Mitochondria in apoptosis: Bcl-2 family members and mitochondrial dynamics

Photobiomodulation by Near-Infrared 980-nm Wavelengths Regulates Pre-Osteoblast Proliferation and Viability through the PI3K/Akt/Bcl-2 Pathway

BACKGROUND

bone tissue regeneration remains a current challenge. A growing body of evidence shows that mitochondrial dysfunction impairs osteogenesis and that this organelle may be the target for new therapeutic options. Current literature illustrates that red and near-infrared light can affect the key cellular pathways of all life forms through interactions with photoacceptors within the cells' mitochondria. The current study aims to provide an understanding of the mechanisms by which photobiomodulation (PBM) by 900-nm wavelengths can induce in vitro molecular changes in pre-osteoblasts.

METHODS

The PubMed, Scopus, Cochrane, and Scholar databases were used. The manuscripts included in the narrative review were selected according to inclusion and exclusion criteria. The new experimental set-up was based on irradiation with a 980-nm laser and a hand-piece with a standard Gaussian and flat-top beam profile. MC3T3-E1 pre-osteoblasts were irradiated at 0.75, 0.45, and 0.20 W in continuous-wave emission mode for 60 s (spot-size 1 cm²) and allowed to generate a power density of 0.75, 0.45, and 0.20 W/cm² and a fluence of 45, 27, and 12 J/cm², respectively. The frequency of irradiation was once, three times (alternate days), or five times (every day) per week for two consecutive weeks. Differentiation, proliferation, and cell viability and their markers were investigated by immunoblotting, immunolabelling, fluorescein-FragELTM-DNA, Hoechst staining, and metabolic activity assays.

RESULTS AND CONCLUSIONS

The 980-nm wavelength can photobiomodulate the pre-osteoblasts, regulating their metabolic schedule. The cellular signal activated by 45 J/cm², 0.75 W and 0.75 W/cm² consist of the PI3K/Akt/Bcl-2 pathway; differentiation markers were not affected, nor do other parameters seem to stimulate the cells. Our previous and present data consistently support the window effect of 980 nm, which has also been described in extracted mitochondria, through activation of signalling PI3K/Akt/Bcl-2 and cyclin family, while the Wnt and Smads 2/3-β-catenin pathway was induced by 55 J/cm², 0.9 W and 0.9 W/cm².

Assessing Impact of Platinum Complexes on Mitochondrial Functions

Platinum-based antitumor drugs play important roles in the clinical treatment of various tumors. Nevertheless, some deficiencies such as poor targeting ability, low bioavailability, in vivo deactivation, drug resistance, and side effects undermine the efficacy of these drugs. Mitochondria are important organelles which regulate the energy metabolism, physiological function, life span, and survival of the cells. Regulating or interfering with mitochondrial metabolism is of great significance in the prevention or treatment of cancers. Thus, a series of mitochondrion-targeted platinum complexes were prepared by modifying triphenylphosphine (TPP⁺) through chemical modifications, which endow traditional platinum drugs with new properties and mechanisms through interfering with mitochondrial DNA (mtDNA), mitochondrial membrane potential (MMP), mitochondrial morphology, mitochondrial bioenergetics, or production of reactive oxygen species (ROS), thereby opening a new path for the clinical application of platinum drugs. Here we introduce the synthesis of some TPP⁺-modified platinum (II, IV) complexes in details and the detection method of the activity parameters related to the mitochondrial functions.

Mitochondria-targeted cyclometalated rhodium(III) complexes: synthesis, characterization and anticancer research

Over the past few decades, the landscape of inorganic medicinal chemistry has been dominated by investigations on platinum or ruthenium, while the research based on other metal centers such as rhodium has been relatively insufficient. In this work, a series of cyclometalated rhodium(iii) complexes with imidazo[4,5-f][1,10]phenanthroline containing different aromatic rings were synthesized and characterized. Notably, all the complexes displayed stronger anticancer activity against various cancer cells compared with cisplatin. A mechanism study revealed that the rhodium complexes accumulated in the mitochondria, elevated the levels of mitochondrial reactive oxygen species (ROS) and released cytochrome c, indicating severe mitochondrial damage during the anticancer activity. Further studies illustrated that the rhodium complexes caused cell cycle arrest at the G2/M phase, upregulated the expression of p53 and reduced the ratio of B-cell lymphoma-2 (Bcl-2)/Bcl-2-associated x (Bax), which ultimately resulted in cellular apoptosis. Overall, through mitochondrial pathways, these Rh(iii) complexes could induce cellular apoptosis to a larger extent than cisplatin and should be paid close attention as promising chemotherapeutic drugs in anticancer research.

