scholarly journals Disruption of female reproductive function by endotoxins

Reproduction ◽  
2018 ◽  
Vol 155 (4) ◽  
pp. R169-R181 ◽  
Author(s):  
K L Bidne ◽  
M J Dickson ◽  
J W Ross ◽  
L H Baumgard ◽  
A F Keating
Keyword(s):  
Intestinal Barrier ◽  
Reproductive Function ◽  
Chemical Exposure ◽  
Female Reproduction ◽  
Environmental Chemical ◽  
Luteal Function ◽  
Abiotic Stressors ◽  
Negative Impacts ◽  
Meiotic Competence ◽  
Metabolic Endotoxemia

Endotoxemia can be caused by obesity, environmental chemical exposure, abiotic stressors and bacterial infection. Circumstances that deleteriously impact intestinal barrier integrity can induce endotoxemia, and controlled experiments have identified negative impacts of lipopolysaccharide (LPS; an endotoxin mimetic) on folliculogenesis, puberty onset, estrus behavior, ovulation, meiotic competence, luteal function and ovarian steroidogenesis. In addition, neonatal LPS exposures have transgenerational female reproductive impacts, raising concern about early life contacts to this endogenous reproductive toxicant. Aims of this review are to identify physiological stressors causing endotoxemia, to highlight potential mechanism(s) by which LPS compromises female reproduction and identify knowledge gaps regarding how acute and/or metabolic endotoxemia influence(s) female reproduction.

scholarly journals The Influence of Gut Microbiota on the Cardiovascular System Under Conditions of Obesity and Chronic Stress

2021 ◽  
Vol 23 (5) ◽  
Author(s):  
Piotr Dubinski ◽  
Katarzyna Czarzasta ◽  
Agnieszka Cudnoch-Jedrzejewska
Keyword(s):  
Gut Microbiota ◽  
Cardiovascular System ◽  
Chronic Stress ◽  
Human Body ◽  
High Fat Diet ◽  
Intestinal Barrier ◽  
Microbial Composition ◽  
Enhanced Absorption ◽  
Bacterial Accumulation ◽  
Metabolic Endotoxemia

Abstract Purpose of Review Based on the available data, it can be assumed that microbiota is an integral part of the human body. The most heavily colonized area of the human body is the gut, with bacterial accumulation ranging from 101–103 cells/g in the upper intestine to 1011–1012 cells/g in the colon. However, colonization of the gut is not the same throughout, as it was shown that there are differences between the composition of the microbiota in the intestine lumen and in the proximity of the mucus layer. Recent Findings Gut microbiota gradient can be differentially regulated by factors such as obesity and chronic stress. In particular, a high fat diet influences the gut microbial composition. It was also found that chronic stress may cause the development of obesity and thus change the organization of the intestinal barrier. Recent research has shown the significant effect of intestinal microflora on cardiovascular function. Enhanced absorption of bacterial fragments, such as lipopolysaccharide (LPS), promotes the onset of “metabolic endotoxemia,” which could activate toll-like receptors, which mediates an inflammatory response and in severe cases could cause cardiovascular diseases. It is presumed that the intestinal microbiota, and especially its metabolites (LPS and trimethylamine N-oxide (TMAO)), may play an important role in the pathogenesis of arterial hypertension, atherosclerosis, and heart failure. Summary This review focuses on how gut microbiota can change the morphological and functional activity of the cardiovascular system in the course of obesity and in conditions of chronic stress.

scholarly journals Programming of the reproductive axis by hormonal and genetic manipulation in mice

Reproduction ◽  
2018 ◽  
Author(s):  
Susana B Rulli ◽  
María Julia Cambiasso ◽  
Laura D Ratner
Keyword(s):  
Sex Chromosome ◽  
Genetic Manipulation ◽  
Sex Differentiation ◽  
Reproductive Function ◽  
Gonadal Steroids ◽  
Critical Periods ◽  
Female Reproduction ◽  
Control Male ◽  
Male And Female ◽  
The Brain

