The attenuation of lung ischemia reperfusion injury by oxymatrine

Neuroprotective Effects of Oxymatrine via Triggering Autophagy and Inhibiting Apoptosis Following Spinal Cord Injury in Rats

Spinal cord injury (SCI) is a devastating neurological disorder characterized by high morbidity and disability. However, there is still a lack of effective treatments for it. The identification of drugs that promote autophagy and inhibit apoptosis in neurons is critical for improving patient outcomes following SCI. Previous studies have shown that increasing the activity of silent information regulator 1 (SIRT1) and downstream protein AMP-activated protein kinase (AMPK) in rat models of SCI is highly neuroprotective. Oxymatrine (OMT), a quinolizidine alkaloid, has exhibited neuroprotective effects in various central nervous system (CNS) diseases. However, its explicit effect and molecular mechanism in SCI are still unclear. Herein, we aimed to investigate the therapeutic effects of OMT and explore the potential role of autophagy regulation following SCI in rats. A modified compressive device (weight 35 g, time 5 min) was applied to induce moderate SCI in all groups except the sham group. After treatment with drugs or vehicle (saline), our results indicated that OMT treatment significantly reduced the lesion size, promoted survival of motor neurons, and subsequently attenuated motor dysfunction following SCI in rats. OMT significantly enhanced autophagy activity, inhibited apoptosis in neurons, and increased SIRT1 and p-AMPK expression levels. Interestingly, these effects of OMT on SCI were partially prevented by co-treatment with SIRT1 inhibitor EX527. Furthermore, combining OMT with the potent autophagy inhibitor chloroquine (CQ) could effectively abolish its promotion of autophagic flux. Taken together, these data revealed that OMT exerts a neuroprotective role in functional recovery against SCI in rats, and these effects are potentially associated with OMT-induced activation of autophagy via the SIRT1/AMPK signaling pathway.

Oxymatrine provides protection against Coxsackievirus B3-induced myocarditis in BALB/c mice

Oxymatrine is the primary pharmacological component of Sophora flavescens Ait. In the present study, we investigated the protective effect of oxymatrine against Coxsackievirus B3-induced myocarditis in mice. Coxsackievirus B3-infected HeLa cells were treated with oxymatrine and the viral titer, as well as the degree of cellular proliferation were determined. Additionally, BALB/c mice were infected with Coxsackievirus B3 and received differing concentrations of oxymatrine. On days 5 and 12 following treatment, mice were sacrificed, and serum lactate dehydrogenase, creatine kinase-MB isozyme, and tumor necrosis factor-α levels were quantified. The heart index and degree of myocardial tissue inflammation were also assessed. On day 5, the Coxsackievirus B3 TCID50 values of the heart tissue, and the expression of NTR, IFN-γ, and TNF-α genes in the myocardial tissue were measured. Our results showed that oxymatrine exhibits potent antiviral effects on Coxsackievirus B3 as 50% inhibition was achieved at a concentration as low as 0.238 mg/mL. Oxymatrine markedly reduced the viral titer and inhibited cardiac myocyte pathology exhibited in viral myocarditis. Furthermore, oxymatrine treatment reduced the expression of Coxsackievirus B3 NTR and mouse TNF-α genes compared to the controls. Therefore, our findings indicate that oxymatrine is a promising potent antiviral agent against Coxsackievirus B3-induced myocarditis.

Resolvin D1 Alleviates the Lung Ischemia Reperfusion Injury via Complement, Immunoglobulin, TLR4, and Inflammatory Factors in Rats

Lung ischemia-reperfusion injury (LIRI) is still an unsolved medical issue, which negatively affects the prognosis of many lung diseases. The aim of this study is to determine the effects of RvD1 on LIRI and the potential mechanisms involved. The results revealed that the levels of complement, immunoglobulin, cytokines, sICAM-1, MPO, MDA, CINC-1, MCP-1, ANXA-1, TLR4, NF-κBp65, apoptosis index, and pulmonary permeability index were increased, whereas the levels of SOD, GSH-PX activity, and oxygenation index were decreased in rats with LIRI. Except for ANXA-1, these responses induced by LIRI were significantly inhibited by RvD1 treatment. In addition, LIRI-induced structure damages of lung tissues were also alleviated by RvD1 as shown by H&E staining and transmission electron microscopy. The results suggest that RvD1 may play an important role in protection of LIRI via inhibition of complement, immunoglobulin, and neutrophil activation; down-regulation of TLR4/NF-κB; and the expression of a variety of inflammatory factors.

