Protection by tetrahydroxystilbene glucoside against cerebral ischemia: involvement of JNK, SIRT1, and NF-kappaB pathways and inhibition of intracellular ROS/RNS generation

THSG alleviates cerebral ischemia/reperfusion injury via the GluN2B-CaMKII-ERK1/2 pathway

BACKGROUND

The potential therapeutic targeting of PINK1-PARK2-mediated mitophagy against cerebral ischemia/reperfusion (CI/R) injury involves the pathophysiological processes of neurovascular unit (NVU) and is closely associated with N-methyl-D-aspartate receptors (NMDARs) commonly expressed in NVU. 2,3,5,4'-Tetrahydroxy-stilbene-2-O-β-D-glucoside (THSG), a compound derived from the traditional Chinese medicine Polygonum multiflorum Thunb., has demonstrated notable neuroprotective properties against CI/R injury. However, it remains unclear whether THSG exerts its protective effects through GluN2B related PINK1/ PARK2 pathway.

PURPOSE

This study aims to explore the pharmacological effects of THSG on alleviating CI/R injury via the GluN2B-CaMKII-ERK1/2 pathway.

METHODS

THSG neuroprotection against CI/R injury was studied in transient middle cerebral artery occlusion/reversion (tMCAO/R) model rats and in oxygen and glucose deprivation/ reoxygenation (OGD/R) induced neurons. PINK1-PARK2-mediated mitophagy involvement in the protective effect of THSG was investigated in tMCAO/R rats and OGD/R-induced neurons via THSG and 3-methyladenine (3-MA) treatment. Furthermore, the beneficial role of GluN2B in reperfusion and its contribution to the THSG effect via CaMKII-ERK1/2 and PINK1-PARK2-mediated mitophagy was explored using the GluN2B-selective antagonist Ro 25-6981 both in vivo and in vitro. Finally, the interaction between THSG and GluN2B was evaluated using molecular docking.

RESULTS

THSG significantly reduced infarct volume, neurological deficits, penumbral neuron structure, and functional damage, upregulated the inhibitory apoptotic marker Bcl-2, and suppressed the increase of pro-apoptotic proteins including cleaved caspase-3 and Bax in tMCAO/R rats. THSG (1 μM) markedly improved the neuronal survival under OGD/R conditions. Furthermore, THSG promoted PINK1 and PARK2 expression and increased mitophagosome numbers and LC3-II-LC3-I ratio both in vivo and in vitro. The effects of THSG were considerably abrogated by the mitophagy inhibitor 3-MA in OGD/R-induced neurons. Inhibiting GluN2B profoundly decreased mitophagosome numbers and OGD/R-induced neuronal viability. Specifically, inhibiting GluN2B abolished the protection of THSG against CI/R injury and reversed the upregulation of PINK1-PARK2-mediated mitophagy by THSG. Inhibiting GluN2B eliminated THSG upregulation of ERK1/2 and CaMKII phosphorylation. The molecular docking analysis results demonstrated that THSG bound to GluN2B (binding energy: -5.2 ± 0.11 kcal/mol).

CONCLUSIONS

This study validates the premise that THSG alleviates CI/R injury by promoting GluN2B expression, activating CaMKII and ERK1/2, and subsequently enhancing PINK1-PARK2-mediated mitophagy. This work enlightens the potential of THSG as a promising candidate for novel therapeutic strategies for treating ischemic stroke.

Preclinical Evidence and Underlying Mechanisms of Polygonum multiflorum and Its Chemical Constituents Against Cognitive Impairments and Alzheimer's Disease

Objectives

Cognitive impairments, ranging from mild to severe, adversely affect daily functioning, quality of life, and work capacity. Despite significant efforts in the past decade, more than 200 promising drug candidates have failed in clinical trials. Herbal remedies are gaining interest as potential treatments for dementia due to their long history and safety, making them valuable for drug development. This review aimed to examine the mechanisms behind the effect of Polygonum multiflorum on cognitive function.

Methods

This study focused primarily on the effects of Polygonum multiflorum and its chemical constituents on cognitive behavioral outcomes including the Morris water maze, the passive avoidance test, and the Y maze, as well as pathogenic targets of cognitive impairment and Alzheimer's disease (AD) like amyloid deposition, amyloid precursor protein, tau hyperphosphorylation, and cognitive decline. Additionally, a thorough evaluation of the mechanisms behind Polygonum multiflorum's impact on cognitive function was conducted. We reviewed the most recent data from preclinical research done on experimental models, particularly looking at Polygonum multiflorum's effects on cognitive decline and AD.

Results

According to recent research, Poligonum multiflorum and its bioactive components, stilbene, and emodin, influence cognitive behavioral results and regulate the pathological target of cognitive impairment and AD. Their mechanisms of action include reducing oxidative and mitochondrial damage, regulating neuroinflammation, halting apoptosis, and promoting increased neurogenesis and synaptogenesis.

Conclusion

This review serves as a comprehensive compilation of current experiments on AD and other cognitive impairment models related to the therapeutic effects of Polygonum multiflorum. We believe that these findings can serve as a basis for future clinical trials and have potential applications in the treatment of human neurological disorders.

Luteolin-7-O-β-d-glucuronide Ameliorates Cerebral Ischemic Injury: Involvement of RIP3/MLKL Signaling Pathway

Luteolin-7-O-β-d-glucuronide (LGU) is a major active flavonoid glycoside compound that is extracted from Ixeris sonchifolia (Bge.) Hance, and it is a Chinese medicinal herb mainly used for the treatment of coronary heart disease, angina pectoris, cerebral infarction, etc. In the present study, the neuroprotective effect of LGU was investigated in an oxygen glucose deprivation (OGD) model and a middle cerebral artery occlusion (MCAO) rat model. In vitro, LGU was found to effectively improve the OGD-induced decrease in neuronal viability and increase in neuronal death by a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and a lactate dehydrogenase (LDH) leakage rate assay, respectively. LGU was also found to inhibit OGD-induced intracellular Ca2+ overload, adenosine triphosphate (ATP) depletion, and mitochondrial membrane potential (MMP) decrease. By Western blotting analysis, LGU significantly inhibited the OGD-induced increase in expressions of receptor-interacting serine/threonine-protein kinase 3 (RIP3) and mixed lineage kinase domain-like protein (MLKL). Moreover, molecular docking analysis showed that LGU might bind to RIP3 more stably and firmly than the RIP3 inhibitor GSK872. Immunofluorescence combined with confocal laser analyses disclosed that LGU inhibited the aggregation of MLKL to the nucleus. Our results suggest that LGU ameliorates OGD-induced rat primary cortical neuronal injury via the regulation of the RIP3/MLKL signaling pathway in vitro. In vivo, LGU was proven, for the first time, to protect the cerebral ischemia in a rat middle cerebral artery occlusion (MCAO) model, as shown by improved neurological deficit scores, infarction volume rate, and brain water content rate. The present study provides new insights into the therapeutic potential of LGU in cerebral ischemia.

Nrf2: a dark horse in doxorubicin-induced cardiotoxicity

Being a broad-spectrum anticancer drug, doxorubicin is indispensable for clinical treatment. Unexpectedly, its cardiotoxic side effects have proven to be a formidable obstacle. Numerous studies are currently devoted to elucidating the pathological mechanisms underlying doxorubicin-induced cardiotoxicity. Nrf2 has always played a crucial role in oxidative stress, but numerous studies have demonstrated that it also plays a vital part in pathological mechanisms like cell death and inflammation. Numerous studies on the pathological mechanisms associated with doxorubicin-induced cardiotoxicity demonstrate this. Several clinical drugs, natural and synthetic compounds, as well as small molecule RNAs have been demonstrated to prevent doxorubicin-induced cardiotoxicity by activating Nrf2. Consequently, this study emphasizes the introduction of Nrf2, discusses the role of Nrf2 in doxorubicin-induced cardiotoxicity, and concludes with a summary of the therapeutic modalities targeting Nrf2 to ameliorate doxorubicin-induced cardiotoxicity, highlighting the potential value of Nrf2 in doxorubicin-induced cardiotoxicity.

Neuroprotective Effects of Tryptanthrin-6-Oxime in a Rat Model of Transient Focal Cerebral Ischemia

The activation of c-Jun N-terminal kinase (JNK) plays an important role in stroke outcomes. Tryptanthrin-6-oxime (TRYP-Ox) is reported to have high affinity for JNK and anti-inflammatory activity and may be of interest as a promising neuroprotective agent. The aim of this study was to investigate the neuroprotective effects of TRYP-Ox in a rat model of transient focal cerebral ischemia (FCI), which involved intraluminal occlusion of the left middle cerebral artery (MCA) for 1 h. Animals in the experimental group were administered intraperitoneal injections of TRYP-Ox 30 min before reperfusion and 23 and 47 h after FCI. Neurological status was assessed 4, 24, and 48 h following FCI onset. Treatment with 5 and 10 mg/kg of TRYP-Ox decreased mean scores of neurological deficits by 35-49 and 46-67% at 24 and 48 h, respectively. At these doses, TRYP-Ox decreased the infarction size by 28-31% at 48 h after FCI. TRYP-Ox (10 mg/kg) reduced the content of interleukin (IL) 1β and tumor necrosis factor (TNF) in the ischemic core area of the MCA region by 33% and 38%, respectively, and attenuated cerebral edema by 11% in the left hemisphere, which was affected by infarction, and by 6% in the right, contralateral hemisphere 24 h after FCI. TRYP-Ox reduced c-Jun phosphorylation in the MCA pool at 1 h after reperfusion. TRYP-Ox was predicted to have high blood-brain barrier permeability using various calculated descriptors and binary classification trees. Indeed, reactive oxidant production was significantly lower in the brain homogenates from rats treated with TRYP-Ox versus that in control animals. Our data suggest that the neuroprotective activity of TRYP-Ox may be due to the ability of this compound to inhibit JNK and exhibit anti-inflammatory and antioxidant activity. Thus, TRYP-Ox may be considered a promising neuroprotective agent that potentially could be used for the development of new treatment strategies in cerebral ischemia.

