AHR in energy balance regulation

Recent studies on mice genetically modified at the Ahr locus and fed on high-fat diet have revealed a novel physiological role for the AHR in energy balance. Globally impaired function of the receptor counteracts the development of obesity by increasing energy expenditure, which appears to occur mostly in the skeletal muscle and brown adipose tissue. On the other hand, global and tissue-specific loss of AHR signaling can have opposite effects on liver fat content and their impact on insulin sensitivity is also context-dependent. As tryptophan metabolites are key AHR activators, these findings suggest that the AHR may act as a protein sensor enabling adequate protein intake from low-protein diets by allowing calorie overfeeding without resultant obesity

Multigenerational and Transgenerational Effects of Dioxins

Dioxins are ubiquitous and persistent environmental contaminants whose background levels are still reason for concern. There is mounting evidence from both epidemiological and experimental studies that paternal exposure to the most potent congener of dioxins, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), can lower the male/female ratio of offspring. Moreover, in laboratory rodents and zebrafish, TCDD exposure of parent animals has been reported to result in reduced reproductive performance along with other adverse effects in subsequent generations, foremost through the paternal but also via the maternal germline. These impacts have been accompanied by epigenetic alterations in placenta and/or sperm cells, including changes in methylation patterns of imprinted genes. Here, we review recent key studies in this field with an attempt to provide an up-to-date picture of the present state of knowledge to the reader. These studies provide biological plausibility for the potential of dioxin exposure at a critical time-window to induce epigenetic alterations across multiple generations and the significance of aryl hydrocarbon receptor (AHR) in mediating these effects. Currently available data do not allow to accurately estimate the human health implications of these findings, although epidemiological evidence on lowered male/female ratio suggests that this effect may take place at realistic human exposure levels

Estrogenic Activities of Food Supplements and Beers as Assessed by a Yeast Bioreporter Assay

Mounting evidence of the effects of endocrine-disrupting chemicals (EDCs) in humans has led to assaying a vast array of food items (processed or packaged) as possible sources of human exposure to estrogens. In this study, we investigated the current situation in this respect of different food supplements and beer brands. Eleven food supplements and 24 beer brands were obtained from Helsinki, Finland. Sample preparation was carried out by established methods while estrogenic activities were assessed by a yeast bioluminescent assay, using two recombinant yeast strains (Saccharomyces cerevisiae BMAEREluc/ERα and S. cerevisiae BMA64/luc). All the food supplements as well as 81% of the beer samples tested were found to be estrogenic, with estradiol equivalent concentrations of food supplements and beer brands ranging from 7.5 to 11.5 µg/ml and from below detection limits to 43.6 ng/ml, respectively. The estrogenic activities detected in beer samples were not dependent on the beer's alcoholic content, the country of production, or the size of the production brewery. The results of our study imply that both food supplements and beers can be a significant source of human exposure to estrogens. Therefore, further studies and regular surveillance are warranted. © 2018, © 2018 Taylor & Francis Group, LLC.Peer reviewe

