scholarly journals De Novo Accumulation of Tetrodotoxin and Its Analogs in Pufferfish and Newt and Dosage-Driven Accumulation of Toxins in Newt: Tissue Distribution and Anatomical Localization

2021 ◽  
Vol 9 (9) ◽  
pp. 1004
Author(s):  
Shigeru Sato ◽  
Rika Kawaura ◽  
Kaito Togashi ◽  
Nanami Mizusawa ◽  
Ko Yasumoto ◽  
...  

The present study was undertaken to determine the amounts of tetrodotoxin (TTX) and its analogs (TTXs) in various tissues of toxin-bearing pufferfish (Canthigaster revulata and Takifugu flavipterus) and newt (Cynops pyrrhogaster) using specific polyclonal antibodies against TTXs, and to compare the obtained results with those mainly determined by high-performance liquid chromatography with fluorescence detection (HPLC-FLD). The anatomical localization of TTXs in these animals was also demonstrated immunohistochemically using the above-mentioned antibody. The ratio of the total amount of TTXs determined by ELISA to that determined by HPLC-FLD changed depending on the tissues examined in pufferfish. Such differences were also observed with the newt in tissue- and individual-dependent manners. Furthermore, TTXs, as well as decarbamoylsaxitoxin (dcSTX), an analog of saxitoxin (STX), were traced for their dynamic changes in tissue distribution, when the newt was fed authentic toxins or toxic animal tissues exogenously, demonstrating that a TTX analog, 5,6,11-trideoxyTTX, and dcSTX were not metabolized into TTX or STX. TTXs-immunoreactive (ir) staining was observed in the pancreas region of the hepatopancreas, the oocytes at the perinucleolus stage, the sac-like tissues just outside the serous membrane of the intestine, and the gland-like structure of the skin, but not in the muscles of pufferfish. TTXs-ir staining was also detected in the mature glands in the dermis of the adult and regenerated tail, but not in the liver, intestine, testis and ovary of the adult newt. TTXs-ir staining was detected in the epithelial cells of the intestine, the ovary, the mucous cells, and the dermis of the TTXs-administered newt. These results suggest that TTXs absorbed from the environment are distributed to various organs or tissues in a species-specific manner, regardless of whether or not these are metabolized in the bodies of toxin-bearing animals.

2018 ◽  
Vol 15 (1) ◽  
pp. 67-73 ◽  
Author(s):  
Guiyun Cao ◽  
Suqiao Han ◽  
Keke Li ◽  
Li Shen ◽  
Xiaohong Wang ◽  
...  

Background: Ferruginol (FRGN) exhibits a broad range of pharmacological properties which make it a promising candidate for chemoprevention. However, little is known about its absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties. Methods: A rapid, sensitive and specific HPLC-DAD method was established to quantify FRGN in the plasma and tissues of Wistar rats. After extraction of FRGN with ethyl acetate (EtOAc), chromatographic separation was performed on a YMC ODS C18 column (250 × 4.6 mm I.D., 5 µm) with a mobile phase consisting of methanol-water (92:8, v/v) at a flow rate of 0.9 mL/min. Detection was conducted with a wavelength of 273 nm at 25 °C. Results: The calibration curves for FRGN were linear in the concentration range of 0.5-20 µg/mL for plasma, 0.5-10 µg/mL for heart, liver, spleen, lung, kidney, stomach, intestine, brain and muscle. After three cycles of freezing and thawing, the concentration variations were within ± 7% of nominal concentrations, indicating no significant substance loss during repeated thawing and freezing. The assay was applied to pharmacokinetic and tissue distribution study in rats. Results suggested that lung, heart, liver, spleen and kidney were the major distribution tissues of FRGN in rats, and FRGN could permeate the blood-brain barrier to distribute in the brain of rats. Conclusion: The information provided by this research is very useful for gaining knowledge of the pharmacokinetic process and tissue distribution of FRGN.


Animals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2226
Author(s):  
Sazia Kunvar ◽  
Sylwia Czarnomska ◽  
Cino Pertoldi ◽  
Małgorzata Tokarska

The European bison is a non-model organism; thus, most of its genetic and genomic analyses have been performed using cattle-specific resources, such as BovineSNP50 BeadChip or Illumina Bovine 800 K HD Bead Chip. The problem with non-specific tools is the potential loss of evolutionary diversified information (ascertainment bias) and species-specific markers. Here, we have used a genotyping-by-sequencing (GBS) approach for genotyping 256 samples from the European bison population in Bialowieza Forest (Poland) and performed an analysis using two integrated pipelines of the STACKS software: one is de novo (without reference genome) and the other is a reference pipeline (with reference genome). Moreover, we used a reference pipeline with two different genomes, i.e., Bos taurus and European bison. Genotyping by sequencing (GBS) is a useful tool for SNP genotyping in non-model organisms due to its cost effectiveness. Our results support GBS with a reference pipeline without PCR duplicates as a powerful approach for studying the population structure and genotyping data of non-model organisms. We found more polymorphic markers in the reference pipeline in comparison to the de novo pipeline. The decreased number of SNPs from the de novo pipeline could be due to the extremely low level of heterozygosity in European bison. It has been confirmed that all the de novo/Bos taurus and Bos taurus reference pipeline obtained SNPs were unique and not included in 800 K BovineHD BeadChip.


