New insights into mechanism for the effect of resveratrol preconditioning against cerebral ischemic stroke: Possible role of matrix metalloprotease-9

Therapeutic Effects of Intranasal Administration of Resveratrol on the Rat Model of Brain Ischemia

Background

Resveratrol is a natural phenolic compound widely found in plants. Previous studies have suggested its neuroprotective role in cerebral ischemia due to its anti-oxidative, anti-inflammatory, and anti-apoptotic effects. Intranasal administration of resveratrol enhances its capacity to penetrate the blood-brain barrier, increasing therapeutic efficacy and safety.

Objective

We aimed to examine the therapeutic potential of intranasal administration of resveratrol treatment in rats exposed to cerebral ischemia.

Methods

Sixty-four male rats were divided into three groups: the sham group, which was exposed to only surgical stress; the vehicle and resveratrol groups, which received intranasal vehicle or 50 mg/kg resveratrol for 7 days following middle cerebral artery occlusion, respectively. We assessed the modified neurologic severity scores, wire hanging tests, blood-brain barrier disruption, brain water content, and infarct volume. Levels of matrix metalloproteinase-9, nuclear factor-kappa B, B-cell lymphoma protein 2, and B-cell lymphoma protein 2-associated X messenger RNA expression were examined.

Results

At 3- and 7-days post-ischemia, rats receiving intranasal resveratrol had lower modified neurological severity scores and a smaller brain infarct volume than the rats receiving vehicle. Additionally, the intranasal resveratrol-treated rats showed significantly prolonged wire-hanging performance at the 7-day mark post-ischemia compared to the vehicle group. The blood-brain barrier disruption and brain water content were significantly lower in the resveratrol group than in the vehicle group. Furthermore, the resveratrol-treated group displayed lower expression of Matrix Metalloproteinase-9 and Nuclear Factor-Kappa B in contrast to the vehicle group, while the difference in expression levels of B-cell lymphoma protein 2-associated X and B-cell lymphoma protein 2 were not significant.

Conclusion

Intranasal administration of resveratrol showed neuroprotective effects on ischemic stroke by improving neurobehavioral function, reducing blood-brain barrier disruption, cerebral edema, and infarct volume. This treatment also downregulated Matrix Metalloproteinase-9 and Nuclear Factor-Kappa B expression, indicating its potential as a therapeutic option for ischemic stroke.

The role of miRNA-29b1 on the hypoxia-induced apoptosis in mammalian cardiomyocytes

Cardiomyocyte apoptosis is a complex biological process involving the interaction of many factors and signaling pathways. In hypoxic environment, cardiomyocytes may trigger apoptosis due to insufficient energy supply, increased production of oxygen free radicals, and disturbance of intracellular calcium ion balance. The present research aimed to investigate the role of microRNA-29b1 (miR-29b1) in hypoxia-treated cardiomyocytes and its potential mechanism involved. We established an in vitro ischemia model using AC16 and H9C2 cardiomyocytes through hypoxia treatment (1% O2, 48 h). Cell apoptosis was evaluated by flow cytometry using Annexin V FITC-PI staining assay. Moreover, we used Western blot and immunofluorescence analysis to determine the expression of Bcl-2, Bax caspase-3 and Cx43 proteins. We found that miR-29b1 protected AC16 and H9C2 cells from hypoxia-induced injury as evidence that miR-29b1 attenuated the effects of hypoxia treatment on AC16 and H9C2 cell apoptosis after hypoxia treatment. In conclusion, our findings suggest that miR-29b1 may have potential cardiovascular protective effects during ischemia-related myocardial injury.

Resveratrol: a potential medication for the prevention and treatment of varicella zoster virus-induced ischemic stroke

BACKGROUND

Infection rate of varicella zoster virus (VZV) is 95% in humans, and VZV infection is strongly associated with ischemic stroke (IS). However, the underlying molecular mechanisms of VZV-induced IS are still unclear, and there are no effective agents to treat and prevent VZV-induced IS.

OBJECTIVE

By integrating bioinformatics, this study explored the interactions between VZV and IS and potential medication to treat and prevent VZV-induced IS.

METHODS

In this study, the VZV and IS datasets from the GEO database were used to specify the common genes. Then, bioinformatics analysis including Gene Ontology, Kyoto Encyclopedia Genes Genomes and Protein-Protein Interaction network analysis was performed. Further, the hub genes, transcription factor (TF) gene interactions, TF-miRNA co-regulatory network and potential drug were obtained. Finally, validation was performed using molecular docking and molecular dynamics simulations.

