–1–
Archives of Toxicology
Developmental exposure to T-2 toxin reversibly affects postnatal hippocampal neurogenesis and reduces
neural stem cells and progenitor cells in mice
Takeshi Tanaka, 1, 2 Hajime Abe, 1, 2 Masayuki Kimura, 1, 2 Nobuhiko Onda, 1 Sayaka Mizukami, 1, 2 Toshinori
Yoshida, 1 and Makoto Shibutani 1,*
1 Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho,
Fuchu-shi, Tokyo 183-8509, Japan
2 Pathogenetic Veterinary Science, United Graduate School of Veterinary Sciences, Gifu University, 1-1
Yanagido, Gifu-shi, Gifu 501-1193, Japan
1 Corresponding author and person to whom reprint requests should be addressed:
Prof. Makoto Shibutani, D.V.M., Ph.D.
Laboratory of Veterinary Pathology,
Tokyo University of Agriculture and Technology
3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan.
Phone: +81-42-367-5771
Fax: +81-42-367-5771
–2–
Supplementary Fig. 1
Overview of the hippocampal formation in a male mouse on postnatal day (PND) 21 stained with hematoxylin
and eosin. The numbers of cells in the hilus of the dentate gyrus (as enclosed by the dotted line) displaying
immunoreactivity for neuron-specific nuclear protein (NeuN), reelin, parvalbumin (PVALB), calbindin-D-28K
(CALB1), calbindin-D-29K (CALB2) were counted. Cornu ammonis (CA) 3 neurons were excluded. NeuN
positive cells were also counted in granule cell layer. (Inset) Higher magnification of the granule cell layer and
subgranular zone (SGZ). The distribution of immunoreactive cells for glial fibrillary acidic protein (GFAP),
brain lipid binding protein (BLBP), paired box 6 (PAX6), T box brain 2 (TBR2), doublecortin (DCX), NeuN,
malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), stem cell factor (SCF) and apoptotic cells, proliferating
cells were measured in the granule cell layer or SGZ. Magnification ×40 (Inset: ×400); bar 400 µm (Inset: 50
µm).
–3–
Supplementary Fig. 2
In life parameters of dams exposed to T-2 toxin from gestation day (GD) 6 to postnatal day (PND) 21 on
weaning of offspring. (a) Body weight. (b) Food consumption. (c) Water consumption. Mean values are plotted.
N = 9–10/group (0 ppm controls, 9; 1, 3, and 9 ppm T-2 toxin, 10). * P < 0.05, ** P < 0.01, significantly
different from 0-ppm controls by the Dunnett’s test or Steel’s test
–4–
Supplementary Fig. 3
The number of immunoreactive cells for neuronal stage-defining markers of granule cell lineages in the
subgranular zone (SGZ), and a mature neuronal marker in the granule cell layer (GCL) of the hippocampal
dentate gyrus of male offspring at PND 21 of the preliminary dose-finding study. (a) Glial fibrillary acidic
protein (GFAP) in the SGZ. (b) Paired box 6 (PAX6) in the SGZ. (c) T box brain 2 (TBR2) in the SGZ. (d)
Doublecortin (DCX) in the SGZ. (e) Neuron-specific nuclear protein (NeuN) in the GCL. Graphs show the
number of immunoreactive cells/unit length (mm) of the SGZ or GCL of the bilateral sides. Values are
expressed as mean + SD. N = 10/group (3 or 4 male offspring per dam). ** P < 0.01, significantly different from
0-ppm controls by Student’s t-test or Aspin-Welch’s t-test. Statistical analysis was performed using the
individual animal as the experimental unit
–5–
Supplementary Table 1
Reproductive parameters, body and organ weights of dams and offspring in the preliminary study T-2 toxin in diet (ppm)
0 (Control) 6 12
Dams at PND 21
No. of animals examined 3 3 3
Reproductive parameters
No. of implantation sites 16.00 ± 2.83a 16.67 ± 1.53 14.67 ± 1.53
No. of live offspring 15.50 ± 2.12 15.00 ± 2.65 10.67 ± 2.31
Body and organ weights at PND 21
Body weight (g) 47.40 ± 4.18 46.53 ± 2.58 45.03 ± 5.57
Brain weight Absolute (g) 0.48 ± 0.01 0.52 ± 0.01 0.50 ± 0.04
Relative (g/100g BW) 1.02 ± 0.07 1.13 ± 0.05 1.12 ± 0.04
Male offspring at PND 21
No. of animals examined 13 16 13
Body and organ weights at PND 21
Body weight (g) 16.58 ± 0.68 13.52 ± 0.42** 12.64 ± 1.80**
Brain weight Absolute (g) 0.44 ± 0.02 0.42 ± 0.01 0.41 ± 0.02**
Relative (g/100g BW) 2.64 ± 0.18 3.24 ± 0.61** 3.28 ± 0.39**
Abbreviations: BW, body weight; PND, postnatal day. a Mean ± SD.
