Protective Effect of Stachydrine Against Cerebral Ischemia-Reperfusion Injury by Reducing Inflammation and Apoptosis Through P65 and JAK2/STAT3 Signaling Pathway

Exploring stachydrine: from natural occurrence to biological activities and metabolic pathways

Stachydrine, also known as proline betaine, is a prominent constituent of traditional Chinese herb Leonurus japonicus, renowned for its significant pharmacological effects. Widely distributed in plants like Leonurus and Citrus aurantium, as well as various bacteria, stachydrine serves pivotal physiological functions across animal, plant, and bacterial kingdoms. This review aims to summarizes diverse roles and mechanisms of stachydrine in addressing cardiovascular and cerebrovascular diseases, neuroprotection, anticancer activity, uterine regulation, anti-inflammatory response, obesity management, and respiratory ailments. Notably, stachydrine exhibits cardioprotective effects via multiple pathways encompassing anti-inflammatory, antioxidant, anti-apoptotic, and modulation of calcium handling functions. Furthermore, its anti-cancer properties inhibit proliferation and migration of numerous cancer cell types. With a bi-directional regulatory effect on uterine function, stachydrine holds promise for obstetrics and gynecology-related disorders. In plants, stachydrine serves as a secondary metabolite, contributing to osmotic pressure regulation, nitrogen fixation, pest resistance, and stress response. Similarly, in bacteria, it plays a crucial osmoprotective role, facilitating adaptation to high osmotic pressure environments. This review also addresses ongoing research on the anabolic metabolism of stachydrine. While the biosynthetic pathway remains incompletely understood, the metabolic pathway is well-established. A deeper understanding of stachydrine biosynthesis holds significance for elucidating its mechanism of action, advancing the study of plant secondary metabolism, enhancing drug quality control, and fostering new drug development endeavors.

Stachydrine hydrochloride protects the ischemic heart by ameliorating endoplasmic reticulum stress through a SERCA2a dependent way and maintaining intracellular Ca2+ homeostasis

This study aimed to explore the effects and mechanism of action of stachydrine hydrochloride (Sta) against myocardial infarction (MI) through sarcoplasmic/endoplasmic reticulum stress-related injury. The targets of Sta against MI were screened using network pharmacology. C57BL/6 J mice after MI were treated with saline, Sta (6 or 12 mg kg-1) for 2 weeks, and adult mouse and neonatal rat cardiomyocytes (AMCMs and NRCMs) were incubated with Sta (10-4-10-6 M) under normoxia or hypoxia for 2 or 12 h, respectively. Echocardiography, Evans blue, and 2,3,5-triphenyltetrazolium chloride (TTC) staining were used for morphological and functional analyses. Endoplasmic reticulum stress (ERS), unfolded protein reaction (UPR), apoptosis signals, cardiomyocyte contraction, and Ca2+ flux were detected using transmission electron microscopy (TEM), western blotting, immunofluorescence, and sarcomere and Fluo-4 tracing. The ingredient-disease-pathway-target network revealed targets of Sta against MI were related to apoptosis, Ca2+ homeostasis and ERS. Both dosages of Sta improved heart function, decreased infarction size, and potentially increased the survival rate. Sta directly alleviated ERS and UPR and elicited less apoptosis in the border myocardium and hypoxic NRCMs. Furthermore, Sta upregulated sarcoplasmic reticulum Ca2+-ATPase 2a (SERCA2a) in both ischaemic hearts and hypoxic NRCMs, accompanied by restored sarcomere shortening, resting intracellular Ca2+, and Ca2+ reuptake time constants (Tau) in Sta-treated hypoxic ARCMs. However, 2,5-di-t-butyl-1,4-benzohydroquinone (BHQ) (25 μM), a specific SERCA inhibitor, totally abolished the beneficial effect of Sta in hypoxic cardiomyocytes. Sta protects the heart from MI by upregulating SERCA2a to maintain intracellular Ca2+ homeostasis, thus alleviating ERS-induced apoptosis.

Multiomics profiling of the therapeutic effect of Dan-deng-tong-nao capsule on cerebral ischemia-reperfusion injury

BACKGROUND

Stroke is a complex physiological process associated with intestinal flora dysbiosis and metabolic disorders. Dan-deng-tong-nao capsule (DDTN) is a traditional Chinese medicine used clinically to treat cerebral ischemia-reperfusion injury (CIRI) for many years. However, little is known about the effects of DDTN in the treatment of CIRI from the perspective of gut microbiota and metabolites.

PURPOSE

This study aimed to investigate the regulatory roles of DDTN in endogenous metabolism and gut microbiota in CIRI rats, thus providing a basis for clinical rational drug use and discovering natural products with potential physiological activities in DDTN for the treatment of CIRI.

METHODS

The chemical composition of DDTN in vitro and in vivo was investigated using ultra-high performance liquid chromatography-high resolution mass spectrometry (UHPLCHRMS), followed by target prediction using reverse molecular docking. Secondly, a biological evaluation of DDTN ameliorating neural damage in CIRI was performed at the whole animal level. Then, an integrated omics approach based on UHPLCHRMS and 16S rRNA sequencing was proposed to reveal the anti-CIRI effect and possible mechanism of DDTN. Finally, exploring the intrinsic link between changes in metabolite profiles, changes in the intestinal flora, and targets of components to reveal DDTN for the treatment of CIRI.

RESULTS

A total of 112 chemical components of DDTN were identified in vitro and 10 absorbed constituents in vivo. The efficacy of DDTN in the treatment of CIRI was confirmed by alleviating cerebral infarction and neurological deficits. After the DDTN intervention, 21 and 26 metabolites were significantly altered in plasma and fecal, respectively. Based on the fecal microbiome, a total of 36 genera were enriched among the different groups. Finally, the results of the network integration analysis showed that the 10 potential active ingredients of DDTN could mediate the differential expression of 24 metabolites and 6 gut microbes by targeting 25 target proteins.

CONCLUSION

This study was the first to outline the landscapes of metabolites as well as gut microbiota regulated by DDTN in CIRI rats using multi-omics data, and comprehensively revealed the systematic relationships among ingredients, targets, metabolites, and gut microbiota, thus providing new perspectives on the mechanism of DDTN in the treatment of CIRI.

Analysis of cerebrospinal fluid metabolites affected by WenDanTang based on ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry

WenDanTang (WDT) is a Chinese herbal formula used to treat various diseases, including neurodegenerative diseases. However, the neuroprotective metabolic pathways and the components involved in this process are not fully understood. In this study, we examined the neuroprotective metabolic pathways of WDT in rat brains using cerebrospinal fluid metabolomics and ultra-high-performance liquid chromatography-high-resolution mass spectrometry. Twelve rats were randomly divided into a WDT (administrated with WDT solution) and a control group. The ultra-high-performance liquid chromatography technique was used to explore the components of the WDT solution and cerebrospinal fluid, and secondary mass spectra of cerebrospinal fluid were used to identify possible brain-incorporating components after WDT. The results of the differential metabolism analysis showed that eight metabolites were typically altered (all p < 0.05). By comparing the secondary mass spectra of the cerebrospinal fluid of rats and WDT solution, two possible brain-incorporating components of WDT, stachydrine and α-methoxyphenylacetic acid, were identified. The data also suggested that WDT affects nucleotide metabolism, glutathione metabolism, and B-vitamin metabolic pathways, the central differential metabolic pathways. These data suggest that WDT protects neurons through its active components, such as stachydrine, and regulates biochemical metabolism to affect the brain's energy metabolism and antioxidant capacity.

