Neuroprotective Effects of Lacosamide and Memantine on Hyperoxic Brain Injury in Rats.

In neonates supraphysiological oxygen therapy has been demonstrated to cause neuronal death in hippocampus, prefrontal cortex, parietal cortex, and retrosplenial cortex. There is a need for the detection of novel neuroprotective drugs. Neuroprotective effects of lacosamide or memantine have been demonstrated in adult patients with ischemia, trauma and status epilepticus. The effects in immature brains may be different. This study aimed to evaluate neuroprotective effects of lacosamide and memantine treatment in a hyperoxia-induced brain injury model in immature rats. This study was performed in the Animal Experiments Laboratory of Dokuz Eylul University Faculty of Medicine. Neonatal Wistar strain rat pups were exposed to hyperoxia (80% oxygen + 20% nitrogen) for five days postnatally. They were divided into five groups; hyperoxia + lacosamide, hyperoxia + memantine, hyperoxia + lacosamide and memantine, hyperoxia + saline, control groups. After termination of the experiment, brain tissues were examined. Neuron counting in examined regions were found to be higher in hyperoxia + memantine and hyperoxia + lacosamide and memantine groups than hyperoxia + saline group. The presence of apoptotic cells evaluated with TUNEL and active Caspase-3 in hyperoxia + memantine and hyperoxia + lacosamide and memantine groups were found to be lower compared to hyperoxia + saline group. This study demonstrates that neuron death and apoptosis in newborn rat brains after hyperoxia is reduced upon memantine treatment. This is the first study to show the effects of memantine and lacosamide on hyperoxia-induced damage in neonatal rat brains.

The effects of perinatal steroid therapy on growth factor levels during different stages of the developing brain.

OBJECTIVE: Excess glucocorticoid (GC) exposure on the fetal brain during critical stages of development has considerable effects on the development of the central nervous system (CNS). This study thus aimed to evaluate the differential effects of GC exposure on critical growth factor levels during different stages of brain maturation. METHODS: For this purpose, forty-two rat pups were divided into six groups based on the timing of betamethasone administration. Rats in the treatment groups were exposed to intraperitoneal betamethasone injections beginning at different time points (postnatal days 1, 2, and 3). Rats in the placebo group received the same volume of 0.9% saline via the same fashion. Pups were sacrificed at 24 h following the final injection for determining the neuronal density and immunohistochemical evaluation of critical growth factors. RESULTS: In the groups treated with betamethasone on postnatal day 1 (P1) and P2, which correspond to 22-24 and 24-28 gestational weeks in humans, the neuronal count in the hippocampal regions was significantly lower than their control groups. However, if steroid therapy was administered on P3, corresponding to 28-32 weeks in humans, no difference was observed between the two groups. Growth factors were affected in different ways depending on the steroid administration time and evaluated region. CONCLUSIONS: The results suggest that the modulating effect of steroids on neuron count and growth factor response depends on the stage of brain development at the time of exposure. Therefore, this may be one of the key determinants affecting the deleterious and beneficial effects of GCs on the CNS.

Bacillus Calmette-Guerín vaccination: a novel therapeutic approach to preventing hyperoxic lung injury.

OBJECTIVE: A growing body of evidence suggests that vaccinations play a role in the normal maturation of the immune system and in both the development and balance of immune regulatory pathways that can impact health later in life. This study aimed to evaluate the effects of Bacillus Calmette-Guerín (BCG) vaccine on the hyperoxia-induced neonatal rat lung injury. METHODS: Four groups were defined as hyperoxia-exposed BCG-vaccinated, hyperoxia-exposed placebo, room air-exposed control and room air-exposed BCG-vaccinated group. The validity of the hyperoxia-induced lung injury model used in this study was confirmed by histological and immunohistochemical test. Gene expression related with cytokine and growth factor was evaluated by real-time reverse transcription polymerase chain reaction. RESULT: The mean alveolar surface area and quantification of secondary crest formation in the oxygen-exposed placebo group was significantly lower than that of the oxygen-exposed BCG-vaccinated group. Compared to the oxygen-exposed placebo group, the oxygen-exposed BCG-vaccinated group showed a significantly decreased alveolar septal fibrosis and smooth muscle actin expression. The expression of genes VEGF, FGF-BP1, IL-13, and NFκB1 (p50) in the lungs of the hyperoxia-exposed BCG-vaccinated group was significantly higher than that of the hyperoxia-exposed placebo group. CONCLUSION: Results suggest that BCG vaccination can protect against neonatal hyperoxic lung injury. These benefits may be interpreted to coincide with its immunomodulatory effects on pro-inflammatory and anti-inflammatory cytokine balance and expression of growth factors.

