Cisplatin is a chemotherapeutic agent widely used to treat solid tumors. However, it can also be highly ototoxic, resulting in high-frequency hearing loss. Cisplatin causes degeneration of hair cells (HCs) and spiral ganglion neurons (SGNs) in the inner ear, which are essential components of the hearing process and cannot be regenerated in mammals. As the affected cells primarily die by apoptosis, we tested several anti-apoptotic small molecules to protect these cells from drug-induced toxicity. We found that the general caspase inhibitor Emricasan could significantly counteract the toxic effects of cisplatin in House Ear Institute-Organ of Corti 1 (HEI-OC1) cells, phoenix auditory cells, and primary SGNs. Importantly, the anti-cytotoxic effect in neuronal cells was even more pronounced than the effect of sodium thiosulfate (STS), which is currently the only approved prevention option for cisplatin-induced ototoxicity. Finally, we tested the protective effect of Emricasan treatment in the context of another ototoxic drug, i.e., the aminoglycoside antibiotic neomycin, and again found a significant increase in cell viability when the cultures were co-treated with Emricasan. These results suggest a promising strategy to prevent ototoxicity in patients by temporarily blocking the apoptotic pathway when applying cisplatin or aminoglycoside antibiotics. KEY MESSAGES: Anti-apoptotic small molecules can reduce cisplatin-induced toxicity. Emricasan can effectively exert its anti-apoptotic effect on cochlear cells. Strong protection from cisplatin- and neomycin-induced cytotoxicity with Emricasan. Sodium thiosulfate and Emricasan provide similar protective effects to cisplatin-treated cells. Emricasan is more potent than sodium thiosulfate in reducing neomycin-induced cytotoxicity.

Doxorubicin (Dox) is widely used as a chemotherapy drug, while anethole (AN) is primarily known as the main aromatic component in various plant species. This research focused on the impact of AN on the cardiac and renal toxicity induced by Dox and to understand the underlying mechanisms. For cardiac toxicity, Wistar rats were categorized into four groups: a Control group; a Dox group, where rats received 2.5 mg/kg of Dox intraperitoneally every other day; and two Dox + AN groups, where animals were administered Dox (2.5 mg/kg/every other day, IP) along with 125 mg/kg or 250 mg/kg of AN, respectively. The renal toxicity study included similar groups, with the Dox group receiving a single dose of 20 mg/kg of Dox intraperitoneally on the tenth day, and the Dox + AN groups receiving 125 mg/kg and 250 mg/kg of AN for two weeks, alongside the same dose of Dox (20 mg/kg, IP, once on the 10th day). Parameters assessed included ECG, cardiac injury markers (CK, CK-MB, and LDH), and kidney function tests (Cr, BUN, uric acid, LDL, Kim-1, NGAL, and CysC). Antioxidant activity, lipid peroxidation, inflammation, and apoptotic markers were also monitored in heart and renal tissues. Gene expression levels of the TLR4/MyD88/NFκB pathway, along with Bax and Bcl-2, were evaluated. Dox significantly altered ECG, elevated cardiac injury markers, and renal function markers. It also augmented gene expressions of TLR4/MyD88/NFκB, amplified oxidative stress, inflammatory cytokines and apoptotic markers. Conversely, AN reduced cardiac injury markers and kidney function tests, improved ECG, diminished TLR4/MyD88/NFκB gene expression, and alleviated oxidative stress by increasing antioxidant enzyme activities and reducing inflammatory cytokines. AN also enhanced Bcl-2 levels and inhibited Bax and the cleavage of caspase-3 and 9. AN countered the lipid peroxidation, oxidative stress, inflammation, and apoptosis induced by Dox, marking it as a potential preventive strategy against Dox-induced nephrotoxic and cardiotoxic injuries.