Neuroprotection of NAD+ and NBP against ischemia/reperfusion brain injury is associated with restoration of sirtuin-regulated metabolic homeostasis

Background: Ischemic stroke seriously threatens human health because of high rates of morbidity, mortality and disability. This study compared the effects of nicotinamide adenine dinucleotide (NAD+) and butylphthalide (NBP) on in vitro and in vivo ischemic stroke models.

Methods: Transient middle cerebral artery occlusion/reperfusion (t-MCAO/R) model was established in mice, and the cultured primary cortical neurons were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R). Cerebral infarct volume, neurobehavioral indices, antioxidant activity, ATP level and lactic acid content were determined. The neuroprotective effects of NAD+ or NBP were compared using sirtuin inhibitor niacinamide (NAM).

Results: Intraperitoneal injection of NBP within 4 h or intravenous injection of NAD+ within 1 h after t-MCAO/R significantly reduced the volume of infarcts, cerebral edema, and neurological deficits. Administration of NAD+ and NBP immediately after t-MCAO/R in mice showed similar neuroprotection against acute and long-term ischemic injury. Both NAD+ and NBP significantly inhibited the accumulation of MDA and H2O2 and reduced oxidative stress. NAD+ was superior to NBP in inhibiting lipid oxidation and DNA damage. Furthermore, although both NAD+ and NBP improved the morphology of mitochondrial damage induced by ischemia/reperfusion, NAD+ more effectively reversed the decrease of ATP and increase of lactic acid after ischemia/reperfusion compared with NBP. NAD+ but not NBP treatment significantly upregulated SIRT3 in the brain, but the sirtuin inhibitor NAM could abolish the protective effect of NAD+ and NBP by inhibiting SIRT1 or SIRT3.

Conclusions: These results confirmed the protective effects of NAD+ and NBP on cerebral ischemic injury. NBP and NAD+ showed similar antioxidant effects, while NAD+ had better ability in restoring energy metabolism, possibly through upregulating the activity of SIRT1 and SIRT3. The protection provided by NBP against cerebral ischemia/reperfusion may be achieved through SIRT1.

Pharmacokinetic characteristics of emodin in polygoni Multiflori Radix Praeparata

ETHNOPHARMACOLOGICAL RELEVANCE

Polygoni Multiflori Radix Praeparata (Zhiheshouwu) has been a Wudang Taoist medicine for tonifying the liver and kidney, resolving turbidity and reducing lipid. Emodin is one of the active anthraquinones in Zhiheshouwu. Our previous studies showed that emodin (EM) and the other anthraquinones in Zhiheshouwu extract (HSWE) exerted similar inhibitory effects on liver cancer cells in vitro. However, it is still unknown if the other anthraquinones enhance pharmacokinetics (PK) of EM in HSWE in vivo.

AIM OF THE STUDY

In this study, we compared the PK characteristics of EM alone with that in Zhiheshouwu aiming to explore which anthraquinones in HSWE contribute to the changed PK of EM in rats.

MATERIALS AND METHODS

Quality control of HSWE was determined using high performance liquid chromatography (HPLC). The ratios of emodin to other anthraquinones, physcion (PH), chrysophanol (CH), rhein (RH), aloe-emodin (AE), emodin-8-O-β-D-glycoside (EMG), physcion-1-O-β-D-glycoside (PHG) and chrysophanol-8-O-β-D-glycoside (CHG) in HSWE were determined and analyzed using UPLC combined with tandem mass spectrometry (UPLC/MS). The PK parameters and intestinal tissue concentration of EM alone, EM in HSWE, or with other anthraquinones in SD rats were analyzed using UPLC/MS.

RESULTS

The quality of the Zhiheshouwu samples met the quality standard of the Chinese Pharmacopoeia (Version 2020). The PK results showed that compared with EM alone, C_max (239.90 ± 146.71 vs. 898.46 ± 291.62, P < 0.001), T_max (0.26 ± 0.15 vs. 12.55 ± 1.33, P < 0.001), AUC_0-t (1575.09 ± 570.46 vs. 12154.96 ± 5394.25, P < 0.001), and AUC_0-∞ (4742.51 ± 1837.62 vs. 37131.34 ± 21647.39, P < 0.001) of EM in HSWE were decreased due to PH and EMG, while the values of V_d (380.75 ± 217.74 vs. 11.75 ± 7.35, P < 0.001), T_1/2 (10.81 ± 1.99 vs. 6.65 ± 2.76, P < 0.05) and CL (19.30 ± 7.82 vs. 2.78 ± 1.88, P < 0.001) of EM in HSWE were increased due to PH and AE. In addition, the intestinal tissue concentration of emodin in HSWE was decreased compared with that of EM alone in 20 and 780 min (25.37 ± 5.98 vs. 43.29 ± 4.16 and 26.72 ± 4.03 vs. 43.40 ± 14.19, respectively. P < 0.05) dominantly due to RH and PH.

CONCLUSION

In conclusion, compared with treatment of EM alone, the AUC_0-t value of EM in HSWE was decreased with different ways in rats. PH shortened T_max, and increased V_d and CL. While AE prolonged T_1/2 of EM. This indicated that the other anthraquinones in HSWE changed the PK of EM in rats and participated in the complex effects of EM on liver cancer. Besides the other anthraquinones, other components (e.g., 2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside) in Zhiheshouwu may contribute in the pharmacokinetic and pharmacodynamic interactions with EM for anti-liver cancer.

Neuroprotective Strategies for Stroke by Natural Products: Advances and Perspectives

Cerebral ischemic stroke is a disease with high prevalence and incidence. Its management focuses on rapid reperfusion with intravenous thrombolysis and endovascular thrombectomy. Both therapeutic strategies reduce disability, but the therapy time window is short, and the risk of bleeding is high. Natural products (NPs) have played a key role in drug discovery, especially for cancer and infectious diseases. However, they have made little progress in clinical translation and pose challenges to the treatment of stroke. Recently, with the investigation of precise mechanisms in cerebral ischemic stroke and the technological development of NP-based drug discovery, NPs are addressing these challenges and opening up new opportunities in cerebral stroke. Thus, in this review, we first summarize the structure and function of diverse NPs, including flavonoids, phenols, terpenes, lactones, quinones, alkaloids, and glycosides. Then we propose the comprehensive neuroprotective mechanism of NPs in cerebral ischemic stroke, which involves complex cascade processes of oxidative stress, mitochondrial damage, apoptosis or ferroptosis-related cell death, inflammatory response, and disruption of the blood-brain barrier (BBB). Overall, we stress the neuroprotective effect of NPs and their mechanism on cerebral ischemic stroke for a better understanding of the advances and perspective in NPs application that may provide a rationale for the development of innovative therapeutic regimens in ischemic stroke.

Screening and identification of anti-acetylcholinesterase ingredients from Tianzhi granule based on ultrafiltration combined with ultra-performance liquid chromatography-mass spectrometry and in silico analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Tianzhi granule (TZG) is a traditional Chinese formula that is widely used for the treatment of vascular dementia (VaD).

AIM OF THE STUDY

To discover the herbs in TZG possessing acetylcholinesterase (AChE) inhibitory activity and to screen the anti-acetylcholinesterase ingredients from active herbs.

MATERIALS AND METHODS

In vitro AChE inhibitory activity assay of eleven herbal extracts was conducted. An ultrafiltration combined with ultra-performance liquid chromatography-mass spectrometry method was established to screen and identify the anti-acetylcholinesterase ingredients from active extracts. In addition, in vitro AChE inhibitory activity assay and molecular docking were adopted for further investigation. Moreover, ultra-performance liquid chromatography-mass spectrometry was performed for the content determination of active compounds in TZG.

RESULTS

Three herbs in TZG showed significant AChE inhibitory activity. A total of thirteen active ingredients were screened out and identified, and all of these compounds were present in TZG. Five available commercial standards presented moderate AChE inhibitory activity, and all of which have a relatively high content in TZG.

CONCLUSION

A number of herbs and compounds with acetylcholinesterase inhibitory activity were found in TZG, which provided a scientific basis for the material basis and quality control research of TZG.

Role of NAD+ and FAD in Ischemic Stroke Pathophysiology: An Epigenetic Nexus and Expanding Therapeutic Repertoire

The redox coenzymes viz., oxidized β-nicotinamide adenine dinucleotide (NAD⁺) and flavin adenine dinucleotide (FAD) by way of generation of optimal reducing power and cellular energy currency (ATP), control a staggering array of metabolic reactions. The prominent cellular contenders for NAD⁺ utilization, inter alia, are sirtuins (SIRTs) and poly(ADP-ribose) polymerase (PARP-1), which have been significantly implicated in ischemic stroke (IS) pathogenesis. NAD⁺ and FAD are also two crucial epigenetic enzyme-required metabolites mediating histone deacetylation and poly(ADP-ribosyl)ation through SIRTs and PARP-1 respectively, and demethylation through FAD-mediated lysine specific demethylase activity. These enzymes and post-translational modifications impinge on the components of neurovascular unit, primarily neurons, and elicit diverse functional upshots in an ischemic brain. These could be circumstantially linked with attendant cognitive deficits and behavioral outcomes in post-stroke epoch. Parsing out the contribution of NAD⁺/FAD-synthesizing and utilizing enzymes towards epigenetic remodeling in IS setting, together with their cognitive and behavioral associations, combined with possible therapeutic implications will form the crux of this review.

