Induction of GPR40 positively regulates cell motile and growth activities in breast cancer MCF-7 cells

Abstract

Free fatty acid (FFA) receptors belong to a member of G-protein-coupled receptors. GPCR 120 (GPR120) and GPR40 are identified as FFA receptors and activated via the binding of long- and medium-chain FFAs. The aim of this study was to assess the effects of GPR120 and GPR40 on cell motility and growth in breast cancer cells treated with tamoxifen (TAM). MCF-7 cells were continuously treated with TAM for approximately 6?months. The expression level of GPR40 gene was markedly higher in the long-term TAM treated (MCF-TAM) cells than in MCF-7 cells. In cell motility assay, MCF-TAM cells indicated the high cell motile activity, compared with MCF-7 cells. The cell motile activity of MCF-TAM cells was suppressed by a selective GPR40 antagonist, GW1100. To evaluate the effects of GPR40 on cell growth activity under estrogen-free conditions, cells were maintained in serum-free DMEM without phenol red for 2?days. In estrogen-free conditioned medium, the cell growth rate of MCF-TAM cells was significantly higher than that of MCF-7 cells. In addition, treatment of GW1100 reduced the cell growth rate of MCF-TAM cells. These results suggest that the cell motile and growth activities may be positively regulated through the induction of GPR40 by the long-term TAM treatment in MCF-7 cells.     

Infectivity of Cryptosporidium andersoni Kawatabi type relative to the small number of oocysts in immunodeficient and immunocompetent neonatal and adult mice

Cryptosporidium andersoni is a protozoan parasite found in many countries that invades the stomachs of primarily adult cattle. Unlike the isolates of C. andersoni in cattle from other countries, C. andersoni isolates from Japanese cattle can infect mice and were identified as a novel type and later defined as C. andersoni Kawatabi type. The biological characteristics of C. andersoni Kawatabi type have not yet been well documented. In the present study, we assess the infectivity of this type isolate in mice with different immune competence status and age. We found that inoculation of more than 1 × 10⁴ oocysts is needed to establish infection in mature mice irrespective of immune status. All of the infected immunocompetent mice recovered after a patent period of approximately 20 days. In immunodeficient mice, the pre-patent period was prolonged compared with that of 1 × 10⁶ oocysts, but the pattern and the maximum shedding measured by the number of oocysts per day were almost identical. In neonatal immunocompetent and immunodeficient mice, inoculation with 1 × 10⁴ to 10⁵ oocysts was also needed to establish infection. Our results indicate that there is a threshold of oocysts needed to establish patent infection in the acidic conditions of the stomach.     

The Prevalence and Characteristics of Metabolic Syndrome in Patients with Vertigo

Objectives/Hypothesis

Metabolic syndrome (MetS) is a condition that increases the risk of coronary artery disease and cerebral infarction. We determined the prevalence of MetS in vertigo patients and clinically investigated the association between MetS and vertigo.

Study Design

Case-control study

Methods

The subjects were 333 patients, including 107 males and 226 females, who presented with vertigo as a primary symptom. MetS was diagnosed according to the International Diabetes Federation definition, which is based on waist circumference, blood serum levels, and blood pressure.

Results

MetS was detected in 53 (15.9%) of 333 vertigo patients, including 24 males (22.4%) and 29 females (12.8%); i.e., the frequency of MetS was significantly higher among the male patients than the female patients. The overall prevalence of MetS (15.9%) among vertigo patients did not differ from that observed among general adults in previous Japanese surveillance studies; however, MetS was significantly more common among the vertigo patients in males than general adult males. The prevalence of MetS was also examined in five types of vertigo, Concomitant MetS was noted in many males with vertebrobasilar insufficiency (VBI) and isolated vertigo of unknown etiology.

