Galuteolin attenuates cerebral ischemia/reperfusion injury in rats via anti-apoptotic, anti-oxidant, and anti-inflammatory mechanisms

Apocynin inhibits compressive force-induced apoptosis and autophagy of periodontal ligament stem cells

OBJECTIVE

This study aimed to evaluate the effect of Apocynin on compressive force-induced apoptosis and autophagy in periodontal ligament stem cells (PDLSCs).

MATERIALS AND METHODS

Periodontal ligament stem cells were subjected to a uniform compressive force of 2.0 g/cm2 for 24 h, without and with addition of 50, 100 and 200 μM Apocynin. Beclin-1 was overexpressed in PDLSCs. Flow cytometry was used to assess apoptosis and transmission electron microscopy was used to evaluate ultrastructural features of PDLSCs. Immunofluorescence was used to assess the levels of microtubule-associated protein 1 light chain 3 (LC3). The protein levels of B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X (Bax), Caspase-3, LC3, and Beclin were determined by Western blot analysis.

RESULTS

Compressive force of PDLSCs significantly increased apoptosis, Bax, Caspase-3, the number of autophagosome or autolysosomes, Beclin-1, the ratio of LC3 II/LC3 I, and decreased Bcl-2. Apocynin was shown to inhibit apoptosis and Beclin-1-mediated autophagy. Over-expression of Beclin-1 increased apoptosis and autophagy.

CONCLUSIONS

Application of Apocynin attenuated long-term compressive force-induced apoptosis by regulating Beclin-1-mediated autophagy in PDLSCs. These results provide an alternative approach to improve orthodontic treatment outcomes for patients.

Ischemic stroke protected by ISO-1 inhibition of apoptosis via mitochondrial pathway

Macrophage migration inhibitory factor (MIF) is an immune mediator associated with inflammation, which is upregulated after ischemia in brain tissue. ISO-1 is a potent inhibitor of MIF tautomerase and can protect neurons by reducing the permeability of blood brain barrier (BBB). In this study, we investigated the role of ISO-1 in cerebral ischemia/reperfusion injury by establishing a model of middle cerebral artery occlusion/reperfusion in rats. Rats were randomly divided into four groups: the sham operation group, the ISO-1group, the cerebral I/R group, and the ISO-1 + I/R group. We assessed the degree of neurological deficit in each group and measured the volume of cerebral infarction. We detected the expression of MIF in the core necrotic area and penumbra. We detected the expression of apoptosis-related proteins, apoptosis-inducing factor (AIF), endonuclease G (EndoG) and cytochrome c oxidase-IV (COX-IV) in the ischemic penumbra region. The results showed that MIF was expressed in the ischemic penumbra, while the injection of ISO-1 was able to alleviate neurological damage and reduce the infarction volume. In the cerebral ischemic penumbra region, ISO-1 could reduce the expression of Bax and Caspase3 and inhibit the displacement of AIF and EndoG to the nucleus simultaneously. Besides, ISO-1 also exhibited the ability to reduce apoptosis. In summary, ISO-1 may inhibit neuronal apoptosis through the endogenous mitochondrial pathway and reduce the injury of brain I/R after ischemic stroke.

Jak2 Inhibitor AG490 Improved Poststroke Central and Peripheral Inflammation and Metabolic Abnormalities in a Rat Model of Ischemic Stroke

Poststroke hyperglycemia and inflammation have been implicated in the pathogenesis of stroke. Janus Kinase 2 (Jak2), a catalytic signaling component for cytokine receptors such as Interleukin-6 (IL-6), has inflammatory and metabolic properties. This study aimed to investigate the roles of Jak2 in poststroke inflammation and metabolic abnormality in a rat model of permanent cerebral ischemia. Pretreatment with Jak2 inhibitor AG490 ameliorated neurological deficit, brain infarction, edema, oxidative stress, inflammation, caspase-3 activation, and Zonula Occludens-1 (ZO-1) reduction. Moreover, in injured cortical tissues, Tumor Necrosis Factor-α, IL-1β, and IL-6 levels were reduced with concurrent decreased NF-κB p65 phosphorylation, Signal Transducers and Activators of Transcription 3 phosphorylation, Ubiquitin Protein Ligase E3 Component N-Recognin 1 expression, and Matrix Metalloproteinase activity. In the in vitro study on bEnd.3 endothelial cells, AG490 diminished IL-6-induced endothelial barrier disruption by decreasing ZO-1 decline. Metabolically, administration of AG490 lowered fasting glucose, with improvements in glucose intolerance, plasma-free fatty acids, and plasma C Reactive Proteins. In conclusion, AG490 improved the inflammation and oxidative stress of neuronal, hepatic, and muscle tissues of stroke rats as well as impairing insulin signaling in the liver and skeletal muscles. Therefore, Jak2 blockades may have benefits for combating poststroke central and peripheral inflammation, and metabolic abnormalities.

