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Background: Ferulic acid provides a neuroprotective effect during cerebral ischemia through its anti-oxidant function. Protein phosphatase 2A (PP2A) is a serine and threonine phosphatase that contributes broadly to normal brain function. This study investigated whether ferulic acid regulates PP2A subunit B in a middle cerebral artery occlusion (MCAO) animal model and glutamate toxicity-induced neuronal cell death. Methodology/Principal Findings: MCAO was surgically induced to yield permanent cerebral ischemic injury in rats. The rats were treated with either vehicle or ferulic acid (100 mg/kg, i.v.) immediately after MCAO, and cerebral cortex tissues were collected 24 h after MCAO. A proteomics approach, RT-PCR, and Western blot analyses performed to identification of PP2A subunit B expression levels. Ferulic acid significantly reduced the MCAO-induced infarct volume of the cerebral cortex. A proteomics approach elucidated the reduction of PP2A subunit B in MCAO-induced animals, and ferulic acid treatment prevented the injury-induced reduction in PP2A subunit B levels. RT-PCR and Western blot analyses also showed that ferulic acid treatment attenuates the injury-induced decrease in PP2A subunit B levels. Moreover, the number of PP2A subunit B- positive cells was reduced in MCAO-induced animals, and ferulic acid prevented these decreases. In cultured neuronal cells, ferulic acid treatment protected cells against glutamate toxicity and prevented the glutamate-induced decrease in PP2A subunit B. Conclusions/Significance: These results suggest that the maintenance of PP2A subunit B by ferulic acid in ischemic brain injury plays an important role for the neuroprotective function of ferulic acid. [ABSTRACT FROM AUTHOR]

Hepatic ischemia-reperfusion (I-R) injury induces hepatic dysfunction or failure. Melatonin is a potent free radical scavenger and a strong antioxidant. Although many studies have demonstrated the protective effect of melatonin in hepatic injury, the molecular mechanisms of this protection are unclear. We identified specific proteins that are differentially expressed by melatonin treatment in hepatic I-R injury. Adult mice were subjected to 1 hr of ischemia and 3 hr of reperfusion. Animals were treated with vehicle or melatonin (10 mg/kg, i.p.) 15 min prior to ischemia and just before reperfusion. Serum aspartate aminotransferase and alanine aminotransferase levels were higher in I-R group than in sham-operated group, and these increases were reduced by melatonin treatment. Proteins that were differentially expressed following melatonin treatment during hepatic I-R injury were detected using two-dimensional gel electrophoresis. Hepatic I-R injury induced down-regulation of glyoxalase I, glutaredoxin-3, spermidine synthase, proteasome subunit beta type-4, and dynamin like protein-1 (DLP-1). However, melatonin prevented the reductions in these proteins induced by I-R injury. Among the identified proteins, we focused on DLP-1, which is essential for the maintenance of mitochondrial and endoplasmic reticulum morphology. Western blot analysis confirmed that melatonin prevents the hepatic I-R injury-induced decrease in DLP-1. These results suggest that melatonin protects hepatic cells against hepatic I-R injury and that its protective effects involve the regulation of specific proteins. [ABSTRACT FROM AUTHOR]

A standardized extract of Gingko biloba, EGb 761, has been shown to exert a neuroprotective effect against permanent and transient focal cerebral ischemia. This study investigated whether EGb 761 modulates Bcl-2 family proteins in ischemic brain injury. Male adult rats were treated with EGb 761 (100 mg/kg) or vehicle prior to middle cerebral artery occlusion (MCAO), brain tissues were collected 24 hours after MCAO. EGb761 administration significantly decreased the number of TUNEL-positive cells in the cerebral cortex. Ischemic brain injury induced decrease of Bcl-2 and Bcl-XL levels. EGb 761 prevented not only the injury-induced decrease of Bcl-2 and Bcl-XL levels, but also the injury-induced increase of Bax. Moreover, in the presence of EGb 761, the interaction of Bad and Bcl-XL decreased compared to that of vehicle-treated animals. In addition, EGb 761 prevented the injury-induced increase of cleaved PARP. The finding suggests that EGb 761 prevents cell death against ischemic brain injury and EGb 761 neuroprotection is affected by preventing the injury-induced increase of Bad and Bcl-XL interaction. [ABSTRACT FROM AUTHOR]