Role of Sirtuins in Physiology and Diseases of the Central Nervous System

Silent information regulators, sirtuins (SIRTs), are a family of enzymes which take part in major posttranslational modifications of proteins and contribute to multiple cellular processes, including metabolic and energetic transformations, as well as regulation of the cell cycle. Recently, SIRTs have gained increased attention as the object of research because of their multidirectional activity and possible role in the complex pathomechanisms underlying human diseases. The aim of this study was to review a current literature evidence of SIRTs' role in the physiology and pathology of the central nervous system (CNS). SIRTs have been demonstrated to be crucial players in the crosstalk between neuroinflammation, neurodegeneration, and metabolic alterations. The elucidation of SIRTs' role in the background of various CNS diseases offers a chance to define relevant markers of their progression and promising candidates for novel therapeutic targets. Possible diagnostic and therapeutic implications from SIRTs-related investigations are discussed, as well as their future directions and associated challenges.

A comprehensive review of traditional uses, phytochemistry and pharmacology of Reynoutria genus

Objectives

The genus Reynoutria belonging to the family Polygonaceae is widely distributed in the north temperate zone and used in folk medicine. It is administered as a sedative, tonic and digestive, also as a treatment for canities and alopecia. Herein, we reported a review on traditional uses, phytochemistry and pharmacology reported from 1985 up to early 2022. All the information and studies concerning Reynoutria plants were summarized from the library and digital databases (e.g. ScienceDirect, SciFinder, Medline PubMed, Google Scholar, and CNKI).

Key findings

A total of 185 articles on the genus Reynoutria have been collected. The phytochemical investigations of Reynoutria species revealed the presence of more than 277 chemical components, including stilbenoids, quinones, flavonoids, phenylpropanoids, phospholipids, lactones, phenolics and phenolic acids. Moreover, the compounds isolated from the genus Reynoutria possess a wide spectrum of pharmacology such as anti-atherosclerosis, anti-inflammatory, antioxidative, anticancer, neuroprotective, anti-virus and heart protection.

Summary

In this paper, the traditional uses, phytochemistry and pharmacology of genus Reynoutria were reviewed. As a source of traditional folk medicine, the Reynoutria genus have high medicinal value and they are widely used in medicine. Therefore, we hope our review can help genus Reynoutria get better development and utilization.

2,3,5,4′-Tetrahydroxystilbene-2-O-β-D-Glucoside improves female ovarian aging

Reduced fertility associated with normal aging may reflect the over-maturity of oocytes. It is increasingly important to reduce aging-induced infertility since recent trends show people marrying at later ages. 2,3,5,4′-Tetrahydroxystilbene-2-O-β-D-glucoside (THSG), a polyphenol extracted from Polygonum multiflorum, has been reported to have anti-inflammatory and anti-aging properties. To evaluate whether THSG can reduce aging-related ovarian damage in a female mouse model of aging, THSG was administered by gavage at a dose of 10 mg/kg twice weekly, starting at 4 weeks of age in a group of young mice. In addition, the effect of THSG in a group of aged mice was also studied in mice starting at 24 weeks of age. The number of oocytes in the THSG-fed group was higher than in the untreated control group. Although the percentage of secondary polar bodies (PB2) decreased during aging in the THSG-fed group, it decreased much more slowly than in the age-matched control group. THSG administration increased the quality of ovaries in young mice becoming aged. Western blotting analyses also indicated that CYP19, PR-B, and ER-β expressions were significantly increased in 36-week-old mice. THSG also increased oocyte numbers in aged mice compared to mice without THSG fed. Studies of qPCR and immunohistochemistry (IHC) analyses of ovaries in the aged mice groups were conducted. THSG increased gene expression of anti-Müllerian hormone (AMH), a biomarker of oocyte number, and protein accumulation in 40-week-old mice. THSG increased the expression of pgc1α and atp6, mitochondrial biogenesis-related genes, and their protein expression. THSG also attenuated the fading rate of CYP11a and CYP19 associated with sex hormone synthesis. And THSG maintains a high level of ER-β expression, thereby enhancing the sensitivity of estrogen. Our findings indicated that THSG increased or extended gene expression involved in ovarian maintenance and rejuvenation in young and aged mice. On the other hand, THSG treatments significantly maintained oocyte quantity and quality in both groups of young and aged mice compared to each age-matched control group. In conclusion, THSG can delay aging-related menopause, and the antioxidant properties of THSG may make it suitable for preventing aging-induced infertility.

Modulation of autophagy by melatonin via sirtuins in stroke: From mechanisms to therapies

Sirtuins perform an important effect on the neural cell fate following stroke. Several mechanisms that have been correlated with stroke are oxidative stress, apoptosis, necrosis and autophagy. Autophagy is usually regarded as unitary of the neural cell survival mechanisms. Recently, the importance of the sirtuins effect on autophagy by antioxidant agents for stroke treatment mentioned in various studies. One of these agents is melatonin. Melatonin can modulate autophagy by changing on sirtuin pathways. Melatonin and its metabolites adjust various sirtuins pathways related to apoptosis, proliferation, metastases, autophagy and inflammation in case of stroke. In this review, we will discuss about the modulation of autophagy by melatonin via sirtuins in stroke.

Neuroprotective Effects of Oligosaccharides From Periplaneta Americana on Parkinson’s Disease Models In Vitro and In Vivo

Parkinson’s disease (PD) is one of the neurodegenerative diseases that is characterized by obvious motor and some nonmotor symptoms. Various therapeutics failed in the effective treatment of PD because of impaired neurological function in the brain and various complications. Periplaneta Americana oligosaccharides (OPA), the main active ingredients extracted from the medicine residues of Periplaneta Americana (P. Americana), have been reported to exert anti-inflammatory effects. The purpose of this study was to evaluate the possible mechanisms of OPA against 1-methyl-4-phenylpyridinium (MPP⁺)-induced apotosis in SH-SY5Y cells and its potential neuroprotective effects in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD subacute model mice. The data demonstrated that OPA significantly reversed the MPP⁺-induced decrease in SH-SY5Y cell viability, reduced the proportion of apoptotic cells, and protected SH-SY5Y cells from apoptosis in a dose-dependent manner by regulating the expression of apoptosis-related genes. Furthermore, OPA also alleviated the motor dysfunction of PD model mice, prevented the loss of tyrosine hydroxylase positive cells, suppressed the apoptosis of substantia nigra cells, and improved the dysbiosis of gut microbiota in vivo, suggesting that OPA demonstrated a significantly neuroprotective effect on PD model mice. These results indicated that OPA might be the possibility of PD therapeutics with economic utility and high safety.

Network Pharmacology and Bioinformatics Methods Reveal the Mechanism of Berberine in the Treatment of Ischaemic Stroke

Aim

To elucidate the mechanism of action of berberine on ischaemic stroke based on network pharmacology, bioinformatics, and experimental verification.

Methods

Berberine-related long noncoding RNAs (lncRNAs) were screened from public databases. Differentially expressed lncRNAs in ischaemic stroke were retrieved from the Gene Expression Omnibus (GEO) database. GSE102541 was comprehensively analysed using GEO2R. The correlation between lncRNAs and ischaemic stroke was evaluated by the mammalian noncoding RNA-disease repository (MNDR) database. The component-target-disease network and protein-protein interaction (PPI) network of berberine in the treatment of ischaemic stroke were constructed by using network pharmacology. We then performed gene ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment analyses. Finally, according to the molecular docking analysis and the binding probability between the lncRNA and key proteins, the effectiveness of the results was further verified by in vitro experiments.

Results

After matching stroke-related lncRNAs with berberine-related lncRNAs, four genes were selected as potential targets of berberine in the treatment of ischaemic stroke. Subsequently, lncRNA H19 was identified as the potential crucial regulatory lncRNA of berberine. Here, 52 target proteins of berberine in the treatment of ischaemic stroke were identified through database mining. Through topological analysis, 20 key targets were identified which were enriched in inflammation, apoptosis, and immunity. Molecular docking results showed that MAPK8, JUN, and EGFR were central genes. Finally, in vitro experiments demonstrated that lncRNA H19, p-JNK1/JNK1, p-c-Jun/c-Jun, and EGFR expressions were significantly increased in hypoxia-treated SH-SY5Y cells and were restored by berberine treatment.

Conclusion

The potential targets and biological effects of berberine in the treatment of ischaemic stroke were predicted in this study. The lncRNA H19/EGFR/JNK1/c-Jun signalling pathway may be a key mechanism of berberine-induced neuroprotection in ischaemic stroke.

Antioxidant properties of butylated phenol with oxadiazole and hydrazone moiety at ortho position supported by DFT study

Two series of 1,3,4-oxadiazole derivatives at the sixth position of the 2,4-di-tert-butylphenol group were synthesized. The antioxidant properties were evaluated by DPPH and FRAP assays. Compound 3 showed significant antioxidant activity, while its alkyl derivatives exhibited decreased antioxidant activity in both assays. The preferential antioxidant mechanism of the reactive antioxidant molecules prepared from the further reaction of compound 3 to produce compounds 4 and 6 was investigated using density functional theory. Calculating their comprehensive reactivity descriptors was used to assess their antioxidant reactivity. According to the calculated descriptors, compounds 4c and 6d are the most reactive antioxidants within their own group compared to the other derivative moieties. The results are identical to ascorbic acid's, indicating that they have similar activity. The experimental data and the calculated descriptors are in good agreement. The nature of the substituents and their positions have a significant impact on the derivatives' antioxidant capabilities.