Zonisamide attenuates hyperoxia-induced apoptosis in the developing rat brain.

Oxygen therapy used in the treatment of perinatal hypoxia induces neurodegeneration in babies with immature antioxidant mechanisms. Zonisamide is a new antiepileptic drug used in childhood intractable seizures. Many studies demonstrated its neuroprotective effects. There is no study evaluating its effect on hyperoxic brain injury. The aim of this study was to investigate the neuroprotective effect of zonisamide on hyperoxia-induced neonatal brain injury. A total of 21 Wistar rat pups were used. The animals were divided into three groups: control group, hyperoxia group, and zonisamide-treated group. The zonisamide-treated group received an intraperitoneal injection of zonisamide. Zonisamide significantly preserved the number of neurons in CA1 and dentate gyrus parts of hippocampus, prefrontal, and parietal cortex. Zonisamide treatment also decreased the number of apoptotic neurons in all examined parts of hippocampus, prefrontal, and parietal cortex. We suggest that zonisamide treatment may be used as a neuroprotective agent in hyperoxic brain injury.

Caffeic acid phenethyl ester prevents apoptotic cell death in the developing rat brain after pentylenetetrazole-induced status epilepticus.

Population-based studies suggest that seizure incidence is highest during the first year of life, and early-life seizures frequently result in the development of epilepsy and behavioral alterations later in life. The early-life insults like status epilepticus often lead to epileptogenesis, a process in which initial brain injury triggers cascades of molecular, cellular, and network changes and eventually spontaneous seizures. Caffeic acid phenethyl ester is an active component of propolis obtained from honeybees and has neuroprotective properties. The aim of this study was to investigate whether caffeic acid phenethyl ester exerts neuroprotective effects on the developing rat brain after status epilepticus. Twenty-one dams reared Wistar male rats, and 21-day-old rats were divided into three groups: control group, pentylenetetrazole-induced status epilepticus group, and caffeic acid phenethyl ester-treated group. Status epilepticus was induced on the first day of experiment. Caffeic acid phenethyl ester injections (30 mg/kg intraperitoneally) started 40 min after the tonic phase of status epilepticus was reached, and the injections of caffeic acid phenethyl ester were repeated over 5 days. Rats were sacrificed, and brain tissues were collected on the 5th day of experiment after the last injection of caffeic acid phenethyl ester. Apoptotic cell death was evaluated. Histopathological examination showed that caffeic acid phenethyl ester significantly preserved the number of neurons in the CA1, CA3, and dentate gyrus regions of the hippocampus and the prefrontal cortex. It also diminished apoptosis in the hippocampus and the prefrontal cortex. In conclusion, this experimental study suggests that caffeic acid phenethyl ester administration may be neuroprotective in status epilepticus in the developing rat brain.

Effects of pentoxifylline on gentamicin-induced nephrotoxicity.

We aimed to investigate the underlying mechanisms responsible for the renoprotective effects of pentoxifylline (PTX) in gentamicin (GEN)-induced nephropathy. On this purpose, 26 female Wistar rats (200-250 g) were included and four groups were formed. The first one was the control group (n:5). The rats in other groups (n:7 for each) received 50 mg/kg twice daily intraperitoneal (i.p.) PTX, 100 mg/kg i.p. GEN and both GEN and PTX at the same doses for consecutive 8 days, respectively. Rats were weighed both at the beginning and end of the study. After the last dose, 24-hour urines were collected and the rats were sacrificed. Blood samples and kidney tissues were obtained for biochemical, histological, oxidative stress, and apoptotic parameters. Body weights were similar in all groups at the beginning of the study. Rats in GEN group had significant weight loss, tubular damage, and increased apoptosis, while GEN + PTX group had significantly better outcomes. Scr, urinary protein/creatinine, and TBARS levels were significantly higher and Ccr and SOD levels were significantly lower in GEN and GEN + PTX groups in comparison to control and PTX groups, but the levels were similar between GEN and GEN + PTX groups. In conclusion, concomitant administration of PTX provides renoprotection via suppressing apoptosis in GEN-induced nephropathy.