Targeting Microglia/Macrophages Notch1 Protects Neurons from Pyroptosis in Ischemic Stroke

BACKGROUND AND AIMS

The immune-inflammatory cascade and pyroptosis play an important role in the pathogenesis of cerebral ischemia-reperfusion injury (CIRI). The maintenance of immune homeostasis is inextricably linked to the Notch signaling pathway, but whether myeloid Notch1 affects microglia polarization as well as neuronal pyroptosis in CIRI is not fully understood. This study was designed to clarify the role of myeloid Notch1 in CIRI, providing new therapeutic strategies for ischemic stroke.

METHODS AND RESULTS

Myeloid-specific Notch1 knockout (Notch1M-KO) mice and the floxed Notch1 (Notch1FL/FL) mice were subjected to middle cerebral artery occlusion (MCAO). After 3 days of CIRI, we evaluated the neurological deficit score and cerebral infarction volume. Immunofluorescence staining was used to detect the expression of Notch1 and microglial subtype markers. Cerebral infiltrating macrophages were detected by flow cytometry. RT-qPCR was used to detect pro-inflammatory cytokines. Western blot was used to detect the expression of pyroptosis related proteins. The Notch1-siRNA transfected BV2 cells were co-cultured with HT22 cells to investigate the potential mechanisms by which microglial Notch1 affects neuronal pyroptosis induced by anoxia/reoxygenation in vitro. We found that Notch1 was activated in cerebral microglia/macrophages after CIRI. Myeloid Notch1 deficiency decreased the cerebral infarct volume (24.17 ± 3.29 vs. 36.17 ± 2.27, p < 0.001), neurological function scores (2.33 ± 0.47 vs. 3.17 ± 0.37, p < 0.001) and the infiltration of peripheral monocytes/macrophages (3.26 ± 0.53 vs. 5.67 ± 0.57, p < 0.01). Strikingly, myeloid-specific Notch1 knockout alleviated pyroptosis. Compared with microglia M1, increased microglia M2 were detected in the ischemic penumbra. In parallel in vitro co-culture experiments, we found that Notch1 knockdown in microglial BV2 cells inhibited anoxia/reoxygenation-induced JAK2/STAT3 activation and pyroptosis in hippocampal neuron HT22 cells.

CONCLUSIONS

Our findings elucidate the underlying mechanism of the myeloid Notch1 signaling pathway in regulating neuronal pyroptosis in CIRI, suggesting that targeting myeloid-specific Notch1 is an effective strategy for the treatment of ischemic stroke.

Grape seed proanthocyanidins regulate mitophagy of endothelial cells and promote wound healing in mice through p-JNK/FOXO3a/ROS signal pathway

Skin wound healing is a dynamic and complex process that involves multiple physiological and cellular events. Grape seed proanthocyanidins (GSP) have strong anti-oxidation and elimination of oxygen free radicals, and have been shown to significantly promote wound healing, but the underlying mechanism remains unclear. Studies have indicated that reactive oxygen species (ROS) acts as an upstream signal to induce mitophagy, suggesting that GSP can regulate mitophagy through the signal pathway. This study aimed to investigate whether GSP regulates mitophagy by down-regulating oxidative stress to promote wound healing. In vivo, GSP treatment accelerated wound healing, granulation tissue formation, collagen deposition, and angiogenesis in mice. Moreover, GSP down-regulated ROS levels and promoted the expression of antioxidant proteins by up-regulating the expression of p-JNK/FOXO3a protein, thereby regulating the expression of mitophagy-related proteins. In vitro, 4 μg/mL GSP showed no apparent toxic effects on cells and effectively reduce the oxidative stress damage of cells induced by H2O2. Western blot and superoxide anion fluorescence probe further confirmed that GSP effectively reduced Dihydroethidium content and up-regulated the expression of antioxidant proteins by activation of p-JNK/FOXO3a protein expression, thereby regulating mitophagy. Taken together, the findings from in vitro and in vivo experiments provide new insights into the promotion of wound healing by GSP.

Regulation of microglia polarization after cerebral ischemia

Stroke ranks second as a leading cause of death and permanent disability globally. Microglia, innate immune cells in the brain, respond rapidly to ischemic injury, triggering a robust and persistent neuroinflammatory reaction throughout the disease's progression. Neuroinflammation plays a critical role in the mechanism of secondary injury in ischemic stroke and is a significant controllable factor. Microglia activation takes on two general phenotypes: the pro-inflammatory M1 type and the anti-inflammatory M2 type, although the reality is more complex. The regulation of microglia phenotype is crucial to controlling the neuroinflammatory response. This review summarized the key molecules and mechanisms of microglia polarization, function, and phenotypic transformation following cerebral ischemia, with a focus on the influence of autophagy on microglia polarization. The goal is to provide a reference for the development of new targets for the treatment for ischemic stroke treatment based on the regulation of microglia polarization.

A comprehensive review of stroke-related signaling pathways and treatment in western medicine and traditional Chinese medicine

This review provides insight into the complex network of signaling pathways and mechanisms involved in stroke pathophysiology. It summarizes the historical progress of stroke-related signaling pathways, identifying potential interactions between them and emphasizing that stroke is a complex network disease. Of particular interest are the Hippo signaling pathway and ferroptosis signaling pathway, which remain understudied areas of research, and are therefore a focus of the review. The involvement of multiple signaling pathways, including Sonic Hedgehog (SHH), nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE), hypoxia-inducible factor-1α (HIF-1α), PI3K/AKT, JAK/STAT, and AMPK in pathophysiological mechanisms such as oxidative stress and apoptosis, highlights the complexity of stroke. The review also delves into the details of traditional Chinese medicine (TCM) therapies such as Rehmanniae and Astragalus, providing an analysis of the recent status of western medicine in the treatment of stroke and the advantages and disadvantages of TCM and western medicine in stroke treatment. The review proposes that since stroke is a network disease, TCM has the potential and advantages of a multi-target and multi-pathway mechanism of action in the treatment of stroke. Therefore, it is suggested that future research should explore more treasures of TCM and develop new therapies from the perspective of stroke as a network disease.

Network pharmacology to explore the mechanism of scutellarin in the treatment of brain ischaemia and experimental verification of JAK2/STAT3 signalling pathway

Scutellarin is used to treat brain ischaemia. However, its underlying mechanism of action remains unclear. This study aimed to elucidate the potential mechanism of action of scutellarin in brain ischaemia through network pharmacology and experimental verification. The JAK2/STAT3 signalling pathway was identified and experimentally verified. Expression of JAK2/STAT3 signalling related proteins in TNC-1 astrocytes with BV-2 microglia-conditioned medium (CM), CM + lipopolysaccharide (LPS) (CM + L), and CM pretreated with scutellarin + LPS (CM + SL) was analysed by Western Blot and immunofluorescence staining. Expression levels of JAK2, p-JAK2, STAT3, and p-STAT3 were evaluated in astrocytes pre-treated with AG490. Middle cerebral artery occlusion (MCAO) in rats was performed in different experimental groups to detect expression of the above biomarkers. Network pharmacology suggested that the JAK2/STAT3 signalling pathway is one of the mechanisms by which scutellarin mitigates cerebral ischaemic damage. In TNC-1 astrocytes, p-JAK2 and p-STAT3 expression were significantly up-regulated in the CM + L group. Scutellarin promoted the up-regulation of various markers and AG490 neutralised the effect of scutellarin. In vivo, up-regulation of p-JAK2 and p-STAT3 after ischaemia is known. These results are consistent with previous reports. Scutellarin further enhanced this upregulation at 1, 3, and 7 d after MCAO. Scutellarin exerts its therapeutic effects on cerebral ischaemia by activating the astrocyte JAK2/STAT3 signalling, which provides a firm experimental basis for its clinical application.