Transcription-Based Multidimensional Regulation of Fatty Acid Metabolism by HIF1α in Renal Tubules

Lipid metabolism plays a basic role in renal physiology, especially in tubules. Hypoxia and hypoxia-induced factor (HIF) activation are common in renal diseases; however, the relationship between HIF and tubular lipid metabolism is poorly understood. Using prolyl hydroxylase inhibitor roxadustat (FG-4592), we verified and further explored the relationship between sustained HIF1α activation and lipid accumulation in cultured tubular cells. A transcriptome and chromatin immunoprecipitation sequencing analysis revealed that HIF1α directly regulates the expression of a number of genes possibly affecting lipid metabolism, including those associated with mitochondrial function. HIF1α activation suppressed fatty acid (FA) mobilization from lipid droplets (LDs) and extracellular FA uptake. Moreover, HIF1α decreased FA oxidation and ATP production. A lipidomics analysis showed that FG-4592 caused strong triglyceride (TG) accumulation and increased some types of phospholipids with polyunsaturated fatty acyl (PUFA) chains, as well as several proinflammatory lipids. Nevertheless, the overall FA level was maintained. Thus, our study indicated that HIF1α reduced the FA supply and utilization and reconstructed the composition of lipids in tubules, which is likely a part of hypoxic adaptation but could also be involved in pathological processes in the kidney.

Dual ATP/reduction-responsive polyplex to achieve the co-delivery of doxorubicin and miR-23b for the cancer treatment

Combination therapy based on the co-delivery of therapeutic genes and anti-cancer drugs has emerged as a promising approach in the cancer treatment, and stimuli-responsive delivery systems could further improve the therapeutic efficacy. Herein, an ATP aptamer and its complementary DNA were used to form Duplex into which doxorubicin (DOX) was loaded to construct DOX-Duplex, and then the lipoic acid-modified oligoethyleneimine (LA-OEI) was employed as a carrier to realize the co-delivery of DOX-Duplex and miR-23b. The ternary nanocomplex LA-OEI/miR-23b/DOX-Duplex showed excellent anti-proliferative effect by inducing the cell apoptosis via mitochondrial signaling pathway and arresting the cell cycle at S phase. Meanwhile, the co-delivery of DOX-Duplex and miR-23b could efficiently inhibit the metastasis of cancer cells by reducing the expression level of MMP-9. The favorable anti-tumor efficacy of ternary nanocomplex was attributed to the rapid drug release in response to intracellular ATP concentration and reduction conditions and the synergistic effect between DOX-Duplex and miR-23b. Thus, ATP aptamer and reduction-responsive polymer provided a convenient platform to construct dual stimuli-responsive systems for the co-delivery of gene and drug in the cancer treatment.

The Use of Chinese Yang/Qi-Invigorating Tonic Botanical Drugs/Herbal Formulations in Ameliorating Chronic Kidney Disease by Enhancing Mitochondrial Function