RESULTS

The potential molecular mechanisms of VZV-induced IS were studied using multiple bioinformatics tools. Ten hub genes were COL1A2, DCN, PDGFRB, ACTA2, etc. TF genes and miRNAs included JUN, FOS, CREB, BRCA1, PPARG, STAT3, miR-29, etc. A series of mechanism may be involved, such as inflammation, oxidative stress, blood-brain barrier disruption, foam cell generation and among others. Finally, we proposed resveratrol as a potential therapeutic medicine for the prevention and treatment of VZV-induced IS. Molecular docking and molecular dynamics results showed that resveratrol and hub genes exhibited strong binding score.

CONCLUSIONS

Resveratrol could be an alternative for the prevention and treatment of VZV-IS. More in vivo and in vitro studies are needed in the future to fully explore the molecular mechanisms between VZV and IS and for medication development.

LRG1 promotes hypoxia-induced cardiomyocyte apoptosis and autophagy by regulating hypoxia-inducible factor-1α

Cardiomyocyte apoptosis and autophagy play important roles in acute myocardial infarction (AMI), but the effect of leucine-rich alpha-2-glycoprotein 1 (LRG1) on the apoptosis and autophagy of H9c2 has not yet been reported. It was found through differential gene analysis and LASSO analysis that LRG1 was the key gene in AMI. In this study, western blot was applied to detect the protein expression of Bax, Bcl2, LC3, p62, LRG1 and hypoxia-inducible factor-1α (HIF-1α); CCK-8 assay was employed to detect cell viability; Annexin V-FITC/PI staining was adopted to evaluate apoptosis, and immunofluorescence assay was applied to detect autophagy. Under hypoxia conditions in H9c2 cells, LRG1 protein levels were increased, the cell activity was decreased, and apoptosis and autophagy were promoted; the downregulated LRG1 significantly enhanced cell viability but inhibited apoptosis and autophagy. When knocking down HIF-1α in the overexpressed LRG1 cells, the effects of LRG1 were reversed under hypoxia condition. In conclusion, LRG1/HIF-1α promoted H9c2 cell apoptosis and autophagy in hypoxia, potentially providing new ideas for the determination and treatment of AMI.

Abbreviation: LRG1: Leucine-rich alpha-2-glycoprotein 1; LRR: leucine-rich repeat; HIF-1α: Hypoxia-inducible factor-1α; AMI: acute myocardial infarction

Therapeutic Applications of Resveratrol in Hepatic Encephalopathy through Its Regulation of the Microbiota, Brain Edema, and Inflammation

Hepatic encephalopathy is a common complication in patients with liver cirrhosis and portosystemic shunting. Patients with hepatic encephalopathy present a variety of clinical features, including neuropsychiatric manifestations, cognitive dysfunction, impaired gut barrier function, hyperammonemia, and chronic neuroinflammation. These pathogeneses have been linked to various factors, including ammonia-induced oxidative stress, neuronal cell death, alterations in the gut microbiome, astrocyte swelling, and blood-brain barrier disruptions. Many researchers have focused on identifying novel therapeutics and prebiotics in the hope of improving the treatment of these conditions. Resveratrol is a natural polyphenic compound and is known to exert several pharmacological effects, including antioxidant, anti-inflammatory, and neuroprotective activities. Recent studies suggest that resveratrol contributes to improving the neuropathogenic effects of liver failure. Here, we review the current evidence describing resveratrol's effects in neuropathogenesis and its impact on the gut-liver axis relating to hepatic encephalopathy. We highlight the hypothesis that resveratrol exerts diverse effects in hepatic encephalopathy and suggest that these effects are likely mediated by changes to the gut microbiota, brain edema, and neuroinflammation.

Systemic Oxidative Stress: A key Point in Neurodegeneration - A Review

Systemic oxidative stress (SOS) has an important role in the mechanisms activation of neuronal death, involved in the neurodegenerative disease (ND) etiology. Brain is susceptible to oxidative stress injuries due to its high energy and metabolic request, therefore minimal imbalances of the redox state, as occurs in mitochondrial dysfunction, favour tissue injury and neuroinflammatory mechanisms activation. ND affect around the world about a billion people, without distinction of sex, educational level and economic status. Public measures generation that prevent ND from the SOS are possible promising therapeutic targets that could reduce the ND incidence. We discuss here the effects and mechanisms of SOS derived neurodegeneration, as well as the neuroinflammation repercussions for some cerebral structures.

Neuroprotection and antioxidants

Ischemia as a serious neurodegenerative disorder causes together with reperfusion injury many changes in nervous tissue. Most of the neuronal damage is caused by complex of biochemical reactions and substantial processes, such as protein agregation, reactions of free radicals, insufficient blood supply, glutamate excitotoxicity, and oxidative stress. The result of these processes can be apoptotic or necrotic cell death and it can lead to an irreversible damage. Therefore, neuroprotection and prevention of the neurodegeneration are highly important topics to study. There are several approaches to prevent the ischemic damage. Use of many modern therapeutical methods and the incorporation of several substances into the diet of patients is possible to stimulate the endogenous protective mechanisms and improve the life quality.

