Table 2.
Studies of MgSO4 for preterm and term-equivalent neuroprotection reporting no improvement in histological and/or functional outcomes.
| References | Species | Insult | Regime | Timing | Serum levels | T° | Pathology | Function | Survival | Sex | Random-ization/blinding |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (16) | Fetal rat e17 | Maternal LPS | 270 mg/kg bolus + 27 mg/kg maintenance + BM s.c. | +30 min – 4 h | ? | ? | None | No effect on motor function at P13 despite improvements at P5 and P9 in ♂LPS+MgSO4 vs. ♂LPS+vehicle | P 5, 9, 13 | ♀♂ | ✓/? |
| (20) | Fetal mice, e15 | Maternal Mifepristone (RU486) | 270 mg/kg bolus + 27 mg/kg maintenance, + 270 mg/kg bolus, maternal s.c | 0 h | ? | ? | No change in S100B protein expression | None | 4–6 h post RU486 | ? | ✓/? |
| (28) | Fetal mice, e15 | Maternal LPS | 270 mg/kg bolus + 27 mg/kg maintenance, + 270 mg/kg bolus, maternal s.c | 0 h | ? | ? | No effect on inflammatory, oligodendrocyte and astrocyte gene expression. ↑ Caspase-1 and IL-1β mRNA expression in LPS+MgSO4 vs. vehicle+MgSO4 | None | 6 h post LPS | ? | ✓/? |
| (26) | Rat, P7 | HI+8% O2 60 min | 1.1 mg/g i.p. | −3 h, −30 min | 3.3 mmol/L | Ambient: 36°C during hypoxia and 10 min recovery, data not shown | No differences between groups for injury score and % tissue loss vs. vehicle+HI | None | 7 d | ♀♂ | ✓/? |
| (26) | Rat, P7 | HI+8% O2 60 min | 1.1 mg/g i.p. | 1 h | 3.3 mmol/L | Ambient: 36°C during hypoxia and 10 min recovery, data not shown | No differences between groups for injury score and % tissue loss vs. vehicle+HI | None | 7 d | ♀♂ | ✓/✓ |
| (29) | Fetal sheep 0.7 gestation | 25 min UCO | 160 mg loading, 48 mg/h/24 then 24 mg/h/24 h | −24–+24 | 1.9 ± 0.1 mmol/L | Brain: 39-39.6°C, continuous monitoring | ↑oligodendrocyte loss. No effect on neuronal survival | ↓seizure number and burden | 3 d | ♂♀ | ✓/✓ |
| (30) | P1 piglets | Bilateral CAO+FiO2 6% | 180 mg/kg loading then 8 mg/kg/h 48 h + HT vs. vehicle+HT | 1 h | 1.5 mmol/L | Core: normothermia: 38–39 vs. HT: 33.5–34°C, continuous monitoring | No regional improvements in cell death or oligodendrocyte survival. !!! ↓ in total cell death and ↑ oligodendrocyte survival in MgSO4+HT vs. vehicle+HT | No overall improvement in recovery of EEG or MRS markers of outcome!!! Secondary analysis suggested ↑ recovery of aEEG when mild cases were excluded | 2 d | ♂ | ✓/✓ |
CAO, Carotid artery occlusion; EEG, electroencephalography; e, embryonic day; g.a, gestational age; HI, hypoxia ischemia; HT, hypothermia; LPS, lipopolysaccharide; MRS, magnetic resonance spectroscopy; P, postnatal day; T°, temperature; Tx, treatment; UAO, uterine artery occlusion; UCO, umbilical cord occlusion.