Showing papers on "Toad published in 2018"
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TL;DR: To fully understand the molecular basis of toad toxins in their use for therapy, a comprehensive understanding of the individual compound contained in toads toxins is necessary; thus, this paper seeks to review the recent studies of some typical compounds frequently identified in toad secretions.
Abstract: Toxins from toads have long been known to contain rich chemicals with great pharmaceutical potential. Recent studies have shown more than 100 such chemical components, including peptides, steroids, indole alkaloids, bufogargarizanines, organic acids, and others, in the parotoid and skins gland secretions from different species of toads. In traditional Chinese medicine (TCM), processed toad toxins have been used for treating various diseases for hundreds of years. Modern studies, including both experimental and clinical trials, have also revealed the molecular mechanisms that support the development of these components into medicines for the treatment of inflammatory diseases and cancers. More recently, there have been studies that demonstrated the therapeutic potential of toxins from other species of toads, such as Australian cane toads. Previous reviews mostly focused on the pharmaceutical effects of the whole extracts from parotoid glands or skins of toads. However, to fully understand the molecular basis of toad toxins in their use for therapy, a comprehensive understanding of the individual compound contained in toad toxins is necessary; thus, this paper seeks to review the recent studies of some typical compounds frequently identified in toad secretions.
50 citations
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TL;DR: The results provide the guides for the use of toad poison-peptides in therapeutics and new drug development and conclude that the poison is a potent agent capable of slaying a predator.
Abstract: Anuran toxins released from the skin glands are involved in defence against predators and microorganisms. Secretion from parotoid macroglands of bufonid toads is a rich source of bioactive compounds with the cytotoxic, cardiotoxic and hemolytic activity. Bufadienolides are considered the most toxic components of the toad poison, whereas the protein properties are largely unknown. In the present work, we analysed the cardio-, myo-, and neurotropic activity of extract and the selected proteins from Bufo bufo parotoids in in vitro physiological bioassays carried out on two standard model organisms: beetles and frogs. Our results demonstrate a strong cardioactivity of B. bufo gland extract. The toad poison stimulates (by 16%) the contractility of the insect heart and displays the cardioinhibitory effect on the frog heartbeat frequency (a 27% decrease), coupled with an irreversible cardiac arrest. The gland extract also exhibits significant myotropic properties (a 10% decrease in the muscle contraction force), whereas its neuroactivity remains low (a 4% decrease in the nerve conduction velocity). Among identified peptides present in the B. bufo parotoid extract are serine proteases, muscle creatine kinase, phospholipid hydroperoxide glutathione peroxidase, cytotoxic T-lymphocyte protein, etc. Some proteins contribute to the cardioinhibitory effect. Certain compounds display the paralytic (myo- and neurotropic) properties. As the toad gland extract exhibits a strong cardiotoxic activity, we conclude that the poison is a potent agent capable of slaying a predator. Our results also provide the guides for the use of toad poison-peptides in therapeutics and new drug development.
27 citations
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TL;DR: The results suggest that LPS delays the release of spermatozoa, possibly due to alterations in serum levels of testosterone and (or) gonadotropins, which may also explain fewer degrading cells in Bidder’s organ.
Abstract: Anurans can be naturally infected by the bacterium Escherichia coli (Migula, 1895) Castellani and Chalmers, 1919, which contain lipopolysaccharides (LPS) in their external membrane. LPS affects rep...
6 citations
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TL;DR: Evidence of sex differences in exploratory behaviour of amphibians obtained under controlled laboratory conditions is obtained, with males demonstrating more intensive and more goal-oriented exploratories behaviour than females.
3 citations
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TL;DR: Toad brain AChE was less sensitive to in vitro inhibition by CPO, and studies of inhibitor kinetics indicated substantially lower anticholinesterase potency of CPO against the toad brain enzyme, suggesting the relatively low sensitivity of toads to cholinergic toxicity may be attributable to more effective target‐site detoxification.
