Facklamia miroungae sp. nov., from a juvenile southern elephant seal (Mirounga leonina)

An unusual gram-positive, catalase-negative, facultatively anaerobic, coccus-shaped organism that originated from a juvenile elephant seal was characterized by phenotypic and molecular taxonomic methods. Comparative 16S rRNA gene sequencing showed that the unknown coccus represents a new subline within the genus Facklamia. The unknown strain was readily distinguishable from all currently recognized species of the genus Facklamia (Facklamia hominis, Facklamia languida, Facklamia ignava, Facklamia sourekii and Facklamia tabacinasalis) by biochemical tests and electrophoretic analysis of whole-cell proteins. Based on phylogenetic and phenotypic evidence, it is proposed that the unknown bacterium be classified as Facklamia miroungae sp. nov. The type strain of F. miroungae is CCUG 42728T (= CIP 106764T). F. miroungae is the first member of the genus Facklamia to be isolated from an animal other than man.

Differences in glucose-dependent insulinotropic polypeptide hormone and hepatic lipase in subjects of southern and northern Europe: implications for postprandial lipaemia

The aim was to determine in 32 healthy young men from northern and southern Europe whether differences in the secretion of insulin and glucose-dependent insulinotropic polypeptide (GIP) might explain these findings through the actions of these hormones on lipoprotein lipase. In a randomized, single-blind, crossover study the effects of 2 test meals of identical macronutrient composition but different saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) contents were investigated on postprandial GIP, insulin, the ratio of incremental triacylglycerol to apolipoprotein B-48 (a marker of chylomicron size), and the activity of postheparin lipases. Fasting and postprandial GIP concentrations and postheparin hepatic lipase (HL) activities were higher in the southern Europeans (P<0.001 and P<0.02, respectively). Lipoprotein lipase activity after the SFA-rich meal was higher in the northern Europeans (P<0.01). HL activity 9 h after the SFA-rich meal and the area under the curve (AUC) for the postprandial insulin response correlated with the AUC for the postprandial GIP response (r=0.44 (P<0.04) and r=0.46 (P<0.05), respectively). There were no significant differences in chylomicron size between the 2 groups for either meal, but when the groups were combined there was a difference in chylomicron size between the SFA- and MUFA-rich meals (P<0.05), which could be due to the formation of larger chylomicrons after the MUFA-rich meal. The significantly higher GIP and insulin responses and HL activities in southern Europeans may provide an explanation for a previous report of attenuated postprandial triacylglycerol and apolipoprotein B-48 responses in them.

Postprandial lipid and hormone responses to meals of varying fat contents: modulatory role of lipoprotein lipase?

OBJECTIVE: Substrate and hormone responses to meals of differing fat content were evaluated in normal subjects in order to investigate mechanisms underlying the regulation of postprandial lipoprotein concentration. DESIGN: A randomised cross-over study with three different meals on three occasions. SETTING: Free-living subjects associated with Surrey University. SUBJECTS: Ten male volunteers (aged 18-23 years) were recruited. INTERVENTIONS: Three test meals containing 20, 40 or 80 g fat but identical carbohydrate and protein content were randomly allocated to volunteers. MAJOR OUTCOME MEASURES: Pre- and postprandial blood samples were taken for the analysis of plasma triacylglycerol, non-esterified fatty acids, glucose, immunoreactive insulin and glucose-dependent insulinotrophic polypeptide levels and postheparin lipoprotein lipase activity measurements. RESULTS: Peak triacylglycerol concentrations and lipoprotein lipase activity measurements were significantly higher following the 80 g than the 20 g fat meal (P = 0.009 and P = 0.049 respectively). Areas under the glucose-dependent insulinotrophic polypeptide time-response concentration curves were significantly higher following the 80 g compared with the 20 g fat meal (P = 0.04), but no differences in insulin response to the meals were seen. The 30-360 min decrease in the non-esterified fatty acid concentration was less following the 80 g than the 20 g meal (P = 0.001). CONCLUSIONS: The results suggest that glucose-dependent insulinotrophic polypeptide may mediate increased lipoprotein lipase activity in response to fat-containing meals and may play a role in circulating lipoprotein homeostasis. This mechanism may be overloaded with high fat meals with adverse consequences on circulating triacylglycerol and NEFA concentrations.

