The Effects of Mouse Recombinant Resistin on mRNA Expression of Proinflammatory and Anti-Inflammatory Cytokines and Heat Shock Protein-70 in Experimental Stroke Model

ACTH-like Peptides Compensate Rat Brain Gene Expression Profile Disrupted by Ischemia a Day After Experimental Stroke

Background: Ischemic stroke results from a disruption of cerebral blood flow. Adrenocorticotropic hormone (ACTH) serves as the basis for the creation of synthetic peptides as neuroprotective agents for stroke therapy. Previously, using RNA-Seq we first revealed differential expressed genes (DEGs) associated with ACTH(4-7)PGP (Semax) and ACTH(6-9)PGP peptides under cerebral ischemia conditions. Analysis was carried out at 4.5 h after transient middle cerebral artery occlusion (tMCAO) model in the ipsilateral frontal cortex of a rat brain. Methods: Here, we analyzed the penumbra-associated frontal cortex of rats and actions under the same peptides at 24 h after tMCAO using RNA-Seq. Results: 3774 DEGs (fold change > 1.5 and Padj < 0.05) were identified under ischemia conditions, whereas 1539 and 2066 DEGs were revealed under Semax and ACTH(6-9)PGP peptides at 24 h after tMCAO. Furthermore, both peptides significantly reduced expression distortions caused by ischemia for 1171 genes associated with immune and neurosignaling pathways. Concomitantly, there were 32 DEGs under ACTH(6-9)PGP versus Semax administration at 24 h after tMCAO. Besides, neurogenesis-, angiogenesis-, protein kinase- and growth factor-related DEGs were revealed under peptides action. Previously, we observed the neuroprotective effect of peptides at the histological level in rat brains at 24 h after tMCAO. Thus, here we demonstrate the transcriptome manifestation of this histological effect. Furthermore, comparison with previous data at the 4.5 h post-tMCAO time point showed that the pattern of peptide action on the transcriptome depends on the time elapsed after tMCAO. Conclusions: We revealed that the effect of ACTH(6-9)PGP was more similar to Semax than different from it a day after tMCAO. At this time point, ACTH-like peptides compensated rat brain gene expression profiles disrupted by ischemia. Thus, our results may be useful for selecting more effective structures for future anti-stroke drugs and appropriate post-stroke time points for their testing.

Are Ischemic Stroke and Alzheimer's Disease Genetically Consecutive Pathologies?

Complex diseases that affect the functioning of the central nervous system pose a major problem for modern society. Among these, ischemic stroke (IS) holds a special place as one of the most common causes of disability and mortality worldwide. Furthermore, Alzheimer's disease (AD) ranks first among neurodegenerative diseases, drastically reducing brain activity and overall life quality and duration. Recent studies have shown that AD and IS share several common risk and pathogenic factors, such as an overlapping genomic architecture and molecular signature. In this review, we will summarize the genomics and RNA biology studies of IS and AD, discussing the interconnected nature of these pathologies. Additionally, we highlight specific genomic points and RNA molecules that can serve as potential tools in predicting the risks of diseases and developing effective therapies in the future.

Synthetic Adrenocorticotropic Peptides Modulate the Expression Pattern of Immune Genes in Rat Brain following the Early Post-Stroke Period

Ischemic stroke is an acute local decrease in cerebral blood flow due to a thrombus or embolus. Of particular importance is the study of the genetic systems that determine the mechanisms underlying the formation and maintenance of a therapeutic window (a time interval of up to 6 h after a stroke) when effective treatment can be provided. Here, we used a transient middle cerebral artery occlusion (tMCAO) model in rats to study two synthetic derivatives of adrenocorticotropic hormone (ACTH). The first was ACTH(4-7)PGP, which is known as Semax. It is actively used as a neuroprotective drug. The second was the ACTH(6-9)PGP peptide, which is elucidated as a prospective agent only. Using RNA-Seq analysis, we revealed hundreds of ischemia-related differentially expressed genes (DEGs), as well as 131 and 322 DEGs related to the first and second peptide at 4.5 h after tMCAO, respectively, in dorsolateral areas of the frontal cortex of rats. Furthermore, we showed that both Semax and ACTH(6-9)PGP can partially prevent changes in the immune- and neurosignaling-related gene expression profiles disturbed by the action of ischemia at 4.5 h after tMCAO. However, their different actions with regard to predominantly immune-related genes were also revealed. This study gives insight into how the transcriptome depends on the variation in the structure of the related peptides, and it is valuable from the standpoint of the development of measures for early post-stroke therapy.

Inflammatory biomarkers of ischemic stroke

Ischemic stroke remains the second leading cause of death and among the major causes of morbidity worldwide. Therapeutic options are currently limited to early reperfusion strategies, while pharmacological neuroprotective strategies despite showing promising results in the experimental setting constantly failed to enter the clinical arena. Inflammation plays an important role in the pathophysiology of ischemic stroke and mediators of inflammation have been longtime investigated as possible prognostic marker and therapeutic target for stroke patients. Here, we summarized available evidence on the role of cytokines, soluble adhesion molecules and adipokines in the pathophysiology, prognosis and therapy of ischemic stroke.

Activation of PPAR-β/δ Attenuates Brain Injury by Suppressing Inflammation and Apoptosis in a Collagenase-Induced Intracerebral Hemorrhage Mouse Model

Brain injury has been proposed as the major cause of the poor outcomes associated with intracerebral hemorrhage (ICH). Emerging evidence indicates that the nuclear receptor, peroxisome proliferator-activated receptor β/δ (PPAR-β/δ), plays a crucial role in the pathological process of central nervous impairment. The present study was undertaken to evaluate the protective effects of PPAR-β/δ activation using a selective PPAR-β/δ agonist, GW0742, against brain injury after ICH in a mouse model. ICH was induced by intravenous injection of collagenase into the right caudate putamen. To examine the protective effect of PPAR-β/δ activation against ICH-induced brain injury, mice were either intraperitoneally injected with GW0742 (3 mg/kg, body weight) or saline (control group) 30 min before inducing ICH. Behavioral dysfunction was evaluated 24 and 72 h after injury. Then, all mice were killed to assess hematoma volume, brain water content, and blood-brain barrier (BBB) permeability. TUNEL and Nissl staining were performed to quantify the brain injury. The expression of PPAR-β/δ, interleukin (IL)-1β, tumor necrosis factor (TNF)-α, Bcl-2-related X-protein (Bax), and B-cell lymphoma 2 (Bcl-2) in the perihematomal area was examined by immunohistochemistry and western blotting analysis. Mice treated with GW0742 showed significantly less severe behavioral deficits compared to the control group, accompanied by increased expression of PPAR-β/δ and Bcl-2, and increased expression of IL-1β, TNF-α, and Bax decreased simultaneously in the GW0742-treated group. Furthermore, the GW0742-pretreated group showed significantly less brain edema and BBB leakage. Neuronal loss was attenuated, and the number of apoptotic neuronal cells in perihematomal tissues reduced, in the GW0742-pretreated group compared to the control group. However, the hematoma volume did not decrease significantly on day 3 after ICH. These results suggest that the activation of PPAR-β/δ exerts a neuroprotective effect on ICH-induced brain injury, possibly through anti-inflammatory and anti-apoptotic pathways.