Effects of waterborne cadmium on thyroid hormone levels and related gene expression in Chinese rare minnow larvae

Effects of titanium dioxide nanoparticles on lead bioconcentration and toxicity on thyroid endocrine system and neuronal development in zebrafish larvae

“…A previous study revealed that TH (T 3 and T 4 ) levels in the bloodstream are decreased because of negative feedback from the tshˇ mRNA expression (Manzon and Denver, 2004). Similarly, Li et al (2014) also observed this negative feedback in Chinese rare minnows exposed to Cd, another study explained that the hypothalamic-pituitary-thyroid axis is highly sensitive to toxicant stress during early development . In addition, TTR is important gene for THs, and is exclusively produced and secreted by the choroid plexus in the CNS.…”

“…Li et al (2014) measured the expression of the TH synthesis gene (tg) to explain the mechanisms behind the observed effects on the TH levels; this study showed that heavy metals can alter gene expression in the hypothalamic-pituitary-thyroid axis. In the present study, tg gene expression was significantly altered in both Pb single-exposure and co-exposure groups, indicating that the regulation of tg may reduce the synthesis of THs in the larvae.…”

Transcriptome profiling analysis of rare minnow (Gobiocypris rarus) gills after waterborne cadmium exposure

“…During the acute CdCl 2 treatment period, all fish were fasted, whereas all of the fish in the sub-chronic exposure groups were fed a commercial diet twice a day. Based on a previous study (Li et al, 2014a), one fourth of the water used for the acute and sub-chronic treatments was replaced daily with new water containing the corresponding dose of the contaminant to maintain its concentration. The room temperature was controlled at 25 ± 0.5°C under a 12L:12D artificial photoperiod.…”

Alteration of cytochrome P450 1 regulation and HSP 70 level in brain of juvenile common carp (Cyprinus carpio) after chronic exposure to tributyltin

“…After the total RNA was incubated with deoxyribonuclease I (TaKaRa, Dalian, China), the reverse transcription was performed on 1 lg of total RNA following a PrimeScript TM 1st Strand cDNA Synthesis Kit (TaKaRa, Dalian, China) using the manufacturer's recommended procedure. Levels of CYP450 1 genes (CYP1A, CYP1B, CYP1C1 and CYP1C2) in the fish tissue were determined using quantitative RT-PCR with SYBR Green chemistry on a Rotor-Gene 3000 (Applied Biosystems, USA) using the housekeeping gene b-actin (beta actin mRNA) as internal control according to the method of our laboratory (Li et al 2014). The differences in expression levels were calculated using the 2 -DDCt method (Livak and Schmittgen 2001).…”