Erythropoietin prevents lymphoid apoptosis but has no effect on survival in experimental sepsis.

BACKGROUND: Lymphoid apoptosis in sepsis is associated with poor outcome, and prevention of apoptosis frequently improves survival in experimental models of sepsis. Recently, erythropoietin (EPO) was shown to protect against lipopolysaccharide (LPS)-induced mortality. As cecal ligation and puncture (CLP) is a clinically more relevant model of sepsis, we evaluated the effect of EPO on CLP-induced lymphoid tissue apoptosis and mortality. METHODS: Young Wistar rats were subjected to polymicrobial sepsis by CLP. EPO (5,000 U/kg intraperitoneal) was administered 30 min before CLP and then 1 and 4 h after CLP. Spleen, thymus, and small intestine were harvested at 24 h and assessed for apoptosis by terminal deoxynucleotidyl transferase nick-end labeling (TUNEL) and caspase-3 staining. A separate group of animals was followed up for mortality. RESULTS: Splenic, thymic, and intestinal apoptosis was increased after CLP; administration of EPO significantly decreased apoptosis as determined by TUNEL and caspase-3 staining. Final survival in the CLP mortality study was 30% in both saline and EPO groups. CONCLUSION: Our results provide the first evidence that EPO attenuates lymphoid apoptosis in the CLP model of sepsis. However, EPO is not associated with a survival benefit in the CLP model of sepsis.

Protective effects of pentoxifylline on lipopolysaccharide-induced white matter injury in a rat model of periventricular leukomalasia.

OBJECTIVE: To investigate the potential neuroprotective effect of maternal pentoxifylline (PNTX) treatment in endotoxin-induced periventricular leukomalasia (PVL) in the developing rat brain. METHOD: Intraperitoneal injection of lipopolysaccharide was administered on two of three Wistar pregnant rats to establish PVL. To obtain PNTX-treated group, one of the two dams were injected with PNTX. The control group was treated with saline. Rat pups were grouped as control, maternal LPS-treated group and PNTX + LPS-treated group. At 7th postnatal days, apoptosis and hypomyelination were evaluated. Apoptosis was evaluated by caspase-3 and terminal deoxynucleotidyl transferase [TdT] dUTP nick endlabelling reaction (TUNEL) immunostaining. To assess hypomyelination, myelin basic protein (MBP) staining, as a marker of myelination, was evaluated. RESULTS: MBP staining was significantly less and weaker in the brains of the LPS-treated group as compared with the PNTX-treated group. PNTX treatment significantly reduced the number of apoptotic cells in the periventricular WM shown on Tunel and caspase-3. CONCLUSIONS: Presented study is first indicated that PNTX may provide protection against an LPS-induced inflammatory response and WMI in the developing rat brain. Our results also suggest that PNTX treatment in pregnant women with maternal or placental infection may minimize the risk of PVL and cerebral palsy.

Neuroprotective effect of erythropoietin on nandrolone decanoate-induced brain injury in rats.

Anabolic-androgenic steroids (AAS) are used in the medical treatment of many disorders. Erythropoietin (EPO) is a hematopoietic cytokine that has anti-apoptotic, anti-oxidative, and anti-inflammatory effects. The aim of the present study is to investigate the neuroprotective effects of EPO in the hippocampus, parietal cortex and prefrontal cortex, in brain damage due to nandrolone decanoate. 35 Wistar male rats were randomly divided into: (1) control group, (2) sham group, (3) nandrolone decanoate group (ND, intramuscular, 10 mg/(kg week), 8 weeks), (4) ND+low dose EPO treated group (ND+L-EPO) and (5) ND+high dose EPO treated group (ND+H-EPO). EPO was administrated by intraperitoneal injection at a dose of 100 U/(kg day) for L-EPO treatment and at a dose of 500 U/(kg day) for H-EPO treatment during 8 weeks. The number of neurons of CA1, CA2, CA3 and dentate gyrus of hippocampus, parietal cortex and prefrontal cortex were significantly less in the ND group compared with the control group. Treatment with H-EPO significantly preserved the number of neurons in hippocampus when compared with ND administrated. Besides, H-EPO treatment decreased the number of TUNEL-positive and active caspase-3 positive cells and MDA levels and increased GPx levels when compared to ND group. In conclusion, abuse of AAS causes reduction in the number of neurons in hippocampus, parietal cortex and prefrontal cortex regions and increases oxidative damage and therefore H-EPO may be useful as a neuroprotective agent in brain injury.

