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Cerebral ischemia-reperfusion injury (CIRI) occurs frequently clinically as a complication following cardiovascular resuscitation resulting in neuronal damage specifically to the hippocampal CA1 region with consequent cognitive impairment. Apoptosis and oxidative stress were proposed as major risk factors associated with CIRI development. Previously, glycosides obtained from Cistanche deserticola (CGs) were shown to play a key role in counteracting CIRI; however, the underlying mechanisms remain to be determined. This study aimed to investigate the neuroprotective effect of CGs on subsequent CIRI in rats. The model of CIRI was established for 2 hr and reperfusion for 24 hr by middle cerebral artery occlusion (MCAO) model. The MCAO rats were used to measure the antioxidant and anti-apoptotic effects of CGs on CIRI. Neurological function was evaluated by the Longa neurological function score test. 2,3,5-Triphenyltetrazolium chloride (TTC) staining was used to detect the area of cerebral infarction. Nissl staining was employed to observe neuronal morphology. TUNEL staining was used to detect neuronal apoptosis, while Western blot determined protein expression levels of factors for apoptosis-related and PI3K/AKT/Nrf2 signaling pathway. Data demonstrated that CGs treatment improved behavioral performance, brain injury, and enhanced antioxidant and anti-apoptosis in CIRI rats. In addition, CGs induced activation of PI3K/AKT/Nrf2 signaling pathway accompanied by inhibition of the expression of apoptosis-related factors. Evidence indicates that CGs amelioration of CIRI involves activation of the PI3K/AKT/Nrf2 signaling pathway associated with increased cellular viability suggesting these glycosides may be considered as an alternative compound for CIRI treatment. [ABSTRACT FROM AUTHOR]

One of the main pathological features noted in Alzheimer's disease (AD) is the presence of plagues of aggregated β-amyloid (Aβ1–42)-peptides. Excess deposition of amyloid-β oligomers (AβO) are known to promote neuroinflammation. Sequentially, following neuroinflammation astrocytes become activated with cellular characteristics to initiate activated astrocytes. The purpose of this study was to determine whether total flavonoids derived from Dracocephalum moldavica L. (TFDM) inhibited Aβ1–42-induced damage attributed to activated C8-D1A astrocytes. Western blotting and ELISA were used to determine the expression of glial fibrillary acidic protein (GFAP), and complement C3 to establish the activation status of astrocytes following induction from exposure to Aβ1–42. Data demonstrated that stimulation of C8-D1A astrocytes by treatment with 40 μM Aβ1–42 for 24 hr produced significant elevation in protein expression and protein levels of acidic protein (GFAP) and complement C3 accompanied by increased expression and levels of inflammatory cytokines. Treatment with TFDM or the clinically employed drug donepezil in AD therapy reduced production of inflammatory cytokines, and toxicity initiated following activation of C8-D1A astrocytes following exposure to Aβ1–42. Therefore, TFDM similar to donepezil inhibited inflammatory secretion in reactive astrocytes, suggesting that TFDM may be considered as a potential compound to be utilized in AD therapy. [ABSTRACT FROM AUTHOR]

Schisandrin B, an active substance, is derived from Chinese herb fruit Wuweizi, which exerts various pharmacological activities and has displayed significant beneficial effects in ameliorating Alzheimer’s disease (AD). The aim of this study was to further extend our examination for the use of schisandrin B extract in the potential treatment of AD effects by investigating DNA methylation (DNMT), known to be modified in this disease using SH-SY5Y neuronal cell line exposed to β-amyloid protein (Aβ1-42). In particular, the purpose of this investigation was to examine alterations in mRNA and protein expression of DNMT. Data demonstrated that schisandrin B blocked Aβ1-42-mediated injury in SH-SY5Y neuronal cell line as evidenced by a restoration of cellular morphology and cell viability to approximate control levels at the highest 10 μg/ml Schisandrin B. Incubation with Aβ1-42significantly decreased mRNA and protein expression of DNMT3A and DNMT1 in SH-SY5Y neuronal cell line. Incubation with Aβ1-42followed by 24 treatment with schisandrin B significantly inhibited the Aβ1-42-induced changes in mRNA and protein expression of DNMT3A and DNMT3B in a concentration-dependent manner. It is of interest that the mRNA expression of DNMT3A and DNMT1 were significantly higher than control. Data thus indicate schisandrin B was effective in inhibiting the actions of Aβ1-42on cell survival and morphology and that DNA methylation may be associated with the beneficial findings. [ABSTRACT FROM PUBLISHER]

