Otoprotective Effects of Zingerone on Cisplatin-Induced Ototoxicity

Melatonin alleviates ischemic stroke by inhibiting ferroptosis through the CYP1B1/ACSL4 pathway

This study utilized middle cerebral artery occlusion (MCAO) mouse models and HT-22 cell oxygen and glucose deprivation/reoxygenation (OGD/R) models to investigate the therapeutic effects of melatonin on ischemic brain injury. In the experiments, MCAO mice were treated with 5 and 10 mg/kg doses of melatonin, and H-T22 cells underwent OGD/R treatment and were administered different concentrations of melatonin. The results showed that melatonin significantly reduced ischemic brain area, neural damage, cerebral edema, and neuronal apoptosis in MCAO mice. In the HT-22 cell model, melatonin also improved cell proliferation ability, reduced apoptosis, and ROS production. Further mechanistic studies found that melatonin exerts protective effects by inhibiting ferroptosis, an iron-dependent form of regulated cell death, through regulation of the ACSL4/CYP1B1 pathway. In MCAO mice, melatonin decreased lipid peroxidation, ROS production, and ACSL4 protein expression. Overexpression of CYP1B1 increased ACSL4 ubiquitination and degradation, thereby increasing cell tolerance to ferroptosis, reducing ACSL4 protein levels, and decreasing ROS production. CYP1B1 knockdown obtained opposite results. The CYP1B1 metabolite 20-HETE induces expression of the E3 ubiquitin ligase FBXO10 by activating PKC signaling, which promotes ACSL4 degradation. In the OGD/R cell model, inhibition of CYP1B1 expression reversed the therapeutic effects of melatonin. In summary, this study demonstrates that melatonin protects the brain from ischemic injury by inhibiting ferroptosis through regulation of the ACSL4/CYP1B1 pathway, providing evidence for new therapeutic targets for ischemic brain injury.

Research progress of ginger in the treatment of gastrointestinal tumors

Cancer seriously endangers human health. Gastrointestinal cancer is the most common and major malignant tumor, and its morbidity and mortality are gradually increasing. Although there are effective treatments such as radiotherapy and chemotherapy for gastrointestinal tumors, they are often accompanied by serious side effects. According to the traditional Chinese medicine and food homology theory, many materials are both food and medicine. Moreover, food is just as capable of preventing and treating diseases as medicine. Medicine and food homologous herbs not only have excellent pharmacological effects and activities but also have few side effects. As a typical medicinal herb with both medicinal and edible uses, some components of ginger have been shown to have good efficacy and safety against cancer. A mass of evidence has also shown that ginger has anti-tumor effects on digestive tract cancers (such as gastric cancer, colorectal cancer, liver cancer, laryngeal cancer, and pancreatic cancer) through a variety of pathways. The aim of this study is to investigate the mechanisms of action of the main components of ginger and their potential clinical applications in treating gastrointestinal tumors.

Zingerone attenuates intestinal injury and colitis caused by a high-fat diet through Nrf2 signaling regulation

This study examined the protective effect of Zingerone against a high-fat diet (HFD)-induced intestinal damage. Control and HFD rats were treated with the vehicle or Zingerone (100 mg/kg, orally) (n = 8 rats/groups). An extra group, HFD + Zingerone + brusatol (an Nrf2 inhibitor). This study treatment lasted four weeks. Zingerone reduced the nuclear levels of NF-B p65 in control and HFD-fed rats while increasing SOD, CAT, GSH, levels of mRNA, cytoplasmic levels, and Nrf2 nuclear levels. Zingerone treatment attenuated the duodenal epithelial damage and maintained the mucosal barrier by reducing plasma FITC-DX and serum LPS in rats fed with HFD. Concomitantly, it lowered the duodenal MDA, TNF-α, IL-6, and IL-1β levels. These impacts included changes in body weight, duodenal lipid levels, and Keap-1 expression, a natural Nrf2 inhibitor. We concluded that Zingerone reduces HFD-induced duodenal injury. These findings support Zingerone's clinical applicability against various inflammatory diseases of the intestine.