Role of epigenetic regulatory mechanisms in neonatal hypoxic-ischemic brain injury.

BACKGROUND: DNA methylation and histone modifications are the most identified modifications that selectively activate or inactivate genes that control cell growth, proliferation, and apoptosis. AIM: We hypothesized that alterations in gene expression due to hypoxic-ischemic brain damage was regulated by epigenetic mechanisms including DNA methylation and histone methylation. STUDY DESIGN: To test this hypothesis, we established a rat model of HIE. Three groups were defined as hypoxic-ischemic, sham-operated, and control group. OUTCOME MEASUREMENTS: The validity of the HIE model used in this study was confirmed by histological and immunohistochemical tests. Gene expressions related with apoptosis and angiogenesis were studied at 0.5, 3, 6 and 24h after HI or sham operation. DNA and histone methylation status was studied in the genes showing significant change in expression. RESULTS AND CONCLUSIONS: Most of the genes related with apoptosis and angiogenesis (Epo, Epor, Hif 1α, Hif3α, VEGFa, VEGFc, Casp1, Casp9, and Casp8ap2) induced early after HI (30min). All of these genes were unmethylated at the beginning of the insult and in the control group. DNA methylation percentage and histone methylation (H3K36) levels were not correlated with gen expression levels. To our knowledge this is the first study evaluating the role of epigenetic mechanisms in HIE model, therefore the absence of similar studies don't allow us to compare the present results. Further studies investigating different epigenetic mechanisms are needed.

Effects of lipoic acid in an experimentally induced hypertensive and diabetic rat model.

In this study, experimental diabetes and nephrectomy have been applied separately and together in order to investigate the possible therapeutic effects of lipoic acid (LA) on hypertensive and diabetic rat kidneys. Wistar rats were divided into eight groups: control, diabetes mellitus (DM), 5/6 nephrectomy, DM + 5/6 nephrectomy, LA administration, DM + LA treated, 5/6 nephrectomy + LA treated, and DM + 5/6 nephrectomy + LA-treated groups, respectively. Renal damage was evaluated histomorphometrically, ultrastructurally, and biochemically. Our findings supported that diabetes and hypertension together increased the rate of renal injury, and LA had therapeutic effects on hypertensive and diabetic rat kidneys.

Maternal aerobic exercise during pregnancy can increase spatial learning by affecting leptin expression on offspring's early and late period in life depending on gender.

Maternal exercise during pregnancy has been suggested to exert beneficial effects on brain functions of the offspring. Leptin is an adipocytokine which is secreted from adipose tissues and has positive effects on learning, memory, and synaptic plasticity. In this study, pregnant rats were moderately exercised and we observed the effects of this aerobic exercise on their prepubertal and adult offsprings' spatial learning, hippocampal neurogenesis, and expression of leptin. All the pups whose mothers exercised during pregnancy learned the platform earlier and spent longer time in the target quadrant. Their thigmotaxis times were shorter than those measured in the control group. It is shown that hippocampal CA1, CA3 neuron numbers increased in both prepubertal and adult pups, in addition that GD neuron numbers increased in adult pups. Leptin receptor expression significantly increased in the prepubertal male, adult male, and adult female pups. In our study, maternal running during pregnancy resulted in significant increase in the expression of leptin receptor but not in prepubertal female pups, enhanced hippocampal cell survival, and improved learning memory capability in prepubertal and adult rat pups, as compared to the control group. In conclusion, maternal exercise during pregnancy may regulate spatial plasticity in the hippocampus of the offspring by increasing the expression of leptin.