Conclusion

It was suggested that MetS is involved in the development of vertigo in males. MetS might be a risk factor for vascular vertigo such as VBI in males. The high frequency of MetS among males with vertigo of unknown etiology suggested that the pathogenesis of metabolic syndrome is involved in this type of isolated vertigo.     

Ranging behavior of Mahale chimpanzees: a 16 year study

We have analyzed the ranging patterns of the Mimikire group (M group) of chimpanzees in the Mahale Mountains National Park, Tanzania. During 16 years, the chimpanzees moved over a total area of 25.2 or 27.4 km², as estimated by the grid-cell or minimum convex polygon (MCP) methods, respectively. Annually, the M group used an average of 18.4 km², or approximately 70 %, of the total home-range area. The chimpanzees had used 80 % of their total home range after 5 years and 95 % after 11 years. M group chimpanzees were observed more than half of the time in areas that composed only 15 % of their total home range. Thus, they typically moved over limited areas, visiting other parts of their range only occasionally. On average, the chimpanzees used 7.6 km² (in MCP) per month. Mean monthly range size was smallest at the end of the rainy season and largest at the end of the dry season, but there was much variability from year to year. The chimpanzees used many of the same areas every year when Saba comorensis fruits were abundant between August and January. In contrast, the chimpanzees used several different areas of their range in June. Here range overlap between years was relatively small. Over the 16 years of the study we found that the M group reduced their use of the northern part of their range and increased their frequency of visits to the eastern mountainous side of their home range. Changes in home-range size correlated positively with the number of adult females but not with the number of adult males. This finding does not support a prediction of the male-defended territory model proposed for some East African chimpanzee unit-groups.     

Comparative study of nutritional mode and mycorrhizal fungi in green and albino variants of Goodyera velutina,an orchid mainly utilizing saprotrophic rhizoctonia

The majority of chlorophyllous orchids form mycorrhizal associations with so‐called rhizoctonia fungi, a phylogenetically heterogeneous assemblage of predominantly saprotrophic fungi in Ceratobasidiaceae, Tulasnellaceae, and Serendipitaceae. It is still a matter of debate whether adult orchids mainly associated with rhizoctonia species are partially mycoheterotrophic. Here, we investigated the nutritional modes of green and albino variants of Goodyera velutina, an orchid species considered to be mainly associated with Ceratobasidium spp., by measuring their ¹³C and ¹⁵N abundances, and by molecular barcoding of their mycorrhizal fungi. Molecular analysis revealed that both green and albino variants of G. velutina harbored a similar range of mycobionts, mainly saprotrophic Ceratobasidium spp., Tulasnella spp., and ectomycorrhizal Russula spp. In addition, stable isotope analysis revealed that albino variants were significantly enriched in ¹³C but not so greatly in ¹⁵N, suggesting that saprotrophic Ceratobasidium spp. and Tulasnella spp. are their main carbon source. However, in green variants, ¹³C levels were depleted and those of ¹⁵N were indistinguishable from the co‐occurring autotrophic plants. Therefore, we concluded that the albino G. velutina variants are fully mycoheterotrophic plants whose C derives mainly from saprotrophic rhizoctonia, while the green G. velutina variants are mainly autotrophic plants, at least at our study site, in spite of their additional associations with ectomycorrhizal fungi. This is the first report demonstrating that adult nonphotosynthetic albino variants can obtain their nutrition mainly from nonectomycorrhizal rhizoctonia.     

Electrochemical screening of recombinant protein solubility in Escherichia coli using scanning electrochemical microscopy (SECM)

A microbial array chip with collagen gel spots entrapping living Escherichia coli (E. coli) DH5alpha was applied for the screening of recombinant protein solubilities. The alpha-fragment of beta-galactosidase (betaGal) was fused to the target protein, namely, maltose-binding protein (MBP), to monitor the solubility of MBP. Scanning electrochemical microscopy (SECM) was used to detect the release of p-aminophenol from E. coli cells catalyzed by intracellular betaGal. Comparison of the SECM-based method with the Western blotting-based method indicated that the current response obtained using SECM increased with an increase in the betaGal activity and therefore, with the soluble fraction of MBP in the host cells.     