M, Siva Sankar Reddy L, Dastagiri Reddy Y, Somasekhar G, Sirisha N, Nagaraju K, Shouib M, Rizwaan A. A new cerebral ischemic injury model in rats, preventive effect of gallic acid and in silico approaches

Current study was designed multiple occlusions and reperfusion of bilateral carotid arteries induced cerebral injury model and evaluated the protective effect of gallic acid on it. In silico study was involved to study gallic acid binding affinity on cerebrotonic proteins compared with standard drugs using Autodoc vina tool. Cerebral ischemia was induced by occlusion of bilateral common carotid arteries for 10 mins followed by 10 reperfusions (1 cycle), cycle was continued to 3 cycles (MO/RCA), then pathological changes were observed by estimation of brain antioxidants as superoxide dismutase, glutathione, catalase, oxidants like malonaldehyde, cerebral infarction area, histopathology, and study gallic acid treatment against cerebral injury. Gallic acid exhibited a strong binding affinity on targeted cerebrotoxic proteins. MO/RCA rat brain antioxidant levels were significantly decreased and increased MDA levels (p < 0.0001), Infarction size compared to sham rats. Gallic acid treatment rat brain MDA levels significantly decreased (p < 0.4476) and increased SOD (p < 0.0001), CAT (p < 0.0001), GSH (p < 0.0001), cerebral infarction area when compared to MO/RCA group. Developed model showed significant cerebral ischemic injury in rats, injury was ameliorated by Gallic acid treatment and in silico approaches also inhibit the cerebrotoxic protein function by targeting on active sites.

Honeysuckle-derived microRNA2911 inhibits tumor growth by targeting TGF-β1

Background

Honeysuckle is a time‐honored herb with anticancer activity in traditional Chinese medicine. Recently, accumulating reports are suggesting that the microRNAs in this medicinal plant not only play a physiological role in their original system, but also can be transmitted to another species as potential therapeutic components. In the numerous bioactive investigations, the anti-tumor effects of these microRNAs in the magical herb are rarely studied, especially the special miR2911, a honeysuckle-encoded atypical microRNA, with high stability during the boiling process and unique biological activity to target TGF-β1 mRNA.

Methods

Luciferase assay was conducted to test the ability of miR2911 to target TGF-β1 mRNA. ELISA was performed to determine the expression level of TGF-β1 of mouse colorectal adenocarcinoma CT26 cells when treated with miR2911 and tumor tissue in Sidt1^+/+ and Sidt1^−/− mice. qRT-PCR was performed to examine the level of expression of miR2911. Tumor-bearing wild and nude mice were employed to evaluate the anti-tumor effect of honeysuckle and miR2911 in vivo. Tumor tissue necrosis was observed by H&E staining. Besides, the infiltration of T lymphocytes across solid tumors was tested by immunostaining staining.

Results

Our results showed that honeysuckle slowed the development of colon cancer down. Further research showed that miR2911 could bind strongly to TGF-β1 mRNA and down-regulate the expression of TGF-β1 and had a high stability under boiling and acid condition. Moreover, SIDT1 mediated dietary miR2911 inter-species absorption. And we found that miR2911 had a similar anticancer effect as honeysuckle. Mechanistically, miR2911 reversed the tumor-promoting effect of TGF-β1 by an increase of T lymphocytes infiltration, resulting in slowing the colon cancer process in immunocompetent mice. Consistent with this inference, the anti-tumor effect of miR2911 was revealed to be abolished in T cell immune deficiency mice.

Conclusion

Taken together, honeysuckle-derived miR2911 showed an anti-tumor effect in colon cancer through targeting TGF-β1 mRNA. The down-regulation of TGF-β1 promoted T lymphocytes infiltration, and accordingly impeded the colon tumor development.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-021-00453-y.