Background: Chronic kidney disease (CKD) is a leading cause of morbidity and mortality. Mitochondrial dysfunction has been implicated as a key factor in the development of CKD. According to traditional Chinese medicine (TCM) theory, many Chinese Yang/Qi-invigorating botanical drugs/herbal formulations have been shown to produce promising outcomes in the clinical management of CKD. Experimental studies have indicated that the health-promoting action of Yang/Qi invigoration in TCM is related to the up-regulation of mitochondrial energy generation and antioxidant status. Objective: In this review, we aim to test whether Chinese Yang/Qi-invigorating tonic botanical drugs/herbal formulations can provide medical benefits in CKD and its complications. And we also explore the possible involvement of mitochondrial-associated signaling pathway underlying the beneficial effects of Yang/Qi invigoration in TCM. Methods: A systematic search of "PubMed", "China National Knowledge Infrastructure (CNKI)" and "Google Scholar" was carried out to collect all the available articles in English or Chinese related to Chinese Yang/Qi-invigorating tonic botanical drugs/herbal formulations and their effects on mitochondrial function and chronic kidney disease. Result and Discussion: The relationship between the progression of CKD and mitochondrial function is discussed. The effects of Chinese Yang/Qi-invigorating tonic botanical drugs/herbal formulations and their active ingredients, including phytosterols/triterpenes, flavonoids, and dibenzocyclooctadiene lignans, on CKD and related alterations in mitochondrial signaling pathways are also presented in this review. In the future, exploration of the possible beneficial effects and clinical studies of more Yang- and Qi-invigorating botanical drugs/herbal formulations in the prevention and/or/treatment of CKD and the molecular mechanisms relating to the enhancement of mitochondrial functions warrants further investigation. Conclusion: Given the critical role of mitochondrial function in safeguarding renal functional integrity, the enhancement of mitochondrial energy metabolism and antioxidant status in kidney tissue is likely involved in renal protection. Future studies on the biochemical and chemical basis underlying the effects of Chinese Yang/Qi-invigorating tonic botanical drugs/herbal formulations from a mitochondrial perspective will hopefully provide novel insights into the rational development of new drugs for the prevention and/or treatment of CKD.

Design BH3 domain fusion protein as targeting pro-apoptotic self-assembling nanoparticles

Cancer is a serious global health issue, and apoptosis is a logical and practical cancer therapeutic strategy. Apoptosis responses to internal and external signals. Both BH3 domain in the pro-apoptotic proteins and truncated BH3 domain can stimulate cell apoptosis. However, the faults of peptides in systemic administration restrict the applications of truncated BH3 domain. Ferritin, as an attractive nanoparticle with the capacity of self-assemble to unique hollow spherical structure, could display truncated BH3 domain an N-terminal. Thus, in this study, we designed a pro-apoptosis self-assembling protein nanoparticle by BH3 domain fusion at N-terminal of ferritin. We evaluated the size, cytotoxicity and pro-apoptosis effect of these nanoparticles. The results showed that RGD-BH3-HFn, BH3-HFn and HFn had uniformly spherical structure with sizes at 26.08 ± 0.11 nm, 22.07 ± 0.67 nm, and 16.81 ± 0.88 nm, respectively; RGD-BH3-HFn has stronger cytotoxicity against tumor cells than BH3-HFn and HFn. The total apoptosis ratios (including necrosis) of C6 cells induced by RGD-BH3-HFn, BH3-HFn, and HFn proteins were 15.24%, 10.13% and 2.14%, respectively; those of bEnd.3 cells were 15.47%, 7.33% and 1.70%, respectively; while the total apoptosis rate (including necrosis) of MCF-7 cells were 3.24%, 4.9% and - 1.68%, respectively. The results suggested self-assembling RGD-BH3-HFn could target to C6 cells and bEnd.3 cells, and enhance tumor cells apoptosis, its apoptosis effect against C6 cells was 7.11-fold that of HFn, and apoptosis effect against bEnd.3 cells was 9.08-fold that of HFn. These results indicated BH3 domain can be designed as targeting pro-apoptotic nanoparticles.

Cardiac-specific overexpression of miR-122 induces mitochondria-dependent cardiomyocyte apoptosis and promotes heart failure by inhibiting Hand2

MicroRNA-122 (miR-122) is one of several microRNAs elevated in heart failure patients. To investigate the potential role and mechanism of miR-122 in heart failure, we constructed a transgenic mouse overexpressing miR-122 in the heart. This mouse exhibited cardiac dysfunction (as assessed by transthoracic echocardiography), morphological abnormalities of the heart and cardiomyocyte apoptosis characteristic of heart failure. Mechanistically, we identified the Hand2 transcription factor as a direct target of miR-122 using a dual-luciferase reporter assay. In Tg-miR-122 mice and H9C2 cells with miR-122 mimics, we detected apoptosis and increased expression of dynamin-related protein-1 (Drp1). This effect was blocked with prior knockdown of Hand2 in vitro. Our work suggests that miR-122 causes cardiomyocyte apoptosis by inhibiting Hand2 and consequently increasing Drp1-mediated mitochondrial fission. Such a mechanism likely contributes to heart failure and so modulating this pathway could be therapeutically valuable against heart failure.

