[Effect of rhubarb on neonatal rats with bronchopulmonary dysplasia induced by hyperoxia].

OBJECTIVE: To study the effect of rhubarb on neonatal rats with bronchopulmonary dysplasia (BPD) induced by hyperoxia. METHODS: A total of 64 rats (postnatal day 4) were randomly divided into four groups: air control, rhubarb control, hyperoxia model, and hyperoxia+rhubarb (n=16 each). The rats in the hyperoxia model and hyperoxia+rhubarb groups were exposed to hyperoxia (60% O2) to establish a BPD model. The rats in the rhubarb control and hyperoxia+rhubarb groups were given rhubarb extract suspension (600 mg/kg) by gavage daily. The pathological changes of lung tissue were evaluated by hematoxylin-eosin staining on postnatal days 14 and 21. The content of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) were measured by spectrophotometry. The mRNA and protein expression levels of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) were determined by RT-PCR and Western blot respectively. RESULTS: The hyperoxia model group showed reduced alveolar number, increased alveolar volume, and simplified alveolar structure, which worsened over the time of exposure to hyperoxia. These pathological changes were significantly reduced in the hyperoxia+rhubarb group. On postnatal days 14 and 21, compared with the air control and rhubarb control groups, the hyperoxia model group had significantly reduced radical alveolar count (RAC), significantly reduced activity of SOD in the lung tissue, and significantly increased content of MDA and mRNA and protein expression levels of TNF-α and IL-6 (P<0.05). Compared with the hyperoxia model group, the hyperoxia+rhubarb group had significantly increased RAC, significantly increased activity of SOD in the lung tissue, and significantly reduced content of MDA and mRNA and protein expression levels of TNF-α and IL-6 (P<0.05). CONCLUSIONS: Rhubarb may play a protective role in rats with BPD induced by hyperoxia through inhibiting inflammatory response and oxidative stress.

[Efficacy of hyperbaric oxygen therapy under different pressures on neonatal hypoxic-ischemic encephalopathy].

OBJECTIVE: Some research has shown that hyperbaric oxygen (HBO) can decrease the rate of mortality and disability caused by hypoxic-ischemic encephalopathy (HIE) in neonates. However, the HBO pressure used in the clinical reports and the efficacy of HBO are different. This study was designed to investigate the efficacy of HBO therapy under different pressures by observing the changes of peroxidation, antioxidant levels and brain vasomotor regulation factors as well as the score of neonatal behavioral neurological assessment (NBNA) in neonates with HIE after HBO therapy. METHODS: Sixty neonates with HIE were randomly administered with 1.4, 1.5 or 1.6 atmosphere absolute (ATA) of HBO, once daily for seven days. Serum levels of malondialdehyde (MDA), superoxide dismutase (SOD), nitric oxide (NO) and nitric oxide synthase (NOS) were measured before and after HBO therapy. Meanwhile, NBNA and eye ground examination were performed. RESULTS: Serum SOD level increased and serum levels of MDA, NO and NOS decreased significantly after HBO therapy in the three HBO therapy groups (P<0.01). Serum SOD level was significantly higher and serum levels of MDA, NO and NOS were significantly lower in the 1.6 ATA HBO group than those in the 1.4 ATA group after therapy (P<0.05). The 1.6 ATA HBO group also showed increased SOD and decreased MDA levels compared with the 1.5 ATA HBO group after therapy (P<0.05). NBNA scores in the three groups increased significantly after HBO therapy (P<0.05). None of the three HBO therapy group patients showed abnormal eye grounds after therapy. CONCLUSIONS: HBO therapy with 1.4, 1.5 or 1.6 ATA is safe and effective for neonatal HIE. The antioxidant capacity increases with the increasing HBO pressure in neonates with HIE.