Pasture-finishing of bison improves animal metabolic health and potential health-promoting compounds in meat

BACKGROUND

With rising concerns regarding the effects of red meat on human and environmental health, a growing number of livestock producers are exploring ways to improve production systems. A promising avenue includes agro-ecological practices such as rotational grazing of locally adapted ruminants. Additionally, growing consumer interest in pasture-finished meat (i.e., grass-fed) has raised questions about its nutritional composition. Thus, the goal of this study was to determine the impact of two common finishing systems in North American bison-pasture-finished or pen-finished on concentrates for 146 d-on metabolomic, lipidomic, and fatty acid profiles of striploins (M. longissimus lumborum).

RESULTS

Six hundred and seventy-one (671) out of 1570 profiled compounds (43%) differed between pasture- and pen-finished conditions (n = 20 animals per group) (all, P < 0.05). Relative to pasture-finished animals, the muscle of pen-finished animals displayed elevated glucose metabolites (~ 1.6-fold), triglycerides (~ 2-fold), markers of oxidative stress (~ 1.5-fold), and proteolysis (~ 1.2-fold). In contrast, pasture-finished animals displayed improved mitochondrial (~ 1.3-fold higher levels of various Krebs cycle metabolites) and carnitine metabolism (~ 3-fold higher levels of long-chain acyl carnitines) (all P < 0.05). Pasture-finishing also concentrated higher levels of phenolics (~ 2.3-fold), alpha-tocopherol (~ 5.8-fold), carotene (~ 2.0-fold), and very long-chain fatty acids (~ 1.3-fold) in their meat, while having lower levels of a common advanced lipoxidation (4-hydroxy-nonenal-glutathione; ~ 2-fold) and glycation end-product (N6-carboxymethyllysine; ~ 1.7-fold) (all P < 0.05). In contrast, vitamins B₅, B₆, and C, gamma/beta-tocopherol, and three phenolics commonly found in alfalfa were ~ 2.5-fold higher in pen-finished animals (all P < 0.05); suggesting some concentrate feeding, or grazing plants rich in those compounds, may be beneficial.

CONCLUSIONS

Pasture-finishing (i.e., grass-fed) broadly improves bison metabolic health and accumulates additional potential health-promoting compounds in their meat compared to concentrate finishing in confinement (i.e., pen-finished). Our data, however, does not indicate that meat from pen-finished bison is therefore unhealthy. The studied bison meat-irrespective of finishing practice-contained favorable omega 6:3 ratios (< 3.2), and amino acid and vitamin profiles. Our study represents one of the deepest meat profiling studies to date (> 1500 unique compounds), having revealed previously unrecognized differences in animal metabolic health and nutritional composition because of finishing mode. Whether observed nutritional differences have an appreciable effect on human health remains to be determined.

Stachydrine, a potential drug for the treatment of cardiovascular system and central nervous system diseases

Cardiovascular disease (CVD) is the leading cause of death globally and poses at significant challenge in terms of effective medical treatment. Leonurus japonicus Houtt, a traditional Chinese herb, is widely used in China for the treatment of obstetrical and gynecological disorders, including menstrual disorders, dysmenorrhea, amenorrhea, blood stasis, postpartum bleeding, and blood-related diseases such as CVD. Stachydrine, the main alkaloid component of Leonurus, has been shown to exhibit a wide range of biological activities including anti-inflammatory, antioxidant, anti-coagulant, anti-apoptotic, vasodilator, angiogenic promoter. Additionally, it has been demonstrated to have unique advantages in the prevention and treatment of CVD through regulation of various disease-related signaling pathways and molecular targets. In this comprehensive review, we examine the latest pharmacological effects and molecular mechanisms of Stachydrine in treating cardiovascular and cerebrovascular diseases. Our aim is to solid scientific basis for the development of new CVD drug formulations.

Gli2-induced lncRNA Peg13 alleviates cerebral ischemia-reperfusion injury by suppressing Yy1 transcription in a PRC2 complex-dependent manner

Endothelial cell dysfunction plays an important role in cerebral ischemia-reperfusion (I/R) injury. LncRNA Peg13 is reported to be down-regulated in brain microvascular endothelial cells (BMVECs) induced by glucose-oxygen deprivation (OGD), but the mechanism of its involvement in I/R progression remains to be further explored. Here, mouse BMVECs (bEnd.3 cells) were treated with OGD / reoxygenation (OGD/R) to simulate I/R injury in vitro. Peg13 and Gli2 expression was decreased in OGD/R-treated bEnd.3 cells. And overexpression of Peg13 or Gli2 prevented OGD/R-induced reduction in cell migration and angiogenesis, as well as upregulation in cell apoptosis and oxidative stress levels. Mechanism exploration showed that Gli2 promoted the transcription of Peg13. And Peg13 repressed Yy1 transcription by binding to Ezh2 (a key subunit of PRC2 complex) and inducing the enrichment of H3K27me3 in Yy1 promoter region, thereby suppressing the transcriptional inhibition effect of Yy1 on Notch3 and promoting the expression of Notch3. Consistently, Notch3 overexpression hindered OGD/R-induced endothelium dysfunction. In addition, a brain I/R injury model was established using middle cerebral artery occlusion surgery. And lentivirus-mediated Gli2 and Peg13 overexpression vectors were injected into mice via the lateral ventricle one week before surgery. The results showed that overexpression of Peg13 or Gli2 alleviated I/R-induced neurological deficit, cerebral infarct and cerebral edema. And simultaneous overexpression of Peg13 and Gli2 showed a better protective effect than overexpression of Gli2 or Peg13 alone. In conclusion, Peg13 regulated by Gli2 inhibits Yy1 transcription in a PCR2 complex-dependent manner, and blocks the transcriptional repression of Notch3 by Yy1, thereby exerting neuroprotective effects on cerebral I/R injury.

Ischemic Stroke Impacts the Gut Microbiome, Ileal Epithelial and Immune Homeostasis

Ischemic stroke critically impacts neurovascular homeostasis, potentially resulting in neurological disorders. However, the mechanisms through which stroke-induced inflammation modifies the molecular and metabolic circuits, particularly in ileal epithelial cells (iECs), currently remain elusive. Using multiomic approaches, we illustrated that stroke impaired the ileal microbiome and associated metabolites, leading to increased inflammatory signals and altered metabolites, potentially deteriorating the iEC homeostasis. Bulk transcriptomic and metabolomic profiling demonstrated that stroke enhanced fatty acid oxidation while reducing the tricarboxylic acid (TCA) cycle in iECs within the first day after stroke. Intriguingly, single-cell RNA sequencing analysis revealed that stroke dysregulated cell-type-specific gene responses within iECs and reduced frequencies of goblet and tuft cells. Additionally, stroke augmented interleukin-17A+ γδ T cells but decreased CD4+ T cells in the ileum. Collectively, our findings provide a comprehensive overview of stroke-induced intestinal dysbiosis and unveil responsive gene programming within iECs with implications for disease development.

Chrysophanol facilitates long-term neurological recovery through limiting microglia-mediated neuroinflammation after ischemic stroke in mice

BACKGROUND

Inflammation plays an important role in ischemic brain injury and affects brain recovery and neuroplasticity. Chrysophanol (CHR), has attracted attention for its protective effects through immunomodulatory and anti-inflammatory properties. However, the effect of CHR for brain recovery and neuroplasticity is not clear. The current study aimed to investigate the effect of CHR in the chronic phase of stroke in mice, and to elucidate the underlying mechanisms.

METHODS

C57BL/6 mice were subjected to treatment with Vehicle or CHR immediately through intraperitoneal injection daily for 14 d after distal middle cerebral artery occlusion (dMCAO). Neurological deficits were monitored up to 28 days after stroke. Nissl and Golgi stain, neural plasticity, and microglia-associated inflammatory cytokines were detected. Primary cortical neuron and BV2 microglia cell lines were employed to explore the underlying mechanism in vitro.