The effect of triacylglycerol fatty acid positional distribution on postprandial plasma metabolite and hormone responses in normal adult men

The present study has examined the possibility that the positional distribution of fatty acids on dietary triacyglycerol (TAG) influences the postprandial response to a liquid meal in adult subjects. Postprandial TAG, non-esterified fatty acids (NEFA), ketones, glucose, insulin and gastric inhibitory polypeptide (GIP) responses were monitored in sixteen normal adult male subjects over 6 h following consumption of test meals containing dietary TAG in which palmitic acid was predominantly on the sn-1 (Control) or sn-2 positions (Betapol). Plasma total TAG, chylomicron-rich TAG and chylomicron-poor TAG concentrations were identical in response to the two test meals. The peak increase (mean (SD)) in chylomicron TAG was 0.85 (0.46) mmol/l after the Control meal and 0.85 (0.42) mmol/l after the Betapol meal. Plasma glucose, insulin, GIP, NEFA and ketone concentrations were also very similar following the two meals. It is concluded that dietary TAG containing saturated fatty acids on the sn-2 position appear in plasma at a similar level and over a similar timescale to TAG in which saturated fatty acids are predominantly located on sn-1 or sn-3 positions. The results reported in the present study demonstrate that the positional distribution of fatty acids on dietary TAG is not an important determinant of postprandial lipaemia in adult male subjects, but do not exclude the possibility that different responses may occur when these dietary TAG are given long term.

Effects of n-3 fatty acids on postprandial triacylglycerol and hormone concentrations in normal subjects

The present study reports results from two investigations to determine effects of a 6-week period of moderate n-3 fatty acid supplementation (2.7 g/d) on fasting and on postprandial triacylglycerol and metabolic hormone concentrations in response to standard test meals. In the first study postprandial responses were followed for 210 min after an early morning test meal challenge; in the second study responses to an evening test meal were followed during the evening and overnight for a total period of 12 h. In both studies postprandial triacylglycerol responses to the test meals were significantly reduced after compared with before fish-oil supplementation. In the second study the triacylglycerol peak response seen between 200 and 400 min in subjects studied before supplementation with fish oils was almost completely absent in the same subjects after 6 weeks of n-3 fatty acid supplementation. Analysis of fasting concentrations of metabolites and hormones was carried out on the combined data from the two studies. There were no significant differences in total, low-density-lipoprotein- or high-density-lipoprotein-cholesterol concentrations during fish-oil supplementation, although there was considerable individual variation in cholesterol responses to the supplement. Concentrations of Apo-B and Apo-A1 were unchanged during supplementation with fish oils. Fasting and early morning postprandial GIP concentrations were lower in subjects taking fish oils, possibly due to acute effects of fish-oil capsules taken on the evening before the studies. In both studies fasting insulin and glucose and postprandial insulin concentrations remained unchanged following fish-oil supplementation. The results do not support the view that triacylglycerol-lowering effects of n-3 fatty acids are due to modulation of insulin secretion mediated via the enteroinsular axis. Further studies are required to determine the precise mechanism by which fish oils reduce both fasting and postprandial triacylglycerol concentrations.

Thermogenic and metabolic consequences of thyroid hormone treatment in brown and white adipose tissue

Male rats were treated with triiodothyronine in the drinking water for 12 days. In vitro rates of isoprenaline stimulated lipolysis were significantly greater in brown but not white adipose tissue. Rates of [14C]glucose incorporation into triacylglycerols were significantly reduced in BAT (brown adipose tissue) and WAT (white adipose tissue) under basal and isoprenaline stimulated conditions. In a second experiment, hyperthyroid animals showed impaired weight gain, despite increased food intake during 19 days' treatment. Energy expenditure on days 5 and 12, and BAT core temperature differences (TBAT - TCORE) on day 19, were significantly greater than in control animals. Epididymal white fat pad weight was reduced and interscapular brown fat pad weight increased by triiodothyronine treatment.

