Biotinidase Activity Inhibition as a Biomarker of Effect to Mercury:

Overview

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Key numbers

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• Table 1. Demographic Characteristics of the Four Amazonian Riverside Populations Surveyed in the Present Study and Their
• gender female, % 100 73.2 81.3 59.6
• Figure 1. Prevalence (%) of subjects presenting reduced activity of the BTD enzyme in each of the four study communities analyzed in the
• cofactor for a number of different carboxylase enzymes, aminotransferase (ALT) (Table 2).
• apocarboxylases to form active enzymes.21−23 Table 2. Biochemical Indicators of Liver Function in
• the participants are summarized in Table 1. and mercury exposure, we also collected hair samples from 132
• Barreiras (BRR), and Tucurui ́ Lake (TUC) populations had Table 3.
• Table 4. Profile of Participants According to Hair Mercury
• THg n = 67 THg n = 65 P*
• female 39 (58.20%) 35 (53.84%)
• Table 3. Demographic Characteristics and Biochemical and Hair mercury concentration
• TUCb (n = 132) The parameters are presented as the median and (interquartile
• female, n (%) 87 (59.18%)
• Biotinidase activity decreased by 20% at a MeHg concentration
• of 0.5 μM, 55% at 5 μM, and 82% at 50 μM, reflecting the
• except for biotinidase activity, which is presented as the mean and 2.5. Structural Modeling of Biotinidase
• median hair mercury concentration of 9.28 μg/g (interquartile range: activity, we first obtained the three-dimensional structure of
• mean BTD activity of 3.21 nmol·mL−1·min−1, below the reference biotinidase (Figure 4A) made with Swiss-Model had 91.99% of
• 27.42 μg/g (Table 4). To analyze the possible relationship The docking analysis returned seven results (Table 5). The
• μg/g or ≥10 μg/g) (Table 4). Although we found no analysis indicate that MeHg interacts with Cys245 at a distance
• reduction in the mean BDT activity in the subgroup with lower with increasing MeHg concentrations (Figure 3A) is consistent
• Table 5. Docking Results both its organic and inorganic forms, can inhibit biotinidase
• The investigation of four Amazonian populations revealed hair revealed a median concentration of 9.28 μg/g, reaching
• ranging from 20% at 0.5 μM to 82% at 50 μM. By contrast, gluconeogenesis.31
• (∼40 μg/L) indicate advanced toxicity, manifesting clinical tions.67,72,73 These symptoms may manifest as developmental
• Amazonian riverside communities with very similar lifestyles, with sodium phosphate buffer, 0.1 mM EDTA, and 0.25% BSA, pH 6.5). A
• contaminated fish.6−8,10 30% TCA, after which they were homogenized in a vortex.
• 25 μL of 0.5% ammonium sulfamate, and 25 μL of 0.1% N−1-
• 4CYF was used as the template, with a sequence identity of 44.20%. Phone: +55 91 981269945; Email: barbarella@ufpa.br
• ranges. The data were analyzed with a one-way ANOVA followed by Metabolismo, ICB-UFPA, 66075-110 Belém, PA, Brazil
• nucleophilic thiolate sites: relevance to pathophysiological mecha- potentials (QMEANBrane). Bioinformatics 2014, 30 (17), i505-11.
• (65) Franco, R.; Sánchez-Olea, R.; Reyes-Reyes, E. M. Panayiotidis Haas, J.; Schwede, T. QMEANDisCo-distance constraints applied on

Methods (brief)

• in silico, in vitro, and in vivo in human blood samples. Biotinidase is an enzyme that is
• In the present study, a total of 318 individuals were sampled
• the participants are summarized in Table 1. and mercury exposure, we also collected hair samples from 132
• samples of healthy donors with no known exposure to mercury of endogenous biotin, a substance that is vital for the synthesis
• essential sulfhydryl groups of the enzyme.47−50 Mercury, in with larger sample sizes and additional biomarkers and blood
• sample size in the PNC setting; however, as discussed above, the active domain. This supports the conclusion that MeHg
• biotinidase inhibition as a biomarker reflecting the biological the blood and hair samples.
• monitoring environmentally vulnerable populations. Blood samples were collected from healthy adult volunteers and
• centrifuged at 3000 rpm for 10 min. Each sample was extracted from
• Approximately 1 g of hair samples was collected from the occipital
• described by Wolf et al.21 A sample of 50 μL of serum was incubated
• subsistence being based on fishing and small-scale farming. The blank of each sample was prepared by inactivating the serum in a
• residents of three of these populations (SLT, BRR, and TUC) are water bath at 60 °C for 30 min. The samples were incubated at 38 °C
• The homogenized samples were centrifuged at 3000 rpm for 5 min
• min, the absorbance of the samples was measured using a microplate
• Total mercury concentration was determined in hair samples using a
• For reference, blood samples were collected from healthy donors not followed by Dunn’s post hoc test (nonparametric) to compare groups.
• centrifugation at 3000 rpm for 10 min. Samples of the serum were using the Mann−Whitney test. The P value <0.05 was considered

Implications

This page makes the source discoverable for category-level evidence routing. Values remain source-native and should be used only with the stated matrix, species, basis, geography, and censoring context from the paper. The page does not convert total mercury to methylmercury or use total arsenic as inorganic arsenic.

Wiki pages this source may touch

• Fish — marine, non-predatory (sardines, anchovies, salmon, cod)
• Mercury
• Mercury
• Cadmium
• Chromium

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