Pallean toimintahäiriö ja kuntoutus synnyttäneillä naisilla

Raskaus aiheuttaa merkittäviä fysiologisia ja rakenteellisia muutoksia naisen kehossa. Raskauden aikana pallean asento ja toiminta muuttuvat. Synnytyksen jälkeen muun muassa vauvan kantaminen ja imettäminen vaikuttavat kehon ja pallean asentoon ja siten myös hengitykseen. Mikäli pallea ja sen toiminta jätetään huomiotta synnytyksen jälkeisessä kuntoutuksessa, voi pallean toimintahäiriö ilmetä muun muassa erilaisina hengitystoiminnan häiriöinä tai kipuna kehon eri alueilla. Pallean toiminnan tutkimisen ja sen toimintahäiriön hoidon tulisikin aina kuulua synnytyksen jälkeiseen kuntoutukseen. Tämän opinnäytetyön tarkoituksena on lisätä synnyttäneiden naisten kanssa työskentelevien asiantuntijoiden tietoa ja käytännön taitoja liittyen pallean toimintaan, sen terveydellisiin vaikutuksiin sekä pallean toimintahäiriön kuntoutukseen. Tavoitteena on koota tuorein näyttöön perustuva tieto pallean toiminnasta, toimintahäiriöstä ja sen yleisimmistä ilmenemismuodoista sekä pallean toimintahäiriön kuntoutusmenetelmistä synnyttäneillä naisilla suomen kielellä. Aiheesta ei ole vielä julkaistu suomenkielistä materiaalia. Opinnäytetyön keskeisinä tuloksina lähteenä käytettyyn kirjallisuuteen perustuen pallean toimintahäiriön yleisimmät ilmenemismuodot synnyttäneillä naisilla ovat hyperventilaatio ja pinnallinen rintakehän yläosan hengitys. Opinnäytetyön lopussa on esitetty manuaalisia menetelmiä, Kinetic Control -testiliikkeitä, hengitysmetodeja sekä joogan asentoja pallean toiminnan tutkimiseen ja sen toimintahäiriön kuntoutukseen. Pallean toiminnan tutkimisen ja sen toimintahäiriön hoidon tulisi aina kuulua synnytyksen jälkeiseen kuntoutukseen. Opinnäytetyön toiminnallisena tuotoksena laaditaan koulutusmateriaali työpajan muodossa järjestettävään koulutuspäivään, joka toteutetaan työn tilaajan henkilökunnalle syksyllä 2018. Opinnäytetyön tilaaja on naisten terveyteen keskittyvä yritys FemiHealth Oy. Työn teoreettisen viitekehyksen muodostavat hengitys ja pallean toiminta, pallean toimintahäiriö, raskaus, synnytys ja synnytyksen jälkeinen vaihe sekä fysioterapia.Pregnancy causes significant physiological and structural changes in a woman’s body. During pregnancy, the position and function of the diaphragm changes. Postpartum, for example carrying and breastfeeding the baby affect the posture of the body and the diaphragm and thus breathing. If the diaphragm and its functions are ignored in postpartum rehabilitation, it may lead to diaphragmatic dysfunction manifesting itself in the form of a variety of breathing problems or pain in different parts of the body. Therefore, postpartum rehabilitation should always encompass the examination of diaphragmatic function and treatment of its possible dysfunction. The objective of this thesis is to increase the knowledge and practical skills of experts regarding the function of the diaphragm, its effects on health and the rehabilitation of diaphragmatic dysfunction in postpartum women. In addition, this thesis aspires to present in Finnish the most recent evidence-based knowledge of the function of the diaphragm, its dysfunction and the most common ways the dysfunction appears in postpartum women. Currently, no material about these subjects is available in Finnish. The key finding of this thesis, based on the literature used as reference, is that the most common manifestations of diaphragmatic dysfunction in postpartum women are hyperventilation and thoracic dominant breathing. Manual therapy approaches, Kinetic Control-based dissociation tests, breathing methods and yoga poses to aid in the examination and rehabilitation of diaphragmatic function are proposed at the end of this thesis. The practical product of this thesis is a training material for a training session to be organized in the form of a workshop for the working life partner of the thesis and its staff. The workshop will be organized in autumn 2018. The working life partner of the thesis is FemiHealth Oy, which is a company specializing in promoting women’s health. The theoretical framework of this thesis consists of breathing and the function of the diaphragm, diaphragmatic dysfunction, pregnancy, labour and postpartum phase, and physiotherapy

In vitro estrogenic, cytotoxic, and genotoxic profiles of the xenoestrogens 8-prenylnaringenine, genistein and tartrazine

