Therapeutic Targets for Regulating Oxidative Damage Induced by Ischemia-Reperfusion Injury: A Study from a Pharmacological Perspective

Effect of fullerenol C60 on lung and renal tissue in lower extremity ischemia‑reperfusion injury in sevoflurane‑treated rats

The aim of the present study was to examine the effect of fullerenol C60 on lung and kidney tissue in sevoflurane‑treated rats with lower extremity ischemia‑reperfusion (IR) injury. A total of 30 Wistar albino rats weighing 225‑275 g were used and were equally divided into five groups (n=6/group): i) Sham; ii) IR; iii) IR‑fullerenol C60 (IR‑FUL); iv) IR‑sevoflurane; and v) IR‑fullerenol C60‑sevoflurane (IR‑FUL‑SEVO). Fullerenol C60 was administered intraperitoneally prior to lower extremity IR induction and sevoflurane was administered during the IR injury. Subsequently, lung and kidney histopathological examinations, and serum biochemical analyses were performed. Lung tissue showed markedly increased congestion and neutrophil infiltration in the IR group compared with in the sham group, and notable decreases in congestion and neutrophil infiltration were observed in the treatment groups compared with in the IR group. In the histopathological evaluation of the kidney samples, vacuolization, loss of brush border in tubular epithelial cells, tubular epithelial loss and varying degrees of tubular damage were observed in all groups that underwent IR. There was a significant increase in the mean renal tubule injury score in all IR groups compared with that in the sham group. In addition, the mean kidney injury score was significantly lower in the IR‑FUL and IR‑FUL‑SEVO groups than that in the IR group. It was observed that the expression levels of tumor necrosis factor‑α, interleukin 1β and intercellular adhesion molecule 1 in the lung and kidney tissues were increased following IR, and were decreased in the groups treated with fullerenol C60 and sevoflurane. Notably, it was determined that the reduction in cytokine expression was greatest in the IR‑FUL group. When the oxidant status parameters in the lungs and kidneys were examined, thiobarbituric acid reactive substances levels, and catalase and glutathione S‑transferase enzyme activities were significantly different in the groups receiving sevoflurane or fullerenol C60 treatment compared with those in the IR group. The present study demonstrated the protective effects of fullerenol C60 on the lung and kidney tissues of rats under sevoflurane anesthesia after establishment of lower extremity IR. The results of the present study showed that fullerenol C60 can reduce oxidative and histopathological damage in the lungs and kidneys following IR of the lower extremities.

Autologous mitochondrial transplantation in male mice as a strategy to prevent deleterious effects of peripheral ischemia-reperfusion

Ischemia-reperfusion (IR) is known to induce severe tissue damage, notably through mitochondrial dysfunction. Mitochondrial transplantation has emerged as a promising therapeutic strategy in cardiac IR; however, few studies have previously assessed its efficacy in the context of peripheral IR. Therefore, the objective of this study was to assess the effect of mitochondrial transplantation in a hindlimb model of IR injury. Thirty-six SWISS mice were divided into three groups: control (CTL, n = 12), ischemia-reperfusion (IR, n = 12), and IR with mitochondrial transplantation (MT, n = 12). Ischemia (2 h) was induced using the tourniquet model around the right hind limb in the IR and MT groups. In MT group, mitochondria isolated from the right rectus muscle, a nonischemic region, were injected shortly before reperfusion. Mitochondrial respiration, calcium retention capacity, and Western blotting analysis were performed 2 h after reperfusion. Compared with the CTL group, IR led to a decrease in the mitochondrial respiratory capacity, particularly for the basal state (-30%; P = 0.015), oxidative phosphorylation (-36%; P = 0.024), and calcium retention capacity (-45%; P = 0.007). Interestingly, mitochondrial transplantation partially restored these functions since no differences between MT and CTL groups were found. In addition, the administration of healthy mitochondria resulted in a positive regulation of redox balance and mitochondrial dynamics within the skeletal muscle. Although further investigations are needed to better characterize underlying mechanisms, mitochondrial transplantation represents a promising strategy in the setting of IR-induced muscular damage.NEW & NOTEWORTHY Ischemia-reperfusion injury leads to severe muscular damage. Even if prompt revascularization is the treatment of choice, muscular alterations can lead to severe sequalae as mitochondrial dysfunction. Accordingly, adjunctive strategies are needed to overcome the muscular damage. Mitochondrial transplantation has shown beneficial effects in cardiac ischemia-reperfusion, but its role in peripheral muscle is not well established. In this study, we found that mitochondrial transplantation partially restored muscular function when submitted to ischemia reperfusion.