RESULTS

Compared with Vehicle group, CHR mitigated the histological damage, facilitated the neural plasticity and improved the neurological function up to 4 weeks after stroke. In vitro, CHR promoted the complexity of neurons and the spine density by modulating microglial polarization and reducing the expression of microglia-associated inflammatory cytokines, especially IL-6. In vivo, microglia activation and inflammatory cytokines were significantly increased after dMCAO and downregulated by CHR. Further investigation showed STAT3 is the major downstream effector of IL-6 signaling.

CONCLUSIONS

CHR ameliorated microenvironment for neural plasticity and exhibited neuroprotection via arresting microglia toward pro-inflammatory phenotype and downregulation of the expressions of pro-inflammatory cytokines, especially of IL-6. IL-6-STAT3 signaling might be CHR's therapeutic target for neuroinflammatory responses after stroke.

Biphasic effects of statins on neuron cell functions under oxygen-glucose deprivation and normal culturing conditions via different mechanisms

While there is a growing interest in the use of statins, HMG‐CoA reductase inhibitors, to treat neurodegenerative diseases, statins are associated with conflicting effects within the central nervous system (CNS) without clear evidence of the underlying mechanisms. This study systematically investigated effects of four statins (atorvastatin, pitavastatin, cerivastatin, and lovastatin) on neuronal cells under pathological condition using an in vitro model depicting ischemic injury, as well as tested under physiological condition. All four statins at micromolar concentrations display toxic effects on neuron cells under physiological condition. Atorvastatin and cerivastatin but not pitavastatin or lovastatin at nanomolar concentrations display protective effects on neuron cells under ischemic injury condition, via decreased ischemic injury‐induced oxidative stress, oxidative damage, and inflammation. Mechanistically, atorvastatin, pitavastatin, and lovastatin induces neuron cell apoptosis via prenylation‐independent manner. Other mechanisms are involved in the pro‐apoptotic effect of cerivastatin. Prenylation is not involved in the protective effects of statins under ischemic injury condition. Our work provides better understanding on the multiple differential effects of statins on neuron cells under physiological condition and ischemic injury, and elucidate their underlying mechanisms, which may be of relevance to the influence of statins in CNS.

Ac2-26 attenuates hepatic ischemia-reperfusion injury in mice via regulating IL-22/IL-22R1/STAT3 signaling

Hepatic ischemia-reperfusion injury (HIRI) is one of the major sources of mortality and morbidity associated with hepatic surgery. Ac2-26, a short peptide of Annexin A1 protein, has been proved to have a protective effect against IRI. However, whether it exerts a protective effect on HIRI has not been reported. The HIRI mice model and the oxidative damage model of H₂O₂-induced AML12 cells were established to investigate whether Ac2-26 could alleviate HIRI by regulating the activation of IL-22/IL-22R1/STAT3 signaling. The protective effect of Ac2-26 was measured by various biochemical parameters related to liver function, apoptosis, inflammatory reaction, mitochondrial function and the expressions of IL-22, IL-22R1, p-STAT3^Tyr705. We discovered that Ac2-26 reduced the Suzuki score and cell death rate, and increased the cell viability after HIRI. Moreover, we unraveled that Ac2-26 significantly decreased the number of apoptotic hepatocytes, and the expressions of cleaved-caspase-3 and Bax/Bcl-2 ratio. Furthermore, HIRI increased the contents of malondialdehyde (MDA), NADP⁺/NADPH ratio and reactive oxygen species (ROS), whereas Ac2-26 decreased them significantly. Additionally, Ac2-26 remarkably alleviated mitochondria dysfunction, which was represented by an increase in the adenosine triphosphate (ATP) content and mitochondrial membrane potential, a decrease in mitochondrial DNA (mtDNA) damage. Finally, we revealed that Ac2-26 pretreatment could significantly inhibit the activation of IL-22/IL22R1/STAT3 signaling. In conclusion, this work demonstrated that Ac2-26 ameliorated HIRI by reducing oxidative stress and inhibiting the mitochondrial apoptosis pathway, which might be closely related to the inhibition of the IL-22/IL22R1/STAT3 signaling pathway.

γ-Glutamylcysteine Exerts Neuroprotection Effects against Cerebral Ischemia/Reperfusion Injury through Inhibiting Lipid Peroxidation and Ferroptosis

Ferroptosis is a non-apoptotic form of cell death driven by iron-dependent lipid peroxidation. Recent evidence indicates that inhibiting ferroptosis could alleviate cerebral ischemia/reperfusion (CIR) injury. γ-glutamylcysteine (γ-GC), an intermediate of glutathione (GSH) synthesis, can upregulate GSH in brains. GSH is the co-factor of glutathione peroxidase 4 (GPX4), which is the negative regulator of ferroptosis. In this study, we explored the effect of γ-GC on CIR-induced neuronal ferroptosis and brain injury. We found that γ-GC significantly reduced the volume of cerebral infarction, decreased the loss of neurons and alleviated neurological dysfunction induced by CIR in rats. Further observation showed that γ-GC inhibited the CIR-caused rupture of the neuronal mitochondrial outer membrane and the disappearance of cristae, and decreased Fe2+ deposition and lipid peroxidation in rat cerebral cortices. Meanwhile, γ-GC altered the expression of some ferroptosis-related proteins in rat brains. Mechanistically, γ-GC increased the expression of GSH synthetase (GSS) for GSH synthesis via protein kinase C (PKC)ε-mediated activation of nuclear factor erythroid 2-related factor (Nrf2). Our findings suggest that γ-GC not only serves as a raw material but also increases the GSS expression for GSH synthesis against CIR-induced lipid peroxidation and ferroptosis. Our study strongly suggests that γ-GC has potential for treating CIR injury.

Stachydrine exhibits a novel antiplatelet property and ameliorates platelet-mediated thrombo-inflammation

BACKGROUND

Platelets are versatile anucleate cells involved in thrombosis as well as inflammation. Stachydrine (STA), a major bioactive compound extracted from Motherwort, has multiple pharmacological properties. Nevertheless, the significance of STA in platelet regulation and whether STA could ameliorate platelet-mediated thrombo-inflammation still remain elusive.

METHODS

Human platelets were used to assess the regulatory effects of STA on platelet activation and interactions with neutrophils in vitro. FeCl₃ injury-induced carotid/mesenteric thrombosis and collagen/epinephrine-induced pulmonary thromboembolism model were used to explore whether STA could regulate thrombosis in vivo. Furthermore, a cecal ligation and puncture-induced sepsis model was employed to investigate the role of STA in thrombo-inflammatory diseases.

RESULTS

STA markedly suppressed platelet activation represented by aggregation, secretion, αIIbβ3-mediated signaling events and calcium mobilization, etc. by inhibiting agonists-induced activation signaling and potentiating cGMP-dependent inhibitory signaling. Mice receiving STA-treated platelets were less susceptible to thrombosis in vivo. In addition, decreased platelet-neutrophil interactions including platelet-neutrophil aggregates and neutrophil extracellular traps, and alleviative sepsis-induced multiorgan damage were observed due to STA-mediated platelet inhibition.

CONCLUSION

This study suggested the potential therapeutic role of STA in thrombotic and thrombo-inflammatory disorders.

Vitamin B12 Regulates the Transcriptional, Metabolic, and Epigenetic Programing in Human Ileal Epithelial Cells

Vitamin B12 (VB12) is a micronutrient that is essential for DNA synthesis and cellular energy production. We recently demonstrated that VB12 oral supplementation coordinates ileal epithelial cells (iECs) and gut microbiota functions to resist pathogen colonization in mice, but it remains unclear whether VB12 directly modulates the cellular homeostasis of iECs derived from humans. Here, we integrated transcriptomic, metabolomic, and epigenomic analyses to identify VB12-dependent molecular and metabolic pathways in human iEC microtissue cultures. RNA sequencing (RNA-seq) revealed that VB12 notably activated genes involved in fatty acid metabolism and epithelial cell proliferation while suppressing inflammatory responses in human iECs. Untargeted metabolite profiling demonstrated that VB12 facilitated the biosynthesis of amino acids and methyl groups, particularly S-adenosylmethionine (SAM), and supported the function of the mitochondrial carnitine shuttle and TCA cycle. Further, genome-wide DNA methylation analysis illuminated a critical role of VB12 in sustaining cellular methylation programs, leading to differential CpG methylation of genes associated with intestinal barrier function and cell proliferation. Together, these findings suggest an essential involvement of VB12 in directing the fatty acid and mitochondrial metabolisms and reconfiguring the epigenome of human iECs to potentially support cellular oxygen utilization and cell proliferation.

