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Although diabetic encephalopathy (DE) is a major late complication of diabetes, the pathophysiology of postural instability in DE remains poorly understood. Prior studies have suggested that neuronal apoptosis is closely associated with cognitive function, but the mechanism remains to be elucidated. Green tea, which is a non‑fermented tea, contains a number of tea polyphenols, alkaloids, amino acids, polysaccharides and other components. Some studies have found that drinking green tea can reduce the incidence of neurodegenerative diseases and improve cognitive dysfunction. We previously found that myosin light chain kinase (MLCK) regulates apoptosis in high glucose‑induced hippocampal neurons. In neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease, activation of the JNK signaling pathway promotes neuronal apoptosis. However, the relationship between JNK and MLCK remains to be elucidated. Green tea serum was obtained using seropharmacological methods and applied to hippocampal neurons. In addition, a type 1 diabetes rat model was established and green tea extract was administered, and the Morris water maze test, Cell Counting Kit‑8 assays, flow cytometry, western blotting and terminal deoxynucleotidyl transferase‑mediated dUTP nick end‑labelling assays were used to examine the effects of green tea on hippocampal neuronal apoptosis in diabetic rats. The results demonstrated that green tea can protect against hippocampal neuronal apoptosis by inhibiting the JNK/MLCK pathway and ultimately improves cognitive function in diabetic rats. The present study provided novel insights into the neuroprotective effects of green tea.

Diet and exercise are the most effective approaches used to induce weight loss. D‑psicose is a low‑calorie sweetener that has been shown to reduce weight in obese individuals. However, the effect of D‑psicose on muscle cells under oxidative stress, which is produced during exercise, requires further investigation. The present study aimed to determine the effects of D‑psicose on C2C12 myogenic cells in vitro. Hydrogen peroxide (H 2 O 2 ) was used to stimulate the generation of intracellular reactive oxygen species (ROS) in muscle cells to mimic exercise conditions. Cell viability was analyzed using a MTT assay and flow cytometry was used to analyze the levels of apoptosis, mitochondrial membrane potential (MMP), the generation of ROS and the cell cycle distribution following treatment. Furthermore, protein expression levels were analyzed using western blotting and cell proliferation was determined using a colony formation assay. The results of the present study revealed that D‑psicose alone exerted no toxicity on C2C12 mouse myogenic cells. However, in the presence of low‑dose (100  µ M) H 2 O 2 ‑induced ROS, D‑psicose induced C2C12 cell injury and significantly decreased C2C12 cell viability in a dose‑dependent manner. In addition, the levels of apoptosis and the generation of ROS increased, while the MMP decreased. MAPK family molecules were also activated in a dose‑dependent manner following treatment. Notably, the combined treatment induced G 2 /M phase arrest and reduced the proliferation of C2C12 cells. In conclusion, the findings of the present study suggested that D‑psicose may induce toxic effects on muscle cells in a simulated exercise situation by increasing ROS levels, activating the MAPK signaling pathway and disrupting the MMP.

Gentamicin (GEN) is a kind of aminoglycoside antibiotic with the adverse effect of nephrotoxicity. Currently, no effective measures against the nephrotoxicity have been approved. In the present study, epigallocatechin gallate (EG), a useful ingredient in green tea, was used to attenuate its nephrotoxicity. EG was shown to largely attenuate the renal damage and the increase of malondialdehyde (MDA) and the decrease of glutathione (GSH) in GEN-injected rats. In NRK-52E cells, GEN increased the cellular ROS in the early treatment phase and ROS remained continuously high from 1.5 H to 24 H. Moreover, EG alleviated the increase of ROS and MDA and the decrease of GSH caused by GEN. Furthermore, EG activated the protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). After the treatment of GEN, the protein level of cleaved-caspase-3, the flow cytometry analysis and the JC-1 staining, the protein levels of glutathione peroxidase 4 (GPX4) and SLC7A11, were greatly changed, indicating the occurrence of both apoptosis and ferroptosis, whereas EG can reduce these changes. However, when Nrf2 was knocked down by siRNA, the above protective effects of EG were weakened. In summary, EG attenuated GEN-induced nephrotoxicity by suppressing apoptosis and ferroptosis.