It has recently been reported that melatonin protects neuronal cells from damage by enhancing Akt activation, thus mediating antiapoptosis signals. However, there is little information regarding the effects of melatonin on the activation of genes further downstream in the Akt signaling pathway in ischemic brain injury. This study investigated whether melatonin modulates the antiapoptotic signal through Akt and its downstream targets, Bad and 14-3-3. Adult male rats were treated with melatonin (5 mg/kg) prior to middle cerebral artery occlusion (MCAO). Brains were collected at 24 hr after MCAO and infarct volumes were analyzed. Our results confirm that melatonin significantly reduces infarct volume and decreases the positive reaction of TUNEL staining in the cerebral cortex. Signal pathway activation was measured by phosphorylation of Akt at Ser473 and Bad at Ser136 using Western blot analysis. Melatonin prevented the injury-induced decrease of pAkt and pBad levels. However, melatonin did not affect the expression of 14-3-3, which acts as an antiapoptotic factor through interaction with Bad. Immunoprecipitation analysis showed that the interaction between pBad and 14-3-3 increased in the presence of melatonin, compared to that of control animals. Our findings suggest that melatonin prevents cell death because of brain injury and that these protective effects are mediated through maintaining the interaction between pBad and 14-3-3, thus blocking activation of the apoptotic pathway. [ABSTRACT FROM AUTHOR]

Several growth factors are critical regulators of testicular development Recently. pituitary adenylate cyclase-activating polypeptide (PACAP) has been shown to promote the differentiation and proliferation of various cell types and to stimulate the release of vascular endothelial growth factor during tissue growth. The present study aimed to evaluate the possible expression of PACAP in immature and adult rat testes by Northern blot analysis, in situ hybridization, and immunohistochemistry. PACAP transcripts were detected in both immature and adult tissues, but the level of PACAP expression depended on the age of the animal. It was expressed in the peritubular and interstitial cells of the 14-day-old testis and in seminiferous tubules of the 90-day-old-testis. It was strongly expressed in blood vessels at 14 days. moderately at 28 days and only weakly at 90 days. These results suggest that PACAP contributes to the growth and differentiation of peritubular and interstitial tells, and of blood vessels, during testicular development. [ABSTRACT FROM AUTHOR]

The production of a steroid hormone in the placenta is essential for maintaining the pregnancy and developing the fetus during gestation. In various steroidogenic tissues (including gonads and adrenal cortex), the steroidogenic-acute-regulatory protein (StAR) acutely transfers cholesterol from the outer to the inner mitochondrial membrane for rapid steroidogenesis. Although steroid hormones were synthesized in the rat placenta, the developmental expression of StAR has been poorly understood in the rat placenta during mid-late pregnancy. Therefore, the aim of the present study was to establish the expression and localization of StAR mRNA in the rat placenta during mid-late pregnancy using Northern blots and in situ hybridization. The Northern blot analysis showed that the StAR mRNA expression significantly changed as the gestation day (GD) progressed. The placental expression of StAR mRNA increased between GD 11 and 13, and then slightly decreased until term. n situ hybridization showed a strong StAR expression in giant trophoblast cells on GD 11 and 13, and a moderate expression in trophoblast and stroma cells within the villi of the labyrinth zone throughout the pregnancy. In this study, we reveal for the first time the existence of StAR mRNA in steroidogenic cells of the placenta during mid-late pregnancy. In conclusion, our results suggest that StAR may regulate steroidogenesis in the rat placenta to maintain the pregnancy and developing the fetus. [ABSTRACT FROM AUTHOR]

Presents information on a study which evaluated the expression of dopamine (DA) D[sub 1] and D[sub 2] receptor messenger RNA (mRNA) in systemic and pulmonary vasculatures. Details on in situ hybridization; Localization of DA receptor mRNA in the systemic arteries and superior vena cava; Localization of DA receptor mRNA in the pulmonary artery and vein.

We previously reported that melatonin protects neuronal cells against ischemic brain damage. In this study, we identified proteins that were differentially expressed by melatonin treatment during ischemic brain injury. Rats were subjected to cerebral ischemia by middle cerebral artery occlusion (MCAO). Adult male rats were treated with melatonin (5 mg/kg) or vehicle prior to MCAO and brains were collected at 24 hr after MCAO. Proteins derived from the cerebral cortex were analyzed using two-dimensional gel electrophoresis. Protein spots with a greater than 2.5-fold change in intensity were identified by mass spectrometry. Among these proteins, γ-enolase, stathmin, thioredoxin, peroxiredoxin-6, hippocalcin, protein phosphatase 2A, adenosylhomocysteinase, ubiquitin carboxy-terminal hydrolase L1, and NAD-specific isocitrate dehydrogenase subunit α were significantly decreased in the vehicle-treated group in comparison to the melatonin-treated group. The identified proteins consist of cell differentiation and stabilization proteins, as well as an antioxidant enzyme. In contrast, dehydroprimidinase-related protein 2 (DRP-2), a target of protein oxidation in neurodegeneration, was significantly increased in vehicle-treated animals, while melatonin prevented the injury-induced increase of DRP-2. Thus, the results of this study suggest that melatonin prevents cell death resulting from ischemic brain injury and that its neuroprotective effects are mediated by both the up- and down-regulation of various proteins. [ABSTRACT FROM AUTHOR]