MicroRNA-2053 involves in the progression of esophageal cancer by targeting KIF3C

This study aimed to explore the role of micorRNA-2053 in esophageal cancer development. The expression level of miR-2053 in esophageal cancer cell lines was detected. After cell transfection, the effects of miR-2053 overexpression on proliferation, apoptosis, migration and invasion of esophageal cancer cells were determined. Moreover, the potential molecular mechanism was explored by measuring the epithelial-mesenchymal transition (EMT) and apoptosis-related proteins. Luciferase reporter assay was conducted to investigate the target gene of miR-2053. The protein expressions of PI3K/AKT pathway associated factors were detected after overexpression of miR-2053 or administration with the pathway inhibitor LY294002. The miR-2053 was downregulated in esophageal cancer cell lines. Overexpression of miR-2053 inhibited cell proliferation, migration and invasion while promoted apoptosis. Molecular mechanism elucidated that miR-2053 could reduce EMT and elevate the expression of pro-apoptotic proteins. Further study found that overexpressed miR-2053 could negatively regulate KIF3C and involve in PI3K/AKT signaling pathway. Our study demonstrated the downregulation of miR-2053 in esophageal cancer. Downregulation of miR-2053 involved in the proliferation, apoptosis, migration and invasion of esophageal cancer cells through upregulating KIF3C expression and activating the PI3K/AKT signaling pathway. miR-2053 may have the potential in clinical treatment of esophageal cancer.

Programmed cell death in stem cell-based therapy: Mechanisms and clinical applications

Stem cell-based therapy raises hopes for a better approach to promoting tissue repair and functional recovery. However, transplanted stem cells show a high death percentage, creating challenges to successful transplantation and prognosis. Thus, it is necessary to investigate the mechanisms underlying stem cell death, such as apoptotic cascade activation, excessive autophagy, inflammatory response, reactive oxygen species, excitotoxicity, and ischemia/hypoxia. Targeting the molecular pathways involved may be an efficient strategy to enhance stem cell viability and maximize transplantation success. Notably, a more complex network of cell death receives more attention than one crucial pathway in determining stem cell fate, highlighting the challenges in exploring mechanisms and therapeutic targets. In this review, we focus on programmed cell death in transplanted stem cells. We also discuss some promising strategies and challenges in promoting survival for further study.

Role of BCL-2 Family Proteins in Apoptosis and its Regulation by Nutrients

In the body, millions of cells die and proliferate each day to maintain normal function and cooperation of all tissues, organs, and systems. Thus, programmed cell death, or apoptosis, is critical to sustain growth, development, and body health. The vital role of B-cell leukemia/lymphoma-2 (BCL-2) family proteins in apoptosis has been identified. The BCL-2 family includes both pro- and antiapoptotic proteins, which are structurally and functionally related, containing up to four BCL-2 homology (BH) motifs (BH1-4). There are also some nutritional factors that regulate apoptosis via the BCL-2 family proteins. In this review, the BCL-2 family proteins and their apoptosis-inducing mechanism have been discussed, along with the nutrient factors that regulate apoptosis through the BCL-2 family proteins.