Effects and mechanisms of compound Chinese medicine and major ingredients on microcirculatory dysfunction and organ injury induced by ischemia/reperfusion

Microcirculation dysfunction and organ injury after ischemia and reperfusion (I/R) result from a complex pathologic process consisting of multiple links, with metabolism impairment in the ischemia phase and oxidative stress in the reperfusion phase as initiators, and any treatment targeting a single link is insufficient to cope with this. Compound Chinese medicine (CCM) has been applied in clinics in China and some Asian nations for >2000years. Studies over the past decades revealed the protective and therapeutic effect of CCMs and major ingredients on I/R-induced microcirculatory dysfunction and tissue injury in the heart, brain, liver, intestine, and so on. CCM contains diverse bioactive components with potential for energy metabolism regulation; antioxidant effect; inhibiting inflammatory cytokines release; adhesion molecule expression in leukocyte, platelet, and vascular endothelial cells; and the protection of thrombosis, albumin leakage, and mast cell degranulation. This review covers the major works with respect to the effects and underlying mechanisms of CCM and its ingredients on microcirculatory dysfunction and organ injury after I/R, providing novel ideas for dealing with this threat.

Potential Signaling Pathways Involved in the Clinical Application of Oxymatrine

Oxymatrine, an alkaloid component extracted from the roots of Sophora species, has been shown to have antiinflammatory, antifibrosis, and antitumor effects and the ability to protect against myocardial damage, etc. The potential signaling pathways involved in the clinical application of oxymatrine might include the TGF-β/Smad, toll-like receptor 4/nuclear factor kappa-light-chain-enhancer of activated B cells, toll-like receptor9/TRAF6, Janus kinase/signal transduction and activator of transcription, phosphatidylinositol-3 kinase/Akt, delta-opioid receptor-arrestinl-Bcl-2, CD40, epidermal growth factor receptor, nuclear factor erythroid-2-related factor 2/heme oxygenase-1 signaling pathways, and dimethylarginine dimethylaminohydrolase/asymmetric dimethylarginine metabolism pathway. In this review, we summarize the recent investigations of the signaling pathways related to oxymatrine to provide clues and references for further studies on its clinical application. Copyright © 2016 John Wiley & Sons, Ltd.

Inflammatory response and pneumocyte apoptosis during lung ischemia-reperfusion injury in an experimental pulmonary thromboembolism model

Lung ischemia-reperfusion injury (LIRI) may occur in the region of the affected lung after reperfusion therapy. The inflammatory response mechanisms related to LIRI in pulmonary thromboembolism (PTE), especially in chronic PTE, need to be studied further. In a PTE model, inflammatory response and apoptosis may occur during LIRI and nitric oxide (NO) inhalation may alleviate the inflammatory response and apoptosis of pneumocytes during LIRI. A PTE canine model was established through blood clot embolism to the right lower lobar pulmonary artery. Two weeks later, we performed embolectomy with reperfusion to examine the LIRI changes among different groups. In particular, the ratio of arterial oxygen partial pressure to fractional inspired oxygen (PaO2/FiO2), serum concentrations of tumor necrosis factor-α (TNF-α), myeloperoxidase concentrations in lung homogenates, alveolar polymorphonuclear neutrophils (PMNs), lobar lung wet to dry ratio (W/D ratio), apoptotic pneumocytes, and lung sample ultrastructure were assessed. The PaO2/FiO2 in the NO inhalation group increased significantly when compared with the reperfusion group 4 and 6 h after reperfusion (368.83 ± 55.29 vs. 287.90 ± 54.84 mmHg, P < 0.05 and 380.63 ± 56.83 vs. 292.83 ± 6 0.34 mmHg, P < 0.05, respectively). In the NO inhalation group, TNF-α concentrations and alveolar PMN infiltration were significantly decreased as compared with those of the reperfusion group, 6 h after reperfusion (7.28 ± 1.49 vs. 8.90 ± 1.43 pg/mL, P < 0.05 and [(19 ± 6)/10 high power field (HPF) vs. (31 ± 11)/10 HPF, P < 0.05, respectively]. The amount of apoptotic pneumocytes in the lower lobar lung was negatively correlated with the arterial blood PaO2/FiO2, presented a positive correlation trend with the W/D ratio of the lower lobar lung, and a positive correlation with alveolar PMN in the reperfusion group and NO inhalation group. NO provided at 20 ppm for 6 h significantly alleviated LIRI in the PTE model. Our data indicate that, during LIRI, an obvious inflammatory response and apoptosis occur in our PTE model and NO inhalation may be useful in treating LIRI by alleviating the inflammatory response and pneumocyte apoptosis. This potential application warrants further investigation.