Polymer therapeutics designed for a combination therapy of hormone-dependent cancer

Designer drug: A polymer therapeutic was designed for a combination therapy of breast cancer. N-(2-Hydroxypropyl)methacrylamide was used as the model polymer platform to prepare a unimolecular polymer conjugate (see picture, radius of gyration: 12.8 nm) that combines an endocrine (the aromatase inhibitor aminoglutethimide, blue) and a chemotherapeutic agent (the anthraxcycline antibiotic doxorubicin, red).

The global effect of follicle-stimulating hormone and tumour necrosis factor α on gene expression in cultured bovine ovarian granulosa cells

Background Oocytes mature in ovarian follicles surrounded by granulosa cells. During follicle growth, granulosa cells replicate and secrete hormones, particularly steroids close to ovulation. However, most follicles cease growing and undergo atresia or regression instead of ovulating. To investigate the effects of stimulatory (follicle-stimulating hormone; FSH) and inhibitory (tumour necrosis factor alpha; TNFα) factors on the granulosa cell transcriptome, bovine ovaries were obtained from a local abattoir and pools of granulosa cells were cultured in vitro for six days under defined serum-free conditions with treatments present on days 3–6. Initially dose–response experiments (n = 4) were performed to determine the optimal concentrations of FSH (0.33 ng/ml) and TNFα (10 ng/ml) to be used for the microarray experiments. For array experiments cells were cultured under control conditions, with FSH, with TNFα, or with FSH plus TNFα (n = 4 per group) and RNA was harvested for microarray analyses. Results Statistical analysis showed primary clustering of the arrays into two groups, control/FSH and TNFα/TNFα plus FSH. The effect of TNFα on gene expression dominated that of FSH, with substantially more genes differentially regulated, and the pathways and genes regulated by TNFα being similar to those of FSH plus TNFα treatment. TNFα treatment reduced the endocrine activity of granulosa cells with reductions in expression of FST, INHA, INBA and AMH. The top-ranked canonical pathways and GO biological terms for the TNFα treatments included antigen presentation, inflammatory response and other pathways indicative of innate immune function and fibrosis. The two most significant networks also reflect this, containing molecules which are present in the canonical pathways of hepatic fibrosis/hepatic stellate cell activation and transforming growth factor β signalling, and these were up regulated. Upstream regulator analyses also predicted TNF, interferons γ and β1 and interleukin 1β. Conclusions In vitro, the transcriptome of granulosa cells responded minimally to FSH compared with the response to TNFα. The response to TNFα indicated an active process akin to tissue remodelling as would occur upon atresia. Additionally there was reduction in endocrine function and induction of an inflammatory response to TNFα that displays features similar to immune cells.

How body mass and lifestyle affect juvenile biomass production in placental mammals

In mammals, the mass-specific rate of biomass production during gestation and lactation, here called maternal productivity, has been shown to vary with body size and lifestyle. Metabolic theory predicts that post-weaning growth of offspring, here termed juvenile productivity, should be higher than maternal productivity, and juveniles of smaller species should be more productive than those of larger species. Furthermore because juveniles generally have similar lifestyles to their mothers, across species juvenile and maternal productivities should be correlated. We evaluated these predictions with data from 270 species of placental mammals in 14 taxonomic/lifestyle groups. All three predictions were supported. Lagomorphs, perissodactyls and artiodactyls were very productive both as juveniles and as mothers as expected from the abundance and reliability of their foods. Primates and bats were unproductive as juveniles and as mothers, as expected as an indirect consequence of their low predation risk and consequent low mortality. Our results point the way to a mechanistic explanation for the suite of correlated life-history traits that has been called the slow–fast continuum.