Advance in topical biomaterials and mechanisms for the intervention of pressure injury

Pressure injuries (PIs) are localized tissue damage resulting from prolonged compression or shear forces on the skin or underlying tissue, or both. Different stages of PIs share common features include intense oxidative stress, abnormal inflammatory response, cell death, and subdued tissue remodeling. Despite various clinical interventions, stage 1 or stage 2 PIs are hard to monitor for the changes of skin or identify from other disease, whereas stage 3 or stage 4 PIs are challenging to heal, painful, expensive to manage, and have a negative impact on quality of life. Here, we review the underlying pathogenesis and the current advances of biochemicals in PIs. We first discuss the crucial events involved in the pathogenesis of PIs and key biochemical pathways lead to wound delay. Then, we examine the recent progress of biomaterials-assisted wound prevention and healing and their prospects.

Mitochondrial dysfunctions induce PANoptosis and ferroptosis in cerebral ischemia/reperfusion injury: from pathology to therapeutic potential

Ischemic stroke (IS) accounts for more than 80% of the total stroke, which represents the leading cause of mortality and disability worldwide. Cerebral ischemia/reperfusion injury (CI/RI) is a cascade of pathophysiological events following the restoration of blood flow and reoxygenation, which not only directly damages brain tissue, but also enhances a series of pathological signaling cascades, contributing to inflammation, further aggravate the damage of brain tissue. Paradoxically, there are still no effective methods to prevent CI/RI, since the detailed underlying mechanisms remain vague. Mitochondrial dysfunctions, which are characterized by mitochondrial oxidative stress, Ca²⁺ overload, iron dyshomeostasis, mitochondrial DNA (mtDNA) defects and mitochondrial quality control (MQC) disruption, are closely relevant to the pathological process of CI/RI. There is increasing evidence that mitochondrial dysfunctions play vital roles in the regulation of programmed cell deaths (PCDs) such as ferroptosis and PANoptosis, a newly proposed conception of cell deaths characterized by a unique form of innate immune inflammatory cell death that regulated by multifaceted PANoptosome complexes. In the present review, we highlight the mechanisms underlying mitochondrial dysfunctions and how this key event contributes to inflammatory response as well as cell death modes during CI/RI. Neuroprotective agents targeting mitochondrial dysfunctions may serve as a promising treatment strategy to alleviate serious secondary brain injuries. A comprehensive insight into mitochondrial dysfunctions-mediated PCDs can help provide more effective strategies to guide therapies of CI/RI in IS.

Vitamin D Receptor Regulates Autophagy to Inhibit Apoptosis and Promote Proliferation in Hepatocyte Injury

BACKGROUND

Oxidative stress is an important mechanism in liver ischemia/reperfusion (I/R) injury. Hepatocyte apoptosis and proliferation occur in parallel with liver I/R injury, and the degree of apoptosis and proliferation determines the effects on hepatocytes. Vitamin D receptor (VDR) can lessen liver I/R injury, but previous studies focused mostly on inflammation and immunity.

METHODS

H₂O₂ was used to induce hepatocyte injury. Before treatment with H₂O₂, Hep-3B cells were pretreated with paricalcitol (PC) and siRNA-VDR. Rapamycin and chloroquine were also applied in the study.