Novel promising therapeutics against chronic neuroinflammation and neurodegeneration in Alzheimer's disease

Alzheimer's disease (AD) is a progressive neurodegenerative disorder, characterized by deposition of amyloid plaques and neurofibrillary tangles, as well as microglial and astroglial activation, and, finally, leading to neuronal dysfunction and death. Current treatments for AD primarily focus on enhancement of cholinergic transmission. However, these treatments are only symptomatic, and no disease-modifying drug is available for the treatment of AD patients. This review will provide an overview of the antioxidant, anti-inflammatory, anti-amyloidogenic, neuroprotective, and cognition-enhancing effects of a variety of nutraceuticals including curcumin, apigenin, docosahexaenoic acid, epigallocatechin gallate, α-lipoic acid and resveratrol and their potential for AD prevention and treatment. We suggest that therapeutic use of these compounds might lead to a safe strategy to delay the onset of AD or slow down its progression. The continuing investigation of the potential of these substances is necessary as they are promising compounds to yield a possible remedy for this pervasive disease.

Resveratrol attenuates the blood-brain barrier dysfunction by regulation of the MMP-9/TIMP-1 balance after cerebral ischemia reperfusion in rats

The collapse of the blood-brain barrier (BBB) is one of the fundamental pathophysiology changes during cerebral ischemia reperfusion injury. Resveratrol has been recently reported to reduce cerebral ischemic damage by regulating the matrix metalloproteinase-9 (MMP-9). But, more direct evidence for the explanation of the BBB protected by resveratrol against cerebral ischemia reperfusion is still lacking. Therefore, the present study was aimed to investigate the regulation of BBB integrity by resveratrol after cerebral ischemia reperfusion and to determine the role of the MMP-9 and its endogenous inhibitor TIMP-1 balance in this process. Cerebral ischemia was induced by middle cerebral artery occlusion in rats. The BBB function was evaluated by brain water content and the Evans blue dye extravasation; the activities of MMP-9 and TIMP-1 were detected by using gelatin zymography analysis, and cellular apoptosis was examined by TUNEL staining. We confirmed that resveratrol reduced the cerebral ischemia reperfusion damage, brain edema, and Evans blue dye extravasation. Moreover, we found that resveratrol improved the balance of MMP-9/TIMP-1 in terms of their expressions and activities. A TIMP-1 neutralizing antibody reversed those neuroprotective effects of resveratrol. In conclusion, resveratrol attenuated the cerebral ischemia by maintaining the integrity of BBB via regulation of MMP-9 and TIMP-1.

Systemic and renal oxidative stress in the pathogenesis of hypertension: modulation of long-term control of arterial blood pressure by resveratrol

Hypertension affects over 25% of the global population and is associated with grave and often fatal complications that affect many organ systems. Although great advancements have been made in the clinical assessment and treatment of hypertension, the cause of hypertension in over 90% of these patients is unknown, which hampers the development of targeted and more effective treatment. The etiology of hypertension involves multiple pathological processes and organ systems, however one unifying feature of all of these contributing factors is oxidative stress. Once the body's natural anti-oxidant defense mechanisms are overwhelmed, reactive oxygen species (ROS) begin to accumulate in the tissues. ROS play important roles in normal regulation of many physiological processes, however in excess they are detrimental and cause widespread cell and tissue damage as well as derangements in many physiological processes. Thus, control of oxidative stress has become an attractive target for pharmacotherapy to prevent and manage hypertension. Resveratrol (trans-3,5,4'-Trihydroxystilbene) is a naturally occurring polyphenol which has anti-oxidant effects in vivo. Many studies have shown anti-hypertensive effects of resveratrol in different pre-clinical models of hypertension, via a multitude of mechanisms that include its function as an anti-oxidant. However, results have been mixed and in some cases resveratrol has no effect on blood pressure. This may be due to the heavy emphasis on peripheral vasodilator effects of resveratrol and virtually no investigation of its potential renal effects. This is particularly troubling in the arena of hypertension, where it is well known and accepted that the kidney plays an essential role in the long term regulation of arterial pressure and a vital role in the initiation, development and maintenance of chronic hypertension. It is thus the focus of this review to discuss the potential of resveratrol as an anti-hypertensive treatment via amelioration of oxidative stress within the framework of the fundamental physiological principles of long term regulation of arterial blood pressure.