4 research outputs found
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Perfluoroalkyl chemicals (PFCs) are stable man-made compounds
with
many industrial and commercial uses. Concern has been raised that
they may exert deleterious effects, especially on lipid regulation.
We aimed to assess exposure to perfluorooctanoic acid (PFOA), perfluorooctane
sulfonic acid (PFOS), and seven other PFCs in occupational workers
from a fluorochemical plant and nearby community residents, and to
investigate the association between PFOA and serum biomarkers. Serum
biomarkers included not only biochemical parameters, such as lipids
and enzymes, but also circulating microRNAs (miRNAs). Samples were
analyzed by high-pressure liquid chromatography/tandem mass spectrometry
(HPLC-MS/MS). Circulating miRNA levels were detected by quantitative
polymerase chain reaction (PCR). Analyses were conducted by correlation
and linear regression. We detected PFOS, PFOA, perfluorohexane sulfonate
(PFHxS), perfluorononanoic acid (PFNA), and perfluorodecanoic acid
(PFDA) in all samples. The median levels of serum PFOA and PFOS were
284.34 ng/mL and 34.16 ng/mL in residents and 1635.96 ng/mL and 33.46
ng/mL in occupational participants, respectively. To our knowledge,
we found for the first time that PFOA was negatively associated with
high-density lipoprotein cholesterol (HDL-C) in workers using linear
regression after adjusting for potential confounders. Circulating
miR-26b and miR-199a-3p were elevated with serum concentration of
PFOA. Although the limitations of small sample size and the cross-sectional
nature of the current study constrained causal inferences, the observed
associations between PFOA and these serum biomarkers warrant further
study
Prenatal and Neonatal Exposure to Perfluorooctane Sulfonic Acid Results in Changes in miRNA Expression Profiles and Synapse Associated Proteins in Developing Rat Brains
We previously identified a number of perfluorooctane
sulfonic acid
(PFOS)-responsive transcripts in developing rat brains using microarray
analysis. However, the underlying mechanisms and functional consequences
remain unclear. We hypothesized that microRNAs (miRNAs), which have
emerged as powerful negative regulators of mRNA and protein levels,
might be responsible for PFOS-induced mRNA changes and consequent
neural dysfunctions. We used eight miRNA arrays to profile the expression
of brain miRNAs in neonatal rats on postnatal days (PND) 1 and 7 with
maternal treatment of 0 (Control) and 3.2 mg/kg of PFOS feed from
gestational day 1 to PND 7, and subsequently examined six potentially
altered synapse-associated proteins to evaluate presumptive PFOS-responsive
functions. Twenty-four brain miRNAs on PND 1 and 17 on PND 7 were
significantly altered with PFOS exposure (<i>P</i> <
0.05), with miR-466b, -672, and -297, which are critical in neurodevelopment
and synapse transmission, showing a more than 5-fold reduction. Levels
of three synapse-involved proteins, NGFR, TrkC, and VGLUT2, were significantly
decreased with no protein up-regulated on PND 1 or 7. Perfluorooctane
sulfonic acid might affect calcium actions during synapse transmission
in the nervous system by interfering with SYNJ1, ITPR1, and CALM1
via their targeting miRNAs. Our results indicated that miRNA had little
direct regulatory effect on the expression of mRNAs and synapse-associated
proteins tested in the developing rat brain exposed to PFOS, and it
seems that the PFOS-induced synaptic dysfunctions and changes in transcripts
resulted from a combinatory action of biological controllers and processes,
rather than directed by one single factor
Global Liver Proteome Analysis Using iTRAQ Labeling Quantitative Proteomic Technology to Reveal Biomarkers in Mice Exposed to Perfluorooctane Sulfonate (PFOS)
Proteomic analysis allows detection of changes of proteins
expression
in organisms exposed to environmental pollutants, leading to the discovery
of biomarkers of exposure and understanding of the action mechanism
of toxicity. In the present study, we applied iTRAQ labeling quantitative
proteomic technology for global characterization of the liver proteome
in mice exposed to perfluorooctane sulfonate (PFOS). This successfully
identified and quantified 1038 unique proteins. Seventy-one proteins
showed a significant expression change in the treated groups (1.0,
2.5, 5.0 mg/kg of body weight) compared with the control group, and
16 proteins displayed strong dose-dependent changes. Gene ontology
analysis showed that these differential proteins were significantly
enriched and mainly involved in lipid metabolism, transport, biosynthetic
processes, and response to stimulus. We detected significantly increased
expression levels of enzymes regulating peroxisomal β-oxidationincluding
long-chain acyl-CoA synthetase, acyl-CoA oxidase 1, bifunctional enzyme,
and 3-ketoacyl-CoA thiolase A. PFOS also significantly induced cytochrome
P450s and glutathione S-transferases that are responsible for the
metabolism of xenobiotic compounds. The expressions of several proteins
with important biological functions–such as cysteine sulfinic
acid decarboxylase, aldehyde dehydrogenase, and apolipoprotein A-I,
also correlated with PFOS exposure. Together, the present results
provide insight into the molecular mechanism and biomarkers for PFOS-induced
effects
Global Liver Proteome Analysis Using iTRAQ Labeling Quantitative Proteomic Technology to Reveal Biomarkers in Mice Exposed to Perfluorooctane Sulfonate (PFOS)
Proteomic analysis allows detection of changes of proteins
expression
in organisms exposed to environmental pollutants, leading to the discovery
of biomarkers of exposure and understanding of the action mechanism
of toxicity. In the present study, we applied iTRAQ labeling quantitative
proteomic technology for global characterization of the liver proteome
in mice exposed to perfluorooctane sulfonate (PFOS). This successfully
identified and quantified 1038 unique proteins. Seventy-one proteins
showed a significant expression change in the treated groups (1.0,
2.5, 5.0 mg/kg of body weight) compared with the control group, and
16 proteins displayed strong dose-dependent changes. Gene ontology
analysis showed that these differential proteins were significantly
enriched and mainly involved in lipid metabolism, transport, biosynthetic
processes, and response to stimulus. We detected significantly increased
expression levels of enzymes regulating peroxisomal β-oxidationincluding
long-chain acyl-CoA synthetase, acyl-CoA oxidase 1, bifunctional enzyme,
and 3-ketoacyl-CoA thiolase A. PFOS also significantly induced cytochrome
P450s and glutathione S-transferases that are responsible for the
metabolism of xenobiotic compounds. The expressions of several proteins
with important biological functions–such as cysteine sulfinic
acid decarboxylase, aldehyde dehydrogenase, and apolipoprotein A-I,
also correlated with PFOS exposure. Together, the present results
provide insight into the molecular mechanism and biomarkers for PFOS-induced
effects