**P < 0.01, significantly different from 0-ppm controls by the Dunnett’s test or Steel’s test. Statistical analysis was
performed using the individual animal as the experimental unit
–6–
Supplementary Table 2
Primary antibodies and experimental conditions used in immunohistochemistry Antigen Abbreviated
name
Host
species
Clonality Clone
number
Dilution Antigen retrieval
condition
Manufacturer
Brain lipid binding
protein
BLBP Rabbit Polyclonal
IgG
n.a. 1:300 None Abcam Inc.
(Cambridge, UK)
Calbindin-D-28K CALB1 Mouse Monoclonal
IgG1
CB-955 1:500 Microwaving, pH 6.0 a Sigma-Aldrich
Chemical Co. (St.
Louis, MO, USA)
Calbindin-D-29K
(Calretinin)
CALB2
Mouse Monoclonal
IgG1
CRT01/
O.N.40
1:100 Microwaving, pH 6.0 LifeSpan Biosciences,
Inc. (Seattle, WA,
USA)
Doublecortin DCX Rabbit Polyclonal
IgG
n.a. 1:1000 None Abcam Inc.
Glial fibrillary
acidic protein
GFAP Mouse Monoclonal
IgG1
GA5 1:200 None Millipore Corporation
(Temecula, CA, USA)
4-Hydroxynonenal 4-HNE Mouse Monoclonal
IgG1
HNEJ-2 1:100 Autoclaving, pH 9.0 b Abcam Inc.
Malondialdehyde MDA Mouse Monoclonal,
IgG2
1F83 1:200 Autoclaving, pH 9.0 Japan Institute for the
Control of Aging
(Shizuoka, Japan)
Neuron-specific
nuclear protein
NeuN Mouse Monoclonal
IgG1
A60 1:100 None Millipore Corporation
Paired box 6 PAX6 Rabbit Polyclonal
IgG1
n.a. 1:200 Autoclaving, pH 6.0 c LifeSpan Biosciences,
Inc.
Parvalbumin PVALB Mouse Monoclonal
IgG1
PARV-1
9
1:1000 Microwaving, pH 6.0 Millipore Corporation
Proliferating cell
nuclear antigen
PCNA Mouse Monoclonal
IgG2a
PC10 1:200 None Dako (Glostrup,
Denmark)
Reelin – Mouse Monoclonal
IgG1
G10 1:1000 None Novus Biologicals,
Inc. (Littleton, CO,
USA)
Stem cell factor SCF Rabbit Polyclonal
IgG
n.a. 1:2000 None Abcam Inc.
T box brain 2 TBR2 Rabbit Polyclonal
IgG
n.a. 1:500 Autoclaving, pH 6.0 Abcam Inc.
a Microwaving at 90 °C for 10 min in 10 mM citrate buffer (pH 6.0). b Autoclaving at 121 °C for 10 min in Target Retrieval Solution (pH 9.0; Dako). c Autoclaving at 121 °C for 10 min in 10 mM citrate buffer (pH 6.0).
