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Frontiers in Biology

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, Volume 13 Issue 5 Previous Issue   
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Androgen and estrogen receptors in placental physiology and dysfunction
Erin S McWhorter, Jennifer E Russ, Quinton A Winger, Gerrit J Bouma
Front. Biol.. 2018, 13 (5): 315-326.
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BACKGROUND: The placenta is recognized as an endocrine organ, largely due to its secretions of steroid hormones, including progesterone, androgens, and estrogens. Steroid hormones play an essential role in the progression of pregnancy, fetal development, and growth. Furthermore, steroids are necessary for establishment and maintenance of a normal pregnancy, preparing the endometrium for implantation, stimulating endometrial secretions, and regulating uterine blood flow, however the exact mechanism of sex steroid signaling through their receptors in placental function is unknown.

OBJECTIVE: In this review, we will provide an overview of the current knowledge on sex steroid receptors in normal placental development, as well as evidence of abnormal signaling associated with placental dysfunction.

METHODS: A systematic literature search was performed using the NCBI PubMed search engine, including the following key works: estrogen receptor, androgen receptor, placenta, placental development, cytotrophoblast, and differentiation.

RESULTS: Of the over 700 articles that were returned, 125 studies focused on estrogen and androgen receptors in human placenta development and function during normal and abnormal pregnancy, as well as in rodents and ruminants placentae.

CONCLUSION: Receptors for both estrogens and androgens have been localized within the mammalian placenta, but surprisingly little is known about their signaling in trophoblast cell differentiation and function. An emerging picture is developing in which estrogen receptors possibly play role in cytotrophoblast proliferation and extravillous trophoblast invasion, whereas androgen receptors are involved in syncytiotrophoblast differentiation and function.

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The journey of gut microbiome – An introduction and its influence on metabolic disorders
Ankita Chattopadhyay, Mythili S.
Front. Biol.. 2018, 13 (5): 327-341.
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BACKGROUND: Metabolic disorders such as Obesity, Diabetes Type 2 (T2DM) and Inflammatory Bowel Diseases (IBD) are the most prevalent globally. Recently, there has been a surge in the evidence indicating the correlation between the intestinal microbiota and development of these metabolic conditions apart from predisposing genetic and epigenetic factors. Gut microbiome is pivotal in controlling the host metabolism and physiology. But imbalances in the microbiota patterns lead to these disorders via several pathways. Animal and human studies so far have concentrated mostly on metagenomics for the whole microbiome characterization to understand how microbiome supports health in general. However, the accurate mechanisms connecting the metabolic disorders and alterations in gut microbial composition in host and the metabolites employed by the microorganisms in regulating the metabolic disorders is still vague.

OBJECTIVE: The review delineates the latest findings about the role of gut microbiome to the pathophysiology of Obesity, IBD and Diabetes Mellitus. Here, we provide a brief introduction to the gut microbiome followed by the current therapeutic interventions in restoration of the disrupted intestinal microbiota.

METHODS: A methodical PubMed search was performed using keywords like “gut microbiome,” “obesity,” “diabetes,” “IBD,” and “metabolic syndromes.” All significant and latest publications up to January 2018 were accounted for the review.

RESULTS: Out of the 93 articles cited, 63 articles focused on the gut microbiota association to these disorders. The rest 18 literature outlines the therapeutic approaches in maintaining the gut homeostasis using probiotics, prebiotics and faecal microbial transplant (FMT).

CONCLUSION: Metabolic disorders have intricate etiology and thus a lucid understanding of the complex host-microbiome inter-relationships will open avenues to novel therapeutics for the diagnosis, prevention and treatment of the metabolic diseases.

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Phototropism in land plants: Molecules and mechanism from light perception to response
Johanna Morrow, Kyle T. Willenburg, Emmanuel Liscum
Front. Biol.. 2018, 13 (5): 342-357.
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BACKGROUND: Phototropism is the response a plant exhibits when it is faced with a directional blue light stimulus. Though a seemingly simple differential cell elongation response within a responding tissue that results in organ curvature, phototropism is regulated through a complex set of signal perception and transduction events that move from the plasma membrane to the nucleus. In nature phototropism is one of several plant responses that have evolved to optimize photosynthesis and growth.

OBJECTIVE: In the present work we will review the state of the field with respect to the molecules and mechanisms associated with phototropism in land plants.

METHODS: A systematic literature search was done to identify relevant advances in the field. Though we tried to focus on literature within the past decade (1998-present), we have discussed and cited older literature where appropriate because of context or its significant impact to the present field. Several previous review articles are also cited where appropriate and readers should seek those out.

RESULTS: A total of 199 articles are cited that fulfill the criteria listed above.

CONCLUSIONS: Though important numerous and significant advances have been made in our understanding of the molecular, biochemical, cell biological and physiologic mechanisms underlying phototropism in land plants over the past decade, there are many remaining unanswered questions. The future is indeed bright for researchers in the field and we look forward to the next decade worth of discoveries.

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Investigation of the relationship between cell surface hydrophobicity and demulsifying capability of biodemulsifier-producing bacteria
Hoda Sabati, Hossein Motamedi
Front. Biol.. 2018, 13 (5): 358-365.
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BACKGROUND: Cell surface hydrophobicity (CSH) is one of the key physicochemical features of biodemulsifier-producing bacteria that influence their demulsification capability maintenance in petroleum contaminated environments.