Effects of natural products on cisplatin ototoxicity and chemotherapeutic efficacy

INTRODUCTION

Cisplatin is a very effective chemotherapeutic agent against a variety of solid tumors. Unfortunately, cisplatin causes permanent sensorineural hearing loss in at least two-thirds of patients treated. There are no FDA approved drugs to prevent this serious side effect.

AREAS COVERED

This paper reviews various natural products that ameliorate cisplatin ototoxicity. These compounds are strong antioxidants and anti-inflammatory agents. This review includes mostly preclinical studies but also discusses a few small clinical trials with natural products to minimize hearing loss from cisplatin chemotherapy in patients. The interactions of natural products with cisplatin in tumor-bearing animal models are highlighted. A number of natural products did not interfere with cisplatin anti-tumor efficacy and some agents actually potentiated cisplatin anti-tumor activity.

EXPERT OPINION

There are a number of natural products or their derivatives that show excellent protection against cisplatin ototoxicity in preclinical studies. There is a need to insure uniform standards for purity of drugs derived from natural sources and to ensure adequate pharmacokinetics and safety of these products. Natural products that protect against cisplatin ototoxicity and augment cisplatin's anti-tumor effects in multiple studies of tumor-bearing animals are most promising for advancement to clinical trials. The most promising natural products include honokiol, sulforaphane, and thymoquinone.

Effects of acute exposure to Al2O3-NPs (α and γ) and white noise and their combination on cochlea structure and function in Wistar rats

Hearing loss induced by noise and combinations of factors is a common occupational disease among workers. This study aimed to investigate the impact of acute exposure to white noise and Al2O3 NPs, alone and in combination, on changes in the hearing and structural functions of the cochlea in rats. Thirty-six rats were randomly assigned to one of six groups: Control, acute exposure to white noise, exposure to γ-Al2O3 NPs, exposure to noise plus γ-Al2O3 NPs, exposure to α-Al2O3 NPs, and exposure to the combination of noise plus α-Al2O3 NPs. TTS and PTS were examined using DPOAE, while oxidative index (MDA, GSH-Px), gene expression (NOX3, TGF-ß, CYP1A1), protein expression (ß-Tubulin, Myosin VII), and histopathological changes were examined in the cochlea. The morphology of Al2O3 NPs was examined by TEM. The results of the DPOAE test showed a significant increase in TTS in all groups and an increase in PTS in the groups exposed to noise, γ-Al2O3 NPs, and a combination of noise plus Al2O3 NPs (P < 0.05). In the group exposed to white noise plus Al2O3 NPs, the MDA levels increased, the level of GSH-Px decreased, and the expression percentage of ß-Tubulin and Myosin VII decreased, while the expression of NOX3, TGF-ß, and CYP1A1 (except for the α-Al2O3 NPs group) significantly increased (P < 0.05). Histopathological changes of the cochlea indicated damage to hair and ganglion cells, which was more severe in the combined exposure group. The combined and independent exposure to white noise and Al2O3 NPs damaged hair and ganglion cells for high-frequency perception, affecting the function and structure of the cochlea and leading to TTS and PTS.

Paklitakselin neden olduğu oksidatif hasara karşı farnesenin otoprotektif etkileri

Amaç: Bu çalışmanın amacı, güçlü serbest radikal süpürücü ve antioksidan özelliklere sahip farnesenin paklitaksel kaynaklı ototoksisite üzerindeki etkilerini biyokimyasal ve fonksiyonel yönden araştırmaktır. Gereç ve Yöntem: On sekiz erkek Wistar albino sıçan, altı sıçandan oluşan üç gruba rastgele ayrıldı. Araştırma boyunca kontrol grubuna paklitaksel veya farnesen verilmedi. Paklitaksel grubuna, 5mg/kg paklitaksel intraperitoneal olarak dört kez (1., 7., 14. ve 21. günlerde) verildi. Farnesen + paklitaksel grubuna, önce 5 mg/kg paklitaksel, 30 dakika sonra 50 mg/kg farnesen intraperitoneal olarak 4 kez (1., 7., 14. ve 21. günlerde) verildi. 0. ve 21. günlerde tüm sıçanların otoakustik emisyon ölçümü yapıldı. Daha sonra hayvanlar sakrifiye edildi ve biyokimyasal testler için kokleaları çıkarıldı. Bulgular: Paklitaksel, önemli ölçüde malondialdehit seviyelerini yükselterek ve glutatyon seviyelerini düşürerek kokleada oksidatif strese neden oldu. Ayrıca paklitaksel grubunun distorsiyon ürünü otoakustik emisyon değerleri diğer gruplara göre anlamlı derecede düşüktü. Farnesen+paklitaksel grubunda ise paklitakselin çeşitli biyokimyasal ve fonksiyonel parametrelerde oluşturduğu hasarda iyileşmeler gözlendi. Sonuç: Çalışma sonuçları doğal bir antioksidan olan farnesen’in sıçanlarda paklitaksel kaynaklı işitme kaybını azalttığını, farnesen ve paklitaksel kombinasyonunun gelecekte klinik kullanım için paklitaksel kaynaklı ototoksisiteden koruyabileceğini göstermektedir.