–7–
Supplementary Table 3 Primer sequence for real-time RT-PCR analysis Gene Accession No. Forward primer (5' → 3') Reverse primer (5' → 3') Neuronal stage-defining markers in granule cell lineages Pax6 NM_013627 TCCCCAGTCA GACCTCCTCA TA TCATAACTCC GCCCATTCAC T Eomes NM_010136 CTCCCCCCTC CATCAAGTCT TCTCTTGCAA GCGCTGTTGT A Dcx NM_001110222 CTCAGGGAGT GCGCTACAAT TTA GCAGTTCATC CATGCTTCCA AT Interneuron subpopulations Pvalb NM_013645 ATGTCGATGA CAGACGTGCT CAGC TCATCCTCCT CAATGAAGCCA CTTTT Reln NM_011261 CGGCATGTCG TGGTTTCTG GAGTTCCCTT CACATCCTTT GC Cell proliferation maker Pcna NM_011045 GCCTGTTCAC CTAACGTTTG C GGAGACAGTG GAGTGGCTTT TG Intrinsic pathway of apoptosis Bad NM_007522 CCAGCAGCCC AGAGTATGTTC CCCTATCTGT AGCACTAGCG TCTTC Bak NM_007523 CAGCCCTGAA TTTGCGTAGA G CAACAGAACC ACACCAAAAAT CA Bax NM_010921 CGGCGAATTG GAGATGAACT GTCCACGTCA GCAATCATCC T Bcl2 NM_009741 CATGTGTGTG GAGAGCGTCA A GATGCCGGTT CAGGTACTCA GT Bid NM_007544 CAGCCCACAC TGGTGAGACA TCCGACAGGC TGCCATTC Casp2 NM_007610 CTTAGGTCCT CATCTCCGTC TTG CCTCCGCCAG ACTCAAAAAT C Casp3 NM_009810 GCTGGACTGT GGCATTGAGA GGTATCTTCT GGCAAGCCAT CT Casp9 NM_015733 GACAAACTTG AGCACCGATT CC GGCAGTCAGG TCGTTCTTCAC Casp12 NM_009808 CACCAGTCCT CAGACAGCACA T CACCCCACAG ATTCCTTCCA Extrinsic pathway of apoptosis Fadd NM_010175 GCCACACTTG GAGCCCAATA ATCACACCCA GCCAAAGGTT A Tnfsf10 NM_009425 AAAGCTCAAG ATGGAAGGGA AA TGGGAGTAAG ACCCTGGGTT T Tnfrsf10b NM_020275 CGTCTCATGC GGCAGTTG TCGGCTTTGA CCATTTGGA Antioxidant enzymes Gpx1 NM_008160 CGACATCGAA CCTGACATAG A AAC CCAGAGTGCA GCCAGTAATC AC Gpx2 NM_030677 GGCGTCACTC TGAGGAACAA C GCGACATTGC AGCTCATTGA Gpx4 NM_001037741 CTCGCAATGA GGCAAAACTG CGTAAACCAC ACTCAGCATAT CG Sod1 NM_011434 TTTTTGCGCG GTCCTTTC ACCAGAGAGA GCAAGACGAG AAG Sod2 NM_013671 CACACATTAA CGCGCAGATC A GGTGGCGTTG AGATTGTTCA Stem cell regulators Kitl NM_013598 GCAGTAATAG GAAAGCCGCA AA CAATGCCATG GCTGTCCAT Kit NM_001122733 CTTCAGGACC CAAGACGTAA CAG GTGGCGGCTT TGAGTAAATT CTAG Notch1 NM_008714 AACGTGGTCT TCAAGCGTGA T AGCTCTTCCT CGTGGCCATA Glutamate transporters and receptors Slc17a6 NM_080853 TGACAAAGAA TAAGTCCCGT GAAG CATAGTGGAC GAGTGCAGCA AT Slc17a7 NM_182993 GAGGCCAGAT CGCTGACTTT T GAGCTTTCGC ACGTTGGTAG T Gria1 NM_008165 TGCTTCATCA CTCCAAGTTT TCC GGCGCAGCTG AAGGACAA Gria2 NM_013540 AGCCAACAGT TTCGCAGTCA TCGCATAGAC GCCTCTTGAA Gria3 NM_016886 GCAGAGTCCA AACGCATGAA GTGGCAGGAG CAGGCTTAAA Grin2a NM_008170 TCAAACCTGC CCACCTACTC A CGCAGACAGG CATCACACTT Grin2d NM_008172 AGAGCAACAG CTGCAGGTCA T CGCGTAGTCA CTGCCACAA Cholinergic receptors Chrna4 NM_015730 GATTCCGTGC CCTTGATAGC TGAGAGGCCC ACGATGATC Chrna7 NM_007390 CTCGGCCAGT AGCCAATATC TC AATGAGCTGA GCAATCGACA AG Chrnb2 NM_009602 TGTGGACGGT GTACGCTTCA CCTCACACTC TGGTCATCAT CTTC Housekeeping genes for normalization Gapdh NM_008084 TGTCAAGCTC ATTTCCTGGT ATGA TCTTACTCCT TGGAGGCCAT GTA Hprt NM_013556 TTGTATACCT AATCATTATG CCGAGG CAGAGGGCCA CAATGTGATG Abbreviations: