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Inhalation Toxicity of Metal Particles and Vapors
Published in Jacob Loke, Pathophysiology and Treatment of Inhalation Injuries, 2020
Arsenic has been used therapeutically for more than 2000 years (Frost, 1967). Medicinal uses of arsenic have ranged from treatment of syphilis to use as a tonic. Arsenicals act locally and are slow corrosives; they have been used in the treatment of skin cancer. In the United States there has been a decline in the use of arsenicals in human medicine but the decrease has not been as great in veterinarian or agricultural use (e.g., sodium arsenite as a weed killer).
Stress Proteins in Renal Ischemia
Published in John J. Lemasters, Constance Oliver, Cell Biology of Trauma, 2020
ATP and glutathione concentrations decrease dramatically in ARF. Helenius and colleagues suggest that these decreases would cause dramatic changes in protein folding and aggregation. They found that correct folding of hemagglutinin requires ATP. In cells depleted of ATP, large covalent aggregates of hemagglutinin formed in association with BiP, a chaperone. Addition of DTT reduced the aggregate. Correct folding required appropriate disulfide bonds that formed in the presence of glutathione.49,50 Without ATP and glutathione, inappropriate -SH bonds formed and aggregation resulted. Therefore, in vitro Helenius and colleagues observe that proper protein folding after synthesis requires ATP and glutathione. HSP 72/73 showed similar behavior in HeLa cells when Beckmann et al. studied metabolic stress.47 In normal, unstressed cells, cytosolic HSP 70 associated transiently with polypeptides as they were synthesized. In cells exposed to stress (sodium arsenite), this association became long lasting. In cells depleted of ATP, HSP 70 also became bound to insoluble aggregates of nascent polypeptides. If the magnitude or duration of stress increased, mature proteins (as well as newly synthesized proteins) became stably bound to HSP 72/73. Beckmann et al. suggest that the decrease in soluble HSP 70 is a signal for activation of the heat shock response.47
Methods of Protein Iodination
Published in Erwin Regoeczi, Iodine-Labeled Plasma Proteins, 2019
Randerath provides an excellent protocol of how to make the reagent. Iodination of the ester is accomplished by using chloramine-T, but sodium arsenite (NaAsO2) is used for reduction (instead of metabisulfite) because, according to the author, this results in a greater purity of the final reagent. The N-hydroxysuccinimide-carbohydrazide exchange is effected immediately after the iodination by the addition of an excess of carbohydrazide, followed by extraction in benzene, as already familiar from the Bolton-Hunter procedure.
Cell cycle dysregulation on prenatal and postnatal arsenic exposure in skin of Wistar rat neonates
Published in Xenobiotica, 2023
Navneet Kumar, Astha Mathur, Suresh Kumar Bunker, Placheril J. John
The most significant indicators of apoptosis are caspases and Bcl-2 family members, which include the pro- and anti-apoptotic proteins Bax and Bcl-2 (Arshad et al. 2015; Zeng et al. 2019). Additionally, the enhanced apoptosis may be related to the disparity in Bax and Bcl-2 expression (Yun et al. 2011). We observed a dose dependent upregulation in the transcript level expressions of caspase 3, caspase 7 and caspase 9 in LDG, MDG and HDG in comparison to control groups with comparatively higher upregulation observed in caspase 7. In a study, rats administered 10 mg/kg sodium arsenite for 2 days showed similar results (Das et al. 2009). Our findings also indicated that treatment with arsenite increased the transcript expression levels of Bax, while decreased the levels of Bcl-2 transcript expression, suggesting that epidermal cells of neonates accept the signal to induce apoptosis.
Betaine attenuates sodium arsenite-induced renal dysfunction in rats
Published in Drug and Chemical Toxicology, 2022
Sumedha Sharma, Tajpreet Kaur, Ashwani Kumar Sharma, Balbir Singh, Devendra Pathak, Harlokesh Narayan Yadav, Amrit Pal Singh
Thirty rats were randomly divided into four groups. Sodium arsenite (CAS No. 7784–46-5, ≥98.5% pure, S.D. Fine Chemicals Ltd., India) and betaine (CAS No. 107–43-7, ≥98% pure, Sigma Aldrich, India) were dissolved in distilled water. Group 1 served as control (n = 6) and received distilled water (5 mL/kg, oral) once daily for 28 days. In group 2, sodium arsenite (5 mg/kg, oral, n = 8) was given to rats for 4 weeks to induce nephrotoxicity. In groups 3 and 4, betaine (125 and 250 mg/kg, oral, n = 8) was administrated 1-h after arsenic administration in rats for 4 weeks. Based on the literature search, the two levels of betaine were selected for the present study (Ganesan et al. 2011; Hagar and Al Malki 2014; Hagar et al., 2015; Khodayar et al. 2018). Administration of betaine (250 mg/kg) upto 6 weeks has been reported to produce no per se effect on renal and cardiac function in rats (Ganesan and Anandan, 2009; Ganesan et al. 2009, Hagar and Al Malki 2014; Hagar et al., 2015). Therefore, betaine per se group was not employed in the present study.
Protective Effect of Azadirachta indica and Vitamin E Against Arsenic Acid-Induced Genotoxicity and Apoptosis in Rats
Published in Journal of Dietary Supplements, 2018
Ademola Adetokunbo Oyagbemi, Temidayo Olutayo Omobowale, Olufunke Eunice Ola-Davies, Olumuyiwa Abiola Adejumobi, Ebunoluwa Rachael Asenuga, Funmilola Kehinde Adeniji, Adeolu Alex Adedapo, Momoh Audu Yakubu
Previous studies showed that arsenite induced oxidative DNA adducts and DNA-protein cross-links, which are prerequisites for cancer development through intracellular reactive oxygen species (ROS) or reactive nitrogen species (RNS) generation (Lin, Zhang, & Zhu, 2008). In mammalian cells, arsenite-induced mitochondrial damage has been demonstrated to play a crucial role in the accumulation of ROS leading to arsenic mutagenicity (Saha et al., 2016). This is an indication that sodium arsenite toxicity causes an imbalance between oxidants and antioxidant production. In this study, the observable decreases in markers of oxidative stress (MDA/LPO, nitric oxide [NO], hydrogen peroxide generation) in rats pretreated with Azadirachta indica in arsenic-induced hepatotoxicity show the antioxidant activity of Azadirachta indica. This study also corroborates the hepatoprotective, antioxidant, and free radical–scavenging activities of Azadirachta indica that have been documented elsewhere (Hossain et al., 2014; Upreti, Ali, & Basir, 2013; El-Sayed et al., 2011; Boeke et al., 2004; Yanpallewar et al., 2003).