The field detection results of high-density electrical method showed that the rock mass occurrence state, structure characteristics and mechanical properties in east open-pit slope take changes on the influence of Laohutai underground mining, which had a major influence on slope stability. The distribution of disturbance area and spatial position relation between the slope and disturbance area was stood by application of "three zones" theory. The rock mass structure characteristics and main failure mode in different parts of the slope was pointed out as following: Rock mass integrity in the caving zone is bad and broken seriously, so it is easy to take local collapse and block topple instability; Abscission layer and vertical joints develops well in the rock mass of fracture zone, so it mainly takes crooked-toppling instability; Rock mass integrity in bending zone is well, which still keeps the stratified structural, and is likely to take local crooked-toppling instability; Rock mass in tension area is under powerful tensioning action, so it mainly takes pulling damage. [ABSTRACT FROM AUTHOR]

Renal fibrosis (RF) is a chronic and fatal disease related to the gradual deterioration of kidney function. MicroRNAs (miRNAs) play a key role in cellular functions and several of them related to the pathogenesis of RF have been identified, although the underlying mechanisms are unclear. In order to explore the miRNAs involved in RF progression, we established a model in rats by the unilateral ureteral ligation method. The animals were randomly divided into the control group, and the 2 week, 4 week and 6 week model groups. The indices of renal function were measured using routine biochemical assays. The differentially expressed miRNAs (DE-miRNAs) between the sham-operated and modelled rats were screened, and their putative target genes were identified using the miRanda software and functionally annotated by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. The expression of transforming growth factor β1 (TGF-β1), Smad3 and Smad7 was confirmed by RT-PCR. Compared to the sham-operated group, the model groups showed a decrease in SOD activity, along with the increased renal coefficient, and higher MDA, HYP, Scr, BUN and ALB levels. In addition, TGF-β1, Smad3 and Smad7 were also upregulated in the RF groups. We identified 274 known and 11 novel DE-miRNAs in the 2 week, 114 known and 6 novel DE-miRNAs in the 4 week, and 41 known and 1 novel DE-miRNAs in the 6 week model groups. The putative target genes of these DE-miRNAs were enriched in metabolic processes, apoptosis, pyrimidine metabolism, and TNF and VEGF signalling pathways. Based on our findings, we surmise that miR-146a-3p, miR-148a-3p, miR-130a-5p, miR-362-3p and miR-122-5p are likely to be involved in the occurrence and development of RF, and miR-122-5p may play an inhibitory role. The underlying mechanisms need further investigation.

Cognitive dysfunction in Alzheimer's disease is strongly associated with a reduction in synaptic plasticity, which may be induced by oxidative stress. Testosterone is beneficial in learning and memory, although the underlying protective mechanism of testosterone on cognitive performance remains unclear. This study explored the protective mechanism of a subcutaneous injection of 0.75 mg testosterone on cognitive dysfunction induced by bilateral injections of amyloid beta 1-42 oligomers into the lateral ventricles of male rats. Morris water maze test results demonstrated that testosterone treatment remarkably reduced escape latency and path length in Alzheimer's disease rat models. During probe trials, testosterone administration significantly elevated the percentage of time spent in the target quadrant and the number of platform crossings. However, flutamide, an androgen receptor antagonist, inhibited the protective effect of testosterone on cognitive performance in Alzheimer's disease rat models. Nissl staining, immunohistochemistry, western blot assay, and enzyme-linked immunosorbent assay results showed that the number of intact hippocampal pyramidal cells, the dendritic spine density in the hippocampal CA1 region, the immune response and expression level of postsynaptic density protein 95 in the hippocampus, and the activities of superoxide dismutase and glutathione peroxidase were increased with testosterone treatment. In contrast, testosterone treatment reduced malondialdehyde levels. Flutamide inhibited the effects of testosterone on all of these indicators. Our data showed that the protective effect of testosterone on cognitive dysfunction in Alzheimer's disease is mediated via androgen receptors to scavenge free radicals, thereby enhancing synaptic plasticity., Competing Interests: None