In mammals, the reproductive function is controlled by the hypothalamic-pituitary-gonadal axis. During development, mechanisms mediated by gonadal steroids exert an imprinting at the hypothalamic-pituitary level, by establishing sexual differences in the circuits that control male and female reproduction. In rodents, the testicular production of androgens increases drastically during the fetal/neonatal stage. This process is essential for the masculinization of the reproductive tract, genitals and brain. The conversion of androgens to estrogens in the brain is crucial for the male sexual differentiation and behavior. Conversely, feminization of the brain occurs in the absence of high levels of gonadal steroids during the perinatal period in females. Potential genetic contribution to the differentiation of brain cells through direct effects of genes located on sex chromosomes is also relevant. In this review, we will focus on the phenotypic alterations that occur on the hypothalamic-pituitary-gonadal axis of transgenic mice with persistently elevated expression of the human chorionic gonadotropin hormone (hCG). Excess of endogenously synthesized gonadal steroids due to a constant hCG stimulation is able to disrupt the developmental programming of the hypothalamic-pituitary axis in both transgenic males and females. Locally produced estrogens by the hypothalamic aromatase might play a key role in the phenotype of these mice. The “four core genotypes” mouse model demonstrated a potential influence of sex chromosome genes in brain masculinization before critical periods of sex differentiation. Thus, hormonal and genetic factors interact to regulate the local production of the neurosteroids necessary for the programming of the male and female reproductive function.

scholarly journals Subfertility in androgen-insensitive female mice is rescued by transgenic FSH

2017 ◽  
Vol 29 (7) ◽  
pp. 1426 ◽  
Author(s):  
K. A. Walters ◽  
M. C. Edwards ◽  
M. Jimenez ◽  
D. J. Handelsman ◽  
C. M. Allan
Keyword(s):  
Androgen Receptor ◽  
Litter Size ◽  
Ovarian Function ◽  
Reproductive Function ◽  
Antral Follicle ◽  
Female Fertility ◽  
Wild Type ◽  
Female Reproduction ◽  
Androgen Insensitivity ◽  
Female Mice

Androgens synergise with FSH in female reproduction but the nature of their interaction in ovarian function and fertility is not clear. In the present study, we investigated this interaction, notably whether higher endogenous FSH can overcome defective androgen actions in androgen receptor (AR)-knockout (ARKO) mice. We generated and investigated the reproductive function of mutant mice exhibiting AR resistance with or without expression of human transgenic FSH (Tg-FSH). On the background of inactivated AR signalling, which alone resulted in irregular oestrous cycles and reduced pups per litter, ovulation rates and antral follicle health, Tg-FSH expression restored follicle health, ovulation rates and litter size to wild-type levels. However, Tg-FSH was only able to partially rectify the abnormal oestrous cycles observed in ARKO females. Hence, elevated endogenous FSH rescued the intraovarian defects, and partially rescued the extraovarian defects due to androgen insensitivity. In addition, the observed increase in litter size in Tg-FSH females was not observed in the presence of AR signalling inactivation. In summary, the findings of the present study reveal that FSH can rescue impaired female fertility and ovarian function due to androgen insensitivity in female ARKO mice by maintaining follicle health and ovulation rates, and thereby optimal female fertility.

scholarly journals Environmental Substances Associated with Alzheimer’s Disease—A Scoping Review

2021 ◽  
Vol 18 (22) ◽  
pp. 11839
Author(s):  
Hanna Maria Elonheimo ◽  
Helle Raun Andersen ◽  
Andromachi Katsonouri ◽  
Hanna Tolonen
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Scoping Review ◽  
Cognitive Abilities ◽  
Human Biomonitoring ◽  
Chemical Exposure ◽  
Priority Substances ◽  
Environmental Chemical ◽  
Other Substances ◽  
Neurological Effects

Alzheimer’s disease (AD) is the most common form of dementia, prevalent in approximately 50–70% of the dementia cases. AD affects memory, and it is a progressive disease interfering with cognitive abilities, behaviour and functioning of the person affected. In 2015, there were 47 million people affected by dementia worldwide, and the figure was estimated to increase to 75 million in 2030 and to 132 million by 2050. In the framework of European Human Biomonitoring Initiative (HBM4EU), 18 substances or substance groups were prioritized for investigation. For each of the priority substances, a scoping document was prepared. Based on these scoping documents and complementary review of the recent literature, a scoping review of HBM4EU-priority substances which might be associated with AD was conducted. A possible association between risk of AD and pesticides was detected. For mercury (Hg), association is possible but inconsistent. Regarding cadmium (Cd) and arsenic (As), the results are inconsistent but inclined towards possible associations between the substances and the risk of disease. The evidence regarding lead (Pb) was weaker than for the other substances; however, possible associations exist. Although there is evidence of adverse neurological effects of environmental substances, more research is needed. Environmental chemical exposure and the related hazards are essential concerns for public health, and they could be preventable.