Tauroursodeoxycholic acid (TUDCA) is approved for the treatment of liver diseases. However, the antihyperglycemic effects/mechanisms of TUDCA are still less clear. The present study aimed to evaluate the antidiabetic action of TUDCA in streptozotocin (STZ)-induced type 2 diabetes mellitus (T2DM) in rats. Fifteen adult Wistar albino male rats were randomly divided into three groups (n = five in each): control, diabetic (STZ), and STZ+TUDCA. The results showed that TUDCA treatment significantly reduced blood glucose, HbA1c%, and HOMA-IR as well as elevated the insulin levels in diabetic rats. TUDCA therapy increased the incretin GLP-1 concentrations, decreased serum ceramide synthase (CS), improved the serum lipid profile, and restored the glycogen content in the liver and skeletal muscles. Furthermore, serum inflammatory parameters (such as TNF-α, IL-6, IL-1ß, and PGE-2) were substantially reduced with TUDCA treatment. In the pancreas, STZ+TUDCA-treated rats underwent an obvious enhancement of enzymatic (CAT and SOD) and non-enzymatic (GSH) antioxidant defense systems and a marked decrease in markers of the lipid peroxidation rate (MDA) and nitrosative stress (NO) compared to STZ-alone. At the molecular level, TUDCA decreased the pancreatic mRNA levels of iNOS and apoptotic-related factors (p53 and caspase-3). In conclusion, TUDCA may be useful for diabetes management and could be able to counteract diabetic disorders via anti-hyperlipidemic, antioxidant, anti-inflammatory, and anti-apoptotic actions.

Degenerative fundus disease encompasses a spectrum of ocular diseases, including diabetic retinopathy (DR) and age-related macular degeneration (AMD), which are major contributors to visual impairment and blindness worldwide. The development and implementation of effective strategies for managing and preventing the onset and progression of these diseases are crucial for preserving patients\' visual acuity. Melatonin, a neurohormone primarily produced by the pineal gland, exhibits properties such as circadian rhythm modulation, antioxidant activity, anti-inflammatory effects, and neuroprotection within the ocular environment. Furthermore, melatonin has been shown to suppress neovascularization and reduce vascular leakage, both of which are critical in the pathogenesis of degenerative fundus lesions. Consequently, melatonin emerges as a promising therapeutic candidate for degenerative ocular diseases. This review provides a comprehensive overview of melatonin synthesis, its localization within ocular tissues, and its mechanisms of action, particularly in regulating melatonin production, thereby underscoring its potential as a therapeutic agent for degenerative fundus diseases.

Stroke is an important medical problem in developing countries, characterized by a sudden disruption of blood supply to the brain, either through occlusion or hemorrhage. It is a major cause of neurological impairment, resulting in high medical costs. The present study examined the effect of 6-gingerol on morphological changes, antioxidant defenses, and the anti-apoptotic factors p38 mitogen-activated protein kinase (MAPK) and mitofusin (Mfn)2, in a rat model of focal cerebral ischemia. A total of 60 healthy male Wistar rats were randomly allocated into six groups: Control, right middle cerebral artery occlusion (Rt.MCAO) + vehicle, Rt.MCAO + piracetam, and Rt.MCAO + 6-Gin 5, 10 and 20 mg/kg BW groups. The results indicated that 6-gingerol treatment for a duration of 7 days reverses morphological alterations, enhances catalase and glutathione peroxidase activities, reduces Bax, caspase-3 and MAPK expression, and increases Bcl-xL and Mfn2 expression in the cortex and hippocampus. In conclusion, 6-gingerol demonstrated significant in vivo effectiveness in mitigating pathological changes induced by cerebral ischemia. This beneficial effect is attributed, at least in part, to preservation of antioxidant defenses and activation of anti-apoptotic pathways.