Sepsis is a systemic inflammatory response syndrome caused by infection, following with acute injury to multiple organs. Sepsis-induced acute kidney injury (AKI) is currently recognized as one of the most severe complications related to sepsis. The pathophysiology of sepsis-AKI involves multiple cell types, including macrophages, vascular endothelial cells (ECs) and renal tubular epithelial cells (TECs), etc. More significantly, programmed cell death including apoptosis, necroptosis and pyroptosis could be triggered by sepsis in these types of cells, which enhances AKI progress. Moreover, the cross-talk and connections between these cells and cell death are critical for better understanding the pathophysiological basis of sepsis-AKI. Mitochondria dysfunction and oxidative stress are traditionally considered as the leading triggers of programmed cell death. Recent findings also highlight that autophagy, mitochondria quality control and epigenetic modification, which interact with programmed cell death, participate in the damage process in sepsis-AKI. The insightful understanding of the programmed cell death in sepsis-AKI could facilitate the development of effective treatment, as well as preventive methods.

Gentamicin (GEN) is a kind of aminoglycoside antibiotic with the adverse effect of nephrotoxicity. Currently, no effective measures against the nephrotoxicity have been approved. In the present study, epigallocatechin gallate (EG), a useful ingredient in green tea, was used to attenuate its nephrotoxicity. EG was shown to largely attenuate the renal damage and the increase of malondialdehyde (MDA) and the decrease of glutathione (GSH) in GEN-injected rats. In NRK-52E cells, GEN increased the cellular ROS in the early treatment phase and ROS remained continuously high from 1.5 H to 24 H. Moreover, EG alleviated the increase of ROS and MDA and the decrease of GSH caused by GEN. Furthermore, EG activated the protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). After the treatment of GEN, the protein level of cleaved-caspase-3, the flow cytometry analysis and the JC-1 staining, the protein levels of glutathione peroxidase 4 (GPX4) and SLC7A11, were greatly changed, indicating the occurrence of both apoptosis and ferroptosis, whereas EG can reduce these changes. However, when Nrf2 was knocked down by siRNA, the above protective effects of EG were weakened. In summary, EG attenuated GEN-induced nephrotoxicity by suppressing apoptosis and ferroptosis. [ABSTRACT FROM AUTHOR]

Most cancer therapies are suffering from side effects to varying degrees, which might compromise the body functions and long-term health of patients. Balancing treatment efficacy and side effects has become a priority. Inspired by the concept that cellular ion homeostasis can lead to apoptosis, we developed a novel therapeutic strategy by incorporating the K+ transporter valinomycin into liposomes (Lipo-VM). Valinomycin is a naturally occurring polypeptide showing good biodegradation in vivo with reduced long-term side effects. Lipo-VM facilitates the K+ efflux of cells and triggers a caspase-dependent pathway of apoptosis by causing the collapse of mitochondrial membrane potential. With the help of a liposome-based nano-delivery system, Lipo-VM shows enhanced cell uptake and accumulation at the tumor site, which results in significant inhibition of tumor growth in a liver cancer model. The proposed valinomycin-anchored liposome provides an efficient and safe approach for cancer therapy. [Display omitted] • A cancer therapeutic system of valinomycin-anchored liposomes (Lipo-VM) is proposed. • Lipo-VM shows enhanced cell uptake and accumulation at the tumor site. • Cell membrane fused Lipo-VM facilitates K+ efflux of cells inhibiting tumor growth. • A caspase-dependent pathway of apoptosis is proposed. • Lipo-VM provides an efficient and safe approach for cancer therapy. [ABSTRACT FROM AUTHOR]