scholarly journals Reviewing Effective Factors of Alimentary Deficiency in Animals Reproductive Functions

2021 ◽  
Vol 11 (2) ◽  
pp. 157-169
Author(s):  
Pavlo Skliarov ◽  
Serhiy Fedorenko ◽  
Svitlana Naumenko ◽  
Oleksandr Onyshchenko ◽  
Alina Pasternak ◽  
...  
Keyword(s):  
Reproductive Function ◽  
Optimal Level ◽  
The Body ◽  
Reproductive Capacity ◽  
Toxic Substances ◽  
Prevention Measures ◽  
Animal Reproduction ◽  
Number Of Factors ◽  
Wide Range ◽  
Negative Impacts

Animal reproduction is one of the main factors limiting the efficiency of livestock production. Its optimal level is possibly achieved when certain conditions are created for animals. As reproduction is a complex reflex process depending on neuroendocrine regulatory mechanisms, the character and strength of stimuli, which, in turn, is due to a number of factors. Under normal conditions, the body of animals is affected by many different factors, which are appropriately transformed and specified by positive or negative reactions. Inhibitory factors include air pool, saturated with harmful substances and gases, ionizing radiation, poor water quality along with altered redox properties, hypokinesia combined with poor unbalanced feeding, systematic chronic stress, presence of toxic substances in feed, and the deficiency of vitamins and other bioantioxidants in feed or their excessive spending. Of the wide range of genetic and paratypic factors of negative impacts on reproductive capacity, the most common one is alimentary, which causes impaired reproductive function due to deficiencies in the rules, regulations, and feeding regime of animals. In particular, the alimentary can be associated with both general malnutrition (starvation) and overfeeding (obesity). However, the alimentary form of infertility mostly occurs due to low-quality diets when the diet lacks vital components (mainly vitamins, macro-, and micronutrients) or the quantitative ratios of the ingredients are violated. This is possible even if the total nutritional value of the diet meets the established requirements for the physiological needs of the body. Vitamins, micro-, and macronutrients are ecologically deficient factors of disturbance of animal reproductive function, the influence of which is observed on all processes of reproduction, from fertilization to the postpartum period and the preservation of young animals. The pathogenesis of their insufficiency is associated with the violation of steroido-, gameto-, and embryogenesis and the emergence of ante-, intra-, neo- and postnatal pathologies, respectively. Therefore, treatments and prevention measures should be aimed at providing animals with biologically complete balanced feeding and replenishment of the body with vitamins and minerals. However, all these issues remain incompletely studied and need further research.

scholarly journals Linking biomarkersof environmental chemical exposure and endometriosis: integrating the exposome and metabolome in the ENDOXOMICS-b Study

2020 ◽  
Vol 2020 (1) ◽  
Author(s):  
K. Matta ◽  
T. Lefebvre ◽  
Y. Guitton ◽  
P. Marchand ◽  
B. Le Bizec ◽  
...  
Keyword(s):  
Chemical Exposure ◽  
Environmental Chemical

Effects of calcium salts of fatty acids on follicular characteristics and several blood parameters in two fat-tailed sheep breeds

2002 ◽  
Vol 2002 ◽  
pp. 131-131
Author(s):  
M. J. Zamiri ◽  
E. Rowghani ◽  
S. M. Ghoreishi
Keyword(s):  
Fatty Acids ◽  
Plasma Cholesterol ◽  
Post Partum ◽  
Reproductive Function ◽  
Blood Parameters ◽  
Dietary Lipid ◽  
Ovarian Activity ◽  
Corpora Lutea ◽  
Luteal Function ◽  
Sheep Breeds