Epigenetic Remodeling in Obesity-Related Vascular Disease

Significance: The prevalence of obesity and cardiometabolic phenotypes is alarmingly increasing across the globe and is associated with atherosclerotic vascular complications and high mortality. In spite of multifactorial interventions, vascular residual risk remains high in this patient population, suggesting the need for breakthrough therapies. The mechanisms underpinning obesity-related vascular disease remain elusive and represent an intense area of investigation. Recent Advances: Epigenetic modifications-defined as environmentally induced chemical changes of DNA and histones that do not affect DNA sequence-are emerging as a potent modulator of gene transcription in the vasculature and might significantly contribute to the development of obesity-induced endothelial dysfunction. DNA methylation and histone post-translational modifications cooperate to build complex epigenetic signals, altering transcriptional networks that are implicated in redox homeostasis, mitochondrial function, vascular inflammation, and perivascular fat homeostasis in patients with cardiometabolic disturbances. Critical Issues: Deciphering the epigenetic landscape in the vasculature is extremely challenging due to the complexity of epigenetic signals and their function in regulating transcription. An overview of the most important epigenetic pathways is required to identify potential molecular targets to treat or prevent obesity-related endothelial dysfunction and atherosclerotic disease. This would enable the employment of precision medicine approaches in this setting. Future Directions: Current and future research efforts in this field entail a better definition of the vascular epigenome in obese patients as well as the unveiling of novel, cell-specific chromatin-modifying drugs that are able to erase specific epigenetic signals that are responsible for maladaptive transcriptional alterations and vascular dysfunction in obese patients. Antioxid. Redox Signal. 34, 1165-1199.

Amelioration effects of Cirsium japonicum var. maackii extract/fractions on amyloid beta25-35-induced neurotoxicity in SH-SY5Y cells and identification of the main bioactive compound

Amyloid beta (Aβ) is a neurotoxic peptide, and the accumulation of Aβ in the brain is the major characteristic of Alzheimer's disease (AD). Recently, the beneficial effects of Cirsium japonicum var. maackii (CJM) on brain health has attracted much attention. In the present study, we investigated the ability and protective mechanisms of CJM to attenuate neuronal toxicity caused by Aβ using SH-SY5Y cells. Aβ25-35 treatment decreased cell viability, whereas CJM extract/fractions increased cell viability in Aβ25-35-treated cells. We found that CJM treatment prevented the accumulation of reactive oxygen species observed in Aβ25-35-treated control cells. Furthermore, Aβ25-35-mediated production of inflammatory cytokines such as interleukin-1β was significantly suppressed by CJM. In addition, apoptotic factors were modulated in CJM-treated cells by downregulating B-cell lymphoma-2-associated X protein and upregulating B-cell lymphoma-2 protein expression. The assays showed that the ethyl acetate (EtOAc) fraction of CJM has greater neuroprotective bioactivities compared with the other extract/fractions. The main neuroprotective active compound from the EtOAc fraction of CJM was identified as pectolinarin using ultraperformance liquid chromatography-quadrupole time-of-flight-mass spectrometry. Collectively, this study not only describes the neuroprotective effect of CJM against Aβ25-35via the regulation of oxidative, inflammatory, and apoptotic signaling pathways, but also provides useful information for future studies on the mechanism of novel medicinal sources based on pectolinarin isolated from CJM.

Osthole improves pulmonary artery hypertension by inducing apoptosis in pulmonary artery smooth muscle cells

OBJECTIVES

The objectives of this study were to explore the effect of Osthole (Ost) on apoptosis in pulmonary artery smooth muscle cells (PASMCs) and investigate the potential mechanism of this effect.

METHODS

Rats were injected subcutaneously with monocrotaline (MCT) to establish a PAH model, and Ost were intragastrically administrated from day 1 to day 35. After 35 days administration, the mean pulmonary artery pressure and lung weight index were measured. HE and TUNEL staining were used to observe the morphology of pulmonary artery and the apoptosis of PASMCs. In addition, the apoptosis of PASMCs were detected by flow cytometry in cultured PASMCs. The proteins of Bax and Bcl-2, and the levels of p-ASK1 and cleaved caspase 3 were measured by Western blot.

KEY FINDINGS

Ost decreased the mean pulmonary artery pressure and lung weight index in MCT-induced rats, and promoted apoptosis in PASMCs in MCT-induced rats and PDGF-BB stimulated PASMCs. Ost increased the ratio of Bax/Bcl-2 and the levels of p-ASK1, cleaved caspase 3 in MCT-induced rats and PDGF-BB stimulated PASMCs.

CONCLUSION

Ost promoted apoptosis in PASMCs in vivo and in vitro, and the mechanism may be associated with upregulation of ASK1 and the Bax/Bcl-2-caspase 3 signalling pathway.