TNF-α Receptor Inhibitor Alleviates Metabolic and Inflammatory Changes in a Rat Model of Ischemic Stroke

Hyperglycemia and inflammation, with their augmented interplay, are involved in cases of stroke with poor outcomes. Interrupting this vicious cycle thus has the potential to prevent stroke disease progression. Tumor necrosis factor-α (TNF-α) is an emerging molecule, which has inflammatory and metabolic roles. Studies have shown that TNF-α receptor inhibitor R-7050 possesses neuroprotective, antihyperglycemic, and anti-inflammatory effects. Using a rat model of permanent cerebral ischemia, pretreatment with R-7050 offered protection against poststroke neurological deficits, brain infarction, edema, oxidative stress, and caspase 3 activation. In the injured cortical tissues, R-7050 reversed the activation of TNF receptor-I (TNFRI), NF-κB, and interleukin-6 (IL-6), as well as the reduction of zonula occludens-1 (ZO-1). In the in vitro study on bEnd.3 endothelial cells, R-7050 reduced the decline of ZO-1 levels after TNF-α-exposure. R-7050 also reduced the metabolic alterations occurring after ischemic stroke, such as hyperglycemia and increased plasma corticosterone, free fatty acids, C reactive protein, and fibroblast growth factor-15 concentrations. In the gastrocnemius muscles of rats with stroke, R-7050 improved activated TNFRI/NF-κB, oxidative stress, and IL-6 pathways, as well as impaired insulin signaling. Overall, our findings highlight a feasible way to combat stroke disease based on an anti-TNF therapy that involves anti-inflammatory and metabolic mechanisms.

Safranal protects against ischemia-induced PC12 cell injury through inhibiting oxidative stress and apoptosis

Safranal, isolated from saffron (Crocus sativus L.), is known to possesses neuroprotective effects. In this study, the neuroprotective potential of safranal against PC12 cell injury triggered by ischemia/reperfusion was investigated. PC12 cells were pretreated with safranal at concentration ranges of 10-160 μM for 2 h and then deprived from oxygen-glucose-serum for 6 h, followed by reoxygenation for 24 h (OGD condition). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), 2,7-dichlorofluorescin diacetate (DCF-DA), and comet assays were used to measure the extent of cellular viability, reactive oxygen substances (ROS), and DNA damage, respectively. Also, propidium iodide (PI) flow cytometry assay and western blotting of bax, bcl-2, and cleaved caspase-3 were performed for assessment of apoptosis. OGD exposure reduced the cell viability and increased intracellular ROS production, oxidative DNA damage, and apoptosis, in comparison with untreated control cells. Pretreatment with safranal (40 and 160 μM) significantly attenuated OGD-induced PC12 cell death, oxidative damage, and apoptosis. Furthermore, safranal markedly reduced the overexpression of bax/bcl-2 ratio and active caspase-3 following OGD (p < 0.05). The present findings indicated that safranal protects against OGD-induced neurotoxicity via modulating of oxidative and apoptotic responses.Graphical abstract The schematic representation of the mode of action of safranal against PC12 cells death induced by oxygen-glucose-serum deprivation and reoxygenation (OGD-R).

Galuteolin suppresses proliferation and inflammation in TNF-α-induced RA-FLS cells by activating HMOX1 to regulate IKKβ/NF-κB pathway

OBJECTIVE

Galuteolin (Galu) is a substance extracted and purified from honeysuckle. The purpose of this study was to explore the effects of Galu on the TNF-α-induced RA-FLS cells (synoviocytes) and reveal its potential molecular mechanism from the perspectives of anti-apoptosis and anti-inflammation.

METHODS

After TNF-α stimulation, cell proliferation of RA-FLS was assessed by CCK-8 assay. TUNEL staining was used to detect the apoptosis. Western blot was used to detect the expressions of Iκκβ, p-p65, p65, p-IκB, IκB, Cleaved-caspase3, Caspase-3, Bcl-2, and Bax. HO-1 were determined by RT-PCR. The contents of pro-inflammatory cytokines IL-1β, IL-6, IL-8, and MMP-1 were determined by ELISA.

RESULTS

Galu significantly suppressed cell proliferation in a dose-dependent manner. Additionally, Galu obviously promotes cell apoptosis rate of RA-FLS cells and elevated the expression levels of HO-1, caspase-3, and Bax, while reducing the expression level of Bcl-2. Furthermore, Galu apparently inhibited the levels of Iκκβ, p-p65, and p-IκB. Moreover, Galu also significantly reduced the levels of pro-inflammatory factors IL-1β, IL-6, IL-8, and MMP-1 in RA-FLS cells.

CONCLUSION

Galuteolin exerts protective effects against TNF-α-induced RA-FLS cells by inhibiting apoptosis and inflammation, which can guide the clinical use of rheumatoid arthritis.