Abstract: We compared biochemical, functional, and behavioral responses to the organophosphorus anticholinesterase chlorpyrifos oxon (CPO) in mice (Mus musculus, CD-1) and toads (Anaxyrus cognatus, Great Plains toad). Toads were substantially less sensitive to acute lethality of CPO based on the maximum tolerated (nonlethal) dose (toads, 77 mg/kg; mice, 5.9 mg/kg). Sublethal exposures led to classical signs of toxicity (increased involuntary movements, autonomic secretions) in mice but hypoactivity in toads. Motor performance in an inclined plane test was not affected by CPO in mice but was altered at the highest dosage in toads. Acetylcholinesterase (AChE), butyrylcholinesterase, monoacylglycerol lipase, and fatty acid amide hydrolase activities in brain were inhibited in mice but not in toads, and fatty acid amide hydrolase activity in the liver was inhibited in both species. Toad brain AChE was less sensitive to in vitro inhibition by CPO (50% inhibitory concentration [IC50; 20 min, 37 °C], 101 vs 7.8 nM; IC50 [20 min, 26 °C], 149 vs 6.2 nM), and studies of inhibitor kinetics indicated substantially lower anticholinesterase potency of CPO against the toad brain enzyme. Using an in vitro indirect inhibition assay, preincubation of CPO with toad brain homogenate was more effective than an equivalent mouse brain homogenate at reducing CPO potency. These data suggest that the relatively low sensitivity of toads to cholinergic toxicity is based on the low sensitivity of brain AChE, which in turn may be attributable to more effective target-site detoxification. Environ Toxicol Chem 2018;37:1898-1906. © 2018 SETAC.
2 citations
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TL;DR: The structure of the dorsal lingual surface tongue of the toad, Bufo bufo habitat in the west of Iran is investigated, showing that a non-keratinised pseudo stratified columnar epithelium with ciliated cells lined the lingual papillae.
Abstract: The present study investigated the structure of the dorsal lingual surface tongue of the toad, Bufo bufo habitat in the west of Iran. The tongue of the toad contains two types of lingual papillae; fungiform papillae and filiform papillae. The fungiform papillae are usually scattered among the filiform papillae and are believed to function in gustation and in the secretion of salivary fluid. Light microscopic observations showed that a non-keratinised pseudo stratified columnar epithelium with ciliated cells lined the lingual papillae. Scanning electron microscopic examinations revealed that a taste disc (honeycomb) was located at the apical surface of each fungiform papillae. The surface of the disc had a latticework pattern. However, no ciliated cells were observed in the surrounding area of the sensory disc. As a result, the morphology of the lingual epithelium of the Bufo Bufo is species-specific. However, it is somewhat similar to that of Bufo japonicus and distinctly different from that of Bufo regularis.
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04 May 2018
TL;DR: Wang et al. as discussed by the authors proposed a toad shed skin six-step collection method, which comprises the six steps of selecting toads, hungering the toads in a dry environment, cleaning the loads, shedding skin of the loads and collecting the toad sloughs and can address the problems that in traditional toad feeding, it is difficult to shed and collect the skin.
Abstract: The invention discloses a toad shed skin six-step collection method. The method comprises the six steps of selecting toads, hungering the toads in a dry environment, cleaning the loads, shedding skinof the loads, preparing toad sloughs and collecting the toad sloughs and can address the problems that in traditional toad feeding, it is difficult to shed and collect the skin, and therefore toad farmers can easily complete toad skin shedding and collecting in the toad feeding process, so that the toad feeding scale can be drastically increased, and the feeding benefits of the toad farmers are ensured. At the same time, the overall quality of the toad sloughs can be guaranteed and the overall medicinal property of the toad sloughs can be dramatically improved. According to the toad shed skinsix-step collection method, the six steps are closely linked with one another. The toad shed skin six-step collection method is ingenious in design, simple, easy to operate and quite suitable for large-area use and popularization.