Naringin protects viscera from ischemia/reperfusion injury by regulating the nitric oxide level in a rat model

Naringin ameliorates 5-fluorouracil induced cardiotoxicity: An insight into its modulatory impact on oxidative stress, inflammatory and apoptotic parameters

5-fluorouracil (5-FU) is an efficacious fluoropyrimidine antimetabolite anticancer drug, however, its clinical utility is constrained due to side effect toxicity on delicate organs, including the heart. This study thus aimed at exploring the cardioprotective potentials of naringin (NRG) against 5-FU-induced cardiotoxicity in rats. We divided Wistar rats into four experimental groups (n = 6) for the administration of NRG (100 mg/kg bw, orally) and/or 5-FU (150 mg/kg bw, intraperitoneal). NRG was administered for 10 days, while 5-FU was injected on the 8th day only. Serum troponin-I (cTn-I) and creatine kinase (CK) were estimated. Cardiac activities/level of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), reduced glutathione (GSH), malondialdehyde (MDA), interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS) and nuclear factor-ĸB (NF-κB) and caspase-3 were determined. 5-FU markedly increased cTn-I, CK, cardiac inflammatory mediators and caspase-3 expressions, whereas antioxidant mediators decreased appreciably when compared to the control groups. Interestingly, the prophylactic administration of NRG prominently inhibited the 5-FU-provoked oxidative stress, pro-inflammation and apoptosis in the heart of rats. Histopathology confirmed the biochemical results of the heart. Therefore, NRG is a potential natural flavonoid for mitigation of 5-FU cardiotoxicity in rats.

Nrf2 Regulates Oxidative Stress and Its Role in Cerebral Ischemic Stroke

Cerebral ischemic stroke is characterized by acute ischemia in a certain part of the brain, which leads to brain cells necrosis, apoptosis, ferroptosis, pyroptosis, etc. At present, there are limited effective clinical treatments for cerebral ischemic stroke, and the recovery of cerebral blood circulation will lead to cerebral ischemia-reperfusion injury (CIRI). Cerebral ischemic stroke involves many pathological processes such as oxidative stress, inflammation, and mitochondrial dysfunction. Nuclear factor erythroid 2-related factor 2 (Nrf2), as one of the most critical antioxidant transcription factors in cells, can coordinate various cytoprotective factors to inhibit oxidative stress. Targeting Nrf2 is considered as a potential strategy to prevent and treat cerebral ischemia injury. During cerebral ischemia, Nrf2 participates in signaling pathways such as Keap1, PI3K/AKT, MAPK, NF-κB, and HO-1, and then alleviates cerebral ischemia injury or CIRI by inhibiting oxidative stress, anti-inflammation, maintaining mitochondrial homeostasis, protecting the blood-brain barrier, and inhibiting ferroptosis. In this review, we have discussed the structure of Nrf2, the mechanisms of Nrf2 in cerebral ischemic stroke, the related research on the treatment of cerebral ischemia through the Nrf2 signaling pathway in recent years, and expounded the important role and future potential of the Nrf2 pathway in cerebral ischemic stroke.

Naringinin ratlarda bakteriyel endotoksin kaynaklı ince bağırsak hasarı üzerindeki anti-inflamatuvar ve anti-apoptotik etkileri