Ghrelin and its mimetics have been shown to reduce cisplatin-induced emesis in preclinical studies using ferrets and shrews. This study investigated the effectiveness of ghrelin and des-acyl ghrelin (DAG) in antagonizing cisplatin-induced emesis and physiological changes indicative of nausea in Suncus murinus. Animals implanted with radiotelemetry devices were administered ghrelin (0.2, 1.0, and 5.0 μg/day), DAG (0.2, 1.0, and 5.0 μg/day), or saline (14 μL/day) intracerebroventricularly 4 days before and 3 days after treatment with cisplatin (30 mg/kg). At the end, the anti-apoptotic potentials of ghrelin and DAG were assessed by measuring Bax expression and cytochrome C activity. Neurotransmitter changes in the brain were evaluated using liquid chromatography-mass spectrometry analysis. Ghrelin and DAG reduced cisplatin-induced emesis in the delayed (24-72 h) but not the acute phase (0-24 h) of emesis. Ghrelin also partially reversed the inhibitory effects of cisplatin on food intake without affecting gastrointestinal myoelectrical activity or causing hypothermia; however, ghrelin or DAG did not prevent these effects. Ghrelin and DAG could attenuate the cisplatin-induced upregulation of Bax and cytochrome C in the ileum. Cisplatin dysregulated neurotransmitter levels in the frontal cortex, amygdala, thalamus, hypothalamus, and brainstem, and this was partially restored by low doses of ghrelin and DAG. Our findings suggest that ghrelin and DAG exhibit protective effects against cisplatin-induced delayed emesis. The underlying antiemetic mechanism may involve GHSR and/or unspecified pathways that modulate the neurotransmitters involved in emesis control in the brain and an action to attenuate apoptosis in the gastrointestinal tract.

Dietary protein supplementation has emerged as a promising strategy in combating sarcopenia. Furthermore, searching for alternatives of animal proteins has been a hot topic. The present study aimed to investigate the effects of zein peptides on C2C12 myoblasts and explore their potential molecular mechanisms. The proliferative, cell cycle, and anti-apoptotic activities of zein peptides were evaluated. Peptidomics analysis and transcriptome sequencing were employed to explore the structure-activity relationship and underlying molecular mechanisms. The results indicated that zein peptides (0.05-0.2 mg/mL) exerted a significant proliferation-promoting impact on C2C12 cells, via increasing cell viability by 33.37 to 42.39%. Furthermore, zein peptides significantly increased S phase proportion and decreased the apoptosis rate from 34.08% (model group) to 28.96% in C2C12 cells. In addition, zein peptides exhibited a pronounced anti-apoptotic effect on C2C12 cells. Zein peptides are abundant in branch-chain amino acids, especially leucine. Transcriptomics analysis revealed that zein peptides can promote proliferation, accelerate cell cycle, and improve protein synthesis of muscle cells through mTORC1 and mTORC2 signaling pathways.

Cisplatin is a highly effective chemotherapeutic agent, but it can cause sensorineural hearing loss (SNHL) in patients. Cisplatin-induced ototoxicity is closely related to the accumulation of reactive oxygen species (ROS) and subsequent death of hair cells (HCs) and spiral ganglion neurons (SGNs). Despite various strategies to combat ototoxicity, only one therapeutic agent has thus far been clinically approved. Therefore, we have developed a gene therapy concept to protect cochlear cells from cisplatin-induced toxicity. Self-inactivating lentiviral (LV) vectors were used to ectopically express various antioxidant enzymes or anti-apoptotic proteins to enhance the cellular ROS scavenging or prevent apoptosis in affected cell types. In direct comparison, anti-apoptotic proteins mediated a stronger reduction in cytotoxicity than antioxidant enzymes. Importantly, overexpression of the most promising candidate, Bcl-xl, achieved an up to 2.5-fold reduction in cisplatin-induced cytotoxicity in HEI-OC1 cells, phoenix auditory neurons, and primary SGN cultures. BCL-XL protected against cisplatin-mediated tissue destruction in cochlear explants. Strikingly, in vivo application of the LV BCL-XL vector improved hearing and increased HC survival in cisplatin-treated mice. In conclusion, we have established a preclinical gene therapy approach to protect mice from cisplatin-induced ototoxicity that has the potential to be translated to clinical use in cancer patients.