Pippi Longstocking, juvenile delinquent? Hachette, self-censorship and the moral reconstruction of postwar France

This paper looks at the blockages to the publication of children’s literature caused by the intellectual climate of the postwar era, through a case study of the editorial policy of Hachette, the largest publisher for children at this time. This period witnessed heightened tensions surrounding the social and humanitarian responsibilities of literature. Writers were blamed for having created a culture of defeatism, and collaborationist authors were punished harshly in the purges. In the case of children’s literature, the discourse on responsibility was made more urgent by the assumption that children were easily influenced by their reading material, and by the centrality of the young to the discourse on the moral reconstruction of France. As the politician and education reformer Gustave Monod put it: “penser l’avenir, c’est penser le sort des enfants et de la jeunesse.” These concerns led to the expansion of associations and publications dedicated to protecting children and promoting “good” reading matter for them, and, famously, to the 1949 law regulating publications for children, which banned the depiction of crime, debauchery and violence that might demoralise young readers. Using the testimonials of former employees, along with readers’ reports and editorial correspondence preserved in the Hachette archives, this paper will examine how individual editorial decisions and self-censorship strategies were shaped by the 1949 law with its attendant discourse of moral panic on children’s reading, and how national concerns for future citizens were balanced with commercial imperatives.

Differential interaction of estrogen receptor and thyroid hormone receptor isoforms on the rat oxytocin receptor promoter leads to differences in transcriptional regulation

Both the estrogen receptor (ER) and thyroid hormone receptor (TR) are members of the nuclear receptor superfamily. Two isoforms of the ER, alpha and beta, exist. The TRalpha and beta isoforms are products of two distinct genes that are further differentially spliced to give TRalpha1 and alpha2, TRbeta1 and beta2. The TRs have been shown to interfere with ER-mediated transcription from both the consensus estrogen response element (ERE) and the rat preproenkephalin (PPE) promoter, possibly by competing with ER binding to the ERE or by squelching coactivators essential for ER-mediated transcription. The rat oxytocin receptor (OTR) gene is thought to be involved in several facets of reproductive and affiliative behaviors. 17beta-Estradiol-bound ERs upregulate the OTR gene in the ventromedial hypothalamus, a region critical for the induction of lordosis behavior in several species. We investigated the effects of the ligand-binding TR isoforms on the ER-mediated transcription from a physiological promoter of a behaviorally relevant gene such as the OTR. Only ERalpha could induce the OTR gene in two cell lines tested, the CV-1 and the SK-N-BE2C neuroblastoma cell lines. ERbeta was incapable of inducing the gene in either cell line. ERalpha is therefore not equivalent to ERbeta on this physiological promoter. Indeed, in the neural cell line, ERbeta can inhibit ERalpha-mediated induction from the OTR promoter. While the TRalpha1 isoform inhibited ERalpha-mediated induction in the neural cell line, the TRbeta1 isoform stimulated induction, thus demonstrating isoform specificity in the interaction. The use of a DNA-binding mutant, the TR P box mutant, showed that inhibition of ERalpha-mediated induction of the rat OTR gene promoter by the TRalpha1 isoform does not require DNA-binding ability. SRC-1 overexpression relieved TRalpha1-mediated inhibition in both cell lines, suggesting that squelching for coactivators is an important molecular mechanism in TRalpha-mediated inhibition. Such interactions between TR and ER isoforms on the rat OTR promoter provide a mechanism to achieve neuroendocrine integration.

Differential crosstalk between estrogen receptor (ER) alpha and ER beta and the thyroid hormone receptor isoforms results in flexible regulation of the consensus ERE

Crosstalk between nuclear receptors is important for conversion of external and internal stimuli to a physiologically meaningful response by cells. Previous studies from this laboratory have demonstrated crosstalk between the estrogen (ER) and thyroid hormone receptors (TR) on two estrogen responsive physiological promoters, the preproenkephalin and oxytocin receptor gene promoter. Since ERa and ERb are isoforms possessing overlapping and distinct transactivation properties, we hypothesized that the interaction of ERa and b with the various TR isoforms would not be equivalent. To explore this hypothesis, the consensus estrogen response element (ERE)derived from the Xenopus vitellogenin gene is used to investigate the differences in interaction between ERa and b isoforms and the different TR isoforms in fibroblast cells. Both the ER isoforms transactivate from the consensus ERE, though ERa transactivates to a greater extent than ERb. Although neither of the TRb isoforms have an effect on ERa transactivation from the consensus ERE, the liganded TRa1 inhibits the ERa transactivation from the consensus ERE. In contrast, the liganded TRa1 facilitates ERb-mediated transactivation. The crosstalk between the TRb isoforms with the ERa isoform, on the consensus ERE, is different from that with the ERb isoform. The use of a TRa1 mutant, which is unable to bind DNA, abolishes the ability of the TRa1 isoform to interact with either of the ER isoforms. These differences in nuclear receptor crosstalk reveal an important functional difference between isoforms, which provides a novel mechanism for neuroendocrine integration.