Protective effects of bilirubin in an experimental rat model of pyelonephritis.

OBJECTIVE: To investigate the effects of bilirubin in a rat model of pyelonephritis. METHODS: Experimental pyelonephritis was induced in 32 wistar rats and 4 groups were formed: group 1 (no treatment), group 2 (antibiotic), group 3 (bilirubin), and group 4 (antibiotic + bilirubin). Antibiotic was given on days 3 to 8, and bilirubin was administered between days 0 and 8 of bacterial inoculation. Half of the rats were killed on the 9th day (early period) and histopathological parameters, immunohistochemical renal fibrosis markers, apoptosis, and oxidant/antioxidant system activities were evaluated. The rest of the rats were killed at the 6th week of the study and evaluated for histopathological parameters and renal fibrosis markers. RESULTS: Inflammatory activity was significantly lower in rats treated with antibiotic + bilirubin vs no treatment group both in the early and late periods. In the late period, inflammatory cell intensity was lower in rats treated with bilirubin vs no treatment and the antibiotic + bilirubin groups. Interstitial fibrosis/tubular atrophy was lower in the antibiotic + bilirubin group vs the no treatment and antibiotic groups, and in bilirubin vs antibiotic group. Tissue inhibitor of metalloproteinase-1 expression was lower in the bilirubin vs antibiotic group. Terminal deoxynucleotidyl transferase mediated 2'-deoxyuridine, 5'-triphosphate nick end labeling(+) cells were significantly lower in bilirubin and antibiotic + bilirubin groups vs no treatment group. Malondialdehyde levels were significantly lower in the antibiotic + bilirubin vs the no treatment group and superoxide dismutase activity was significantly higher in the antibiotic and antibiotic + bilirubin groups vs the no treatment group. CONCLUSION: Bilirubin may have protective effects on pyelonephritis-associated inflammation in both early and late periods in addition to fibrosis and apoptosis when applied with antibiotics. When used alone, bilirubin may also prevent inflammation (in the late period) and apoptosis.

Maternal prenatal omega-3 fatty acid supplementation attenuates hyperoxia-induced apoptosis in the developing rat brain.

Supraphysiologic amounts of oxygen negatively influences brain maturation and development. The aim of the present study was to evaluate whether maternal ω-3 long-chain polyunsaturated fatty acid (ω-3 FA) supplementation during pregnancy protects the developing brain against hyperoxic injury. Thirty-six rat pups from six different dams were divided into six groups according to the diet modifications and hyperoxia exposure. The groups were: a control group (standard diet+room air), a hyperoxia group (standard diet+80% O2 exposure), a hyperoxia+high-dose ω-3 FA-supplemented group, a hyperoxia+low-dose ω-3 FA-supplemented group, a room air+low-dose ω-3 FA-supplemented+group, and a room air+high dose ω-3 FA-supplemented group. The ω-3 FA's were supplemented as a mixture of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) from the second day of pregnancy until birth. Rat pups in the hyperoxic groups were exposed to 80% oxygen from birth until postnatal day 5 (P5). At P5, all animals were sacrificed. Neuronal cell death and apoptosis were evaluated by cell count, TUNEL, and active Caspase-3 immunohistochemistry. Histopathological examination showed that maternally ω-3 FA deficient diet and postnatal hyperoxia exposure were associated with significantly lower neuronal counts and significantly higher apoptotic cell death in the selected brain regions. Ω-3 FA treatment significantly diminished apoptosis, in the selected brain regions, in a dose dependent manner. Our results suggest that the maternal ω-3 FA supply may protect the developing brain against hyperoxic injury.

Effect of leptin treatment on neonatal hypoxic-ischemic brain injury.

