https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 Protective mechanism of testosterone on cognitive impairment in a rat model of Alzheimer's disease https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:45031 Wed 26 Oct 2022 10:52:42 AEDT ]]> The protective mechanism underlying phenylethanoid glycosides (PHG) actions on synaptic plasticity in rat Alzheimer's disease model induced by beta amyloid 1-42 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36237 Tue 17 Mar 2020 12:25:30 AEDT ]]> The protective mechanism underlying total flavones of Dracocephalum (TFD) effects on rat cerebral ischemia reperfusion injury https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36238 Tue 17 Mar 2020 12:25:30 AEDT ]]> Effects of testosterone on synaptic plasticity mediated by androgen receptors in male SAMP8 mice https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:25302 Sat 24 Mar 2018 07:30:19 AEDT ]]> Effects of testosterone treatment on synaptic plasticity and behavior in senescence accelerated mice https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:23032 Sat 24 Mar 2018 07:13:48 AEDT ]]> Inhibition of oxidative stress by testosterone improves synaptic plasticity in senescence accelerated mice https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:46652 p-NMDAR1) and (3) phosphorylated calmodulin-dependent protein kinase II (p-CaMKII). In addition, the content of whole brain malondialdehyde (MDA) as well as activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were determined. Treatment with T significantly elevated the number of intact pyramidal cells in hippocampal CA1 region and markedly increased hippocampal protein and mRNA expression levels of p-NMDAR1 and p-CaMK II. Further, T significantly decreased whole brain MDA levels accompanied by elevated activities of SOD and GSH-Px. Data suggest that the protective effects of T on synaptic plasticity in a mouse AD model may be associated with reduction of oxidant stress.]]> Mon 28 Nov 2022 17:29:45 AEDT ]]> Mechanisms associated with protective effects of Ginkgo biloba leaf extracton in rat cerebral ischemia reperfusion injury https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:46651 Ginkgo biloba leaf extract (GbE) is composed predominantly of active ingredients such as flavonoids and terpene lactones and often used to treat cerebrovascular diseases. However, the mechanisms underlying the use of this herbal extract to treat cerebrovascular-mediated damage are not known. The aim of this study was to examine the effectiveness of administration GbE to ameliorate the observed consequences of CIRI. The following parameters were measured: (1) behavioral score (2) infarct area (3) the content of serum malondialdehyde (MDA) as well as activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and (4) interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF-a) expression levels in the infarcted brain tissue. Data demonstrated that treatment with GbE to CIRI rats resulted in significant reduction in cerebral-infarcted area associated with improvement in behavioral score. GbE was found to decrease serum MDA levels concomitant with elevated activity levels of SOD and GSH-PX. Immunohistochemistry and Western blot analysis showed that GbE significantly lowered the levels of IL-6 and TNF-a in the infarcted brain tissue. Data suggest that GbE may be therapeutically effective in improving behavioral score in CIRI rats through reduction of oxidative stress and anti-inflammation in the cerebral infarction region.]]> Mon 28 Nov 2022 17:29:30 AEDT ]]> Involvement of apoptosis in the protective effects of Dracocephalum moldavaica in cerebral ischemia reperfusion rat model https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:46650 Dracocephalum moldevica (DML) was found to exert protective effects on cerebral ischemia-reperfusion injury (CIRI); however, the mechanisms underlying the observed actions of this plant-derived mixture remain to be determined. Thus, the aim of this study was to examine the influence of DML on CIRI rat model induced by middle cerebral artery occlusion (MCAO). The following parameters were measured: (1) viable neurons in the infarcted area using Nissl staining; and (2) immunohistochemistry and Western blot were employed to determine protein expression levels of p53, bcl-2 associated X protein (bax) and B-cell lymphoma-2 (bcl-2), three biomarkers of apoptosis. MCAO significantly decreased the number of viable cortical pyramidal neurons in the infarcted area, while treatment with DML extract significantly elevated the number of viable neurons. MCAO was found to significantly elevate in gene expression levels of p53 and protein expression levels bax accompanied by diminished protein expression levels of bcl-2. Prior administration of DML extract produced marked reduction in gene expression levels of p53 and protein expression levels bax but increased in protein expression levels of bcl-2. Data suggested apoptosis was initiated in MCAO and that DML was effective in treating CIRI via an anti-apoptotic action as evidenced by inhibition of gene expression levels of p53 and protein expression levels of bax with concomitant elevation in protein expression levels of bcl-2. Our findings suggest that extract of DML may prove beneficial in treatment of cerebrovascular disorders.]]> Mon 28 Nov 2022 17:22:23 AEDT ]]> The effects of phenylethanoid glycosides, derived from Herba cistanche, on cognitive deficits and antioxidant activities in male SAMP8 mice https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34031 Herba cistanche, are known to exert protective effects on cognitive deficits in Alzheimer's disease (AD); however, the underlying mechanisms of this herbal extract on cognitive performance remain unclear. The aim of this study was thus to examine the protective mechanism attributed to PhG on cognitive deficits in an AD senescence accelerated mouse prone 8 (SAMP8) model. Cognitive deficit parameters examined included (1) Morris water maze (MWM) assessing cognitive performance and (2) quantification of dendritic spine density in hippocampal CA1 region by Golgi staining, a molecular biomarker of synaptic function. In addition, levels of malondialdehyde (MDA) and activities of superoxide dismutase (SOD) and gluthathione peroxidase (GSH-Px) were determined to examine the potential role of oxidant processes in cognitive dysfunction. Data showed that PhG significantly decreased escape latency and path length, associated with a rise in the percentage of time spent in the target quadrant and number of platform crossings. In addition, PhG significantly increased dendritic spine density in the hippocampal CA1 region accompanied by elevated expression levels of synaptophysin (SYN) and post synaptic density 95 (PSD-95), reduced MDA content, and elevated the activities of SOD and GSH-Px. Data suggest that the ability of PhG to ameliorate cognitive deficits in SAMP8 mice may be related to promotion in synaptic plasticity involving antioxidant processes.]]> Mon 04 Feb 2019 11:38:53 AEDT ]]>