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Biochemical Markers in Ophthalmology
Published in Ching-Yu Cheng, Tien Yin Wong, Ophthalmic Epidemiology, 2022
Abdus Samad Ansari, Pirro G. Hysi
Metabolomics have also been used to evaluate several retinal diseases, including AMD [130], diabetic retinopathy (DR) [131], rhegmatogenous retinal detachment [132], and proliferative vitreoretinopathy (PVR) [133]. Significant differences in plasma metabolites have been seen in patients with AMD compared to controls, varying with severity of disease. This most noticeable include variability in certain amino acids, lipid, and nucleotide profiles, with pathway analysis identifying clear changes in glycerophospholipid, purine, taurine and hypotaurine, and nitrogen metabolism [134]. Other metabolites associated with disease include N-acetyl-l-alanine, l-tyrosine, l-phenylalanine, l-methionine, and l-arginine. It is believed that many of these variances are linked to oxidative stress and amino acid metabolism. Other differences identified include that of glutamate and glutamine which are associated with neurotransmitter supply within the retina. One study comparing urinary metabolomic signatures in patients with different stages of AMD to those of controls found depletion of certain amino acids and citrate was associated with disease [135].
Chemoreception in Aquatic Invertebrates
Published in Robert H. Cagan, Neural Mechanisms in Taste, 2020
Barry W. Ache, William E. S. Carr
The defined specificity of the taurine-sensitive chemosensory cells of the spiny lobster exhibits similarities to taurine recognition systems in internal tissues of mammals. Hence, hypotaurine and β-alanine, the two most potent taurine analogs in the lobster, are both potent competitors for taurine binding sites in rat brain synaptosomes101 and taurine uptake sites in the heart.102 The apparent suppressive interaction of taurine and glycine described in Section III.C and Figure 5 is particularly interesting because of the finding that, in certain excitable tissues of mammals, taurine is thought to interact with glycine receptors.103
Radioactive Se And Te Labeled Imaging Agents
Published in Garimella V. S. Rayudu, Lelio G. Colombetti, Radiotracers for Medical Applications, 2019
Selenium-75 labeled β-aminoethyl selenosulfate (H2NCH2CH2SeO3H), a taurine (H2NCH2CH2SO3H) analog, has been prepared and the pancreas uptake in rats was comparable to that of Se-75 selenomethionine (3.44 and 5.34 %dose/g, respectively).27 The liver uptake for Se-75 aminoethyl selenosulfate was lower and therefore the pan-creas:liver ratio did not differ significantly for these two compounds. A similar type of analog, selenohypotaurine (H2NCH2CH2SeO2H), also showed similar pancreas uptake.28 These two studies suggested that Se-75 labeled taurine or hypotaurine analogs may be useful for pancreas imaging, provided that the biological half-lifes for these agents are shorter (lower radiation dose).
Modified Taohong Siwu decoction improves cardiac function after myocardial ischaemia and reperfusion in rats by promoting endogenous stem cell mobilization and regulating metabolites
Published in Pharmaceutical Biology, 2022
Wan-ting Meng, Zhong-Xin Xiao, Han Li, Ya-chao Wang, Yue Zhao, Yan Zhu, Hai-dong Guo
Furthermore, to investigate the long-term therapeutic effects of high-dose modified THSWD on I/R rats, we collected the serum of rats after 4 weeks of high-dose modified THSWD treatment. We performed metabolomic analyses using UPLC-MS. We found significant differences in the metabolite profiles between the two groups. The top 25 metabolites are displayed on a heatmap (Figure 8). We chose different metabolites between the high-dose modified THSWD and I/R groups based on the screening criteria [FC ≥1.5 (≤0.67) and p ≤ 0.05] (Table 1). High-dose modified THSWD increased the levels of glycine trimethyl internal salts and anthocyanins, which could reduce the risk of MI. Through the MetPA database analysis, we evaluated the related metabolic pathways. The results suggested that high-dose modified THSWD mainly affected the metabolism of phosphonate and phosphonate, as well as the metabolism of taurine and hypotaurine (Table 2).
Modulating the lipid profile of blastocyst cell membrane with DPPC multilamellar vesicles
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2022
Hugo De Rossi, Camila Bortoliero Costa, Luana Teixeira Rodrigues-Rossi, Giovana Barros Nunes, Dóris Spinosa Chéles, Isabella Maran Pereira, Daniele F. O. Rocha, Eloi Feitosa, Ana Valéria Colnaghi Simionato, Gisele Zoccal Mingoti, Pedro Henrique Benites Aoki, Marcelo Fábio Gouveia Nogueira
Matured COCs were removed from the IVM medium, transferred to 90 µL of IVF medium composed of Tyrode’s albumin lactate pyruvate (TALP) containing 0.2 mmol/L pyruvate, 25 mmol/L sodium bicarbonate, 13 mmol/L of sodium lactate, 50 μg/mL amikacin, 6 mg/mL fatty acid-free BSA, 10 μg/mL heparin, 20 μmol/L penicillamine, 10 μmol/L hypotaurine, and 2 μmol/L epinephrine (TALP-IVF medium), and covered with silicone oil. For insemination, straws of cryopreserved semen from Nellore bulls (previously tested) were used. The straws were thawed at 37 °C for 30 s, and the contents were subjected to centrifugation using a Percoll discontinuous density gradient (45% and 90%; GE Healthcare, Uppsala, Sweden) at 2500 × g for 7 min at room temperature. The supernatant was discarded, and the pellet was resuspended in 500 μL of TALP medium and centrifuged again at 5000 × g for 5 min. Sperm cells (2 × 106 cells/mL) were added to a drop of the TALP-IVF medium. COCs and sperm cells were co-incubated for 18 h under the same conditions as in the maturation stage. The start of IVF was defined as day 0 (D0).
Time to re-evaluate ART protocols in the light of advances in knowledge about methylation and epigenetics: an opinion paper
Published in Human Fertility, 2018
Yves Menezo, Brian Dale, Kay Elder
Tunc and Tremellen (2009) were the first to demonstrate this correlation in male gametes. In vivo, the early embryo is protected from oxidative stress (OS) by numerous redundant metabolic systems that include Vitamin C, hypotaurine and glutathione associated with various superoxide dismutases (Guérin, El Mouatassim, & Ménézo, 2001; Menezo, Silvestris, Dale, & Elder, 2016). The fact that methylation occurs on CpG islands is an important feature to bear in mind, since guanine is the nucleotide base that is most sensitive to oxidation, leading to 8-oxo deoxyguanosine formation. Methylation on CpG islands and CG sequences cannot be accomplished correctly if guanine is oxidized. 5HmC is the oxidation product of MethylCytosine, and abnormal uncorrected levels can induce active aberrant DNA demethylation. Oxidative damage to DNA may therefore result in heritable epigenetic changes via modifications of chromatin organization (Donkena, Young, & Tindall, 2010; Maltseva, Baykov, Jeltsch, & Gromova, 2009), aberrant hypermethylation of some gene promoter regions and global hypo-methylation. The high levels of Hcy generated by controlled ovarian stimulation must be recycled to potentially generate Glutathione (GSH): the preimplantation embryo cannot use the CBS pathway, which is absent, in oocytes. Hcy is a cause and a consequence of OS (Hoffman, 2011), and systems for its recycling in the oocyte and embryo are unstable/‘fragile’.