There is substantial evidence that the increased consumption of fat by dairy cattle can result in an increase in the number ovarian follicles, and the number and size of corpora lutea; it also stimulates post-partum ovarian activity and improve pregnancy rate. Increased dietary lipid also increases plasma cholesterol and progesterone, and the supply of lipoproteins which play significant roles in regulating ovarian steroidogenesis (Willimas, 1996). In contrast to cattle, there are few observations on the effects of dietary lipid on reproductive function in sheep. Intravascular infusion of lipid into ewes stimulated progesterone and prostaglandin synthesis (Burke et al., 1996), and dietary supplementation of calcium soaps of fatty acids enhanced luteal function (Kuran et al., 1999). Calcium soaps of fatty acids have been manufactured in Iran in recent years and sold under the trade name of Megalac. The aim of the present experiment was to study the effects of this protected fat on follicular number and luteal activity in two fat-tailed sheep breeds.

scholarly journals Chlorogenic Acid-Induced Gut Microbiota Improves Metabolic Endotoxemia

2021 ◽  
Vol 12 ◽  
Author(s):  
Xiaolin Ye ◽  
Yang Liu ◽  
Jiajin Hu ◽  
Yanyan Gao ◽  
Yanan Ma ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Chlorogenic Acid ◽  
Fecal Microbiota Transplantation ◽  
Relative Weight ◽  
Intestinal Barrier ◽  
Intestinal Barrier Function ◽  
Oral Glucose ◽  
Therapeutic Effects ◽  
Markers Of Inflammation ◽  
Metabolic Endotoxemia

BackgroundCoffee can regulate glucose homeostasis but the underlying mechanism is unclear. This study investigated the preventive and therapeutic effects of chlorogenic acid (CGA), a polyphenol that is found in coffee, on obesity and obesity-related metabolic endotoxemia.MethodMale 4-week-old C57BL/6 mice were fed either normal chow or a high-fat diet or 20 weeks and half the mice in each group were gavaged with CGA. Oral glucose tolerance tests (OGTTs) and insulin tolerance tests (ITTs) were performed. Markers of inflammation and intestinal barrier function were assayed. The composition of the gut microbiota was analyzed by 16S rRNA high-throughput pyrosequencing. The role of CGA-altered microbiota in metabolic endotoxemia was verified by fecal microbiota transplantation.ResultsCGA protected against HFD-induced weight gain, decreased the relative weight of subcutaneous and visceral adipose, improved intestinal barrier integrity, and prevented glucose metabolic disorders and endotoxemia (P <0.05). CGA significantly changed the composition of the gut microbiota and increased the abundance of short chain fatty acid (SCFA)-producers (e.g., Dubosiella, Romboutsia, Mucispirillum, and Faecalibaculum) and Akkermansia, which can protect the intestinal barrier. In addition, mice with the CGA-altered microbiota had decreased body weight and fat content and inhibited metabolic endotoxemia.ConclusionCGA-induced changes in the gut microbiota played an important role in the inhibition of metabolic endotoxemia in HFD-fed mice.

scholarly journals Fatty acids from diet and microbiota regulate energy metabolism

F1000Research ◽  
2015 ◽  
Vol 4 ◽  
pp. 738 ◽  
Author(s):  
Joe Alcock ◽  
Henry C. Lin
Keyword(s):  
Insulin Resistance ◽  
Metabolic Syndrome ◽  
Fatty Acids ◽  
Gut Microbiota ◽  
Barrier Function ◽  
Unsaturated Fatty Acids ◽  
Intestinal Barrier ◽  
Dietary Fats ◽  
Intestinal Barrier Function ◽  
Metabolic Endotoxemia

A high-fat diet and elevated levels of free fatty acids are known risk factors for metabolic syndrome, insulin resistance, and visceral obesity. Although these disease associations are well established, it is unclear how different dietary fats change the risk of insulin resistance and metabolic syndrome. Here, we review emerging evidence that insulin resistance and fat storage are linked to changes in the gut microbiota. The gut microbiota and intestinal barrier function, in turn, are highly influenced by the composition of fat in the diet. We review findings that certain fats (for example, long-chain saturated fatty acids) are associated with dysbiosis, impairment of intestinal barrier function, and metabolic endotoxemia. In contrast, other fatty acids, including short-chain and certain unsaturated fatty acids, protect against dysbiosis and impairment of barrier function caused by other dietary fats. These fats may promote insulin sensitivity by inhibiting metabolic endotoxemia and dysbiosis-driven inflammation. During dysbiosis, the modulation of metabolism by diet and microbiota may represent an adaptive process that compensates for the increased fuel demands of an activated immune system.

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