Reproduction ◽  
2006 ◽  
Vol 132 (3) ◽  
pp. 455-464 ◽  
Author(s):  
Akiko Hasegawa ◽  
Nozomi Kanazawa ◽  
Hideaki Sawai ◽  
Shinji Komori ◽  
Koji Koyama

The zona pellucida, an extracellular matrix surrounding mammalian oocytes, is composed of three or four glycoproteins. It is well known that the zona pellucida plays several critical roles during fertilization, but there is little knowledge about its formation. The purpose of this study is to examine whether a pig zona pellucida glycoprotein 2 (pZP2) would assemble with mouse zona pellucida. A transgene construct was prepared by placing a minigene encoding pZP2 downstream from the promoter of mouse ZP2. The result showed that the transgenic protein was synthesized in growing oocytes but not incorporated into the zona pellucida. Furthermore, the pZP2 transgene did not rescue the phenotype in ZP2-knockout zona-deficient mice. These results indicate that pZP2 does not participate in mouse zona pellucida formation and the zona pellucida is constituted from its component proteins in a molecular species-specific manner between mice and pigs.


2013 ◽  
Vol 450 (1) ◽  
pp. 159-167 ◽  
Author(s):  
Sweta Maheshwari ◽  
Marina Lavigne ◽  
Alicia Contet ◽  
Blandine Alberge ◽  
Emilie Pihan ◽  
...  

The intra-erythrocytic proliferation of the human malaria parasite Plasmodium falciparum requires massive synthesis of PE (phosphatidylethanolamine) that together with phosphatidylcholine constitute the bulk of the malaria membrane lipids. PE is mainly synthesized de novo by the CDP:ethanolamine-dependent Kennedy pathway. We previously showed that inhibition of PE biosynthesis led to parasite death. In the present study we characterized PfECT [P. falciparum CTP:phosphoethanolamine CT (cytidylyltransferase)], which we identified as the rate-limiting step of the PE metabolic pathway in the parasite. The cellular localization and expression of PfECT along the parasite life cycle were studied using polyclonal antibodies. Biochemical analyses showed that the enzyme activity follows Michaelis–Menten kinetics. PfECT is composed of two CT domains separated by a linker region. Activity assays on recombinant enzymes upon site-directed mutagenesis revealed that the N-terminal CT domain was the only catalytically active domain of PfECT. Concordantly, three-dimensional homology modelling of PfECT showed critical amino acid differences between the substrate-binding sites of the two CT domains. PfECT was predicted to fold as an intramolecular dimer suggesting that the inactive C-terminal domain is important for dimer stabilization. Given the absence of PE synthesis in red blood cells, PfECT represents a potential antimalarial target opening the way for a rational conception of bioactive compounds.


2020 ◽  
Vol 477 (13) ◽  
pp. 2543-2559
Author(s):  
Janka Widzgowski ◽  
Alexander Vogel ◽  
Lena Altrogge ◽  
Julia Pfaff ◽  
Heiko Schoof ◽  
...  

Algae have evolved several mechanisms to adjust to changing environmental conditions. To separate from their surroundings, algal cell membranes form a hydrophobic barrier that is critical for life. Thus, it is important to maintain or adjust the physical and biochemical properties of cell membranes which are exposed to environmental factors. Especially glycerolipids of thylakoid membranes, the site of photosynthesis and photoprotection within chloroplasts, are affected by different light conditions. Since little is known about membrane lipid remodeling upon different light treatments, we examined light induced alterations in the glycerolipid composition of the two Chlorella species, C. vulgaris and C. sorokiniana, which differ strongly in their ability to cope with different light intensities. Lipidomic analysis and isotopic labeling experiments revealed differences in the composition of their galactolipid species, although both species likely utilize galactolipid precursors originated from the endoplasmic reticulum. However, in silico research of de novo sequenced genomes and ortholog mapping of proteins putatively involved in lipid metabolism showed largely conserved lipid biosynthesis pathways suggesting species specific lipid remodeling mechanisms, which possibly have an impact on the response to different light conditions.


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