Two series of 1,3,4-oxadiazole derivatives at the sixth position of the 2,4-di-tert-butylphenol group were synthesized.

Tetrahydroxystilbene glucoside attenuated homocysteine-upregulated endothelin receptors in vascular smooth muscle cells via the ERK1 /2 /NF-κB signaling pathway

2,3,5,4'-Tetrahydrostilbene-2-o-β-d-glucoside (TSG) is the main active component of Polygonum multiflorum Thunb. It has effects on hypertension. However, the mechanism is unclear. Current research is devoted to exploring the mechanism of TSG improving HHcy-induced hypertension. The mice received a subcutaneous injection of Hcy in the presence or absence of TSG for 4 weeks. Blood pressure (BP) was measured using a noninvasive tail-cuff plethysmography method. Levels of plasma Hcy and endothelin-1 were measured using ELISA. Rat SMA without endothelium was cultured in a serum-free medium in the presence or absence of TSG with or without Hcy. The contractile response to sarafotoxin 6c or endothein-1 was studied using a sensitive myography. The levels of protein were detected using Western blotting. The results showed that TSG lowered HHcy-elevated BP and decreased levels of plasma Hcy and endothelin-1 in mice. Furthermore, the results showed that TSG inhibited Hcy-upregulated ET receptor expression and ET receptor-mediated contractile responses as well as the levels of p-ERK_1/2 and p-p65 in SMA. In vivo results further validate the in vitro results. In conclusion, TSG can decrease the levels of plasma Hcy and ET-1 and downregulate Hcy-upregulated ET receptors in VSMCs by inhibiting the ERK_1/2 /NF-κB/ET_B2 pathway to lower the BP.

Enhanced treatment of cerebral ischemia-Reperfusion injury by intelligent nanocarriers through the regulation of neurovascular units

Reperfusion injury is one of the major causes of disability and death caused by ischemic stroke, and drug development focuses mainly on single neuron protection. However, different kinds of cells in the neurovascular units (NVUs), including neurons, microglia and vascular endothelial cells, are pathologically changed after cerebral ischemia-reperfusion injury, resulting in an urgent need to develop a drug delivery system to comprehensively protect the kinds of cells involved in the NVU. Herein, we have constructed a c(RGDyK) peptide modified, NF-κB inhibitor caffeic acid phenethyl ester (CAPE)-loaded and reactive nitrogen species (RNS) stimuli-responsive liposomal nanocarrier (R-Lipo-CAPE) to target ischemic lesions and then remodel the NVU to reduce the progression of cerebral ischemia-reperfusion injury. The R-Lipo-CAPE liposomes were approximately 170 nm with a zeta potential of -30.8 ± 0.2 mV. The in vitro CAPE release behavior from R-Lipo-CAPE showed an RNS-dependent pattern. For in vivo studies, transient middle cerebral artery occlusion/reperfusion (MCAO) model mice treated with R-Lipo-CAPE had the least neurological impairment and decreased brain tissue damage, with an infarct area of 13%, compared with those treated with saline of 53% or free CAPE of 38%. Furthermore, microglia in the ischemic brain were polarized to the tissue-repairing M2 phenotype after R-Lipo-CAPE treatment. In addition, R-Lipo-CAPE-treated mice displayed a prominent down-regulated expression of MMP-9 and restored expression of the tight junction protein claudin-5. This proof-of-concept indicates that R-Lipo-CAPE is a promising nanomedicine for the treatment of cerebral ischemia-reperfusion injury through the regulation of neurovascular units. STATEMENT OF SIGNIFICANCE: Based on the complex mechanism and difficulty in treatment of cerebral ischemia-reperfusion injury, the overall regulation of neurovascular unit has become an extremely important target. However, little nanomedicine has been directed to remodel the neurovascular units in targeted cerebral ischemia-reperfusion injury therapy. Here, c(RGDyK) peptide modified reactive nitrogen species (RNS) stimuli-responsive liposomal nanocarrier loaded with a NF-κB inhibitor (CAPE), was designed to simultaneously regulate various cells in the microenvironment of cerebral ischemia-reperfusion injury to remodel the neurovascular units. Our in vitro and in vivo data showed that the intelligent nanocarrier exerted the ability of pathological signal stimuli-responsive drug release, cerebral ischemia-reperfusion injury site targeting and neurovascular units remodeling through reducing neuron apoptosis, regulating microglia polarization and repairing vascular endothelial cell. Overall, the intelligent liposomal drug delivery system was a promising and safe nanomedicine in the perspective of cerebral ischemia-reperfusion injury treatment.

2,3,5,4′-Tetrahydroxystilbene-2-O-β-glucoside Attenuates Reactive Oxygen Species-Dependent Inflammation and Apoptosis in Porphyromonas gingivalis-Infected Brain Endothelial Cells

We recently reported that the periodontopathic bacteria Porphyromonas gingivalis (P. gingivalis) initiates an inflammatory cascade that disrupts the balance of reactive oxygen species (ROS), resulting in apoptotic cell death in brain endothelial cells. An extract from Polygonum multiflorum Thunb., 2,3,5,4′-Tetrahydroxystilbene-2-O-β-glucoside (THSG) has been well-reported to diminish the inflammation in many disease models. However, the effects of THSG in the area of the brain–oral axis is unknown. In this study, we examined the effects of THSG in P. gingivalis-stimulated inflammatory response and apoptotic cell death in brain endothelial cells. THSG treatment remarkably lessened the upregulation of IL-1β and TNF-α proteins in bEnd.3 cells infected with P. gingivalis. Treatment of THSG further ameliorated brain endothelial cell death, including apoptosis caused by P. gingivalis. Moreover, the present study showed that the inhibitory effects on NF-κB p65 and antiapoptotic properties of THSG is through inhibiting the ROS pathway. Importantly, the ROS inhibitory potency of THSG is similar to a ROS scavenger N-Acetyl-L-Cysteine (NAC) and NADPH oxidase inhibitor apocynin. Furthermore, the protective effect of THSG from P. gingivalis infection was further confirmed in primary mouse brain endothelial cells. Taken together, this study indicates that THSG attenuates an ROS-dependent inflammatory response and cell apoptosis in P. gingivalis-infected brain endothelial cells. Our results also suggest that THSG could be a potential herbal medicine to prevent the risk of developing cerebrovascular diseases from infection of periodontal bacteria.

A Review of Pharmacology, Toxicity and Pharmacokinetics of 2,3,5,4'-Tetrahydroxystilbene-2-O-β-D-Glucoside

Polygonum multiflorum Thunb. (He-shou-wu in Chinese), a Chinese botanical drug with a long history, is widely used to treat a variety of chronic diseases in clinic, and has been given the reputation of “rejuvenating and prolonging life” in many places. 2,3,4′,5-tetrahydroxystilbene-2-O-β-D-glucoside (TSG, C₂₀H₂₂O₉) is the main and unique active ingredient isolated from Polygonum multiflorum Thunb., which has extensive pharmacological activities. Modern pharmacological studies have confirmed that TSG exhibits significant activities in treating various diseases, including inflammatory diseases, neurodegenerative diseases, cardiovascular diseases, hepatic steatosis, osteoporosis, depression and diabetic nephropathy. Therefore, this review comprehensively summarizes the pharmacological and pharmacokinetic properties of TSG up to 2021 by searching the databases of Web of Science, PubMed, ScienceDirect and CNKI. According to the data, TSG shows remarkable anti-inflammation, antioxidation, neuroprotection, cardiovascular protection, hepatoprotection, anti-osteoporosis, enhancement of memory and anti-aging activities through regulating multiple molecular mechanisms, such as NF-κB, AMPK, PI3K-AKT, JNK, ROS-NO, Bcl-2/Bax/Caspase-3, ERK1/2, TGF-β/Smad, Nrf2, eNOS/NO and SIRT1. In addition, the toxicity and pharmacokinetics of TSG are also discussed in this review, which provided direction and basis for the further development and clinical application of TSG.

Toxicity mechanism of acrolein on DNA damage and apoptosis in BEAS-2B cells: Insights from cell biology and molecular docking analyses

Acrolein is a hazardous air pollutant for humans and is responsible for many pulmonary diseases, but the underlying mechanisms have not been completely elucidated. This work is focused on the genotoxicity effects of human bronchial epithelial (BEAS-2B) cells induced by acrolein (20, 40, 80 μM). The molecular mechanism was investigated base on DNA damage and mitochondrial apoptosis pathways. The results showed that after exposure to acrolein, the cell viability, glutathione (GSH) of BEAS-2B cells were reduced. Reactive oxygen species (ROS) level significantly increased, accompanied by increased levels of DNA damage-related indicators 8-hydroxy-2 deoxyguanosine (8-OHdG), DNA content of comet tail (Tail DNA%), olive tail moment (OTM), and nucleus morphology. Cell arrested at the G2/M phase. Then, the DNA damage response (DDR) signaling pathway (Ataxia-telangiectasia-mutated (ATM) and Rad-3-related (ATR)/Chk1 and ATM/Chk2) and the consequent cell cycle checkpoints were activated. The expression of γ-H2AX was significantly increased, indicating that acrolein induced DNA double-strand breaks. Molecular docking assay showed that acrolein bound to DNA in a spontaneous process. Moreover, mitochondrial apoptosis pathway involved in apoptosis, mitochondrial membrane potential (MMP) and adenosine triphosphate (ATP) content of BEAS-2B cells were significantly reduced, and the apoptosis rate was significantly increased. The protein expression of Bax/Bcl-2 and Cleaved Caspase-3 were increased, and JNK signaling pathway was activated. All the results indicated that acrolein induced DNA damage, activated DDR and mitochondrial apoptosis pathways, which might be the pivotal factors to mediate cytotoxicity in BEAS-2B cells.