Zingerone ameliorates non-alcoholic fatty liver disease in rats by activating AMPK

This study was conducted to test the protective potential of Zingerone against a high-fat diet (HFD)-mediated non-alcoholic fatty liver disease (NAFLD) development in rats and examined in this protection is mediated modulating AMP-activated protein kinase (AMPK). Animals were segregated based on their diet and treatment into four groups (n = 6 each): (a) fed standard diet (STD), (b) treated with Zingerone (100 mg/kg), (c) fed HFD, (d) HFD + Zingerone (100 mg/kg), and (e) HFD + Zingerone (100 mg/kg) + compound c (CC) (an AMPK inhibitor) (0.2 mg/kg). The treatment with Zingerone attenuated the gain in final body weights, preserved liver structure, and downregulated the transcription of Bax and cleaved caspase-3. In the HFD and STD-fed rats, Zingerone reduced levels of fasting glucose and insulin and circulatory levels of cholesterol (CHOL) and triglycerides (TGs). Concomitantly, Zingerone enhanced glutathione (GSH) and superoxide dismutase (SOD) levels, depleted levels of malondialdehyde (MDA), and enhanced the nuclear levels of the nuclear factor erythroid 2-related factor 2 (Nrf2). In addition, it lowered the levels of inflammatory cytokines and the nuclear levels of the nuclear factor kappa beta p65 (NF-κB p65). All these biochemical changes were associated with an increment in the phosphorylation of AMPK (p-AMPK) (activation) and reduced mRNA levels of SREBP1 and SREBP2. All observed effects afforded by Zingerone were abolished by CC. In conclusion, Zingerone prevents hepatic oxidative stress, inflammation, and apoptosis by activating AMPK. PRACTICAL APPLICATIONS: The findings of this study identified Zingerone, isolated from ginger, as a very effective drug that not only can attenuate fasting hyperglycemia and hyperlipidemia, but also prevent hepatic deposition, steatosis, and oxidative damage induced by high-fat-fed rats by activating the AMPK/Nrf2 antioxidant axis and concomitant suppression of SREBP1, SREBp2, and NF-κB p65. These data list Zingerone as a potent stimulator of AMPK which suggests an effective strategy to treat and alleviate NAFLD and encourages further translational and clinical trials.

Regulation of ACSL4-Catalyzed Lipid Peroxidation Process Resists Cisplatin Ototoxicity

Cisplatin-induced ototoxicity is one of the common side effects during its treatment and there are no effective measures to prevent it. Our study aimed to investigate the effect of ACSL4-catalyzed lipid peroxidation on cisplatin-induced hearing loss and its possible protective mechanisms. We used a variety of cisplatin ototoxicity models, including HEI-OC1 cell line, cochlear explants, and ET4 GFP+ zebrafish. After measuring the experimental concentrations of cisplatin by CCK8 assay and immunofluorescence, respectively, we examined the levels of lipid peroxidation by MDA content, 4-HNE content, and C11-BODIPY (581/591) probe. Then, we used two ferroptosis inhibitors, FER-1, and Vit-E to protect hair cells. We found that cisplatin significantly increased the levels of lipid peroxidation and that this process can be resisted by the ferroptosis inhibitors. Afterwards, we performed metabolomic assays on the cisplatin-treated hair cells. The metabolite levels were significantly altered in the experimental group compared to the control group, and the highest degree of change was observed in the glutathione metabolic pathway and the arachidonic acid metabolic pathway. Therefore, we screened the key enzymes on the arachidonic acid metabolic pathway in the hair cells after cisplatin treatment and found that ACSL4 had the greatest regulatory value. Further, we reduced the level of lipid peroxide in hair cells by specifically inhibiting the expression of ACSL4, which protected hair cells from cisplatin damage at source. In conclusion, the lipid peroxidation process regulated by ACSL4 may be an important factor contributing to the sensitivity of hair cells to cisplatin. Inhibition of ACSL4 expression may be an effective preventive measure against cisplatin ototoxicity.