Arginine regulates inflammation response-induced by Fowl Adenovirus serotype 4 via JAK2/STAT3 pathway

Background

Fowl Adenovirus serotype 4 (FAdV-4) infection causes severe inflammatory response leading to hepatitis-hydropericardium syndrome (HHS) in poultry. As an essential functional amino acid of poultry, arginine plays a critical role in anti-inflammatory and anti-oxidative stress.

Results

In this study, the differential expression genes (DEGs) were screened by transcriptomic techniques, and the DEGs in gene networks of inflammatory response-induced by FAdV-4 in broiler’s liver were analyzed by Kyoto encyclopedia of genes and genomes (KEGG) enrichment. The results showed that the cytokines pathway and JAK/STAT pathway were significantly enriched, in which the DEGs levels of IL-6, IL-1β, IFN-α, JAK and STAT were significantly up-regulated after FAdV-4 infection. It was further verified with real-time fluorescence quantitative polymerase chain reaction (Real-time qPCR) and Western blotting (WB) in vitro and in vivo. The findings demonstrated that FAdV-4 induced inflammatory response and activated JAK2/STAT3 pathway. Furthermore, we investigated whether arginine could alleviate the liver inflammation induced by FAdV-4. After treatment with 1.92% arginine level diet to broilers or 300 μg/mL arginine culture medium to LMH cell line with FAdV-4 infection at the same time, we found that the mRNA levels of IL-6, IL-1β, IFN-α and the protein levels of p-JAK2, p-STAT3 were down-regulated, compared with FAdV-4 infection group. Furthermore, we confirmed that the inflammation induced by FAdV-4 was ameliorated by pre-treatment with JAK inhibitor AG490 in LMH cells, and it was further alleviated in LMH cells treatment with AG490 and ARG.

Conclusions

These above results provide new insight that arginine protects hepatocytes against inflammation induced by FAdV-4 through JAK2/STAT3 signaling pathway.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-022-03282-9.

Gap Junction Protein Connexin 43 as a Target Is Internalized in Astrocyte Neurotoxicity Caused by Di-(2-ethylhexyl) Phthalate

Di-(2-ethylhexyl) phthalate (DEHP) is widely used as a plasticizer in plastic products, consumer products, and packaging materials. It is of great health concern in both animals and humans as it released into the environment and entered into the body from plastic products over time, thereby resulting in neurotoxicity. As a pivotal regulator of the central nervous system (CNS), astrocytes, are crucial for maintaining brain homeostasis. Nevertheless, the underlying reason for astrocyte neurotoxicity due to DEHP exposure remains incompletely understood. Here, using an in vivo model of neurotoxicity in quail, this study summarizes that Cx43 is internalized by phosphorylation and translocated to the nucleus as a consequence of DEHP exposure in astrocytes. This study further demonstrated that astrocytes transformed to pro-inflammatory status and induced the formation of autophagosomes. Of note, integrated immunofluorescent codetection approaches revealed an overexpression of the glial fibrillary acidic protein (GFAP) and down-expression of Cx43 in astrocytes. Therefore, in terms of neurotoxicity, this experiment in vivo models directly linked Cx43 internalization to autophagy and neuroinflammation and ultimately locked these changes to the astrocytes of the brain. These findings unveil a potential approach targeting Cx43 internalization for the treatment of neurodegeneration caused by DEHP exposure in astrocytes.

Untargeted Metabolomic Profiling and Antioxidant Capacities of Different Solvent Crude Extracts of Ephedra foeminea

Ephedra foeminea is a traditional medicinal plant used in the Eastern Mediterranean region. This study aims to investigate the chemical profiles of different solvent extracts of E. foeminea via an untargeted metabolomics approach, alongside determining their antioxidant capacities. E. foeminea samples collected from Jordan were macerated in solvents of varying polarities; dichloromethane/methanol, methanol, ethanol, ethyl acetate, and acetone. The crude extracts were subjected to comprehensive chemical profiling and metabolomics study using Gas chromatography–Mass spectrometry (GC–MS), Liquid chromatography–Mass spectrometry (LC–MS), and Nuclear Magnetic Resonance (NMR). The obtained data were analyzed using Venn diagrams, Principle Component Analysis (PCA), and Metabolite Enrichment Set Analysis (MESA). ABTS assay was performed to measure the crude extracts’ antioxidant activity. MESA revealed the dominant chemical groups as amino acids, fatty acids, carboxylic acids, and carbohydrates. Results indicated that dichloromethane/methanol and methanolic extracts had the most distinct composition as well as the most unique compounds. The methanolic extract had the most potency (IC50 249.6 µg/mL) in the ABTS assay. However, no significant differences were found. In conclusion, solvents influenced the recovery of metabolites in E. foeminea and the antioxidant activity of the E. foeminea methanolic extract could be correlated to the abundant presence of diverse bioactive compounds.

The Signaling Pathways and Targets of Natural Compounds from Traditional Chinese Medicine in Treating Ischemic Stroke

Ischemic stroke (IS) is a common neurological disorder associated with high disability rates and mortality rates. At present, recombinant tissue plasminogen activator (r-tPA) is the only US(FDA)-approved drug for IS. However, due to the narrow therapeutic window and risk of intracerebral hemorrhage, r-tPA is currently used in less than 5% of stroke patients. Natural compounds have been widely used in the treatment of IS in China and have a wide range of therapeutic effects on IS by regulating multiple targets and signaling pathways. The keywords "ischemia stroke, traditional Chinese Medicine, Chinese herbal medicine, natural compounds" were used to search the relevant literature in PubMed and other databases over the past five years. The results showed that JAK/STAT, NF-κB, MAPK, Notch, Nrf2, and PI3K/Akt are the key pathways, and SIRT1, MMP9, TLR4, HIF-α are the key targets for the natural compounds from traditional Chinese medicine in treating IS. This study aims to update and summarize the signaling pathways and targets of natural compounds in the treatment of IS, and provide a base of information for the future development of effective treatments for IS.

Metabolomic Profiling of Respiratory Muscles and Lung in Response to Long-Term Controlled Mechanical Ventilation

Critical illness myopathy (CIM) and ventilator-induced diaphragm dysfunction (VIDD) are characterized by severe muscle wasting, muscle paresis, and extubation failure with subsequent increased medical costs and mortality/morbidity rates in intensive care unit (ICU) patients. These negative effects in response to modern critical care have received increasing attention, especially during the current COVID-19 pandemic. Based on experimental and clinical studies from our group, it has been hypothesized that the ventilator-induced lung injury (VILI) and the release of factors systemically play a significant role in the pathogenesis of CIM and VIDD. Our previous experimental/clinical studies have focused on gene/protein expression and the effects on muscle structure and regulation of muscle contraction at the cell and motor protein levels. In the present study, we have extended our interest to alterations at the metabolomic level. An untargeted metabolomics approach was undertaken to study two respiratory muscles (diaphragm and intercostal muscle) and lung tissue in rats exposed to five days controlled mechanical ventilation (CMV). Metabolomic profiles in diaphragm, intercostal muscles and lung tissue were dramatically altered in response to CMV, most metabolites of which belongs to lipids and amino acids. Some metabolites may possess important biofunctions and play essential roles in the metabolic alterations, such as pyruvate, citrate, S-adenosylhomocysteine, alpha-ketoglutarate, glycerol, and cysteine. Metabolic pathway enrichment analysis identified pathway signatures of each tissue, such as decreased metabolites of dipeptides in diaphragm, increased metabolites of branch-chain amino acid metabolism and purine metabolism in intercostals, and increased metabolites of fatty acid metabolism in lung tissue. These metabolite alterations may be associated with an accelerated myofibrillar protein degradation in the two respiratory muscles, an active inflammatory response in all tissues, an attenuated energy production in two respiratory muscles, and enhanced energy production in lung. These results will lay the basis for future clinical studies in ICU patients and hopefully the discovery of biomarkers in early diagnosis and monitoring, as well as the identification of future therapeutic targets.