Histone Deacetylases and Their Isoform-Specific Inhibitors in Ischemic Stroke

Cerebral ischemia is the second leading cause of death in the world and multimodal stroke therapy is needed. The ischemic stroke generally reduces the gene expression due to suppression of acetylation of histones H3 and H4. Histone deacetylases inhibitors have been shown to be effective in protecting the brain from ischemic damage. Histone deacetylases inhibitors induce neurogenesis and angiogenesis in damaged brain areas promoting functional recovery after cerebral ischemia. However, the role of different histone deacetylases isoforms in the survival and death of brain cells after stroke is still controversial. This review aims to analyze the data on the neuroprotective activity of nonspecific and selective histone deacetylase inhibitors in ischemic stroke.

Heat stress aggravates oxidative stress, apoptosis, and endoplasmic reticulum stress in the cerebellum of male C57 mice

BACKGROUND

The current study was set to assess the effect of heat stress exposure on oxidative stress, apoptosis, and endoplasmic reticulum stress markers in the cerebellum of male mice.

METHODS

Fifty male C57BL/6 mice were assigned to five groups of (I) control, (II) heat stress (HS)7, (III) HS14, (IV) HS21, and (V) HS42 groups. Animals in the control group were not exposed to HS. Mice in the II-V groups were exposed to HS once a day over 7, 14, 21, and 42 days, respectively. Cerebellar reactive oxygen species (ROS) levels, expression of heat shock protein (HSP)70 and caspase 3 as well as endoplasmic reticulum stress-related proteins (PERK, p-PERK, CHOP, and Full-length ATF-6) expression were determined on the 7th, 14th, 21st, and 42nd days.

RESULTS

ROS levels and HSP70 expression increased following HS on the 14th, 21st, and 42nd days and the 7th, and 14th days with a peak level of expression on the 14th day following HS. HSP70 levels decreased afterward on the 21st and 42nd days compared with the control group. Besides, exposure to HS for 14, 21, and 42 days resulted in a significant increase in the CHOP and p-PERK levels in the cerebellum compared with the control group. Heat exposure also increased protein expression of cleaved caspase 3 and active ATF-6/Full-length ATF-6 on the 21st and 42nd days in the cerebellum compared with the control animals.

CONCLUSION

These findings indicated that chronic HS augmented oxidative stress, endoplasmic reticulum stress, and apoptosis pathways in the cerebellum of mice.

Activation of Adenosine A1 Receptor in Ischemic Stroke: Neuroprotection by Tetrahydroxy Stilbene Glycoside as an Agonist

Ischemic stroke is the main cause of death/disability, posing a great menace to human health. Though efforts to search for therapeutic drugs are ongoing, few of them have succeeded. Adenosine A₁ receptor (A1R) activation could ameliorate ischemic injury, representing a very tempting target for stroke treatment. Tetrahydroxy stilbene glycoside (TSG), a potent antioxidant from the well-known Chinese herb Polygonum multiflorum Thunb., has been reported to have notable neuroprotective activities but the underlying mechanisms are elusive. This study investigated the mechanism of TSG focusing on A1R. TSG markedly decreased mortality, neurological deficit score, cerebral infarct size and brain water content of MCAO rats, and ameliorated the disorders in purine metabolism, energy metabolism and antioxidative defense system. TSG helped the survival of SH-SY5Y cells in OGD/R by alleviating oxidative stress and glutamate release, and by maintaining calcium homeostasis. TSG effects were abolished by A1R antagonist DPCPX. Docking and binding assays confirmed the binding of TSG with A1R. In addition, TSG upregulated the A1R level lowered by MCAO and OGD/R. The downstream signals of A1R activation, ERK1/2, HIF-1α and NF-κB contributed to the neuroprotection of TSG. Moreover, void of “well-known” cardiovascular side effects of classical A1R agonists, TSG showcased its great potential for stroke treatment.

Danggui-Shaoyao-San (DSS) Ameliorates Cerebral Ischemia-Reperfusion Injury via Activating SIRT1 Signaling and Inhibiting NADPH Oxidases

Danggui-Shayao-San (DSS) is a famous Traditional Chinese Medicine formula that used for treating pain disorders and maintaining neurological health. Recent studies indicate that DSS has neuroprotective effects against ischemic brain damage but its underlining mechanisms remain unclear. Herein, we investigated the neuroprotective mechanisms of DSS for treating ischemic stroke. Adult male Sprague-Dawley (S.D.) rats were subjected to 2 h of middle cerebral artery occlusion (MCAO) plus 22 h of reperfusion. Both ethanol extract and aqueous extract of DSS (12 g/kg) were orally administrated into the rats at 30 min prior to MCAO ischemic onset. We found that 1) ethanol extract of DSS, instead of aqueous extract, reduced infarct sizes and improved neurological deficit scores in the post-ischemic stroke rats; 2) Ethanol extract of DSS down-regulated the expression of the cleaved-caspase 3 and Bax, up-regulated bcl-2 and attenuated apoptotic cell death in the ischemic brains; 3) Ethanol extract of DSS decreased the production of superoxide and peroxynitrite; 4) Ethanol extract of DSS significantly down-regulated the expression of p67^phox but has no effect on p47^phox and iNOS statistically. 5) Ethanol extract of DSS significantly up-regulated the expression of SIRT1 in the cortex and striatum of the post-ischemic brains; 6) Co-treatment of EX527, a SIRT1 inhibitor, abolished the DSS’s neuroprotective effects. Taken together, DSS could attenuate oxidative/nitrosative stress and inhibit neuronal apoptosis against cerebral ischemic-reperfusion injury via SIRT1-dependent manner.

Subanesthetic isoflurane abates ROS-activated MAPK/NF-κB signaling to repress ischemia-induced microglia inflammation and brain injury

Isoflurane (ISO) elicits protective effects on ischemia-induced brain injury. We investigated whether sub-anesthetic (0.7%) ISO post-conditioning attenuates the inflammation and apoptosis in oxygen-glucose deprivation (OGD)-insulted co-cultures (microglia and neurons) in vitro and the brain injury of the middle cerebral arterial occlusion (MCAO) rat. We demonstrated that ISO augmented the viability of OGD-treated microglia and neurons. ISO reduced the expression and activation of COX2 and iNOS in OGD-challenged microglia. ISO repressed the production of tumor necrosis factor-α, interleukin (IL)-1β, IL-6, IL-8, and monocyte chemoattractant protein-1 in OGD-exposed microglia. ISO also decreased nucleosomal fragmentation and caspase-3 activity but increased mitochondrial membrane potential in OGD-stimulated microglia and neurons. Mechanistically, ISO suppressed OGD-induced microglial inflammation by blocking ROS-regulated p38 MAPK/NF-κB signaling pathway and hampered OGD-triggered microglial apoptosis in a ROS- or NO-dependent fashion. In vivo results with MCAO rats were partly consistent with the in vitro observation. These findings indicate that sub-anesthetic ISO post-conditioning abates the inflammation and apoptosis in OGD-stimulated rat microglia and the apoptosis of OGD-exposed neurons and the brain injuries of MCAO rats, suggesting it as a potentially effective therapeutic approach for ischemic brain damages.

Silymarin and neurodegenerative diseases: Therapeutic potential and basic molecular mechanisms

BACKGROUND

Neurodegenerative diseases (NDDs) are primarily characterized by selective neuronal loss in the brain. Alzheimer's disease as the most common NDDs and the most prevalent cause of dementia is characterized by Amyloid-beta deposition, which leads to cognitive and memory impairment. Parkinson's disease is a progressive neurodegenerative disease characterized by the dramatic death of dopaminergic neuronal cells, especially in the SNc and caused alpha-synuclein accumulation in the neurons. Silymarin, an extract from seeds of Silybum marianum, administered mostly for liver disorders and also had anti-oxidant and anti-carcinogenic activities.

PURPOSE

The present comprehensive review summarizes the beneficial effects of Silymarin in-vivo and in-vitro and even in animal models for these NDDs.

METHODS

A diagram model for systematic review is utilized for this search. The research is conducted in the following databases: PubMed, Web of Science, Scopus, and Science Direct.

RESULTS

Based on the inclusion criteria, 83 studies were selected and discussed in this review.

CONCLUSION

Lastly, we review the latest experimental evidences supporting the potential effects of Silymarin, as a neuroprotective agent in NDDs.