METHODS: In present study, biodemulsifier-producing bacteria were isolated from petroleum contaminated environments using different isolation media and the correlation between their CSH and demulsifying ability was investigated. The demulsifying ability of isolates was measured through demulsification tests on water in kerosene emulsions. The microbial adhesion to the hydrocarbon (MATH) assay was used to denote their CSH.

RESULTS: The evaluation of CSH showed that majority of biodemulsifier producing bacteria have high CSH which indicating a positive correlation between CSH and demulsifying capability.

CONCLUSIONS: According to these results it can be concluded that CSH can be used as an indicator for assessment of biodemulsifier-producing bacteria and screening of new isolates for their biodemulsifier production.

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Effect of a normal protein diet on oxidative stress and organ damage in malnourished rats
Hanane Gourine, Hadria Grar, Wafaa Dib, Nabila Mehedi, Ahmed Boualga, Djamel Saidi, Omar Kheroua
Front. Biol.. 2018, 13 (5): 366-375.
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BACKGROUND: We investigated the effects of three weeks of renutrition with a normal protein diet on oxidant/antioxidant status in malnourished rats using biochemistry and histology.

METHODS: Eighteen young Wistar rats were divided into three groups: control group was fed on a normal protein diet; malnourished group was fed on low protein diet and renourished group was fed on low protein diet followed by a normal protein diet. Serum albumin was evaluated. Malondialdehyde, protein carbonyl, superoxide dismutase and catalase levels were determined in the intestine, muscle and liver. Intestinal and hepatic damage were assessed by histological examination.

RESULTS: Protein malnutrition resulted in a significant decrease of body weight, albumin level, villus length, intraepithelial lymphocytes counts (IELC) and superoxide dismutase level (liver and muscle). However, catalase activity increased significantly in muscle and gut but there was no difference in liver. In all organs, malondialdehyde and protein carbonyl content of malnourished group showed a significant increase. Interestingly, a normal protein diet for three weeks resulted in a return to normal levels of superoxide dismutase, albumin, malondialdehyde and protein carbonyl in all organs. Catalase activity decreased in the muscle and gut and exhibited no significant difference in the liver. The renutrition diet enhanced also the recovery of intestinal epithelium by increasing villus length. Hepatic damage of rats fed normal protein diet was markedly reduced (macrovesicular steatosis decreased by 45%).

CONCLUSION: The normal protein diet could improve the oxidant/antioxidant imbalance and organ damage induced by protein malnutrition.

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Multifaceted roles of ASB proteins and its pathological significance
Vivek Vishnu Anasa, Palaniyandi Ravanan, Priti Talwar
Front. Biol.. 2018, 13 (5): 376-388.
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BACKGROUND: Post-translational (PT) modification in cells regulates many intracellular events like signal transduction, transcription, cell cycle, protein quality control, apoptosis and cellular development. Ubiquitination is one of the PT modifications which functions as a marker for degradation of target proteins by the proteasome and as a regulatory mechanism for several signalling pathways. The ubiquitination mechanism requires multiple enzymes, including E1, E2, and E3 ligases. Among them, E3 ligases play a major role in recognizing target proteins and an essential feature of protein homeostatic mechanisms within the cell. Most of the ASB (ankyrin repeat SOCS box) proteins function as RING family of E3 ubiquitin ligases characterized by the presence of two conserved domains N-terminal ankyrin repeat and C-terminal SOCS box domain

METHODS and RESULTS: Current studies have shown that some ASBs function as important regulators of several signalling pathways. This review gives an overview of ASB proteins on numerous cellular processes such as insulin signalling, spermatogenesis, myogenesis and in cellular development. Including various pathological situations, such as cancer, primary open-angle glaucoma, and inflammation, indicating that ASBs has important functions in both normal and pathological development

CONCLUSIONS: This article provides a precise comprehensive focus on ASBs protein structure, its biological functions, and their pathological significance.

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Peak systolic velocity Doppler of middle cerebral artery in small for gestational age (SGA) fetus
Kobra Shojaei, Hora Motamed, Mojgan Barati
Front. Biol.. 2018, 13 (5): 389-393.
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BACKGROUND: Small for gestational age (SGA) has high frequency which increases the risk of long-term adverse outcomes. Thus the aim of this study was to evaluate peak systolic velocity Doppler of middle cerebral artery (MCA) in SGA fetus in order to find appropriate method to diagnosis SGA sooner.

MATERIALS and METHODS: This prospective longitudinal study was conducted on 90 pregnant women with a diagnosis of SGA fetus and 90 pregnant women with normal fetus. Then MCA and umbilical artery assessment were performed for all subjects and compared between two groups.

RESULTS: Doppler assessment showed that umbilical artery PI was significantly higher in SGA group as compared to normal group (1.11±0.37 vs 0.98±0.18, P = 0.003), while MCA PI was significantly lower in SGA group (1.77±0.44 vs 1.92±0.47, P = 0.028). On the other hand, PSV did not differ between the groups (P = 0.592). Moreover, we found that PSV was more in SGA group by grouping maternal age (<27 years) (P = 0.006), and gestational age (>34 weeks) (P<0.001).

CONCLUSION: The results of this study suggest that MCA PI decreased significantly in SGA fetuses, while UA PI increased in this group. Moreover, PSV increased in this group when evaluated in different subgroups (based on maternal age and gestational age).

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