Chronic stress accelerates the process of gastric precancerous lesions in rats

Background: Gastrointestinal cancers account for 20% of all deaths worldwide. Gastric cancer (GC) patients are susceptible to psychological change, especially depression which is commonly induced by chronic stress. Gastric precancerous lesions (GPL) is an important prodromal stage in the occurrence of gastric cancer. Chronic stress influences the prognosis of GC and may influence the process of GPL as well. Methods: Sixty SD rats were randomly divided into a control group, GPL group, and GPL+CUMS group. In the GPL group, 200μg/mL N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) free drinking method combined with intermittent fasting was applied to establish the GPL animal model. Based on this, we combined the GPL rats with chronic unpredicted mild stress (CUMS) to establish a comprehensive model. We then evaluated their behavior by open field tests and sucrose preference tests. We tested the IL-6, IL-10, TNF-α, Ghrelin, Leptin and Somatostatin (SS) levels in serum and observed the expression of Ghrelin and Gastrokine 2(GKN2) in the gastric mucosa of rats with tumors by immunofluorescence. Results: Our results showed that GPL and GPL+CUMS rats all displayed a significantly decreased total distance and mean velocity traveled in the open field test. The percentages of sucrose preference were significantly decreased in the GPL+CUMS group compared to the control group. In addition, IL-6 and TNF-α were significantly increased in both the GPL and GPL+CUMS groups. Furthermore, the GPL+CUMS group showed significantly increased TNF-α levels in serum compared to the GPL rats. Our results showed that the expression of NF-κB, p53, and BCL-2 were significantly increased while BAX was reduced in the GPL and GPL+CUMS groups. Moreover, Ghrelin and Leptin levels in serum were significantly decreased in the GPL and GPL+CUMS groups. SS levels in serum were significantly increased in the GPL+CUMS group. Additionally, we found that the GPL+CUMS rats with tumors not only had strong expression of GKN2 on the luminal side and the lamina propria of the gastric mucosa and tumor, but also had expression of Ghrelin on the luminal side of the gastric mucosa. The areas that showed strong expression of GKN2 and Ghrelin, are all located around the blood vessels in the tumor. Conclusions: GPL rats under chronic stress would aggravate the conditions of GPL, shorten the process of GPL, and increase the risk of tumorigenesis. In addition, the close monitoring of the mental health of cancer survivors and precancerous lesion patients is suggested to be of great significance in the prevention and treatment of cancer.

Chloroform extract from Sophora Tonkinensis Gagnep. inhibit proliferation, migration, invasion and promote apoptosis of nasopharyngeal carcinoma cells by silencing the PI3K/AKT/mTOR signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Sophora Tonkinensis Gagnep. (STG) has been used as a folk medicine for the treatment of different cancers, especially for nasopharyngeal carcinoma, cervical cancer, liver cancer, stomach cancer, lung cancer and leukemia in China. However, the main chemical composition and anticancer mechanism of chloroform extract of STG (CESTG) were still not very clear.

AIM OF STUDY

This work was carried out to investigate the anticancer effects and mechanisms of chloroform extract of STG (CESTG) on NPC.

METHODS

Cultured NPC CNE1, CNE2 and Np69 cells were treated with CESTG. Cells were subjected to cell proliferation, colony-forming, migration and invasion assays. Cell cycle and apoptosis were measured by flow cytometry. Western blotting and morphological analysis were also performed. Tumor xenografts and drug treatments were made in BALB/c nude mice. The main compounds of CESTG was separated by HPLC.

RESULTS

CESTG inhibited cell viability, clonal growth and induced cell apoptosis in a dose-dependent manner by silencing the PI3K/AKT/mTOR signaling pathway, which is associated with upregulation of cleaved PARP, caspase 3/7/8/9, cleaved caspase 3/7/8/9, Bax and downregulation of PARP, P-PI3K, PI3K, P-AKT, AKT, P-mTOR, mTOR and Bcl-2. In addition, CESTG arrested cell cycle in the G1/S phase, correlating with decreased levels of cyclin D1/B1, CDK 4 and 6. CESTG decreased cell migration and invasion which correlated with decreased expression of β-catenin, vimentin and snail. CESTG significantly inhibited the tumor growth without toxicity.