Promotive effects of tetrahydroxystilbene glucoside on the differentiation of neural stem cells from the mesencephalon into dopaminergic neurons

Parkinson's disease (PD) is a common neurodegenerative disorder characterized by the loss of midbrain dopaminergic (DA) neurons. Neural stem cells (NSCs) are the most promising cells for cell-replacement therapy for PD. However, the poor differentiation and maturation of DA neurons and decreased cell survival after transplantation are a challenge. Tetrahydroxystilbene glucoside (2,3,5,4'-tetrahydroxystilbene-2-O-glucoside; TSG), an active component of the popular traditional Chinese medicinal plant Polygonum multiflorum Thunb, possesses multiple pharmacological actions. In this study, we determined whether TSG can induce neural stem cell (NSCs) differentiation into neurons, especially DA neurons, and the possible involvement of Wnt/β-catenin signaling pathways. Results revealed that NSCs differentiated primarily into astrocytes when cultured in 2 % serum-containing medium. However, TSG treatment during NSC differentiation in vitro increased the number of Tuj-1-positive neurons, as well as the proportion of tyrosine hydroxylase(TH)-positive cells and dopamine- transporter- positive neurons, a late marker of mature DA neurons. We also found that TSG enhanced the expression of nuclear receptor related factor 1, a transcription factor specific for the development and maintenance of midbrain DA neurons in inducing NSC differentiation into TH -immunoreactive DA neurons. Moreover, TSG upregulated the expression of Wnt/β-catenin signaling molecules (Wnt1, Wnt3a, Wnt5a, and β-catenin). However, these promoting effects were significantly inhibited by the application of IWR1, a Wnt signaling-specific blocker in culture. Our findings suggested that TSG may have potential in inducing the DA neuronal differentiation of mouse NSCs mediated by triggering the Wnt/β-catenin signaling pathway. These results indicated the possible role for TSG in the transplantation of NSCs for PD.

Collagen Nanoparticle-Mediated Brain Silymarin Delivery: An Approach for Treating Cerebral Ischemia and Reperfusion-Induced Brain Injury

Silymarin is a bioactive constituent isolated from milk thistle (Silybum marinum). Since its discovery, silymarin has been considered a gold standard drug in treating ailments related to the liver, resulting from alcohol consumption and viral hepatitis. This hepatoprotective nature of silymarin arises out of antioxidative and tissue-regenerating properties of silymarin. However, several recent studies have established the neuroprotective link of silymarin, too. Thus, the current investigation was aimed at exploring the neuroprotective effect of nanosilymarin (silymarin encapsulated inside collagen-based polymeric nanoparticulate drug delivery system). The study aimed at bringing out the role of nanoparticles in enhancing the therapeutic effect of silymarin against neuronal injury, originating out of oxidative-stress-related brain damages in focal cerebral ischemia. Collagen-based micellar nanoparticles were prepared and stabilized using 3-ethyl carbodiimide-hydrochloride (EDC-Hcl) and malondialdehyde (MDA) as crosslinkers. Nanoparticles were characterized using dynamic light scattering (DLS), transmission electron microscopy (TEM), and Fourier transform infrared (FT-IR) spectroscopy techniques, and the size of nanoparticles was found to be around 48 nm. Male albino Wistar rats were pretreated with three different doses of nanosilymarin of 10, 100, and 1,000 μg/kg b.wt and a dose of free silymarin of 100 mg/kg b.wt intraperitoneally (i.p.) for 7 days. Focal cerebral ischemia was induced using the middle cerebral artery occlusion (MCAO) model on the eighth day for 1 h followed by 24 h reperfusion. The animals were then evaluated for neurobehavioral, infarct analysis, biochemical, histopathological, and immunohistochemical studies. All the above parameters showed remarkable improvement in nanosilymarin-treated groups in comparison to the silymarin-treated group. Nanoparticle encapsulation of drug enhanced neuroprotection by increasing drug bioavailability and targeting. Thus, the present study concluded with satisfactory results, showing the critical role played by nanoparticles in improving the neuroprotection at very low drug doses.

SIRT1 Is the Target Gene for 2,3,5,4'-Tetrahydroxystilbene-2-O-β-D-Glucoside Alleviating the HUVEC Senescence

This study aimed to explore the effects of 2,3,5,4'-tetrahydroxy-stilbene-2-O-β-d-glucoside (TSG) on the senescence of human umbilical vein cells (HUVEC) induced by hydrogen peroxide (H₂O₂) and to identify the potential targets mediating its protective action. HUVEC cells pre-treated with TSG for 24 h were exposed to H₂O₂ treatment. TSG significantly decreased H₂O₂-induced cellular senescence, as indicated by reduced senescence-associated β-galactosidase (SA-β-gal) positive staining, the proportion of cells in the G1 phase, cell apoptosis, p21, and plasminogen activator inhibitor-1 (PAI-1) expression. Moreover, TSG promoted Sirtuin 1 (SIRT1) expression. When SIRT1 was inhibited by EX527 or SIRT1 siRNA, the effect of TSG is diminished according to the increased proportion of cells in the G1 phase, cell apoptosis, p21, and PAI-1 expression. Overall, our study established TSG as an anti-senescence compound that exerts its protective action by regulating SIRT1 expression.

Density Functional Theory Studies on the Antioxidant Mechanism and Electronic Properties of Some Bioactive Marine Meroterpenoids: Sargahydroquionic Acid and Sargachromanol

Certain meroterpenoids isolated from brown alga of the genus Sargassum are known to be antioxidant agents. Herein, density functional theory has been performed to analyze the preferred antioxidant mechanism of the two reactive antioxidant compounds derived from the Sargassum genus, that is, Sargahydroquinoic acid and Sargachromanol and some of their derivatives. Their global reactivity descriptors have been calculated to reveal their reactivity as an antioxidant. Molecule 1 is the most reactive antioxidant according to calculated descriptors. The results of molecule 1 are comparable to that of Trolox, suggesting their similar activity. The calculated descriptors are closely matched with experimental pieces of evidence. It has been found that hydrogen atom transfer (HAT) is more favored in gas media. Also, the effect of solvent polarity on the antioxidant activity has been explored for molecule 1. The results disclose that the polarity of the solvent increases the contribution of two other mechanisms, that is, single-electron transfer, followed by proton transfer and sequential proton loss electron transfer.

Sirt1-ROS-TRAF6 Signaling-Induced Pyroptosis Contributes to Early Injury in Ischemic Mice

Stroke is an acute cerebro-vascular disease with high incidence and poor prognosis, most commonly ischemic in nature. In recent years, increasing attention has been paid to inflammatory reactions as symptoms of a stroke. However, the role of inflammation in stroke and its underlying mechanisms require exploration. In this study, we evaluated the inflammatory reactions induced by acute ischemia and found that pyroptosis occurred after acute ischemia both in vivo and in vitro, as determined by interleukin-1β, apoptosis-associated speck-like protein, and caspase-1. The early inflammation resulted in irreversible ischemic injury, indicating that it deserves thorough investigation. Meanwhile, acute ischemia decreased the Sirtuin 1 (Sirt1) protein levels, and increased the TRAF6 (TNF receptor associated factor 6) protein and reactive oxygen species (ROS) levels. In further exploration, both Sirt1 suppression and TRAF6 activation were found to contribute to this pyroptosis. Reduced Sirt1 levels were responsible for the production of ROS and increased TRAF6 protein levels after ischemic exposure. Moreover, N-acetyl-L-cysteine, an ROS scavenger, suppressed the TRAF6 accumulation induced by oxygen-glucose deprivation via suppression of ROS bursts. These phenomena indicate that Sirt1 is upstream of ROS, and ROS bursts result in increased TRAF6 levels. Further, the activation of Sirt1 during the period of ischemia reduced ischemia-induced injury after 72 h of reperfusion in mice with middle cerebral artery occlusion. In sum, these results indicate that pyroptosis-dependent machinery contributes to the neural injury during acute ischemia via the Sirt1-ROS-TRAF6 signaling pathway. We propose that inflammatory reactions occur soon after oxidative stress and are detrimental to neuronal survival; this provides a promising therapeutic target against ischemic injuries such as a stroke.

6'"-p-Coumaroylspinosin protects PC12 neuronal cells from acrylamide-induced oxidative stress and apoptosis

6'"-p-coumaroylspinosin (P-CS) is a flavonoid isolated from Ziziphi Spinosae Semen (ZSS), whereas, the antioxidative activity has not been reported. Oxidative stress is believed to be one of the main causes of neurodegenerative disorders. In this study, the antioxidative effect of P-CS on PC12 cells was determined. The cells were treated with acrylamide (AA) in the absence or presence of P-CS, and cell apoptosis was analyzed. Interestingly, P-CS pretreatment of the cells could significantly prevent AA-induced cell death, glutathione (GSH) contents decrease, and reactive oxygen species (ROS) overproduction. Further investigation of the molecular mechanism underlying the effect of P-CS on cell apoptosis revealed that P-CS was able to suppress the expression of Bax and Bim induced by AA and inhibit the JNKs pathway. Our findings support a role of P-CS in preventing neuronal cell apoptosis induced by AA, suggesting its therapeutic potential for the treatment of neurodegenerative disorders as a medicinal supplement. PRACTICAL APPLICATIONS: Oxidative stress is believed to cause damage in subcellular organelles, nucleic acids, and alteration in protein aggregation as well as disruption of the signaling cascades associated with aging and apoptosis. A small molecule, non-poisonous natural antioxidant is needed to protect the brain from oxidative stress. Compared with western medicine, natural products carry less risk of adverse effects and are not too expensive, especially for the third-world countries. Furthermore, ZSS could be used to produce or prepare antioxidants, such as P-CS, which has been reported significant anti-oxidative activity in this study.