Crosstalk between oestrogen receptors and thyroid hormone receptor isoforms results in differential regulation of the preproenkephalin gene

Nuclear receptors are ligand-activated transcription factors, which have the potential to integrate internal metabolic events in an organism, with consequences for control of behaviour. Previous studies from this laboratory have shown that thyroid hormone receptor (TR) isoforms can inhibit oestrogen receptor (ER)alpha-mediated induction of preproenkephalin (PPE) gene expression in the hypothalamus. Also, thyroid hormone administration inhibits lordosis, a behaviour facilitated by PPE expression. We have examined the effect of multiple ligand-binding TR isoforms on the ER-mediated induction of the PPE gene in transient transfection assays in CV-1 cells. On a natural PPE gene promoter fragment containing two putative oestrogen response elements (EREs), both ER alpha and beta isoforms mediate a four to five-fold induction by oestrogen. Cotransfection of TR alpha 1 along with ER alpha inhibited the ER alpha transactivation of PPE by approximately 50%. However, cotransfection with either TR beta 1 or TR beta 2 expression plasmids produced no effect on the ER alpha or ER beta mediated induction of PPE. Therefore, under these experimental conditions, interactions with a single ER isoform are specific to an individual TR isoform. Transfection with a TR alpha 1 DNA-binding mutant could also inhibit ER alpha transactivation, suggesting that competition for binding on the ERE may not be the exclusive mechanism for inhibition. Data with the coactivator, SRC-1, suggested that coactivator squelching may participate in the inhibition. In dramatic contrast, when ER beta is cotransfected, TR alpha 1 stimulated ER beta-mediated transactivation of PPE by approximately eight-fold over control levels. This is the first study revealing specific interactions among nuclear receptor isoforms on a neuroendocrine promoter. These data also suggest that the combinatorics of ER and TR isoforms allow multiple forms of flexible gene regulations in the service of neuroendocrine integration.

Isoform specificity for oestrogen receptor and thyroid hormone receptor genes and their interactions on the NR2D gene promoter

Oestrogens are critical for the display of lordosis behaviour and, in recent years, have also been shown to be involved in synaptic plasticity. In the brain, the regulation of ionotropic glutamate receptors has consequences for excitatory neurotransmission. Oestrogen regulation of the N-methyl-d-aspartate receptor subunit 2D (NR2D) has generated considerable interest as a possible molecular mechanism by which synaptic plasticity can be modulated. Since more than one isoform of the oestrogen receptor (ER) exists in mammals, it is possible that oestrogen regulation via the ERalpha and ERbeta isoforms on the NR2D oestrogen response element (ERE) is not equivalent. In the kidney fibroblast (CV1) cell line, we show that in response to 17beta-oestradiol, only ERalpha, not ERbeta, could upregulate transcription from the ERE which is in the 3' untranslated region of the NR2D gene. When this ERE is in the 5' position, neither ERalpha nor ERbeta showed transactivation capacity. Thyroid hormone receptor (TR) modulation of ER mediated induction has been shown for other ER target genes, such as the preproenkephalin and oxytocin receptor genes. Since the various TR isoforms exhibit distinct roles, we hypothesized that TR modulation of ER induction may also be isoform specific. This is indeed the case. The TRalpha1 isoform stimulated ERalpha mediated induction from the 3'-ERE whereas the TRbeta1 isoform inhibited this induction. This study shows that isoforms of both the ER and TR have different transactivation properties. Such flexible regulation and crosstalk by nuclear receptor isoforms leads to different transcriptional outcomes and the combinatorial logic may aid neuroendocrine integration.