RESULTS

The number of apoptotic cells was measured with an annexin V (AV) -fluorescein isothiocyanate apoptosis detection kit. Expression of proteins was measured by western blotting. As compared with the H₂O₂+Hep-3B group, levels of AV/PI, cleaved caspase-3, and p62 were lower, and expression levels of Bcl-2, proliferating cell nuclear antigen, and VDR were higher, in the PC+H₂O₂+Hep-3B group. When the VDR gene was silenced by siRNA-VDR in the siRNA-VDR+H₂O₂+Hep-3B group, expressions of AV/PI, cleaved caspase-3, and p62 were upregulated, and expressions of Bcl-2, proliferating cell nuclear antigen, and VDR were downregulated, as compared with values for the siRNA-NC+H₂O₂+Hep-3B group. Treatment with rapamycin or chloroquine partially reversed the effect of PC and siRNA-VDR on apoptosis and proliferation.

CONCLUSIONS

VDR mediates hepatocyte apoptosis and proliferation through autophagy.

Asiaticoside attenuates oxygen-glucose deprivation/reoxygenation-caused injury of cardiomyocytes by inhibiting autophagy

Asiaticoside is a natural triterpene compound derived from Centella asiatica, possessing confirmed cardioprotective property. However, the roles of asiaticoside in regulating oxygen-glucose deprivation/reoxygenation (OGD/R)-caused cardiomyocyte dysfunction remain largely obscure. Human cardiomyocyte AC16 cells were stimulated with OGD/R to mimic myocardial ischemia/reperfusion injury and treated with asiaticoside. Cytotoxicity was investigated by CCK-8 assay and lactate dehydrogenase (LDH) release analysis. Autophagy- and Wnt/β-catenin signaling-related protein levels were measured via western blotting. Asiaticoside (0-20 μM) did not induce cardiomyocyte cytotoxicity. Asiaticoside (20 μM) mitigated OGD/R-induced autophagy, cytotoxicity, oxidative stress, and myocardial injury. Rapamycin, an autophagy inductor, reversed the influences of asiaticoside on autophagy, cytotoxicity, oxidative stress, and myocardial injury, whereas 3-methyadanine, an autophagy inhibitor, played an opposite effect. Asiaticoside (20 μM) attenuated OGD/R-induced Wnt/β-catenin signaling inactivation, which was reversed after transfection with si-β-catenin. Transfection with si-β-catenin attenuated the influences of asiaticoside on autophagy, cytotoxicity, oxidative stress, and myocardial injury. In conclusion, asiaticoside protected against OGD/R-induced cardiomyocyte cytotoxicity, oxidative stress, and myocardial injury via blunting autophagy through activating the Wnt/β-catenin signaling, indicating the therapeutic potential of asiaticoside in myocardial ischemia/reperfusion injury.

The Therapeutic Roles of Cinnamaldehyde against Cardiovascular Diseases

Evidence from epidemiological studies has demonstrated that the incidence and mortality of cardiovascular diseases (CVDs) increase year by year, which pose a great threat on social economy and human health worldwide. Due to limited therapeutic benefits and associated adverse effects of current medications, there is an urgent need to uncover novel agents with favorable safety and efficacy. Cinnamaldehyde (CA) is a bioactive phytochemical isolated from the stem bark of Chinese herbal medicine Cinnamon and has been suggested to possess curative roles against the development of CVDs. This integrated review intends to summarize the physicochemical and pharmacokinetic features of CA and discuss the recent advances in underlying mechanisms and potential targets responsible for anti-CVD properties of CA. The CA-related cardiovascular protective mechanisms could be attributed to the inhibition of inflammation and oxidative stress, improvement of lipid and glucose metabolism, regulation of cell proliferation and apoptosis, suppression of cardiac fibrosis, and platelet aggregation and promotion of vasodilation and angiogenesis. Furthermore, CA is likely to inhibit CVD progression via affecting other possible processes including autophagy and ER stress regulation, gut microbiota and immune homeostasis, ion metabolism, ncRNA expression, and TRPA1 activation. Collectively, experiments reported previously highlight the therapeutic effects of CA and clinical trials are advocated to offer scientific basis for the compound future applied in clinical practice for CVD prophylaxis and treatment.