Bad, BCL2-associated agonist of cell death; Bak, BCL2-antagonist/killer 1; Bax, Bcl2-associated X protein; Bcl2, B-cell CLL/lymphoma 2; Bid, BH3 interacting domain death agonist; Casp2, caspase 2; Casp3, caspase 3; Casp9, caspase 9; Casp12, caspase 12; Chrna4, cholinergic receptor, nicotinic, alpha polypeptide 4; Chrna7, cholinergic receptor, nicotinic, alpha polypeptide 7; Chrnb2, cholinergic receptor, nicotinic, beta polypeptide 2 (neuronal); Dcx, doublecortin; Eomes (Tbr2), eomesodermin homolog; Fadd, Fas (TNFRSF6)-associated via death domain; Gapdh, glyceraldehyde 3-phosphate dehydrogenase; Gpx1, glutathione peroxidase 1; Gpx2, glutathione peroxidase 2; Gpx4, glutathione peroxidase 4; Gria1, glutamate receptor, ionotropic, AMPA1 (alpha 1); Gria2, glutamate receptor, ionotropic, AMPA2 (alpha 2); Gria3, glutamate receptor, ionotropic, AMPA3 (alpha 3); Grin2a, glutamate receptor, ionotropic, NMDA2A (epsilon 1); Grin2d, glutamate receptor, ionotropic, NMDA2D (epsilon 4); Hprt, hypoxanthine phosphoribosyltransferase; Kit, kit oncogene; Kitl, kit ligand; Notch1, notch 1; Pax6, paired box 6; Pcna, proliferating cell nuclear antigen; Pvalb, parvalbumin; Reln, reelin; RT-PCR, reverse-transcription polymerase chain reaction; Slc17a6, solute carrier family 17 (sodium-dependent inorganic phosphate cotransporter), member 6; Slc17a7, solute carrier family 17 (sodium-dependent inorganic phosphate cotransporter), member 7; Sod1, superoxide dismutase 1, soluble; Sod2, superoxide dismutase 2, mitochondrial; Tnfsf10, tumor necrosis factor (ligand) superfamily, member 10; Tnfrsf10b, tumor necrosis factor receptor superfamily, member 10b.
–8–
Supplementary Table 4
Reproductive parameters, body and organ weights of dams in main study T-2 toxin in diet (ppm)
0 (Control) 1 3 9
No. of dams examined 9 10 10 10
Reproductive parameters
No. of implantation sites 15.30 ± 1.77 a 16.33 ± 1.87 16.15 ± 1.41 15.50 ± 2.65
No. of live offspring 14.36 ± 2.50 14.50 ± 2.07 14.92 ± 1.19 13.75 ± 2.34
Body and organ weights at PND 22
Body weight (g) 45.30 ± 4.38 44.78 ± 1.61 44.71 ± 2.53 45.39 ± 2.92
Brain weight Absolute (g) 0.50 ± 0.03 0.50 ± 0.02 0.49 ± 0.02 0.49 ± 0.02
Relative (g/100g BW) 1.11 ± 0.06 1.11 ± 0.03 1.11 ± 0.05 1.07 ± 0.06
Liver weight Absolute (g) 2.91 ± 0.33 2.89 ± 0.36 2.96 ± 0.24 3.45 ± 0.30**
Relative (g/100g BW) 6.43 ± 0.35 6.45 ± 0.69 6.63 ± 0.46 7.60 ± 0.51**
Thymus weight Absolute (g) 0.09 ± 0.01 0.07 ± 0.02** 0.07 ± 0.02* 0.03 ± 0.01**
Relative (g/100g BW) 0.21 ± 0.03 0.16 ± 0.05* 0.16 ± 0.04 0.07 ± 0.01**
Spleen weight Absolute (g) 0.16 ± 0.03 0.16 ± 0.03 0.21 ± 0.06 0.21 ± 0.09
Relative (g/100g BW) 0.36 ± 0.04 0.35 ± 0.05 0.47 ± 0.13 0.45 ± 0.18
T-2 toxin intake (mg/kg BW/day)
Gestation period 0 0.14 ± 0.02 0.40 ± 0.03 1.18 ± 0.25
Postnatal period 0 0.49 ± 0.03 1.39 ± 0.07 3.79 ± 0.24
Abbreviations: BW, body weight; PND, postnatal day. a Mean ± SD.