BACKGROUND: Scrophulariae Radix (Xuanshen [XS]) has been used for several years to treat hyperthyroidism. However, its effective substances and pharmacological mechanisms in the treatment of hyperthyroidism and thyroid hormone-induced liver and kidney injuries have not yet been elucidated.
OBJECTIVE: This study aimed to explore the pharmacological material basis and potential mechanism of XS therapy for hyperthyroidism and thyroid hormone-induced liver and kidney injuries based on network pharmacology prediction and experimental validation.
METHODS: Based on 31 in vivo XS compounds identified using ultra-performance liquid chromatography tandem quadruple exactive orbitrap high-resolution accurate-mass spectrometry (UPLC-QE-HRMS), a network pharmacology approach was used for mechanism prediction. Systematic networks were constructed to identify the potential molecular targets, biological processes (BP), and signaling pathways. A component-target-pathway network was established. Mice were administered levothyroxine sodium through gavage for 30 d and then treated with different doses of XS extract with or without propylthiouracil (PTU) for 30 d. Blood, liver, and kidney samples were analyzed using an enzyme-linked immunosorbent assay (ELISA) and western blotting.
RESULTS: A total of 31 prototypes, 60 Phase I metabolites, and 23 Phase II metabolites were tentatively identified in the plasma of rats following the oral administration of XS extract. Ninety-six potential common targets between the 31 in vivo compounds and the diseases were identified. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that Bcl-2, BAD, JNK, p38, and ERK1/2 were the top targets. XS extract with or without PTU had the following effects: inhibition of T3/T4/fT3/fT4 caused by levothyroxine; increase of TSH levels in serum; restoration of thyroid structure; improvement of liver and kidney structure and function by elevating the activities of anti-oxidant enzymes catalase (CAT),superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px); activation anti-apoptotic proteins Bcl-2; inhibition the apoptotic protein p-BAD; downregulation inflammation-related proteins p-ERK1/2, p-JNK, and p-p38; and inhibition of the aggregation of pro-inflammatory cytokines TNF-α, IL-1β, and IL-6, as well as immune cells in the liver.
CONCLUSIONS: XS can be used to treat hyperthyroidism and liver and kidney injuries caused by thyroid hormones through its anti-oxidant, anti-inflammatory, and anti-apoptotic properties. In addition, serum pharmacochemical analysis revealed that five active compounds, namely 4-methylcatechol, sugiol, eugenol, acetovanillone, and oleic acid, have diverse metabolic pathways in vivo and exhibit potential as effective therapeutic agents.

Nowadays, it is well recognized that apoptosis, as a highly regulated cellular process, plays a crucial role in various biological processes, such as cell differentiation. Dysregulation of apoptosis is strongly implicated in the pathophysiology of numerous disorders, making it essential to comprehend its underlying mechanisms. One key factor that has garnered significant attention in the regulation of apoptotic pathways is HMG-CoA reductase degradation protein 1, also known as HRD1. HRD1 is an E3 ubiquitin ligase located in the endoplasmic reticulum (ER) membrane. Its primary role involves maintaining the quality control of ER proteins by facilitating the ER-associated degradation (ERAD) pathway. During ER stress, HRD1 aids in the elimination of misfolded proteins that accumulate within the ER. Therefore, HRD1 plays a pivotal role in the regulation of apoptotic pathways and maintenance of ER protein quality control. By targeting specific protein substrates and affecting apoptosis-related pathways, HRD1 could be an exclusive therapeutic target in different disorders. Dysregulation of HRD1-mediated processes contributes significantly to the pathophysiology of various diseases. The purpose of this review is to assess the effect of HRD1 on the pathways related to apoptosis in various diseases from a therapeutic perspective.