Lavender protects H9c2 cardiomyocytes against oxygen-glucose deprivation (OGD)-induced injury via targeting the JAK2/STAT3 pathway

Objectives

This study was conducted to examine the therapeutic effects of lavender oil (LO) against oxygen-glucose deprivation (OGD)-induced injury in vitro model.

Materials and Methods

In this study, the OGD model was induced in the H9C2 cell line, and then the cells were treated with LO (10, 100, 1000, and 10000 μg/ml). The anti-inflammatory activity of LO (JAK2/STAT3) was evaluated by immunocytochemical assay. Likewise, the p-ERK/ERK level was measured by western blotting.

Results

Compared with only the OGD-induced injury model, cell survival increased after treatment with LO. Our results showed that 100 μg/ml of LO significantly decreased the expression of Jak2/Stat3 and the apoptotic activity 72 hr after reperfusion compared with the control group. Likewise, significant increases were observed in p-ERK/ERK in LO-treated groups.

Conclusion

Collectively, these findings confirm that LO can be a good candidate to reduce OGD-induced injury in the H9C2 cell line through targeting Jak2/Stat3 and ERK pathways.

Neuroprotective and Anti-Inflammatory Effect of Pterostilbene Against Cerebral Ischemia/Reperfusion Injury via Suppression of COX-2

Background: The incidence of cerebral ischemia disease leading cause of death in human population worldwide. Treatment of cerebral ischemia remains a clinical challenge for researchers and mechanisms of cerebral ischemia remain unknown. During the cerebral ischemia, inflammatory reaction and oxidative stress plays an important role. The current investigation scrutinized the neuroprotective and anti-inflammatory role of pterostilbene against cerebral ischemia in middle cerebral artery occlusion (MCAO) rodent model and explore the underlying mechanism.

Methods: The rats were divided into following groups viz., normal, sham, MCAO and MCAO + pterostilbene (25 mg/kg) group, respectively. The groups received the oral administration of pterostilbene for 30 days followed by MCAO induction. The neurological score, brain water content, infarct volume and Evan blue leakage were estimated. Hepatic, renal, heart, inflammatory cytokines and inflammatory mediators were estimated.

Results: Pterostilbene treatment significantly (p < 0.001) improved the body weight and suppressed the glucose level and brain weight. Pterostilbene significantly (p < 0.001) reduced the hepatic, renal and heart parameters. Pterostilbene significantly (p < 0.001) decreased the level of glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD) and decreased the level of malonaldehyde (MDA), 8-Hydroxy-2′-deoxyguanosine (8-OHdG). Pterostilbene significantly (p < 0.001) inflammatory cytokines and inflammatory parameters such as cyclooxygenase-2 (COX-2), inducible nitric oxidase synthase (iNOS) and prostaglandin (PGE₂). Pterostilbene significantly (p < 0.001) down-regulated the level of metalloproteinases (MMP) such as MMP-2 and MMP-9. Pterostilbene suppressed the cellular swelling, cellular disintegration, macrophage infiltration, monocyte infiltration and polymorphonuclear leucocyte degranulation in the brain.

Conclusion: In conclusion, Pterostilbene exhibited the neuroprotective effect against cerebral ischemia in rats via anti-inflammatory mechanism.

An Integrated Analysis of Network Pharmacology and Experimental Validation to Reveal the Mechanism of Chinese Medicine Formula Naotaifang in Treating Cerebral Ischemia-Reperfusion Injury

BACKGROUND

Cerebral ischemia-reperfusion injury (CIRI) is a crucial factor leading to a poor prognosis for ischemic stroke patients. As a novel Chinese medicine formula, Naotaifang (NTF) was proven to exhibit a neuroprotective effect against ischemic stroke, clinically, and to alleviate CIRI in animals. However, the mechanisms underlying the beneficial effect have not been fully elucidated.

METHODS

In this study, we combined a network pharmacology approach and an in vivo experiment to explore the specific effects and underlying mechanisms of NTF in the treatment of ischemia-reperfusion injury. A research strategy based on network pharmacology, combining target prediction, network construction, gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, and molecular docking was used to predict the targets of NTF in treating the ischemic stroke and CIRI. On the other hand, we used HPLC and HRMS to identify biologically active components of NTF. Middle cerebral artery occlusion models in rats were utilized to evaluate the effect and the underlying mechanisms of NTF against CIRI after ischemic stroke.

RESULTS

Network pharmacology analysis revealed 43 potential targets and 14 signaling pathways for the treatment of NTF against CIRI after ischemic stroke. Functional enrichment analysis showed that a STAT3/PI3K/AKT signaling pathway serves as the target for in vivo experimental study validation. The results of animal experiments showed that NTF significantly alleviated CIRI by decreasing neurological score, infarct volume, numbers of apoptotic neuronal cells, increasing density of dendritic spines and survival of neurons. Furthermore, NTF could increase the expression of p-STAT3, PI3K, p-AKT. In addition, the detection of apoptosis-related factors showed that the NTF could raise the expression of Bcl-2 and reduce the expression of Bax.

CONCLUSION

This network pharmacological and experimental study indicated that NTF, as a therapeutic candidate for the management of CIRI following ischemic stroke, may exert a protective effect through the STAT3/PI3K/AKT signaling pathway.

Phenothiazine Inhibits Neuroinflammation and Inflammasome Activation Independent of Hypothermia After Ischemic Stroke

A depressive or hibernation-like effect of chlorpromazine and promethazine (C + P) on brain activity was reported to induce neuroprotection, with or without induced-hypothermia. However, the underlying mechanisms remain unclear. The current study evaluated the pharmacological function of C + P on the inhibition of neuroinflammatory response and inflammasome activation after ischemia/reperfusion. A total of 72 adult male Sprague-Dawley rats were subjected to 2 h middle cerebral artery occlusion (MCAO) followed by 6 or 24 h reperfusion. At the onset of reperfusion, rats received C + P (8 mg/kg) with temperature control. Brain cell death was detected by measuring CD68 and myeloperoxidase (MPO) levels. Inflammasome activation was measured by mRNA levels of NLRP3, IL-1β, and TXNIP, and protein quantities of NLRP3, IL-1β, TXNIP, cleaved-Caspase-1, and IL-18. Activation of JAK2/STAT3 pathway was detected by the phosphorylation of STAT3 (p-STAT3) and JAK2 (p-JAK2), and the co-localization of p-STAT3 and NLRP3. Activation of the p38 pathway was assessed with the protein levels of p-p38/p38. The mRNA and protein levels of HIF-1α, FoxO1, and p-FoxO1, and the co-localization of p-STAT3 with HIF-1α or FoxO1 were quantitated. As expected, C + P significantly reduced cell death and attenuated the neuroinflammatory response as determined by reduced CD68 and MPO. C + P decreased ischemia-induced inflammasome activation, shown by reduced mRNA and protein expressions of NLRP3, IL-1β, TXNIP, cleaved-Caspase-1, and IL-18. Phosphorylation of JAK2/STAT3 and p38 pathways and the co-localization of p-STAT3 with NLRP3 were also inhibited by C + P. Furthermore, mRNA levels of HIF-1α and FoxO1 were decreased in the C + P group. While C + P inhibited HIF-1α protein expression, it increased FoxO1 phosphorylation, which promoted the exclusion of FoxO1 from the nucleus and inhibited FoxO1 activity. At the same time, C + P reduced the co-localization of p-STAT3 with HIF-1α or FoxO1. In conclusion, C + P treatment conferred neuroprotection in stroke by suppressing neuroinflammation and NLRP3 inflammasome activation. The present study suggests that JAK2/STAT3/p38/HIF-1α/FoxO1 are vital regulators and potential targets for efficacious therapy following ischemic stroke.