Different effects of two exotic herbivores on the pollinator-mediated effect of an exotic plant on a native plant

Exotic plants can affect native plants indirectly through various biotic interactions. However, combinations of the multiple indirect effects of exotic plants on native plants have been rarely evaluated. Herbivory can either positively or negatively influence plant–pollinator interactions. Here, we addressed whether the pollinator-mediated plant interaction between exotic and native plants is altered through the introduction of exotic herbivores by conducting a 2-year common garden experiment. We compared the effects of pollinator-mediated indirect effects of an exotic plant, Solidago altissima, on the co-flowering native plant Aster microcephalus in geographically different populations reflecting differences in insect herbivore communities. We found a positive effect of co-flowering S. altissima on pollinator visitation of A. microcephalus, which varied between gardens and years. The co-flowering S. altissima did not significantly affect the seed set of A. microcephalus in the first year but had a negative effect in the second year. The facilitative effect of S. altissima on A. microcephalus pollination was suggested to be negatively affected by an exotic aphid, while it was not significantly affected by an exotic lace bug. Our study suggests that the phenology and feeding guilds of the herbivores may be critical for predicting the effect of exotic plants on native plants through herbivore–pollinator interactions. Integrated effects between plant interactions via multiple species interactions under different abiotic and biotic environments are necessary to understand the impact of exotic plants under complex interactions in nature.     

The speciation view: Disentangling multiple causes of adaptive and non-adaptive radiation in terms of speciation

Biological diversification often includes burst of lineage splitting. Such “radiation” has been known to act as evolutionary arenas with the potential to generate unique phylogenetic clusters and further novel groups. Although these radiations when accompanied by ecological diversification, so-called “adaptive radiation” have persisted as a central premise in evolutionary biology, the ecological and genetic mechanism of such rapid diversification has remained unclear. There are several critical definitions for the pattern of adaptive radiation, and those provide delimitation of adaptive and non-adaptive radiation. That being said, only a few studies have provided any clear demarcations in our understanding of the adaptive and non-adaptive causes of radiation from the mechanism of speciation. Here, we review the current consensus for the causes of adaptive radiation, especially along with the recent theoretical synthesis of “ecological speciation.” Further, we suggest the signature of adaptive and non-adaptive radiation in the earliest stages of diversification from the viewpoint of speciation. These criteria from the speciation view are useful to find the cases with the signatures of adaptive/non-adaptive radiation.     

Antipsychotic action of selective group II metabotropic glutamate receptor agonist MGS0008 and MGS0028 on conditioned avoidance responses in the rat

The present study was designed to investigate the antipsychotic-like effects of selective group II metabotropic glutamate receptor (mGluR) agonists, 5-[2-[4-(6-fluoro-1H-indole-3-yl) piperidin-1-yl]ethyl]-4-(4-fluorophenyl)thiazole-2-carboxylic acid amide (MGS0008) and (1R, 2S, 5S, 6S)-2-amino-6-fluoro-4-oxobicyclo[3.1.0]hexane-2,6-dicarboxylic acid monohydrate (MGS0028) on conditioned avoidance responses in rats. MGS0008 (1, 3 and 10 mg/kg, p.o.) and MGS0028 (0.3, 1 and 3 mg/kg, p.o.) significantly and reduced conditioned avoidance responses in a dose-dependent fashion. Similar effects were seen with LY418426 (0.3, 1 and 3 mg/kg, p.o.), but not with LY354740 (3, 10 and 30 mg/kg, p.o.), both of which are selective agonists for group II mGluR. Since this effect is seen with a wide range of antipsychotics, such as haloperidol and clozapine [Life Sciences 71 (2002) 947], group II mGluR agonists deserve further attention for possible antipsychotic activity.