Zingerone Inhibits the Neutrophil Extracellular Trap Formation and Protects against Sepsis via Nrf2-Mediated ROS Inhibition

Neutrophils release chromatin and antimicrobial proteins to trap and kill microbes, which is termed as neutrophil extracellular trap (NET) formation. NETs play a pivotal role in host defense against infection. However, emerging evidence indicated that NETs also contribute to an exaggerated inflammatory response and organic injuries in sepsis. Zingerone, a natural compound extracted from Zingiber officinale, exerts antioxidant, anti-inflammatory, and antioncogenic properties. In this study, we found that treatment with zingerone reduced organ injury and improved the outcome in a cecal ligation puncture- (CLP-) induced polymicrobial sepsis model. Administration of zingerone also alleviates reactive oxygen species (ROS) accumulation and systematic inflammation in septic mice and inhibits neutrophil extracellular traps (NETs) formation in vivo and in vitro. Furthermore, inhibition of nuclear factor erythroid 2-related factor 2 (Nrf2) with its specific antagonist significantly counteracted the suppressive effects of zingerone on ROS and NETs and retarded the protective role of zingerone against sepsis-associated organ injury. In addition, exposure to zingerone does not affect phagocytic activity of neutrophils in vitro and bacterial dissemination in vivo. Above all, our results indicate that zingerone treatment obviously attenuates NET formation and inflammatory response via Nrf2-mediated ROS inhibition, thus providing a novel therapeutic strategy against sepsis-induced injury.

Transcriptomic analysis of rat kidney reveals a potential mechanism of sex differences in susceptibility to cisplatin-induced nephrotoxicity

Although cisplatin is an effective platinum-based anticancer drug against solid cancer, its availability is limited owing to its adverse side effects. Our study aimed to identify the potential relationship within cisplatin-induced multi-organ physiological changes and genetic factors associated with sex differences in nephrotoxicity susceptibility. To investigate this, mice received a single intraperitoneal injection of cisplatin. Cisplatin administration resulted in renal dysfunction, as evidenced by the elevation in serum biomarkers of renal damage (blood urea nitrogen and creatinine) and the degree of histopathological alterations. In particular, along with testicular damage and low testosterone levels, we also observed a decrease in male-specific (CYP3A2) or male-dominant (CYP2B1 and CYP3A1) CYP isoforms in the livers of rats with hepatotoxicity following cisplatin treatment, which may be associated with an imbalance in male hormone regulation caused by renal and testicular injury. Notably, we found that male rats were more susceptible to cisplatin-induced nephrotoxicity, as characterized by histopathological and biochemical analyses. Therefore, RNA sequencing was performed at baseline (pre-treatment) and at 48 h following cisplatin administration (post-treatment) to identify the genes associated with sex differences in nephrotoxicity susceptibility. Gap junctions, which play a role in replenishing damaged cells to maintain tissue homeostasis, and mismatch repair associated with a pathological apoptotic mechanism against cisplatin nephrotoxicity were significantly enriched only in males following cisplatin treatment. Moreover, among the 322 DEGs showing different basal expression patterns between males and females before cisplatin treatment, the male expressed high levels of genes, which are responsible for transmembrane transport and regulation of apoptotic process, pre-cisplatin treatment; additionally, genes involved in the PI3K-Akt signaling pathway and the oxidation-reduction process were significantly lower in males before cisplatin treatment. Collectively, our comprehensive findings provided valuable insight into the potential mechanisms of sex differences in cisplatin-induced nephrotoxicity susceptibility.

