1 cells. Furthermore, the inhibitory effect of IL-4 and IL-10 by dietary pectin may play an important role in promoting a change in Th1/Th2 balance toward Th1-dominant immunity.     

Effect of the flavonoid components obtained from Scutellaria radix on the histamine,immunoglobulin E and lipid peroxidation of spleen lymphocytes of Sprague-Dawley rats

The effect on the IgE content induced by concanavalin A in spleen lymphocytes of the presence wogonin, ganhuangenin, wogonoside and 3,5,7,2',6'-pentahydroxyl flavanone was investigated. These flavonoid components markedly inhibited the histamine released from cells stimulated with the calcium ionophore, A23187. However, the magnitude of the inhibitory effect on the degree of lipid peroxidation by ConA of these components was in order of PHF>GHG>WG>WGS. Interestingly, WG, GHG and WGS, with a methoxyl group in the A and B rings, strongly inhibited histamine and IgE production, whereas PHF without a methoxyl group was much stronger than that for lipid peroxidation. We suggest that WG, GHG and WGS might block the pathway for the release of histamine, and that the IgE level in spleen lymphocytes is responsible for the lipid peroxidation.     

Karyotypes of metaphase chromosomes in diploid populations of Dendranthema zawadskii and related species (Asteraceae) from Korea: diversity and evolutionary implications

Although the Dendranthema zawadskii complex has been known to comprise a series of polyploids (4x, 6x, 8x), we found diploid individuals (with 2 n=18) to occur in four populations of D. zawadskii var. latilobum in the southern region of Korea. Karyotypes of metaphase chromosomes were diverse because numbers of metacentric, submetacentric, and acrocentric chromosomes differ even within a population. A total of 17 karyotypes were found in 31 diploid individuals collected from the four populations. The karyotypes were also diverse in the presence or absence of chromosomes with a secondary constriction on a short or long arm and, if present, in the number of such chromosomes. They were further diverse in the presence or absence of non-homologous chromosome(s), the presence or absence of a chromosome with a satellite, and, if present, how many and where satellites are present. Almost the same pattern of diversity was found in diploid individuals (with 2 n=18) of D. boreale and D. indicum as well, irrespective of whether they occur together with D. zawadskii var. latilobum or not. Structural features of chromosomes in the variously different karyotypes suggest that reciprocal translocation and the hybridization between individuals with different karyotypes had repeatedly occurred not only in D. zawadskii var. latilobum, but also in D. boreale and D. indicum. Morphologically intermediate individuals between D. zawadskii var. latilobum and D. indicum suggests that the hybridization occur with different species as well.     

Effect of dietary fiber on the lipid metabolism and immune function of aged Sprague-Dawley rats

Eight-month-old Sprague-Dawley rats were fed on diets containing dietary fiber at the 5% level for 3 weeks to examine the effect on the lipid metabolism and immune function. Among cellulose, guar gum, partially hydrolyzed guar gum (PHGG), glucomannan and highly methoxylated pectin, guar gum induced a significant decrease in the food intake and weight gain, as well as a significant increase in the liver weight. In addition, the epidydimal adipose tissue weight of the rats fed on PHGG was significantly higher than that of the rats fed on cellulose. There was no significant effect on the serum lipid levels, but the serum IgG level of the rats fed on guar gum was significantly lower than that of the rats fed on cellulose. The IgA and IgG productivity in mesenteric lymph node (MLN) lymphocytes was significantly higher in the rats fed on guar gum, glucomannan and pectin than in those fed on cellulose, while the effect on Ig productivity in spleen lymphocytes was not as marked. In addition, only guar gum induced a significant increase of IgM productivity in MLN lymphocytes when compared to the cellulose group. These results suggest that enhancement of the immune function by dietary fiber is mainly expressed in the gut immune system.