*P < 0.05, **P < 0.01, significantly different from 0-ppm controls by the Dunnett’s test or Steel’s test.
–9–
Supplementary Table 5
Histopathological findings of dams T-2 toxin in diet (ppm)
0 (Control) 1 3 9
No. of dams examined 9 10 10 10
Forestomach
Squamous cell hyperplasia 0 a (0/0/0) b 0 (0/0/0) 4 (4/0/0)† 5* (1/2/2)†
Erosion 0 (0/0/0) 0 (0/0/0) 1 (1/0/0) 4 (1/3/0)†
Brain
Abnormalities detected 0 a 0 0 0
Liver
Abnormalities detected 0 0 0 0
Spleen
Extramedullary hematopoiesis 0 (0/0/0) 1 (1/0/0) 1 (0/1/0) 6* (2/3/1)††
Thymus
Atrophy 0 (0/0/0) 1 (1/0/0) 0 (0/0/0) 5* (2/3/0)†
a Total number of animals that exhibited abnormality. b Number of animals with each grade (grade 1/grade 2/grade 3). The degree of abnormalities: grade 1, slight; grade 2,
moderate; grade 3, marked.
*P < 0.05, significantly different from 0-ppm controls by the Fisher’s exact probability test. †P < 0.05, ††P < 0.01, significantly different from 0-ppm controls by the Mann–Whitney’s U-test.
–10–
Supplementary Table 6
Transcript levels in the hippocampal dentate gyrus of offspring on weaning (2) T-2 toxin in diet (ppm) 0 (Control) 9 Relative transcript level normalized to Relative transcript level normalized to Gapdh Hprt Gapdh Hprt
No. of animals examined 6 6 6 6 Neuronal stage-defining markers of granule cell lineages Pax6 1.02 ± 0.19 a 1.01 ± 0.15 1.85 ± 0.78 1.30 ± 0.33* Eomes 1.11 ± 0.49 1.16 ± 0.63 2.75 ± 1.35* 3.22 ± 1.67 Dcx 1.03 ± 0.22 1.04 ± 0.23 2.21 ± 0.77* 1.99 ± 0.98 Interneuron subpopulations Pvalb 1.07 ± 0.44 1.04 ± 0.36 1.27 ± 0.84 0.97 ± 0.48 Reln 1.11 ± 0.57 1.13 ± 0.61 2.68 ± 1.84* 2.09 ± 0.86* Cell proliferation Pcna 1.02 ± 0.21 1.01 ± 0.12 1.45 ± 0.93 1.05 ± 0.26 Stem cell regulators Kitl 1.09 ± 0.52 1.07 ± 0.40 0.58 ± 0.15* 0.52 ± 0.26* Kit 1.05 ± 0.33 1.05 ± 0.33 1.15 ± 0.52 0.98 ± 0.54 Notch1 1.06 ± 0.36 1.04 ± 0.31 1.09 ± 0.23 0.98 ± 0.51 Glutamate transporters and receptors Slc17a6 1.02 ± 0.19 1.00 ± 0.10 0.72 ± 0.33* 0.56 ± 0.26* Slc17a7 1.01 ± 0.19 1.02 ± 0.25 1.05 ± 0.33 0.97 ± 0.66 Gria1 1.01 ± 0.16 1.02 ± 0.23 1.06 ± 0.38 0.98 ± 0.73 Gria2 1.02 ± 0.23 1.01 ± 0.16 0.68 ± 0.14* 0.62 ± 0.31* Gria3 1.04 ± 0.31 1.06 ± 0.38 1.77 ± 0.78 1.43 ± 0.60 Grin2a 1.02 ± 0.23 1.04 ± 0.29 2.11 ± 1.14* 1.61 ± 0.54* Grin2d 1.01 ± 0.20 1.01 ± 0.13 1.47 ± 0.69 1.14 ± 0.39 Cholinergic receptors Chrna4 1.01 ± 0.15 1.01 ± 0.11 0.65 ± 0.33* 0.63 ± 0.40 Chrna7 1.02 ± 0.20 1.03 ± 0.26 1.56 ± 0.68 1.31 ± 0.69 Chrnb2 1.01 ± 0.17 1.01 ± 0.12 0.68 ± 0.19* 0.62 ± 0.31* Antioxidant enzymes