Pancreatic progenitor cell differentiation and proliferation factor (PPDPF) has been reported to play a role in tumorigenesis. However, its function in hepatocellular carcinoma (HCC) remains poorly understood. In this study, we report that PPDPF is significantly downregulated in HCC and the decreased PPDPF expression indicates poor prognosis. In the dimethylnitrosamine (DEN)-induced HCC mouse model, hepatocyte-specific depletion of Ppdpf promotes hepatocarcinogenesis, and reintroduction of PPDPF into liver-specific Ppdpf knockout (LKO) mice inhibits the accelerated HCC development. Mechanistic study shows that PPDPF regulates nuclear factor κB (NF-κB) signaling through modulation of RIPK1 ubiquitination. PPDPF interacts with RIPK1 and facilitates K63-linked ubiquitination of RIPK1 via recruiting the E3 ligase TRIM21, which catalyzes K63-linked ubiquitination of RIPK1 at K140. In addition, liver-specific overexpression of PPDPF activates NF-κB signaling and attenuates apoptosis and compensatory proliferation in mice, which significantly suppresses HCC development. This work identifies PPDPF as a regulator of NF-κB signaling and provides a potential therapeutic candidate for HCC. [Display omitted] • Decreased expression of PPDPF is associated with poor prognosis of patients with HCC • PPDPF promotes TRIM21-mediated ubiquitination of RIPK1 and facilitates NF-κB activation • Hepatic deletion of PPDPF leads to increased apoptosis and compensatory proliferation • Liver-specific overexpression of PPDPF significantly suppresses HCC development PPDPF plays an important role in HCC development. Wang et al. show that PPDPF exerts beneficial effects through modulating the TRIM21-mediated ubiquitination of RIPK1 and activation of NF-κB signaling. PPDPF may be a promising therapeutic candidate for the treatment of HCC. [ABSTRACT FROM AUTHOR]

A widely used type II pyrethroid pesticide cypermethrin (CYP) is one of endocrine disrupting chemicals (EDCs) with anti-androgenic activity to induce male reproductive toxicology. However, the mechanisms have not been fully elucidated. This study was to explore the effects of CYP on apoptosis of mouse Sertoli cells (TM4) and the roles of endoplasmic reticulum (ER)-mitochondria coupling involving 1,4,5-trisphosphate receptor type1-glucose-regulated protein 75-voltage-dependent anion channel 1 (IP3R1-GRP75-VDAC1). TM4 were cultured with different concentrations of CYP. Flow cytometry, calcium (Ca2+) fluorescent probe, transmission electron microscopy and confocal microscopy, and western blot were to examine apoptosis of TM4, mitochondrial Ca2+, ER-mitochondria coupling, and expressions of related proteins. CYP was found to increase apoptotic rates of TM4 significantly. CYP was shown to significantly increase expressions of cleaved caspase-3, cleaved poly ADP-ribose polymerase (PARP). Concentration of mitochondrial Ca2+ was increased by CYP treatment significantly. CYP significantly enhanced ER-mitochondria coupling. CYP was shown to increase expressions of IP3R, Grp75 and VDAC1 significantly. We suggest that CYP induces apoptosis in TM4 cells by facilitating mitochondrial Ca2+ overload regulated by ER-mitochondria coupling involving IP3R1-GRP75-VDAC1. This study identifies a novel mechanism of CYP-induced apoptosis in Sertoli cells. [Display omitted] • Cypermethrin (CYP) induces Sertoli cells apoptosis. • CYP mediates apoptosis by endoplasmic reticulum (ER)-mitochondrial coupling. • CYP induces apoptosis by ER-mitochondrial coupling involving IP3R1-GRP75-VDAC1. [ABSTRACT FROM AUTHOR]

