Table 1.
Non-comprehensive review of the effects of maternal Trp administration on the physiological and behavioral exhibitions in offspring.
| Species | Treated Time | Control | Treatment | Exhibitions in Offspring | Refs |
|---|---|---|---|---|---|
| Wistar rats | 14 days prior to mating–P4mo * | Standard chow powder (3.5 g Trp/kg) | 10 g Trp mixed with the diet (13.5 g Trp/kg) | Decreased BW of the male offspring at P4mo; Decreased 5-HT concentration, TPH2 activity, and 5-HT uptake in the frontal cortex and brain stem. |
[22] |
| SHRs or DOCA-salt hypertensive rats | 7 continued days prior to mating | Stock chow diet | 30 mg Trp/kg/day mixed with the diet | Increased BW and blood pressure during P5wk–P15wk; Increased brain weight at P20wk; Increased total 5-HT metabolite content (5-HT plus 5-HIAA) in the medulla at P20wk. |
[23] |
| Humans | 210 min | Continued fasting | 1 g Trp orally | Increased incidence of fetal breathing movements; Unchanged breathing rates and breath interval variability. |
[24] |
| SD rats | E17 | Saline vehicle | 200 mg Trp/kg oral gavage | Increased Trp, 5-HT, and 5-HIAA concentrations in the fetal brain at E17 and E18. | [25] |
| SD rats | E15–E21 | Saline vehicle | 200 mg Trp/kg oral gavage | Increased serum PRL at P40d and P70d; Increased serum LH at P70d; Increased forebrain 5-HT and 5-HIAA at P70d. |
[26] |
| Wistar rats | E19 and E21 | 0.1 N-HCl vehicle | 250 mg Trp/kg i.p. | Increased intracerebral concentrations of Trp at E19; Decreased valine, methionine, leucine, tyrosine, phenylalanine, and histidine at E19; Increased phosphoserine, threonine, serine, glutamic acid, and Trp at E21; Decreased methionine, leucine, and histidine at E21; Increased protein synthesis activity indicated by [3H] Leucine incorporation at E19 and E21. |
[27] |
| SD rats | E14.5–late puberty | Control chow (0.22% Trp) | Trp free diet (0.00% Trp) | Dwarfism pups; Decreased serum GH concentration in male and female offspring; Severe hypoprolactinemia; Normal right-timed onset of puberty in both male and female rats. |
[28,29] |
| Wistar rats | E5–E21 | Regular chow diet | Trp-free diet (0.2% Trp) | Unchanged Brain weights in newborn pups; Decreased BW in newborn pups; Reduced numbers of 5-HTergic neurons at the dorsal raphe, especially at the medial and caudal sections of dorsal raphe, which contains the majority of 5-HTergic neurons; Unchanged brain 5-HT concentration. |
[30] |
| SD rats | E1–E21 | Control | 200 mg Trp/kg oral gavage | Increased kidney weight-to-BW ratio at P12wk; Increase blood pressure in male offspring at P4wk, P6wk, P8wk, P10wk, and P12wk; Decreased plasma level of L-citrulline, a precursor of l-arginine and SDMA, an indirect inhibitor of NO synthase; Increased gene expressions in the AHR pathway. |
[31] |
| CKD SD rats | E1–early postnatal life * | Control | 200 mg Trp/kg oral gavage | Decreased systolic blood pressure, mean arterial pressure, and creatinine at P12wk; Decreased plasma level of L-citrulline and SDMA; Altered the abundance of the Trp-metabolizing microbes, i.e., increased the abundance of the genus Intestinimonas and decreased the abundance of Turicibacter. |
[31] |
| SD rats | E1–late puberty | Control rat chow (0.22% Trp) | Trp free diet (0.00% Trp) | Pronounced dwarfism pups; Decreased serum GH concentration in males and females; Marked hypoandrogenism and severe hypoprolactinemia in males; Hypoprolactinemia in females; Right-timed pubertal maturation in both sexes. |
[28,29] |
| SD rats | E1–P12wk * | Control rat chow (0.22 g Trp/100 g of pellets) | high-Trp diet (1 g Trp/100 g of pellets) | Increased blood 5-HT, i.e., hyperserotonemia during P1wk-P12wk; Decreased blood GH; Decreased TPH1 activity in gastrointestinal tracts tissue; Decreased IGF-I expression in hepatic and muscle tissue. |
[32] |
| SD rats | E1–weaning | 500 mg Trp/100 g diet | 75 mg Trp/ 100 g diet | Decreased average BW at weaning; Unaffected opacities at P22d. |
[33] |
| SD rats | E1–P25d * | TD.99366 control diet (1.8 g Trp/kg) | TD.08125 Trp-deficient diet (1 g Trp/kg) | Normal BW at P5d but reduced BW at P15d and P25d; Decreased body temperatures at P15d and P25d; Unaffected Oxygen consumption (VO2); Altered breathing pattern and slower heart rates at 15 d; Decreased ventilation (VE) and VE-to-VO2 ratios in both air and 7% CO2 at P25d; Increased ventilatory response to CO2 at P5d in male offspring and reduced at P15d and P25d in male and female offspring; Reduced medullary 5-HT concentration, while similar 5-HT neuronal number. |
[34] |
| Pigs | Third trimester of gestation–delivery | 2×Trp diet (0.26% Trp fed in the morning and afternoon) | High-low Trp diet (0.39% Trp fed in the morning and 0.13% Trp fed in the afternoon) | Decreased birth healthy pig rate and birth weight of piglet per pen with similar total birth weight per pen; Decreased serum phosphoserine, taurine, cysteine, proline in newborns and increased liver n-6:n-3 PUFA ratio; Altered gene expressions, including the genes related to cytotoxic effector regulation, NADH oxidation, ROS metabolism, and tissue development. |
[35] |
| Outbred CD-1 mice | Lactation (P0d–P8d) | Standard laboratory diet (0.14% Trp) | Trp-deficient diet (0.00% Trp) | Unchanged time spent in open sectors in the 0-maze test in adolescent daughters (P189d–P193d); Unchanged time spent in floating in the forced-swim test in adolescent daughters; Unchanged time spent in the novel compartment in the novelty-seeking test in adolescent daughters; Unchanged achieved breakpoint in the progressive ratio operant procedure in adolescent daughters; Decreased plasma CORT concentrations and similar BDNF concentrations following restraint stress in adolescent daughters. |
[36] |
* The pups are fed the same diet as mothers throughout postnatal life. 5-HIAA: 5-hydroxyindoleacetic acid; 5-HT: serotonin; AHR: aryl hydrocarbon receptor; BDNF: brain-derived neurotrophic factor; BW: body weight; d: day; CKD: chronic kidney disease; CORT: corticosterone; DOCA: deoxycorticosterone acetate; E: embryonic day; GH: growth hormone; IGF-1: insulin-like growth factor-I; i.p.: intraperitoneal; LH: luteinizing hormone; mo: month; NADH: nicotinamide adenine dinucleotide; P: postnatal; PRL: prolactin; PUFA: polyunsaturated fat; SD: Sprague-Dawley; SDMA: symmetric dimethylarginine; SHRs: spontaneously hypertensive rats; TPH: tryptophan hydroxylase; Trp: tryptophan; ROS: reactive oxygen species; wk: week.