Phytoestrogens have been widely praised for their health-promoting effects, whereas synthetic environmental estrogens are considered a toxicological risk to human health. The aim of this study was therefore to compare in vitro the estrogenic, cytotoxic, and genotoxic profiles of three common estrogen-like endocrine-disrupting chemicals: the phytoestrogens 8-prenylnaringenine (8-PN) and genistein and the synthetic xenoestrogen tartrazine. As assessed by a yeast bioreporter assay and estrogen-dependent proliferative response in human mammary gland adenocarcinoma cell line (MCF-7), 8-PN showed the highest estrogen-like activity of the three compounds, followed by tartrazine and genistein. After 24-h incubation on MCF-7 cells, all three compounds exhibited low cytotoxicity in the lactate dehydrogenase assay and no genotoxicity in the micronucleus assay. These results demonstrate that 8-PN, genistein and tartrazine possess variable estrogenic activity but display little cellular toxicity in short-term tests in vitro. No difference between phytoestrogens and a synthetic xenoestrogen could be established.Peer reviewe

Aryl hydrocarbon receptor agonists trigger avoidance of novel food in rats

The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor that mediates the toxicity of dioxins, but also plays important physiological roles, which are only beginning to unfold. Previous studies have surprisingly unveiled that low doses of the potent AHR agonist TCDD induce a strong and persistent avoidance of novel food items in rats. Here, we further examined the involvement of the AHR in the avoidance response in Sprague-Dawley rats with three established AHRagonists: 6-formylindolo(3,2-b)carbazole (FICZ), (beta-naphthoflavone (BNF) and benzo[a]pyrene (BaP); with a novel selective AHR modulator (C2); and with an activator of another nuclear receptor, CAR: 2,4,6-tryphenyldioxane-1,3 (TPD). As sensitive indices of AHR or CAR activity, we used Cypl al and Cyp2b1 gene expression, as they are, respectively, the drug-metabolizing enzymes specifically regulated by them. We further attempted to address the roles played by enhanced neophobia and conditioned taste aversion (CTA) in the avoidance behaviour. All AHR agonists triggered practically total avoidance of novel chocolate, but the durations varied. Likewise, acutely subtoxic doses of C2, differing by 25-fold, all elicited a similar outcome. In contrast, TPD did not influence chocolate consumption at all. If rats were initially accustomed to chocolate for 6 h after single FICZ or BNF exposure, avoidance was still clearly present two weeks later when chocolate was offered again. Hence, the avoidance response appears to specifically involve the AHR instead of being triggered by induction of intestinal or hepatic nuclear receptor signalling in general. It is also shared by both endogenous and exogenous AHR activators. Moreover, this behavioural change in rats seems to contain elements of both CTA and enhanced neophobia, but further clarification of this is still required. (C) 2016 Elsevier Inc. All rights reserved.Peer reviewe

The Potent Phytoestrogen 8-Prenylnaringenin: A Friend or a Foe?

8-prenylnaringenin (8-PN) is a prenylated flavonoid, occurring, in particular, in hop, but also in other plants. It has proven to be one of the most potent phytoestrogens in vitro known to date, and in the past 20 years, research has unveiled new effects triggered by it in biological systems. These findings have aroused the hopes, expectations, and enthusiasm of a “wonder-drug” for a host of human diseases. However, the majority of 8-PN effects require such high concentrations that they cannot be reached by normal dietary exposure, only pharmacologically; thus, adverse impacts may also emerge. Here, we provide a comprehensive and up-to-date review on this fascinating compound, with special reference to the range of beneficial and untoward health consequences that may ensue from exposure to it

The Potent Phytoestrogen 8-Prenylnaringenin: A Friend or a Foe?

8-prenylnaringenin (8-PN) is a prenylated flavonoid, occurring, in particular, in hop, but also in other plants. It has proven to be one of the most potent phytoestrogens in vitro known to date, and in the past 20 years, research has unveiled new effects triggered by it in biological systems. These findings have aroused the hopes, expectations, and enthusiasm of a “wonder-drug” for a host of human diseases. However, the majority of 8-PN effects require such high concentrations that they cannot be reached by normal dietary exposure, only pharmacologically; thus, adverse impacts may also emerge. Here, we provide a comprehensive and up-to-date review on this fascinating compound, with special reference to the range of beneficial and untoward health consequences that may ensue from exposure to it