The protective role of Zingerone in a murine asthma model via activation of the AMPK/Nrf2/HO-1 pathway

Asthma is one of the most common illnesses associated with chronic airway inflammation; however, there are currently no effective therapies apart from glucocorticoids. Zingerone (ZIN), an active compound isolated from ginger, has been reported to have a broad spectrum of pharmacological properties. In this study, Zingerone was administrated to H₂O₂-stimulated mouse airway epithelial cell line MLE12 cells and asthmatic mice. The concentration of cytokines was evaluated using enzyme-linked immunosorbent assay (ELISA). Hematoxylin-eosin (HE), Periodic Acid-Schiff (PAS) and Masson staining were used for histological analyses. Protein levels in cells or lung tissues were determined using western blot, immunohistochemistry staining. The results showed that treatment with Zingerone dramatically inhibited oxidative stress and the inflammatory response in MLE12 cells stimulated with H₂O₂ and asthmatic mice. Furthermore, Zingerone treatment could decrease the expression of phosphorylated (p)-IκBα and p65 (nuclear) and increase the expression of phosphorylation of AMP-activated protein kinase (p-AMPK), nuclear factor erythroid-2-related factor 2 (Nrf2), and hemeoxygenase-1 (HO-1) to alleviate oxidative damage and inflammation both in vivo and in vitro. In addition, Zingerone treatment reduced the exudation and infiltration of inflammatory cells and suppressed goblet cell hyperplasia in a murine asthma model. Treatment with Zingerone also decreased the level of interleukin (IL)-4, IL-5, IL-13, and increased the level of interferon gamma (IFN-γ) in the BALF and attenuated airway hyperresponsiveness (AHR). However, inhibition of AMPK or Nrf2 suppressed the cellular protective, antioxidative, and anti-inflammatory properties of Zingerone. Taken together, these results demonstrate that Zingerone possesses the potential to relieve asthma via upregulating the AMPK/Nrf2/HO-1 signaling pathway.

Dose-Dependent Effects of Resveratrol on Cisplatin-Induced Hearing Loss

Previous preclinical studies have demonstrated the otoprotective effects of resveratrol (RV) at low doses. This study aimed to investigate the dose-dependent effects of RV in rats with cisplatin (CXP)-induced hearing loss. Sprague-Dawley rats (8-weeks old) were divided into six treatment groups (n = 12/group) and treated as follows: control, 0.5 mg/kg RV, 50 mg/kg RV, CXP, 0.5 mg/kg RV + CXP), and 50 mg/kg RV + CXP groups. CXP (3 mg/kg) was intraperitoneally injected for 5 days. RV (0.5 or 50 mg/kg) was intraperitoneally injected for 10 days from the first day of CXP administration. Auditory brainstem response (ABR) thresholds were measured before and within 3 days at the end of the drug administration. Cochlear tissues were harvested, and the outer hair cells were examined using cochlear whole mounts. The mRNA expression of NFκB, IL6, IL1β, and CYP1A1, and protein levels of aryl hydrocarbon receptor (AhR) and cytosolic and nuclear receptor for advanced glycation endproducts (RAGE) were evaluated. The ABR threshold increased in the 50 mg/kg RV and CXP groups at 4, 8, 16, and 32 kHz. The 0.5 mg/kg RV + CXP group demonstrated decreased hearing thresholds at 4 and 32 kHz compared to the CXP group. Cochlear whole-mount analysis revealed loss of outer hair cells in the 50 mg/kg RV and CXP groups and partial prevention of these cells in the 0.5 mg/kg RV + CXP group. The mRNA expressions of NFκB, IL6, and IL1β were increased in the 50 mg/kg RV and CXP groups compared to the control group. In contrast, these levels were decreased in the 0.5 mg/kg RV + CXP group compared to the CXP group. The mRNA expression of CYP1A1 was increased in the CXP group, while it was decreased in the 0.5 mg/kg RV + CXP group compared to the control group. The protein levels of AhR and cytosolic RAGE decreased in the 0.5 mg/kg RV group. Low-dose RV had partial otoprotective effects on CXP ototoxicity. The otoprotective effects of RV may be mediated through anti-oxidative (CYP1A1 and RAGE) and anti-inflammatory (NFκB, IL6, and IL1β) responses. High-dose RV exerted an inflammatory response and did not ameliorate CXP-induced ototoxicity.