Anti-Inflammatory Dipeptide, a Metabolite from Ambioba Secretion, Protects Cerebral Ischemia Injury by Blocking Apoptosis Via p-JNK/Bax Pathway

MQ (l-methionyl-l-glutamic acid), anti-inflammatory dipeptide, is one of the metabolites of monocyte locomotion inhibitory factor, a thermostable pentapeptide secreted by Entamoeba histolytica. Monocyte locomotion inhibitory factor injection has been approved as an investigational drug for the potential neural protection in acute ischemic stroke. This study further investigated the neuroprotective effect of MQ in ischemic brain damage. Ischemia-reperfusion injury of the brain was induced in the rat model by middle cerebral artery occlusion. 2,3,5-triphenyltetrazolium chloride staining assay was used to measure cerebral infarction areas in rats. Laser Doppler measurement instrument was used to detect blood flow changes in the rat model. Nissl staining and NeuN staining were utilized to observe the numbers and structures of neuron cells, and the pathological changes in the brain tissues were examined by hematoxylin–eosin staining. Terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling (TUNEL) staining was used to assess cell apoptosis. The changes in oxidative stress indexes, superoxide dismutase and malondialdehyde (MDA), were measured in serum. Methyl thiazolyl tetrazolium was used to measure the survival rates of PC12 cells. Flow cytometry assessed the apoptosis rates and the levels of reactive oxygen species. Real-time PCR was used to evaluate the mRNA expression levels, and Western blotting was used to analyze the changes in protein levels of p-JNK, Bax, cleaved Caspase3. We revealed that MQ improved neurobehavior, decreased cerebral infarction areas, altered blood flow volume, and the morphology of the cortex and hippocampus. On the other hand, it decreased the apoptosis of cortical neurons and the levels of MDA, and increased the levels of superoxide dismutase. In vitro studies demonstrated that MQ enhanced the cell survival rates and decreased the levels of reactive oxygen species. Compared to the oxygen-glucose deprivation/reperfusion group, the protein and mRNA expressions of p-JNK, Bax, cleaved Caspase3 was decreased significantly. These findings suggested that MQ exerts a neuroprotective effect in cerebral ischemia by blocking apoptosis via the p-JNK/Bax pathway.

IL-27 Protects the Brain from Ischemia-Reperfusion Injury via the gp130/STAT3 Signaling Pathway

The occurrence of ischemia-reperfusion (I/R) injury leads to dysfunction as well as high rates of morbidity and mortality in stroke, and new effective therapeutic strategies for I/R are still needed. We investigated the effect of IL-27 on I/R injury-induced neurological function impairment, cerebral infarction volume and variation in levels of inflammatory factors in mice with middle cerebral artery occlusion (MCAO), as well as concentration of LDH and neuronal apoptosis in a neuron oxygen-glucose deprivation and reperfusion (OGD/R) model mediated by gp130/STAT3 signaling in vitro. Our results indicated that IL-27 could bind to its receptor of gp130 to attenuate the I/R injury-induced impairment function and cerebral infarction volume, and decrease inflammatory cytokines TNF-α, IL-1β and MCP-1 but increase anti-inflammatory factors IL-10 and TGF-β in vivo, while inhibiting LDH leakage and neuronal apoptosis through activation of STAT3 to antagonize I/R induction. Our results suggest that IL-27 may protect the brain from I/R injury through the gp130/STAT3 signaling pathway.

The bidirectional role of the JAK2/STAT3 signaling pathway and related mechanisms in cerebral ischemia-reperfusion injury

The Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathway, a well-conserved and basic intracellular signaling cascade, is mostly inactivated under basal conditions, although it can be phosphorylated under extracellular stimulation; in addition, it can influence the transcription and expression of multiple genes involved in biological processes such as cellular growth, metabolism, differentiation, degradation and angiogenesis. The inflammatory response, apoptosis, oxidative stress and angiogenesis are the main factors involved in the pathogenesis of ischemic stroke. Numerous studies have confirmed that the JAK2/STAT3 axis can be activated rapidly by ischemic stress, which is closely related to the regulation of these important pathological processes. However, different opinions on the specific role of this signaling pathway remain. In this paper, we review and summarize previous studies on the JAK2/STAT3 pathway in ischemic stroke.

Paeoniflorin protects PC12 cells from oxygen-glucose deprivation/reoxygenation-induced injury via activating JAK2/STAT3 signaling

Ischemic stroke is the most common type of stroke, and it has become a major health issue as it is characterized by high mortality and morbidity rates. Paeoniflorin (PF) is a natural compound and the main active ingredient of Radix Paeoniae. The aim of the present study was to investigate the role of PF in oxygen-glucose deprivation/reoxygenation (OGD/R)-induced injury of PC12 cells and its association with the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway. An in vitro model of OGD/R injury was established in PC12 cells. Subsequently, Cell Counting Kit-8 assay and ELISA were used to evaluate cell viability and the secretion of inflammatory factors, respectively, in PC12 cells subjected to OGD/R and treated with PF. The levels of oxidative stress indicators and inflammatory factors were measured using corresponding commercial kits. In addition, the apoptosis rate of PC12 cells subjected to OGD/R and treated with PF was determined by flow cytometry, and the expression of apoptosis-related proteins was analyzed by western blotting. Additionally, the expression levels of JAK2/STAT3 pathway-related proteins were also evaluated. The cell viability, levels of oxidative stress, inflammation and apoptosis were also measured in OGD/R-induced PC12 cell injury models following co-treatment of cells with PF and FLLL32, a specific inhibitor of JAK2/STAT3 signaling. Cell viability was reduced, while oxidative stress and inflammation were increased after OGD/R-induced injury. However, the treatment of cells with PF significantly enhanced cell viability, and alleviated oxidative stress, inflammation and apoptosis of OGD/R-treated PC12 cells. Furthermore, PF activated the JAK2/STAT3 signaling pathway. Following FLLL32 intervention, the effects of PF on oxidative stress, inflammation and apoptosis of OGD/R-treated PC12 cells were reversed. In conclusion, the findings of the present study suggested that PF may protect PC12 cells from OGD/R-induced injury via activating the JAK2/STAT3 signaling pathway, thus providing novel insight into the mechanism through which PF may alleviate ischemic stroke and indicating a potential strategy for ischemic stroke treatment.

Interleukin-22 Plays a Protective Role by Regulating the JAK2-STAT3 Pathway to Improve Inflammation, Oxidative Stress, and Neuronal Apoptosis following Cerebral Ischemia-Reperfusion Injury

The interleukins (ILs) are a pluripotent cytokine family that have been reported to regulate ischemic stroke and cerebral ischemia/reperfusion (I/R) injury. IL-22 is a member of the IL-10 superfamily and plays important roles in tissue injury and repair. However, the effects of IL-22 on ischemic stroke and cerebral I/R injury remain unclear. In the current study, we provided direct evidence that IL-22 treatment decreased infarct size, neurological deficits, and brain water content in mice subjected to cerebral I/R injury. IL-22 treatment remarkably reduced the expression of inflammatory cytokines, including IL-1β, monocyte chemotactic protein- (MCP-) 1, and tumor necrosis factor- (TNF-) α, both in serum and the ischemic cerebral cortex. In addition, IL-22 treatment also decreased oxidative stress and neuronal apoptosis in mice after cerebral I/R injury. Moreover, IL-22 treatment significantly increased Janus tyrosine kinase (JAK) 2 and signal transducer and activator of transcription (STAT) 3 phosphorylation levels in mice and PC12 cells, and STAT3 knockdown abolished the IL-22-mediated neuroprotective function. These findings suggest that IL-22 might be exploited as a potential therapeutic agent for ischemic stroke and cerebral I/R injury.