Amaç. Bu çalışmanın amacı, birçok biyolojik özelliği bulunan naringinin (NRG) ratlarda bakteriyel endotoksin kaynaklı ince bağırsak hasarı üzerine anti-inflamatuar ve antiapoptotik etkilerinin araştırılmasıdır. Gereç ve Yöntem: Bu amaçla, 40 adet dişi Wistar albino ırkı rat 4 gruba ayrılmıştır: Kontrol (hiçbir uygulama yapılmayan grup), LPS (10 mg/kg/ip lipopolisakkarit uygulanan grup), NRG (14 gün boyunca 100 mg/kg/ip naringin uygulanan grup) ve LPS+NRG (10 mg/kg/ip lipopolisakkarit uygulamasından önce 14 gün boyunca naringin uygulanan grup). Deneysel prosedürün uygulanmasından sonra, deney hayvanlarının ince barsak dokuları çıkarıldı ve doku takibi protokolüne göre hazırlandı. Barsak dokusundaki histopatolojik değişiklikleri değerlendirmek amacıyla Hematoksilen-Eozin boyaması gerçekleştirildi ve histopatolojik değişiklikler açısından deney gruplarının karşılaştırılması amacıyla hasar skorlaması yapıldı. Ayrıca, immunohistokimyasal boyamalar ile TNF- ve Kaspaz-3 ekspresyon seviyeleri belirlendi ve gruplar arasında bu proteinlerin ekspresyon seviyelerindeki değişikliklerin belirlenmesi için immunohistokimyasal boyanma yoğunluğu skorlandı. Bulgular: LPS grubunda epitel ve Brunner bezlerinde hasar, mononüklear hücre infiltrasyonu, hemorajik alanlar belirlendi. Ayrıca TNF- ve Kaspaz-3 ekspresyonları bu grupta anlamlı bir şekilde arttı. Ancak, NRG uygulamaları bu parametreler açısından LPS+NRG grubundaki deney hayvanlarının ince barsak dokusunda güçlü bir koruyucu etki gösterdi. Sonuç: Bu çalışma, 100 mg/kg NRG enjeksiyonunun endotoksin kaynaklı enfeksiyonun bağırsak mukozası üzerindeki olumsuz etkilerine karşı koruyucu bir ajan olarak kabul edilebileceğini ve daha ileri klinik çalışmalarda göz ardı edilmemesi gerektiğini göstermiştir.

Short-term pretreatment of naringin isolated from Citrus wilsonii Tanaka attenuates rat myocardial ischemia/reperfusion injury

Pretreatment or treatment with anti-apoptotic, anti-inflammatory, or anti-oxidative approaches could be critical for attenuated the severity of myocardial ischemia/reperfusion (I/R) injury. Naringin, a natural flavonoid, plays important roles in inflammation-related diseases. Immature dry fruits of Citrus wilsonii Tanaka (Xiang Yuan) are rich in naringin that can be used as traditional Chinese medicine to treat inflammation-related symptoms. However, its roles in cardioprotective role remain unclear. This study aimed to isolate naringin from Citrus wilsonii Tanaka fruit and tested their cardioprotective effect. The dry fruits of Citrus wilsonii Tanaka were extracted with boiling water and then supernatants were freeze-dried to yield aqueous extract (ZQAE). The extract was chemoprofiled using UPLC-MS/MS to stand for major constituents, and then subjected to different chromatographic separation steps, and naringin was isolated in a high yield. The cardioprotective effects of the aqueous extract of ZQAE and naringin were investigated in a myocardial I/R rat model and to elucidate the mechanism underlying its cardioprotective effect. Our results indicated that 5-day ZQAE and naringin pretreatments both promoted histopathological changes and reduced myocardial enzymes (cTnl, CK-MB, CK and LDH) induced by I/R. Moreover, the 50 mg/kg and 100 mg/kg ZQAE dose pretreatments presented a significantly decreased infarct size as well as myocardial enzyme levels but also inhibited myocardial apoptosis (cleaved-caspase3 protein expression), the inflammatory response (IL-23, IL-6, and TNF-α) and oxidative stress (MDA and SOD). The cardioprotective effect of 5 mg/kg dose of naringin pretreatment is comparable with that of 5 mg/kg drug ditiazem pretreatment. Additionally, naringin pretreatment exhibited striking decreases in the apoptosis index and downregulation of the protein expression levels of cleaved-Caspase3, Bcl2 and Bax. Meanwhile, naringin downregulated HMGB1 expression and upregulated SIRT1 expression in the myocardium. These findings suggest that short-term pretreatments with ZQAE and naringin both protect against myocardial I/R injury by suppressing myocardial apoptosis, the inflammatory response, and oxidative stress. The cardioprotective effect of naringin involves SIRT1 activation and may interact with HMGB1 and inhibit the release of HMGB1.

Naringenin alleviates myocardial ischemia/reperfusion injury by regulating the nuclear factor-erythroid factor 2-related factor 2 (Nrf2) /System xc-/ glutathione peroxidase 4 (GPX4) axis to inhibit ferroptosis