Gpx1 1.02 ± 0.23 1.01 ± 0.15 1.46 ± 0.67 1.13 ± 0.20 Gpx2 1.06 ± 0.37 1.03 ± 0.25 1.53 ± 1.00 1.11 ± 0.34 Gpx4 1.02 ± 0.19 1.00 ± 0.08 2.09 ± 1.70 1.50 ± 0.73 Sod1 1.02 ± 0.19 1.00 ± 0.06 1.18 ± 0.51 0.89 ± 0.08 Sod2 1.03 ± 0.27 1.01 ± 0.18 0.98 ± 0.29 0.80 ± 0.28 Intrinsic pathway of apoptosis Bad 1.03 ± 0.24 1.02 ± 0.19 1.23 ± 0.55 0.95 ± 0.19 Bak 1.01 ± 0.14 1.01 ± 0.12 1.01 ± 0.10 0.88 ± 0.33 Bax 1.01 ± 0.14 1.00 ± 0.04 1.53 ± 0.63* 1.32 ± 0.45 Bcl2 1.01 ± 0.12 1.01 ± 0.11 1.23 ± 0.54 0.98 ± 0.30 Bid 1.01 ± 0.13 1.01 ± 0.15 1.13 ± 0.32 0.95 ± 0.32 Casp2 1.01 ± 0.15 1.00 ± 0.08 1.41 ± 0.67 1.07 ± 0.15 Casp3 1.01 ± 0.14 1.00 ± 0.10 1.43 ± 0.61 1.11 ± 0.20 Casp9 1.01 ± 0.13 1.01 ± 0.14 0.91 ± 0.09 0.78 ± 0.32 Casp12 1.04 ± 0.33 1.07 ± 0.46 1.54 ± 1.24 1.10 ± 0.53 Extrinsic pathway of apoptosis Fadd 1.01 ± 0.15 1.00 ± 0.10 1.25 ± 0.10 1.11 ± 0.35 Tnfsf10 1.06 ± 0.38 1.04 ± 0.32 1.37 ± 0.69 1.11 ± 0.37 Tnfrsf10b 1.01 ± 0.13 1.00 ± 0.09 0.99 ± 0.22 0.86 ± 0.23 Abbreviations: Bad, BCL2-associated agonist of cell death; Bak, BCL2-antagonist/killer 1; Bax, Bcl2-associated X protein; Bcl2, B-cell CLL/lymphoma 2; Bid, BH3 interacting domain death agonist; Casp2, caspase 2; Casp3, caspase 3; Casp9, caspase 9; Casp12, caspase 12; Chrna4, cholinergic receptor, nicotinic, alpha polypeptide 4; Chrna7, cholinergic receptor, nicotinic, alpha polypeptide 7; Chrnb2, cholinergic receptor, nicotinic, beta polypeptide 2 (neuronal); Fadd, Fas (TNFRSF6)-associated via death domain; Gapdh, glyceraldehyde 3-phosphate dehydrogenase; Gria1, glutamate receptor, ionotropic, AMPA1 (alpha 1); Gria2, glutamate receptor, ionotropic, Gria3, glutamate receptor, ionotropic, AMPA3 (alpha 3); Grin2a, glutamate receptor, ionotropic, NMDA2A (epsilon 1); Grin2d, glutamate receptor, ionotropic, NMDA2D (epsilon 4); Gpx1, glutathione peroxidase 1; Gpx2, glutathione peroxidase 2; Gpx4, glutathione peroxidase 4; Hprt, hypoxanthine phosphoribosyltransferase; Kit, kit oncogene; Kitl, kit ligand; Notch1, notch 1; Pcna, proliferating cell nuclear antigen; Pvalb, parvalbumin; Reln, reelin; Slc17a7, solute carrier family 17 (sodium-dependent inorganic phosphate cotransporter), member 7; Sod1, superoxide dismutase 1, soluble; Sod2, superoxide dismutase 2, mitochondrial; Tnfsf10, tumor necrosis factor (ligand) superfamily, member 10; Tnfrsf10b, tumor necrosis factor receptor superfamily, member 10b. a Mean ± SD. *P < 0.05, significantly different from 0-ppm controls by the Student’s t-test or Aspin-Welch’s t-test.