Effects of daily exposure to saccharin sodium and rebaudioside A on the ovarian cycle and steroidogenesis in rats

Wang

2019

Front. Cell Dev. Biol.

Follicular development and following ovulation induced by luteinizing hormone (LH) surge are critical for ovarian functions, but the molecular mechanism regulating ovarian ovulation attracts more attention and remains mainly unknown. Recent researches on the nucleotide leukin rich polypeptide 3 (NLRP3) inflammasome shred light on it. Given pregnant mare serum gonadotropin (PMSG) can not only trigger the follicular development, but also induce the following ovulation, the present study therefore examined that expression and localization of NLRP3 inflammasome through immunohistochemistry and Western blotting during the follicular development induced by PMSG. The results showed expressions of NLRP3 and the adaptor protein apoptosis-associated speck-like protein (ASC) significantly increased in the outside of intrafollicular fluid, further analysis found that caspase-1 was activated and IL-1β production was also upregulated after 52 h-treatment of PMSG. Furthermore, a significant increase of ovulation-related genes, hypoxia inducible factor (HIF)-1α and endothelin (ET)-1, was found after 52 h-treatment of PMSG. To our knowledge, it is the first time to clearly indicated the activation of NLRP3 inflammasome may contribute to the ovulation of PMSG-treated ovaries, which will help to further clarify the ovulatory mechanism in mammals.

Section: Introductionmentioning

confidence: 99%

Expression and Contribution of NLRP3 Inflammasome During the Follicular Development Induced by PMSG

Wang

2019

Front. Cell Dev. Biol.

“…The sections were stained with H&E, and histopathological changes were then viewed under a YS100 microscope (Nikon, Tokyo, Japan). Four (4) sections from each stage were observed for determination of apoptotic and autophagic cells in the tissues as reported previously [39].…”

Section: Methodsmentioning

confidence: 99%

Denatonium Benzoate-Induces Oxidative Stress in the Heart and Kidney of Chinese Fast Yellow Chickens by Regulating Apoptosis, Autophagy, Antioxidative Activities and Bitter Taste Receptor Gene Expressions

Hamdard

Shi

et al. 2019

Animals

Self Cite

Simple SummaryDenatonium benzoate is a strong bitter taste receptor agonist, extensively used for its activation of different cell pathways. Taste signals have been associated to food recognition and avoidance, and bitter taste provokes an aversive reaction and is assumed to protect chickens from consuming poisons and harmful toxic substances. The results of the study revealed that dietary supplementation with medium and high doses of denatonium benzoate damaged the epithelial cells of the heart and kidneys by inducing apoptosis and autophagy and reduced the growth of chickens, respectively. However, mRNA expressions of bitter taste receptors, downstream signaling effector genes, apoptosis-, autophagy- and antioxidant-related genes were higher on day 7, while these expressions were subsequently decreased on day-28 in the heart and kidney of Chinese Fast Yellow chickens in a dose-response manner.AbstractThe sense of taste which tells us which prospective foods are nutritious, poisonous and harmful is essential for the life of the organisms. Denatonium benzoate (DB) is a bitter taste agonist known for its activation of bitter taste receptors in different cells. The aim of the current study was to investigate the mRNA expressions of bitter taste, downstream signaling effectors, apoptosis-, autophagy- and antioxidant-related genes and effector signaling pathways in the heart/kidney of chickens after DB dietary exposure. We randomly assigned 240, 1-day-old Chinese Fast Yellow chicks into four groups with five replicates of 12 chicks and studied them for 28 consecutive days. The dietary treatments consisted of basal diet and feed containing DB (5, 20 and 100 mg/kg). The results revealed that dietary DB impaired (p < 0.05) the growth performance of the chickens. Haemotoxylin and eosin staining and TUNEL assays confirmed that medium and high doses of DB damaged the epithelial cells of heart/kidney and induced apoptosis and autophagy. Remarkably, the results of RT-PCR and qRT-PCR indicated that different doses of DB gradually increased (p < 0.05) mRNA expressions of bitter taste, signaling effectors, apoptosis-, autophagy- and antioxidant- related genes on day 7 in a dose-response manner, while, these expressions were decreased (p < 0.05) subsequently by day-28 but exceptional higher (P < 0.05) expressions were observed in the high-dose DB groups of chickens. In conclusion, DB exerts adverse effects on the heart/kidney of chickens in a dose-response manner via damaging the epithelium of the heart/kidney by inducing apoptosis, autophagy associated with bitter taste and effector gene expressions. Correlation analyses for apoptosis/autophagy showed agonistic relationships. Our data provide a novel perspective for understanding the interaction of bitter taste, apoptosis, autophagy and antioxidative genes with bitter taste strong activators in the heart/kidney of chicken. These insights might help the feed industries and pave the way toward innovative directions in chicken husbandry.

“…Guinea pigs were randomly divided into five groups consisting of six animals per group, and received normal water (Control), 1.5 mM (low dose, L-SS) or 7.5 mM (high dose, H-SS) sodium saccharin solution, or 0.5 mM (low dose, L-RA) or 2.5 mM (high dose, H-RA) rebaudioside A solution available ad libitum for 28 consecutive days, respectively. The sweetness of the low-dose or high-dose sodium saccharin and rebaudioside A was designed to be equivalent to a previously published method (Jiang et al, 2018). Food intake and water consumption were determined every day in the morning, body weight was determined at days 1, 7, 14, 21 and 28, the weight of the right ovary in animals was determined per group after sample collection.…”

Section: Animals and Experimental Designmentioning

confidence: 99%

“…The sections in the negative control (NC) group were incubated with normal rabbit serum, instead of primary antibody. All sections were viewed under a light microscope Nikon Eclipse 80i (Nikon), and the staining intensities of the sweet taste receptors in the ovaries and uteri were determined based on the method established in a previous study (Jiang et al, 2018), and were evaluated by three independent observers and repeated three times per sample.…”

Section: Immunohistochemistrymentioning

confidence: 99%

Influences of non‐nutritive sweeteners on ovarian and uterine expression of T1R2 and T1R3 in peripubertal female guinea pigs

Shen

Shi

et al. 2020

Animal Science Journal

Self Cite

The qualities of the five basic tastes, namely, sweet, bitter, sour, salty, and umami, can be detected and discriminated by specific subsets of taste receptor cells in mammals (Lindemann, 2001). Taste sensations are initiated in these taste receptor cells by the interaction of sapid molecules with G protein-coupled receptors (GPCRs) (Sugita, Yamamoto, Hirono, & Shiba, 2013). As a family of GPCRs, the taste receptor type 1 subunit 2 (T1R2) and taste receptor type 1 subunit 3 (T1R3) have been shown to be the principal sweet receptors (Chandrashekar, Hoon, Ryba, & Zuker, 2006; Zhao et al., 2003). T1R3 combines with T1R2 to form a heteromeric receptor having three different agonist binding sites, including a Venus flytrap domain (VFD), a cysteine-rich domain (CRD), and a 7-transmembrane domain (TMD) (Dubois, 2016), to respond to different sweet tastants, such as carbohydrate sugar, artificial sweetener, sweet protein, and amino acid (Nelson et al., 2001). In a previous study, T1R2 VFD loci were identified for sucrose, fructose, saccharin, aspartame, and D-tryptophan amino acid (