Oxidative Biochemistry Disbalance and Changes on Proteomic Profile in Salivary Glands of Rats Induced by Chronic Exposure to Methylmercury

Abstract

Methylmercury (MeHg) is one of the most toxic mercury species, which can cause many systemic damages, but little is known about its effect in the salivary glands. This study aimed to analyze the mercury levels, oxidative stress, and proteomic profile in parotid, submandibular, and sublingual salivary glands of rats, after chronic MeHg intoxication. Two groups of twenty male Wistar rats (90 days of age) were used on the experiment. MeHg group was intoxicated by intragastric gavage with MeHg at a dose of 0.04 mg/kg/day for 60 days, while the control group received only oil. After the period of intoxication, the glands were collected for evaluation of total mercury levels, proteomic profile, and oxidative balance by analyzing the antioxidant capacity against peroxyl radicals (ACAP), lipid peroxidation (LPO), and nitrite levels. Our results have showed that mercury levels were significant in all three glands compared to the respective control. It also showed lower levels of ACAP, as well as higher LPO and nitrite levels. The proteomic profile presented impairments on structural components of cytoskeleton, metabolic pathways, and oxidative biochemistry. Thus, the exposure to MeHg was able to generate oxidative stress that could be associated with changes in the proteomic profile of salivary glands.

Hippocampal Dysfunction Provoked by Mercury Chloride Exposure: Evaluation of Cognitive Impairment, Oxidative Stress, Tissue Injury and Nature of Cell Death

“…Even in this scenario, we chose to administer HgCl 2 by intragastric gavage based on the fact that it represents an important form of intoxication by this metal [ 27 , 28 ], reaching the systemic circulation and possibly crossing the blood-brain barrier and elevating the levels of Hg in neural parenchyma [ 15 ].…”

“…The ability of Hg to inhibit antioxidant enzymes such as glutathione peroxidase, glutathione reductase, superoxide dismutase, and catalase is already known because of its ability to form free and protein-free complexes, which may decrease or inhibit enzymatic activity [ 40 , 43 ]. A recent study by our group revealed that Hg can modulate the ACAP of salivary glands, as it is a sensitive parameter to mercurial exposure [ 27 ].…”

Physical Exercise Attenuates Oxidative Stress and Morphofunctional Cerebellar Damages Induced by the Ethanol Binge Drinking Paradigm from Adolescence to Adulthood in Rats

“…Lipid peroxidation was estimated as the levels of malondialdehyde (MDA) and 4-hydroxyalkenes (4HDA) as earlier detailed by Esterbauer and Cheeseman [30]. As previously described in our studies [5, 31], an aliquot of the supernatant was processed as described by the Bioxytech LPO-568 kit (Cayman Chemical). This kit is a chromogenic reagent that reacts with MDA at 45°C.…”

Omics era in forensic medicine: towards a new age

“…In a study regarding experimental chronic Methylmercury (MeHg) intoxication by intragastric gavage, Bittencourt et al [51], assessed proteomic profile and analyzed mercury levels in rat salivary glands. Their results showed that the exposure to MeHg has strong relationship with alterations in proteomic profile of salivary glands.…”

“…Pittner at al. [44] Pittner et al [45] MS-based proteomics Choi et al [46] Handke et al [47] Procopio et al [49] Prieto-Bonete et al [50] Intoxication and abuse of drugs MS-based proteomics Bittencourt et al [51] Diagnosis of disease and cause of death MS-based proteomics Broadbelt at al. [53] Palmiere et al [54] Immunohistochemistry Unkrig et al [55] Mustafa et al [56] Fineschi et al [57] Edston and van Hage-Hamsten [58] Genomics Detection of the biological specimens PCR Nakanishi et al [12] Postmortem interval PCR Pechal et al [19] Intoxication and abuse of drugs PCR Sallaee et al [62] Ikematsu et al…”