OBJECTIVE: The aim of this study was to investigate the possible neuroprotective and ameliorating effects of leptin treatment in hypoxic-ischemic injury induced neuronal cell death. METHODS: Experimental groups in the study were: sham-operated group, leptin treated hypoxia-ischemia group, and vehicle treated hypoxia-ischemia group. In hypoxia-ischemia group, left common carotid artery was ligated permanently on the seventh postnatal day. Two hours after the procedure, hypoxia (92% nitrogen and 8% oxygen) was applied for 2.5 h. Leptin treatment was injected (intraperitoneally; i.p.) as a single dose immediately after the hypoxia period. Neuronal cell death, neuronal density, and leptin levels were evaluated in both hemispheres 72 h after the hypoxic-ischemic insult. RESULTS: Compared with the hypoxic-ischemia group, the mean leptin levels were higher in the brains of the sham group for both hemispheres. The leptin treatment significantly diminished the number of 'apoptotic cells' in the hippocampal CA1, CA2, CA3, and gyrus dentatus regions in both hemispheres. Leptin treatment significantly preserved the number of neurons in both hemispheres, when compared with the vehicle treated group. CONCLUSION: We conclude that leptin treatment improves neuronal density and decreases apoptosis in the newborn rat with hypoxic-ischemic brain injury.

Neuroprotective effects of recombinant human erythropoietin in the developing brain of rat after lithium-pilocarpine induced status epilepticus.

Status epilepticus triggers a mixture of apoptotic and necrotic cell death within the hippocampus. This neuronal loss may result in the development of epilepsy and cognitive deficits. Erythropoietin mediates a number of biological actions within the central nervous system and has been shown to be neuroprotective. In the present study, we investigated the effects of recombinant human erythropoietin on hippocampus of rat after lithium-pilocarpine induced status epilepticus. Twenty-one dam reared Wistar male rats, 21-day-old were divided into three groups: control group, lithium-pilocarpine induced status epilepticus and lithium-pilocarpine induced status epilepticus and erythropoietin treated group. Erythropoietin treated group received recombinant human erythropoietin 10 U/g intraperitoneally 40 min after pilocarpine injection for 5 days. Rats were sacrificed and brain tissues were collected at 5th day of experiment. Neuronal cell death and apoptosis were evaluated. Histopathological examination showed that erythropoietin significantly decreased neuronal cell death in CA1, CA2, CA3 and dentate gyrus regions of hippocampus. It also diminished apoptosis in the CA1 and dentate gyrus regions of hippocampus. In conclusion, erythropoietin may preserve the number of neurons and decrease apoptosis in model of status epilepticus induced by lithium-pilocarpine. This experimental study suggests that erythropoietin administration may be neuroprotective in status epilepticus.

RHAMM Expression in the Rat Endometrium during the Estrous Cycle and following Implantation.

BACKGROUND: Receptor for hyaluronic acid mediated motility (RHAMM) has intracellular and extracellular functions. In this study, we focus on the expression of RHAMM in the rat uterus during estrous cycle and implantation period. METHODS: The female adult rats were divided into six groups following estrous cycle determination (n = 36). The utreri of rats were collected according to estrous cycle phases (menstruation group). For the implantation groups, uteri were obtained on D4, D5 and D6 (day of implantation) of pregnancy. The tissue samples were fixed and cut into 5 µm thick sections. RHAMM was investigated using immunohisto-chemical techniques and the intensity of RHAMM was evaluated by using the H-score technique. Comparisons between groups were performed using Kruskal-Wallis test. RESULTS: The RHAMM immunoreactivity of uterine antimesometrial epithelium (343.00±12.81), mesometrial subepithelium (285.00±27.26) and mesometrial stroma (270.00±36.00) were more prominent (p < 0.05) in the proestrus than estrus (275.00± 25.96; 220.00±14.48; 218.00±11.19) and diestrus (262.00±20.71; 192.50± 29.25; 216.00±12.97) groups, respectively. The most intense staining was seen in the epithelium on day four (275.50±30.06) and six (293.50±34.47) of pregnancy (p < 0.05). Strong RHAMM expressions were in both mature and predecidual cells on D5 (256.00±18.71), (247.50±22.14) and D6 (256.00±30.72), (265.00±14.87), respectively. RHAMM expression was prominent in the nondecidual region on D5 (270.00± 13.36). CONCLUSION: Considering the role of RHAMM in cell proliferation, differentiation and angiogenesis, spatiotemporal expression of RHAMM in the uterus during estrous cycle and peri-implantation period is a means through which uterus becomes receptive for developing an embryo.

The effect of Rho kinase inhibitor Y-27632 on endotoxemia-induced intestinal apoptosis in infant rats.

