Long-term effects of delayed hyperbaric oxygen therapy on hypoxic-ischemic brain injury in neonatal rats / 中华儿科杂志

<p><b>OBJECTIVE</b>To evaluate the long-term effects of delayed hyperbaric oxygen (HBO) therapy on neonatal rats with hypoxic-ischemic brain injury (HIBD).</p><p><b>METHOD</b>Postnatal 7 days newborn rats (n = 52) were randomly set to three groups: control (n = 18, sham operation), HIBD (n = 17), or HBO (n = 17). Pups in the HBO group were subjected to hyperbaric oxygen treatment with 2 atmosphaera absolutus, 5 x 30 min at a 24 h intervals since 48-72 h after the HIBD model. All the animals were tested for the spatial learning and memory ability in the Morris water maze from postnatal days 37 to 41. At day-42, rats were decapitated and the brains were analyzed for morphological and histological changes, including brain shapes and weights, survival neurons, percentage of AchE positive area and NOS positive neurons in hippocampal CA1 region.</p><p><b>RESULTS</b>Rats in HBO and HIBD groups displayed significant morphological and histological damages, as well as severe spatial learning and memory disability. The average escape latency of Morris water maze in HBO group [(56 +/- 23) s] and HIBD group [(56 +/- 22) s] were longer than the control [(23 +/- 16) s] (P < 0.05). The swimming time in HBO group [(30 +/- 5) s] and HIBD group [(29 +/- 6) s] were shorter than the control [(51 +/- 5) s] (P < 0.05). The swimming length in HBO group [(572 +/- 92) cm] and HIBD group [(548 +/- 92) cm] were shorter than the control [(989 +/- 101) cm] (P < 0.05). The weight of left brains in HBO group [(598 +/- 46) mg] and HIBD group [(601 +/- 59) mg] were lighter than the control [(984 +/- 18) mg] (P < 0.05). The survival neurons of hippocamal CA1 region in HBO group [(97 +/- 27)/mm] and HIBD group [(100 +/- 27)/mm] were less than the control [(183 +/- 8)/mm] (P < 0.05). The percentage of AchE-positive fibers in HBO group [(18.4 +/- 2.2)%] and HIBD group [(18.5 +/- 2.2)%] were less than the control [(27.5 +/- 2.2)%,] (P < 0.05). NOS-positive neurons in HBO group [(21 +/- 5)/mm(2)] and HIBD group [(19 +/- 4)/mm(2)] were also less than the control [(34 +/- 6)/mm(2)] (P < 0.05).</p><p><b>CONCLUSION</b>Delayed HBO therapy resulted in no protection against either HIBD-induced brain morphological and histological deficits or spatial learning and memory disability.</p>

Specific humoral immune responses in rhesus monkeys vaccinated with the Alzheimer's disease-associated beta-amyloid 1-15 peptide vaccine / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Alzheimer's disease (AD) is a neurodegenerative disorder characterized by overproduction of beta-amyloid (Abeta), with the subsequent pathologic deposition of Abeta which is important for memory and cognition. Recent studies showed murine models of AD and AD patients inoculated with Abeta(1-42) peptide vaccine had a halted or delayed pathological progression of AD. Unfortunately, the clinical phase IIa trial of Abeta(1-42) peptide vaccine (AN1792) was halted prematurely because of episodes of menigoencephalitis in 18 of the vaccinated patients. The vaccination of BALB/c or Tg2576 transgenic mouse with Abeta(1-15) peptide vaccine is safe and the immune effects are satisfactory. This study further characterizes the specific humoral immune responses in adult rhesus monkeys induced by Abeta(1-15) peptide vaccine.</p><p><b>METHODS</b>Five male adult rhesus monkeys were injected intramuscularly with Abeta(1-15) peptide vaccine at baseline and at weeks 2, 6, 10, 14, 18 and 22. The titers and IgG isotypes of the antibody against Abeta(1-42) in serum was measured by Enzyme-linked Immunosorbent Assay (ELISA). The specificity of the antibody against Abeta(1-42) was determined by Western blot. The Abeta plaques in Tg2576 transgenic mouse brain were stained with the antiserum using immunohistochemistry method.</p><p><b>RESULTS</b>At the eighth week after the vaccination, antibody against Abeta(1-42) began to develop significantly in serum. The titers of the antibody increased following vaccine boosted and reached 1:3840 at the twenty-fourth week, then decreased after the termination of inoculation. The IgG1 was accounted for the highest level in the antiserum pool. The antibody against Abeta(1-42) showed high specificity. The Abeta plaques in Tg2576 transgenic mouse brain were labeled with the antiserum.</p><p><b>CONCLUSION</b>Abeta(1-15) vaccine can induce vigorously specific humoral immune responses in adult rhesus monkey.</p>