Ferroptosis is an important form of myocardial cell death in myocardial ischemia-reperfusion injury (MIRI). Naringenin (NAR), as a flavonoid, has a significant advantage in improving MIRI. But the regulatory effect and mechanism of NAR on ferroptosis in MIRI have not been reported. After the rats were given NAR and induced to form myocardial ischemia-reperfusion (MI/R) injury, Tetrazolium chloride (TTC) staining was used to detect the myocardial infarction area of rats, and Hematoxylin-eosin (H&E) staining was used to detect myocardial injury. The markers of tissue inflammation were detected by ELISA. Serum creatine kinase Serum creatin kinase (CPK), Lactate dehydrogenase (LDH), and lipid peroxide (LPO) and oxidative stress related levels were measured. In addition, iron detection kits were used to detect total iron and Fe²⁺ levels in cardiac tissues, and western blot was used to detect the expression of ferroptosis-related proteins and the expression of nuclear factor-erythroid factor 2-related factor 2 (Nrf2) and glutathione peroxidase 4 (GPX4). At the cellular level, H9C2 cardiomyocytes were induced by hypoxia/reoxygenation (H/R), and ferroptosis inducer Erastin was administered to detect cell viability, ferroptosis-related indicators, oxidative stress related indicators, and expressions of Nrf2 and GPX4, to explore the mechanisms involved. NAR alleviated MI/R-induced pathological damage, inflammation and lipid peroxidation in myocardial tissue of rats. NAR adjusted the NRF2 /System xc – /GPX4 axis and improved ferroptosis. At the cellular level, ferroptosis inducer Erastin reversed the protective effect of NAR on H/R-induced H9C2 cardiomyocytes. In conclusion, NAR can alleviate MIRI by regulating the Nrf2/System xc-/GPX4 axis to inhibit ferroptosis.

Protective effects of naringin on valproic acid-induced hepatotoxicity in rats

Valproic acid (VPA) is mainly prescribed to treat epilepsy. VPA has been reported to be associated with many adverse effects, including hepatotoxicity. Naringin (NRG) is a natural, therapeutically active flavanone glycoside with anti-inflammatory, anti-apoptotic, and antioxidant. The current study was therefore designed to investigate the protective effect of NRG against the VPA-induced experimental hepatotoxicity model. For this purpose, 24 Wistar albino rats were randomly divided into three groups as control (Vehicle), VPA (500 mg/kg), and NRG + VPA (100 mg/kg NRG + 500 mg/kg VPA) groups. The agents were administered via oral gavage for 14 days. Blood and liver tissue samples were taken on the end of the experiment. Biochemical analyzes were performed on the blood and liver samples. Also, malondialdehyde (MDA), superoxide dismutase (SOD) enzyme, glutathione (GSH) content, catalase (CAT) enzyme levels were examined in the liver tissue samples. Histopathological changes (hydropic degeneration and congestion) in the VPA group were increased significantly when compared to the control group (p < 0.05). We also found a decrease in enzymes of serum liver function in the VPA group. However, NRG has been shown not to prevent histopathological changes in the VPA group. According to our results with this experiment protocol, NRG could not exert sufficient protection against VPA-induced hepatotoxicity.

Naringin attenuates rat myocardial ischemia/reperfusion injury via PI3K/Akt pathway-mediated inhibition of apoptosis, oxidative stress and autophagy

Naringin (NRG) has been reported to exert cardioprotective effects against multiple cardiovascular diseases, including lipopolysaccharide-induced and hyperglycemia-induced myocardial injury. However, the role of NRG in myocardial ischemia/reperfusion (I/R) injury remains unclear. In the present study, the PI3K/Akt pathway was investigated to evaluate the possible mechanisms underlying the roles of NRG in myocardial ischemia/reperfusion (I/R) injury. The levels of cardiac enzymes were measured by ELISA to evaluate the optimal dosage of NRG that could protect against myocardial I/R injury. Rats were administered 100 mg/kg of NRG and activities of myocardial enzymes, the level of cardiac apoptosis and inflammation, oxidant response, autophagy indicators and echocardiography were evaluated. The level of corresponding proteins was measured using western blotting. The results indicated that NRG elicited the best cardioprotective effects at a dose of 100 mg/kg by significantly reducing the levels of myocardial enzymes, apoptosis, inflammation, oxidative response and infarct size. Furthermore, NRG alleviated contractile dysfunction by increasing the left ventricular ejection fraction and fractional shortening. In addition, NRG markedly promoted the phosphorylation of Akt, while decreasing the level of autophagy indicator beclin-1 and the microtubule-associated protein 1B-light chain 3 (LC3B) II/ LC3BI ratio. However, PI3K/Akt inhibitor (LY294002) partially reduced the NRG induced phosphorylation of Akt and the reduction in beclin-1, along with the LC3BII/LC3BI ratio. The results of the present study demonstrated that NRG could attenuate myocardial I/R injury.