Pterostilbene induces Nrf2/HO-1 and potentially regulates NF-κB and JNK-Akt/mTOR signaling in ischemic brain injury in neonatal rats

Hypoxic-ischemic (HI) brain injury has a high occurrence rate of 1-4 per 1000 live births and is the leading cause of neurological disabilities. Despite the improvement in neonatal care, the effectiveness of current therapeutic strategies is limited, and thus, additional therapies with better results are of much needed. Pterostilbene is a stilbenoid possessing numerous preventive and therapeutic properties. The current study aimed to assess whether pterostilbene exerted protective effects in neonatal rats against experimentally induced ischemic brain injury. Pterostilbene was administered via oral gavage from postnatal day 3 to day 8. Rat pups that were seven-day-old were exposed to hypoxic-ischemic insult via ligation of the common carotid artery and hypoxic environment exposure. Pterostilbene treatment reduced neuronal loss and infarct volume. Pterostilbene administration regulated the NF-κB pathway, and the levels of inflammatory mediators (Nitric oxide, TNF-α, IL-1β, and IL-6) were reduced. HI-induced oxidative stress was significantly reduced by pterostilbene, as presented by decreased production of malondialdehyde and reactive oxygen species. Levels of glutathione were enhanced by pterostilbene. Pterostilbene regulated Nrf2/HO-1 and JNK expression and activated the PI3K/Akt-mTOR signals. These findings suggest that pterostilbene is a candidate compound for the treatment of neonatal HI.

Ginsenoside Rb1 reduces H2O2‑induced HUVEC dysfunction by stimulating the sirtuin‑1/AMP‑activated protein kinase pathway

Endothelial dysfunction and senescence are closely associated with cardiovascular diseases including atherosclerosis and hypertension. Ginsenoside Rb1 (Rb1), the major active constituent of ginseng, has been investigated intensively because of its anti-obesity and anti-inflammatory effects. In a previous study, hydrogen peroxide (H₂O₂) was applied to induce human umbilical vein endothelial cell (HUVEC) aging. It was demonstrated that Sirtuin-1 (SIRT1) was activated by Rb1 to protect HUVECs from H₂O₂-induced senescence. However, the mechanisms are not fully understood. The present study examined the role of AMP-activated protein kinase (AMPK), an energy sensor of cellular metabolism, in the signaling pathway of SIRT1 during H₂O₂-stimulated HUVEC aging. It was identified that Rb1 restored the H₂O₂-induced reduction of SIRT1 expression, which was consistent with our previous study, together with the activation of AMPK phosphorylation. Using compound C, an AMPK inhibitor, the role of AMPK in the protective effect of Rb1 against H₂O₂-induced HUVEC senescence was examined. It was identified that the induction of phosphorylated AMPK by Rb1 markedly increased endothelial nitric oxide synthase expression and nitric oxide production, and suppressed PAI-1 expression, which were abrogated in HUVECs pretreated with compound C. Further experiments demonstrated that nicotinamide, a SIRT1 inhibitor, downregulated the phosphorylation of AMPK and reduced the protective effects of Rb1 against H₂O₂-induced endothelial aging. Taken together, these results provide new insights into the possible molecular mechanisms by which Rb1 protects against H₂O₂-induced HUVEC senescence via the SIRT1/AMPK pathway.

Mitochondrial MPTP: A Novel Target of Ethnomedicine for Stroke Treatment by Apoptosis Inhibition

Mammalian mitochondrial permeability transition pore (MPTP), across the inner and outer membranes of mitochondria, is a nonspecific channel for signal transduction or material transfer between mitochondrial matrix and cytoplasm such as maintenance of Ca²⁺ homeostasis, regulation of oxidative stress signals, and protein translocation evoked by some of stimuli. Continuous MPTP opening has been proved to stimulate neuronal apoptosis in ischemic stroke. Meanwhile, inhibition of MPTP overopening-induced apoptosis has shown excellent efficacy in the treatment of ischemic stroke. Among of which, the potential molecular mechanisms of drug therapy for stroke has also been gradually revealed by researchers. The characteristics of multi-components or multi-targets for ethnic drugs also provide the possibility to treat stroke from the perspective of mitochondrial MPTP. The advantages mentioned above make it necessary for us to explore and clarify the new perspective of ethnic medicine in treating stroke and to determine the specific molecular mechanisms through advanced technologies as much as possible. In this review, we attempt to uncover the relationship between abnormal MPTP opening and neuronal apoptosis in ischemic stroke. We further summarized currently authorized drugs, ethnic medicine prescriptions, herbs, and identified monomer compounds for inhibition of MPTP overopening-induced ischemic neuron apoptosis. Finally, we strive to provide a new perspective and enlightenment for ethnic medicine in the prevention and treatment of stroke by inhibition of MPTP overopening-induced neuronal apoptosis.

ALDH 2 conferred neuroprotection on cerebral ischemic injury by alleviating mitochondria-related apoptosis through JNK/caspase-3 signing pathway

Past studies have indicated that the dysregulation of Aldehyde dehydrogenase 2 (ALDH2) is related to the pathogenesis of acute stroke. However, the underlying mechanisms of ALDH2-mediated acute stroke are still not well understood. Thus, our study was designed to explore the influence of ALDH2 in acute stroke and determine whether its related mechanisms are involved in regulating mitochondria-associated apoptosis modulating JNK/caspase-3 pathway. In vitro analysis on the gain and loss of ALDH2 and JNK function were performed to explore its influence on OGD/R injury and relevant signaling pathways. Our findings suggested that ALDH2 expression was significantly down-regulated in rats suffering from acute stroke and also in primary cortical cultured neurons and PC12 cells upon OGD/R stimulation. ALDH2 overexpression markedly decreased infarct size and improved neurological outcomes. Furthermore, ALDH2 overexpression significantly suppressed stroke-induced mitochondria-associated apoptosis and inhibited p-JNK activation and p-JNK/caspase-3 complex formation. Similarly, in in vitro OGD/R models, ALDH2 reintroduction not only promoted cellular viability and moderated LDH release, but also inhibited mitochondria-related apoptosis. Moreover, JNK inhibition relieved OGD/R-induced cellular injury and apoptosis while JNK activation aggravated them. Furthermore, ALDH2 overexpression and JNK inhibition significantly reduced caspase-3 activation and transcription which was triggered by OGD/R damage. Caspase-3 activation and transcription also re-elevated during activation of JNK in ALDH2-reintroduced cells. Finally, ChIP assay revealed that p-JNK was bound to caspase-3 promoter. Collectively, ALDH2 overexpression led to a significant reduction in mitochondria-related apoptosis via JNK-mediated caspase-3 activation and transcription in both in vitro and in vivo cerebral ischemia models.

Therapeutic potential of natural compounds from Chinese medicine in acute and subacute phases of ischemic stroke

Stroke is one of the leading causes of death and disability in adults worldwide, resulting in huge social and financial burdens. Extracts from herbs, especially those used in Chinese medicine, have emerged as new pharmaceuticals for stroke treatment. Here we review the evidence from preclinical studies investigating neuroprotective properties of Chinese medicinal compounds through their application in acute and subacute phases of ischemic stroke, and highlight potential mechanisms underlying their therapeutic effects. It is noteworthy that many herbal compounds have been shown to target multiple mechanisms and in combinations may exert synergistic effects on signaling pathways, thereby attenuating multiple aspects of ischemic pathology. We conclude the paper with a general discussion of the prospects for novel natural compound-based regimens against stroke.

Cytoprotective Effects of Dinitrosyl Iron Complexes on Viability of Human Fibroblasts and Cardiomyocytes

Nitric oxide (NO) is an important signaling molecule that plays a key role in maintaining vascular homeostasis. Dinitrosyl iron complexes (DNICs) generating NO are widely used to treat cardiovascular diseases. However, the involvement of DNICs in the metabolic processes of the cell, their protective properties in doxorubicin-induced toxicity remain to be clarified. Here, we found that novel class of mononuclear DNICs with functional sulfur-containing ligands enhanced the cell viability of human lung fibroblasts and rat cardiomyocytes. Moreover, DNICs demonstrated remarkable protection against doxorubicin-induced toxicity in fibroblasts and in rat cardiomyocytes (H9c2 cells). Data revealed that the DNICs compounds modulate the mitochondria function by decreasing the mitochondrial membrane potential (ΔΨm). Results of flow cytometry showed that DNICs were not affected the proliferation, growth of fibroblasts. In addition, this study showed that DNICs did not affect glutathione levels and the formation of reactive oxygen species in cells. Moreover, results indicated that DNICs maintained the ATP equilibrium in cells. Taken together, these findings show that DNICs have protective properties in vitro. It was further suggested that DNICs may be uncouplers of oxidative phosphorylation in mitochondria and protective mechanism is mainly provided by the leakage of excess charge through the mitochondrial membrane. It is assumed that the DNICs have the therapeutic potential for treating cardiovascular diseases and for decreasing of chemotherapy-induced cardiotoxicity in cancer survivors.

Tetrahydroxystilbene Glucoside Suppresses NAPDH Oxidative Stress to Mitigate Apoptosis and Autophagy Induced by Cerebral Ischemia/Reperfusion Injury in Mice

Tetrahydroxystilbene glucoside (TSG) is the active ingredient extracted from the traditional Chinese medicine Fallopia multiflora, which has extensive pharmacological activities. The current study aimed to observe the neuroprotective mechanism of TSG in the ischemia/reperfusion (I/R) brain injury-induced apoptosis and autophagy from the point of view of oxidative stress (OS). The middle cerebral artery occlusion (MCAO) model was prepared through the suture-occluded method, and TSG was administered through tail vein injection at the time of reperfusion at the doses of 3.0, 6.0, and 12.0 mg/kg. Compared with sham group, the neurological score in I/R mice was increased (P<0.05), along with remarkably elevated cerebral infarct volume (P<0.05); while TSG administration could reduce the neurological score and cerebral infarct volume (P<0.05) and improve the neuronal damage in ischemic cortex and hippocampus (P<0.05). The expression of NOX4, activated caspase-3(9), and Beclin 1 (P<0.05), as well as the LC3BII/I ratio, had been markedly elevated (P<0.05), while TSG administration could effectively suppress the expression of the above-mentioned proteins (P<0.05). In conclusion, TSG shows obvious protection against brain injury in I/R mice, and its mechanism may be related to suppressing the NADPH-induced OS and reducing neuronal apoptosis as well as autophagy.