Resolvin D1 mitigates energy metabolism disorder after ischemia-reperfusion of the rat lung

BACKGROUND

Energy metabolism disorder is a critical process in lung ischemia-reperfusion injury (LIRI). This study was aimed to determine the effects of resolvin D1 (RvD1) on the energy metabolism in LIRI.

METHODS

Forty Sprague-Dawley rats were divided into the following groups: Sham group; untreated ischemia-reperfusion (IR) control; IR treated with normal saline (IR-NS); and IR treated with RvD1 (IR-RV) (100 μg/kg, iv). LIRI and energy metabolism disorder were determined in these rats.

RESULTS

The results revealed that the levels of interleukin (IL)-1β, tumor necrosis factor-α, IL-10, monocyte chemoattractant protein-1, macrophage inflammatory protein-2, cytokine-induced neutrophil chemoattractant-1, injured alveoli rate, apoptosis index, pulmonary permeability index, malondialdehyde, ADP, and lactic acid were increased, whereas the levels of ATP, ATP/ADP, glycogen, Na(+)-K(+)-ATPase, superoxide dismutase, glutathione peroxidase activity, pulmonary surfactant associated protein-A, and oxygenation index were decreased in rats with LIRI. Except for IL-10, all these biomarkers of LIRI and its related energy metabolism disorder were significantly inhibited by RvD1 treatment. In addition, histological analysis via hematoxylin-eosin staining, and transmission electron microscopy confirmed that IR-induced structure damages of lung tissues were reduced by RvD1.

CONCLUSION

RvD1 improves the energy metabolism of LIRI disturbance, protects the mitochondrial structure and function, increases the ATP, glycogen content and Na(+)-K(+)-ATPase activity of lung tissue, balances the ratio of ATP/ADP and finally decreases the rate of apoptosis, resulting in the protection of IR-induced lung injury. The improved energy metabolism after LIRI may be related to the reduced inflammatory response, the balance of the oxidative/antioxidant and the pro-inflammatory/anti-inflammatory systems in rats.

Oxymatrine ameliorates renal ischemia-reperfusion injury from oxidative stress through Nrf2/HO-1 pathway

PURPOSE

To investigate if oxymatrine pretreatment could ameliorate renal I/R injury induced in rats and explore the possible role of oxymatrine in Nrf2/HO-1 pathway.

METHODS

Unilaterally nephrectomized rats were insulted by I/R in their left kidney. Twenty four rats were randomly divided into three groups: sham group, I/R + saline-treated group, I/R + OMT-treated group. Oxymatrine or vehicle solution was administered intraperitoneally injected 60 min before renal ischemia, respectively. Renal function, histology, makers of oxidative stress, cell apoptosis and Nrf2/HO-1 expressions were assessed.

RESULTS

Oxymatrine pretreatment exhibited an improved renal functional recovery, alleviated histological injury and oxidative stress, inhibiting tubular apoptosis, and accompanied by upregulated the expression of Nrf2/HO-1 proteins.

CONCLUSION

Oxymatrine may attenuate renal ischemia/reperfusion injury, and this renoprotective effect may be through activating the Nrf2/HO-1 pathway.

Oxymatrine and cancer therapy

Oxymatrine is a kind of alkaloid extracted from traditional Chinese herb Sophora flavescens Ait. It has been proved to exert various biological activities such as anti-angiogenesis, proliferation-inhibiting, apoptosis-promoting, analgesic-strengthening, and anti-metastasis. The biological activities are related with inhibition of angiogenesis-associated factors, regulation of related signaling pathway and protein expression, synergistic effects with chemotherapy drug, cell cycle arrest and inhibition of voltage-activated K+ channel. In this review, we summarize the recent investigations of oxymatrine in cancer therapy so as to provide references for further study and clinical therapy.