CU06-1004 (endothelial dysfunction blocker) ameliorates astrocyte end-feet swelling by stabilizing endothelial cell junctions in cerebral ischemia/reperfusion injury

Cerebral ischemia, or stroke, is widespread leading cause of death and disability. Surgical and pharmacological interventions that recover blood flow are the most effective treatment strategies for stroke patients. However, restoring the blood supply is accompanied by severe reperfusion injury, with edema and astrocyte end-feet disruption. Here, we report that the oral administration of CU06-1004 (previously Sac-1004), immediately after onset of ischemia/reperfusion (I/R), ameliorated cerebral damage. CU06-1004 stabilized blood‑brain barrier by inhibiting the disruption of the tight junction-related protein zona occludens-1 and the cortical actin ring in endothelial cells (ECs) after I/R. Interestingly, CU06-1004 significantly suppressed astrocyte end-feet swelling following I/R, by reducing aquaporin 4 and connexin 43 levels, which mediates swelling. Furthermore, the degradation of β1-integrin and β-dystroglycan, which anchors to the cortical actin ring in ECs, was inhibited by CU06-1004 administration after I/R. Consistently, CU06-1004 administration following I/R also suppressed the loss of laminin and collagen type IV, which bind to the cortical actin ring anchoring proteins. Unlike the protective effects of CU06-1004 in ECs, astrocyte viability and proliferation were not directly affected. Taken together, our observations suggest that CU06-1004 inhibits I/R-induced cerebral edema and astrocyte end-feet swelling by maintaining EC junction stability. KEY MESSAGES: • CU06-1004 ameliorates I/R-induced cerebral injury. • EC junction integrity was stabilized by CU06-1004 treatment after I/R. • CU06-1004 reduces astrocyte end-feet swelling following I/R. • EC junction stability affects astrocyte end-feet structure maintenance after I/R.

Metabolomics Analysis of the Effect of Hydrogen-Rich Water on Myocardial Ischemia-Reperfusion Injury in Rats

To investigate the effect of hydrogen-rich water on myocardial tissue metabolism in a myocardial ischemia-reperfusion injury (MIRI) rat model. Twelve rats were randomly divided into a hydrogen-rich water group and a control group of size 6 each. After the heart was removed, it was fixed in the Langendorff device, and the heart was perfused with 37 °C perfusion solution pre-balanced with oxygen. The control group was perfused with Kreb's-Ringers (K-R) solution, and the hydrogen-rich water group was perfused with K-R solution + hydrogen-rich water. Liquid Chromatograph Mass Spectrometer (LC-MS) analysis platform was used for metabolomics research. Principle component analysis (PCA), partial least squares discriminant analysis (PLS-DA), orthogonal partial least squares discriminant analysis (OPLS-DA), Variable importance in projection (VIP) value of OPLS-DA model (threshold value ≥1) were employed with independent sample T Test (p < 0.05) to find differentially expressed metabolites, and screen for differential metabolic pathways. VIP (OPLS-DA) analysis was performed with T test, and the metabolites of the control group and the hydrogen-rich water group were significantly different, and the glycerophospholipid metabolism was screened. Seven myocardial ischemia-reperfusion injury (MIRI)-related signaling pathways were identified, including glycerophospholipid metabolism, glycosylphosphatidylinositol (GPI) anchored biosynthesis, and purine metabolism, as well as 10 biomarkers such as phosphatidylcholine, phosphatidylethanolamine and phosphatidylserine. Hydrogen-rich water regulates the metabolic imbalance that could change MIRI myocardial tissue metabolism, and alleviate ischemia-reperfusion injury in isolated hearts of rats through multiple signaling pathways.

RIPC provides neuroprotection against ischemic stroke by suppressing apoptosis via the mitochondrial pathway

Ischemic stroke is a common disease with high morbidity and mortality. Remote ischemic preconditioning (RIPC) can stimulate endogenous protection mechanisms by inducing ischemic tolerance to reduce subsequent damage caused by severe or fatal ischemia to non-ischemic organs. This study was designed to assess the therapeutic properties of RIPC in ischemic stroke and to elucidate their underlying mechanisms. Neurobehavioral function was evaluated with the modified neurological severity score (mNSS) test and gait analysis. PET/CT was used to detect the ischemic volume and level of glucose metabolism. The protein levels of cytochrome c oxidase-IV (COX-IV) and heat shock protein 60 (HSP60) were tested by Western blotting. TUNEL and immunofluorescence staining were used to analyze apoptosis and to observe the nuclear translocation and colocalization of apoptosis-inducing factor (AIF) and endonuclease G (EndoG) in apoptotic cells. Transmission electron microscopy (TEM) was used to detect mitochondrial-derived vesicle (MDV) production and to assess mitochondrial ultrastructure. The experimental results showed that RIPC exerted significant neuroprotective effects, as indicated by improvements in neurological dysfunction, reductions in ischemic volume, increases in glucose metabolism, inhibition of apoptosis, decreased nuclear translocation of AIF and EndoG from mitochondria and improved MDV formation. In conclusion, RIPC alleviates ischemia/reperfusion injury after ischemic stroke by inhibiting apoptosis via the endogenous mitochondrial pathway.