Cypermethrin (CYP) has been identified as one kind of endocrine-disrupting chemicals (EDCs) to induce male reproduction damage. This study aimed to investigate the effects and mechanisms of miR-30a-5p on CYP induced apoptosis of TM4 mouse Sertoli cells in vitro. In the present study, 0 μM, 10 μM, 20 μM, 40 μM and 80 μM CYP were used to treat TM4 cells for 24 h. The apoptosis of TM4 cells, the expression level of miR-30a-5p, the protein expressions and the interaction between miR-30a-5p and KLF9 were detected by flow cytometry, quantitative Real-Time PCR, Western blot and luciferase reporter assays. CYP induced apoptosis of TM4 cells, inhibited expression of miR-30a-5p in TM4 cells, and overexpression of miR-30a-5p partially recovered CYP induced cells apoptosis. Furthermore, KLF9 was a potential downstream target of miR-30a-5p predicted by publicly available databases. KLF9 expression level in TM4 cells was significantly elevated after treatment with CYP, and the induction was inhibited by miR-30a-5p mimics transfection. Meanwhile, dual-luciferase reporter assay demonstrated that miR-30a-5p directly targeted KLF9–3′UTR. Moreover, in the presence of CYP, the apoptosis regulator p53 expression was also increased in TM4 cells. Overexpression miR-30a-5p or down-regulation of KLF9 both attenuated the induction of CYP on p53 expression. Overall, the present study demonstrated that miR-30a-5p regulated CYP induced TM4 cells apoptosis by targeting KLF9/p53 axis. • miR-30a-5p regulated cypermethrin-induced apoptosis of TM4 cells. • KLF9 was a downstream target of miR-30a-5p. • miR-30a-5p regulated TM4 cells apoptosis by targeting KLF9/p53 axis. [ABSTRACT FROM AUTHOR]

With an poorly characterized pathogenesis, Diabetic encephalopathy (DE), one of the main chronic complications of diabetes, would require further studies. Recent studies have proven that DE developing in conjunction with neuronal apoptosis, which is tightly regulated by a variety of processes and involved with histone acetylation and molecular signaling or so on. Though the histone deacetylase 4 (HDAC4), HDAC5, HDAC7, and HDAC9 form class IIa of the HDAC superfamily have been found participating in multiple neurodegenerative diseases, while JNK signaling pathway activation was hypothesized as a key cause leading to cell apoptosis, the correlation between HDAC4 and JNK signaling pathway remains unknown. Studies have found that Radix Polygoni Multiflori (RPM) contains a variety of ingredients, such as TSG and Emodin, could exert antioxidant effects, scavenge free radicals, inhibit cell apoptosis and provide neuroprotection, but the underlying mechanism has not fully elucidated yet. In the present study, we further explored the mechanism by which RPM improves the cognitive function of diabetic rats. Simultaneously, TSG and Emodin were used to stimulate HT-22 hippocampal neurons treated with high glucose. After RPM extracts or TSG, Emodin treatments, the cognitive functions of DE rats improved while the hippocampal neurons arranged tighter and increased. Meanwhile, the expression level of HAT, HDAC, HDAC4 and JNK signaling pathway and apoptosis related genes were decreased. Our finds indicates that RPM and Emodin would inhibit HDAC4 expression, curb the activation of the JNK pathway, reduce hippocampal neuron apoptosis and ultimately meliorate the cognitive function from diabetes. Additionally, the markedly inhibitory effects of the RPM and Emodin on HAT and HDAC was identified for the first time in this study, which provides a basis for future drug targeting histones acetylation development and application. [Display omitted] • We found that hyperglycemia leads to elevation of HAT and HDAC activity in the hippocampus and that activation of the HDAC4/JNK pathway leads to increased expression of the apoptosis-related proteins Bcl-2, Bax, and Caspase3 and ultimately cognitive decline. • Radix Polygoni Multiflori and Emodin protects against hippocampal neuronal apoptosis by inhibiting the HDAC4/JNK signaling pathway and improves the cognitive function of diabetic rats. • Our study is the first to report that RPM and Emodin have marked inhibitory effects on HAT and HDAC, providing a basis for future drug development and application. [ABSTRACT FROM AUTHOR]