The aim of this study was to evaluate the effect of Rho kinase inhibitor, Y-27632 on the intestinal apoptosis in endotoxemic infant rats. Wistar albino 15-17-day-old rat pups (n = 21) were randomized to three experimental groups: (1) controls; (2) endotoxemia (LPS); and (3) endotoxemia treated with Y-27632 (LPS + Y-27632). Endotoxemia was induced in rats by intraperitoneal (i.p) injection of lipopolysaccharide (Escherichia coli serotype 0111:B4; 10 mg/kg). Y-27632 was administered 5 mg/kg i.p at three times, just, 8 and 16 h after LPS injection. Twenty-four hours after LPS injection, intestinal apoptosis was assessed by hematoxylin and eosin staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay and immunohistochemistry for active caspase-3. Endotoxemia induced extensive apoptotic injury in the intestinal tissues. The administration of Y-27632 to endotoxemic infant rats caused a marked decrease in the number of apoptotic cells in both intestinal epithelium and lamina propria. In conclusion, the inhibition of Rho kinase with Y-27632 diminished the intestinal apoptotic damage induced by endotoxemia in infant rats.

Effects of neotrofin on neonatal hypoxic ischemic brain injury.

Hypoxia-ischemia is a major cause of perinatal brain injury in the newborn. Neotrofin, a neurotrophin agonist, has been shown to provide neuroprotection in several in vivo and in vitro studies. The aim of this study is to investigate the neuroprotective and ameliorating effects of neotrofin treatment after hypoxic-ischemic-injury-induced neuronal cell death, apoptosis in a neonatal hypoxic-ischemic brain injury rat model. Twenty-one seven-day-old Wistar rat pups were used in this study. The groups were: (1) a neotrofin-treated hypoxic-ischemic-group, (2) a saline-treated hypoxic-ischemic-group, and (3) a sham-operated group. Rat pups were subjected to left carotid artery occlusion followed by 2.5h of hypoxic exposure. After the hypoxic exposure, group one received an intra-peritoneal injection of neotrofin at a dose of 60mg/kg. Forty-eight hours after hypoxia, the animals were killed for histopathological evaluation to detect apoptosis and density of neurons. We found that neotrofin attenuates hypoxia-ischemia induced with neuronal density of the hippocampus, the prefrontal and the parietal cortex, and decreased apoptotic cell index in the same regions. Given our results, neotrofin may be useful in reducing brain injury; it possesses clinical relevance for the treatment of hypoxic-ischemic encephalopathy in the newborn.

Esterified hyaluronic acid improves cartilage viability in experimental tracheal reconstruction with an auricular graft.

OBJECTIVE: The aim of this study was to determine the efficacy of esterified hyaluronic acid (HYAFF) on the vitality of auricular cartilage grafts used for tracheoplasty, with respect to macroscopic and microscopic parameters. STUDY DESIGN: Prospective, controlled. SETTING: Academic research laboratory. SUBJECTS AND METHODS: The study included 14 New Zealand rabbits acquired specifically for the study. The rabbits were divided into two groups: the control group, in which free cartilage grafts were not exposed to any materials or additional procedures (n = 7), and the hyaluronic acid (HA) treatment group, in which auricular grafts and anastomosis lines were covered with HYAFF (n = 7). Free auricular cartilage grafts used for the reconstruction of experimentally created tracheal defects were anastomosed extraluminally. All the rabbits were sacrificed two months post surgery. Samples were collected and examined histopathologically. The sections were stained with hematoxylin-eosin, Masson's trichrome, and inducible nitric oxide synthase (iNOS) and examined under a light microscope. RESULTS: Fibrosis and cartilage mass significantly differed between the control and HYAFF group (P < 0.05). Immunohistochemical examination showed that more chondrocytes stained with iNOS in the control group than in the HYAFF group, according to histologists' observations. CONCLUSION: HYAFF catalyzed wound healing with less fibrous tissue formation, had chondroprotective and stimulatory effects on chondrocyte metabolism, and decreased nitric oxide production and apoptosis via improving the nourishment of free auricular cartilage grafts, subsequently preventing hypoxia and oxidative stress, particularly in the early postimplantation period.