GCN2 suppression attenuates cerebral ischemia in mice by reducing apoptosis and endoplasmic reticulum (ER) stress through the blockage of FoxO3a-regulated ROS production

Ischemic stroke is one of the leading causes of morbidity and mortality among human worldwide. Unfortunately, cerebral I/R still lacks effective therapeutic targets and strategies. In the study, we found that general control nonderepressible 2 (GCN2) expression was increased following ischemia in the ischemic penumbra in vivo and in vitro. GCN2 suppression using its significant inhibitor, GCN2iB, exhibited a protective role in cerebral I/R injury in mice, as evidenced by the improved neurological deficits and function. GCN2 inhibition with either GCN2iB or genetic knockdown led to significant reduction of pro-apoptotic protein expression, endoplasmic reticulum stress (ERS)-related protein and oxidative stress both in I/R-induced cerebral injury and oxygen-glucose deprivation and reoxygenation (OGD/R) stimulation in N2a cells. OGD/R-triggered apoptosis and ERS were significantly depended on oxidative stress in vitro. In addition, Forkhead box O 3a (FoxO3a), involved in the reactive oxygen species (ROS) production, was increased during OGD/R stimulation-regulated apoptosis and ERS, which could be abrogated by GCN2 suppression. Consistently, FoxO3a-regulated generation of ROS was markedly ameliorated upon GCN2 suppression with GCN2iB. Thereby, our findings indicated that GCN2 suppression alleviated apoptosis and ERS in cerebral ischemia through reducing FoxO3a-dependent ROS production, illustrating that GCN2 could be a promising target for the therapeutic interventions in cerebral ischemic stroke.

Effect of Polygonum Multiflorum Thunb on liver fatty acid content in aging mice induced by D-galactose

Background

Polygonum Multiflorum Thunb(PMT) has multiple biological effects, such as anti-inflammatory, lipid-lowering, anti-aging and so on. Therefore, D-galactose-induced aging mice were used to study the effect of PMT on fatty acid metabolism and its underlying mechanism.

Methods

C57BL/6 male mice were randomly divided into normal group, aging model group, PMT intragastrical administration group (high, Medium, low); model group and PMT intragastrical administration group Daily intraperitoneal injection D-galactose 800 mg·ml^{− 1}·Kg^{− 1} to establish subacute aging model; PMT intragastrical administration group at the same time to intragastrical PMT extract (1 g·ml^{− 1}·Kg^{− 1}, 0.6 g·ml^{− 1}·Kg^{− 1}, 0.3 g·ml^{− 1}·Kg^{− 1}), normal group injection and intragastrical equivalent saline for 60 consecutive days. By detecting the oxidation index of liver to judge the efficacy of PMT, gas chromatography-mass spectrometry (GC-MS) analysis was used to quantitatively analyze the fatty acid content in liver.

Results

Finally, we found that PMT improved the enzyme activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in aging mice, and reduce the enzyme activity of malondialdehyde (MDA), aspartate aminotransferase (AST) and alanine aminotransferase (ALT). The content of fatty acids such as C18:1, C18:2, C18:3 N3, C20:2 and C20:3 N3 decreased significantly in senescent mice (P < 0.05) as evidenced by GC-MS analysis, whereas, these fatty acids increased significantly after treatment of PMT (P < 0.05).

Conclusion

PMT improves the content of liver fatty acids in aging mice induced by D-galactose through, enhancing the activity of anti-oxidant enzymes.

Regulation of Toll-Like Receptor (TLR) Signaling Pathway by Polyphenols in the Treatment of Age-Linked Neurodegenerative Diseases: Focus on TLR4 Signaling

Neuronal dysfunction initiates several intracellular signaling cascades to release different proinflammatory cytokines and chemokines, as well as various reactive oxygen species. In addition to neurons, microglia, and astrocytes are also affected by this signaling cascade. This release can either be helpful, neutral or detrimental for cell survival. Toll-like receptors (TLRs) activate and signal their downstream pathway to activate NF-κB and pro-IL-1β, both of which are responsible for neuroinflammation and linked to the pathogenesis of different age-related neurological conditions. However, herein, recent aspects of polyphenols in the treatment of neurodegenerative diseases are assessed, with a focus on TLR regulation by polyphenols. Different polyphenol classes, including flavonoids, phenolic acids, phenolic alcohols, stilbenes, and lignans can potentially target TLR signaling in a distinct pathway. Further, some polyphenols can suppress overexpression of inflammatory mediators through TLR4/NF-κB/STAT signaling intervention, while others can reduce neuronal apoptosis via modulating the TLR4/MyD88/NF-κB-pathway in microglia/macrophages. Indeed, neurodegeneration etiology is complex and yet to be completely understood, it may be that targeting TLRs could reveal a number of molecular and pharmacological aspects related to neurodegenerative diseases. Thus, activating TLR signaling modulation via natural resources could provide new therapeutic potentiality in the treatment of neurodegeneration.

Behavioral defects induced by chronic social defeat stress are protected by Momordica charantia polysaccharides via attenuation of JNK3/PI3K/AKT neuroinflammatory pathway

Background

The aim of this study was to evaluate the protective effects of Momordica charantia polysaccharides (MCP) on depressive-like behaviors.

Methods

The chronic social defeat stress (CSDS) mice model was used to evaluate the effects of MCP and their underlying mechanisms. Social interaction test (SIT), sucrose preference test (SPT), and tail suspension test (TST) were performed for behavioral assessments. Expression levels of inflammation mediators and phosphatidylinositol 3-kinase (PI3K) activity were determined using commercial ELISA kits. The expression of key proteins in the c-Jun N-terminal protein kinase (JNK3)/PI3K/protein kinase B (AKT) pathway were measured using western blot and RT-PCR.

Results

The results showed that chronic administration of MCP (100, 200, 400 mg/kg/day) significantly prevented depressive-like behaviors in CSDS mice as assessed by SIT, TST and SPT. Elevated levels of proinflammatory cytokines [tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1 beta (IL-1β)], and expression of JNK3, c-Jun, P-110β proteins were observed in the hippocampus of CSDS mice. Moreover, the activity of PI3K and phosphorylation level of AKT were reduced in the hippocampus of CSDS mice. Interestingly, the administration of MCP reversed these changes. Furthermore, the protective effects of MCP on CSDS mice were partly inhibited by the PI3K inhibitor, LY294002.

Conclusions

In conclusion, the protective effects of MCP against depressive-like behaviors in CSDS mice might be due to a reduction in neuroinflammation and the down-regulation of the JNK3/PI3K/AKT pathway in the hippocampus.

Current Drugs and Potential Future Neuroprotective Compounds for Parkinson's Disease

The research progress of understanding the etiology and pathogenesis of Parkinson's disease (PD) has yet lead to the development of some clinical approaches intended to treat cognitive and behavioral symptoms, such as memory and perception disorders. Despite the major advances in different genetic causes and risk factors for PD, which share common pathways to cell dysfunction and death, there is not yet a complete model of PD that can be used to accurately predict the effect of drugs on disease progression. Clinical trials are also important to test any novel neuro-protective agent, and recently there have been great advances in the use of anti-inflammatory drugs and plant flavonoid antioxidants to protect against specific neuronal degeneration and its interference with lipid and cholesterol metabolism. The increasing knowledge of the molecular events underlying the degenerative process of PD has stimulated research to identify natural compounds capable of halting or slowing the progress of neural deterioration. Polyphenols and flavonoids, which play a neuroprotective role in a wide array of in vitro and in vivo models of neurological disorders, emerged from among the multi-target bio-agents found mainly in plants and microorganisms. This review presents a detailed overview of the multimodal activities of neuroprotective bio-agents tested so far, emphasizing their neurorescue/neuroregenerative activity. The brain-penetrating property of bioagents may make these compounds an important class of natural drugs for the treatment of neurodegenerative diseases. Although there are numerous studies demonstrating beneficial effects in the laboratory by identifying critical molecular targets, the clinical efficacy of these neuroprotective treatments remains to be proven accurately.

Tetrahydroxystilbene Glucoside (TSG) Restores the Effect of Transient Hypoxia on Reperfusion Injury in Senescent H9c2 Cells by Regulating Mitochondrial Energy Metabolism

Tetrahydroxystilbene glucoside (TSG) is extracted from a famous Chinese herbal medicine which is widely used as an antiaging agent in history. Lots of studies gave evidence that TSG exhibited benefits to brain, like improvement of learning and memory and synaptic plasticity. Moreover, the polyphenolic structure of TSG enables its capability to prevent cerebral ischemia/reperfusion injury (IRI) by reducing apoptosis and ROS/RNS generation. Due to its antioxidant profile, TSG had been demonstrated to alleviate cardiac toxicity by regulating biochemical indexes and ROS. However, whether TSG exhibited cardioprotective effects via mitochondrial energy metabolic functions, which played crucial role in IRI, remained unclear. Here, we used an in vitro aging model of cardiomyocytes to evaluate the effects of TSG on transient hypoxia-pretreated hypoxia/reoxygenation (H/R) injury and mitochondrial energy metaolism. Our results showed that TSG enhanced cardioprotective effect of transient hypoxia on H/R by reducing excessive ROS production and calcium overloading. Significant improvements of mitochondrial respiratory functions and ketone body metabolism elucidated that TSG restored the effect of transient hypoxia on H/R injury in aging cardiomyocytes via upregulating mitochondrial energy metabolism.