Reassignment of crispatene, isolation and chemical characterization of stachydrine, isolated from the marine mollusk Elysia crispata

The molluscan genus Elysia Risso, 1818 (Sacoglossa) is composed of shell-less herbivore sea slugs. From these marine organisms, polyketides such as polypropynates have been isolated and showed cytotoxic, antibiotic, and antifungal, and antiviral properties. In this work, we reported the isolation, and structure elucidation of two compounds isolated from marine mollusk E. crispata. Both compounds isolated, crispatene (1) and stachydrine (2), were purified by HPLC. The chemical structure of compound (1) was reassigned through 1D and 2D NMR experiments and high-resolution electrospray ionization mass spectrometry (HRESIMS). On the other hand, this is the first time that compound (2) has been found in this species of mollusk or the marine environment, previously, (2) has only been found in terrestrial plants or bacteria in symbiosis with plants.

Engineered Multifunctional Nano- and Biological Materials for Cancer Immunotherapy

Cancer immunotherapy is set to emerge as the future of cancer therapy. However, recent immunotherapy trials in different cancers have yielded sub-optimal results, with durable responses seen in only a small fraction of patients. Engineered multifunctional nanomaterials and biological materials are versatile platforms that can elicit strong immune responses and improve anti-cancer efficacy when applied to cancer immunotherapy. While there are traditional systems such as polymer- and lipid-based nanoparticles, there is a wide variety of other materials with inherent and additive properties that can allow for more potent activation of the immune system. By synthesizing and applying multifunctional strategies, it allows for a more extensive and more effective repertoire of tools to use in the wide variety of situations that cancer presents itself. Here, several types of nanoscale and biological material strategies and platforms that provide their inherent benefits for targeting and activating multiple aspects of the immune system are discussed. Overall, this review aims to provide a comprehensive understanding of recent advances in the field of multifunctional cancer immunotherapy and trends that pave the way for more diverse and tactical regression of tumors through soliciting responses by either the adaptive or innate immune system, and even both simultaneously.

TLR4 /NF-ĸB and JAK2/STAT3 signaling pathways: Cellular signaling pathways targeted by cell-conditioned medium therapy in protection against ischemic stroke

Human amniotic membrane-derived mesenchymal stem cell-conditioned medium (hAMSC-CM) has been known to improve neuronal survival following ischemic stroke. The present study was designed to examine whether protective effects of hAMSC-CM against stroke can be linked to reducing neuroinflamation by targeting TLR4 /NF-ĸB and Jak2/Stat3 signaling pathways. Immunohistochemistry of hippocampus and western blot assay were performed to evaluate the expression of TLR4 /NF-ĸB and Jak2/Stat3, respectively. Real-time PCR assay was applied to investigate the mRNA levels of Jak2/Stat3. Hematoxylin and eosin (H&E) staining was used to investigate tissue damage and morphological changes in the CA1 region of hippocampus. Increased brain edema was seen in middle cerebral artery occlusion (MCAO) rats compared to sham. Post-treatment with hAMSC-CM markedly reduced brain edema in comparison with MCAO group (P < 0.05). Compared to sham, significantly increased levels of TLR4 /NF-ĸB and Jak2/Stat3 were seen in MCAO rats. Intravenous injection of hAMSC-CM after reperfusion markedly reduced levels of TLR4 /NF-ĸB and Jak2/Stat3 in hippocampus region (P < 0.05). Tissue damage and neuronal cell increased in the CA1 region of hippocampus that reversed by post-treatment by hAMSC-CM. Interestingly, our finding showed that hAMSC-CM can be considered as good candidate to reduce injury following ischemic stroke by decreasing activity of TLR4 /NF-ĸB and Jak2/Stat3 signaling pathways.

Organic Cation Transporter (OCT/OCTN) Expression at Brain Barrier Sites: Focus on CNS Drug Delivery

Therapeutic delivery to the central nervous system (CNS) continues to be a considerable challenge in the pharmacological treatment and management of neurological disorders. This is primarily due to the physiological and biochemical characteristics of brain barrier sites (i.e., blood-brain barrier (BBB), blood-cerebrospinal fluid barrier (BCSFB)). Drug uptake into brain tissue is highly restricted by expression of tight junction protein complexes and adherens junctions between brain microvascular endothelial cells and choroid plexus epithelial cells. Additionally, efflux transport proteins expressed at the plasma membrane of these same endothelial and epithelial cells act to limit CNS concentrations of centrally acting drugs. In contrast, facilitated diffusion via transporter proteins allows for substrate-specific flux of molecules across the plasma membrane, directing drug uptake into the CNS. Organic Cation Transporters (OCTs) and Novel Organic Cation Transporters (OCTNs) are two subfamilies of the solute carrier 22 (SLC22) family of proteins that have significant potential to mediate delivery of positively charged, zwitterionic, and uncharged therapeutics. While expression of these transporters has been well characterized in peripheral tissues, the functional expression of OCT and OCTN transporters at CNS barrier sites and their role in delivery of therapeutic drugs to molecular targets in the brain require more detailed analysis. In this chapter, we will review current knowledge on localization, function, and regulation of OCT and OCTN isoforms at the BBB and BCSFB with a particular emphasis on how these transporters can be utilized for CNS delivery of therapeutic agents.

Mechanism of delayed encephalopathy after acute carbon monoxide poisoning

Many hypotheses exist regarding the mechanism underlying delayed encephalopathy after acute carbon monoxide poisoning (DEACMP), including the inflammation and immune-mediated damage hypothesis and the cellular apoptosis and direct neuronal toxicity hypothesis; however, no existing hypothesis provides a satisfactory explanation for the complex clinical processes observed in DEACMP. Leucine-rich repeat and immunoglobulin-like domain-containing protein-1 (LINGO-1) activates the Ras homolog gene family member A (RhoA)/Rho-associated coiled-coil containing protein kinase 2 (ROCK2) signaling pathway, which negatively regulates oligodendrocyte myelination, axonal growth, and neuronal survival, causing myelin damage and participating in the pathophysiological processes associated with many central nervous system diseases. However, whether LINGO-1 is involved in DEACMP remains unclear. A DEACMP model was established in rats by allowing them to inhale 1000 ppm carbon monoxide gas for 40 minutes, followed by 3000 ppm carbon monoxide gas for an additional 20 minutes. The results showed that compared with control rats, DEACMP rats showed significantly increased water maze latency and increased protein and mRNA expression levels of LINGO-1, RhoA, and ROCK2 in the brain. Compared with normal rats, significant increases in injured neurons in the hippocampus and myelin sheath damage in the lateral geniculate body were observed in DEACMP rats. From days 1 to 21 after DEACMP, the intraperitoneal injection of retinoic acid (10 mg/kg), which can inhibit LINGO-1 expression, was able to improve the above changes observed in the DEACMP model. Therefore, the overexpression of LINGO-1 appeared to increase following carbon monoxide poisoning, activating the RhoA/ROCK2 signaling pathway, which may be an important pathophysiological mechanism underlying DEACMP. This study was reviewed and approved by the Medical Ethics Committee of Xiangya Hospital of Central South Hospital (approval No. 201612684) on December 26, 2016.