Oral administration of TiO2 nanoparticles during early life impacts cardiac and neurobehavioral performance and metabolite profile in an age- and sex-related manner

Table 1 Concentration (ng/g brain tissue) of neurotransmitters and related metabolites in brain tissue (n = 7–8)

Age at administration	PND 2–5		PND 7–10		PND 17–20
Age at administration	Vehicle	TiO₂ NP	Vehicle	TiO₂ NP	Vehicle	TiO₂ NP
Male
DA²	483 ± 29.7¹	529 ± 34.4*³	507 ± 57.6	530 ± 44.0	493 ± 43.6	423 ± 57.1
DOPAC	129 ± 11.3	134 ± 11.2	111 ± 12.0	149 ± 12.8***	122 ± 14.3	111 ± 17.9
HVA	147 ± 15.3	147 ± 23.5	205 ± 48.1	154 ± 13.6*	288 ± 100	159 ± 47.9*
NE	247 ± 18.6	251 ± 38.4	242 ± 29.8	257 ± 34.9	235 ± 34.1	198 ± 56.6
5-HT	238 ± 57.0	239 ± 60.2	239 ± 47.3	283 ± 28.8	274 ± 52.6	276 ± 36.1
5-HIAA	463 ± 155	489 ± 71.4	471 ± 124	458 ± 19.4	420 ± 50.7	487 ± 78.4
Female
DA	485 ± 28.4	544 ± 41.1***	495 ± 30.2	549 ± 39.1***	508 ± 37.8	466 ± 78.3
DOPAC	127 ± 9.71	135 ± 13.5	116 ± 8.71	149 ± 24.5*	123 ± 7.04	127 ± 26.2
HVA	143 ± 12.0	147 ± 23.5	207 ± 16.2	154 ± 13.4***	266 ± 94.4	172 ± 37.8**
NE	264 ± 40.2	255 ± 37.1	239 ± 33.8	264 ± 29.7	305 ± 26.0	186 ± 44.5***
5-HT	242 ± 46.0	310 ± 68.6	249 ± 48.7	284 ± 27.2	317 ± 41.2	261 ± 46.5
5-HIAA	498 ± 58.4	516 ± 74.9	530 ± 79.9	442 ± 61.7	443 ± 42.9	477 ± 47.1

¹Data is presented as median ± standard deviation
²Dopamine (DA), dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), norepinephrine (NE) (also called noradrenaline (NA) or noradrenalin), serotonin (5-HT), and 5-hydroxyindole-3-acetic acid (5-HIAA)
³Significant differences in concentrations between TiO₂ NP and the corresponding vehicle control is indicated: *P < 0.05, **P < 0.01, and ***P < 0.005

ISSN: 1743-8977