CONCLUSION

The results presented here suggest that CESTG could be use as a potential source of NPC therapeutic drug.

Down Syndrome Critical Region 1 Reduces Oxidative Stress-Induced Retinal Ganglion Cells Apoptosis via CREB-Bcl-2 Pathway

Purpose

Irreversible retina ganglion cell (RGC) loss is a key process during glaucoma progression. Down syndrome critical region 1 (DSCR1) has been shown to have protective effects against neuronal death. In this study, we aimed to investigate the neuroprotective mechanisms of DSCR1 on RGCs.

Methods

DBA/2J mice and optic nerve crush (ONC) rat model were used for vivo assays. Oxidative stress model of primary RGCs was carried out with in vitro transduction. DSCR1 protein localization was assessed by immunofluorescence. Differential protein expression was validated by Western blot, and gene expression was detected by real-time PCR. TUNEL was used to identify cell apoptosis, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide was used to analyze cell viability.

Results

Significant upregulation of DSCR1 was observed in DBA/2J mice, ONC rat model, and RGCs treated with H₂O₂, reaching peaks at the age of 6 months in DBA/2J mice, 5 days after ONC in rats, and 24 hours after H₂O₂ treatment in RGCs, respectively. DSCR1 was shown to be expressed in the ganglion cell layer. In vitro, overexpressed DSCR1 significantly promoted phosphorylation of cyclic AMP response element binding protein (CREB), B-cell lymphoma 2 (Bcl-2) expression, and RGC survival rate while reducing cleaved caspase 3 expression in H₂O₂-treated RGCs. On the other hand, the opposite effects were shown after knockdown of DSCR1. In addition, silencing of CREB inhibited expression of DSCR1.

Conclusions

Our results suggested that DSCR1 might protect the RGCs against oxidative stress via the CREB–Bcl-2 pathway, which may provide a theoretical basis for future treatments of glaucoma.

The effect of ochratoxin A on cytotoxicity and glucose metabolism in human esophageal epithelium Het-1A cells

Ochratoxin A (OTA) is a widespread mycotoxin worldwide that causes major health risks. The esophageal epithelium is unavoidably exposed to food contaminated OTA after ingestion. Yet, few studies have involved in the putative effects of OTA on the cytotoxicity and glucose metabolism responses on esophageal epithelial cells. In this in vitro study, we aimed to investigate the effects of OTA on esophageal epithelial cell intracellular apoptosis, oxidative stress, DNA damage, mitochondrial function and glucose metabolism. Human esophageal epithelial Het-1A cells were exposed to 2.5, 5 or 10 μM OTA for 24 h. The results showed that OTA decreased cell viability and concomitantly increased apoptosis-related indices, reactive oxygen species generation, oxidative DNA damage, mitochondrial dysfunction and mitochondrial apoptotic pathway activation. In addition, OTA switched the glucose metabolism of Het-1A cells from oxidative phosphorylation towards glycolysis by decreasing the expression of tricarboxylic acid cycle-associated enzymes such as α-ketoglutarate dehydrogenase and isocitrate dehydrogenase 1 and by increasing pyruvate dehydrogenase kinase 1 expression. The data indicated that cell apoptosis, oxidative damage, mitochondrial dysfunction and glucose metabolism perturbation might play pivotal roles in the mechanism of OTA-induced esophageal toxicity.

Cistanche tubulosa Phenylethanoid Glycosides Induce Apoptosis of Hepatocellular Carcinoma Cells by Mitochondria-Dependent and MAPK Pathways and Enhance Antitumor Effect through Combination with Cisplatin

Cistanche tubulosa is a type of Chinese herbal medicine and exerts various biological functions. Previous studies have been demonstrated that Cistanche tubulosa phenylethanoid glycosides (CTPG) exhibit antitumor effects on a variety of tumor cells. However, the antitumor effects of CTPG on HepG2 and BEL-7404 hepatocellular carcinoma (HCC) cells are still elusive. Our study showed that CTPG significantly inhibited the growth of HepG2 and BEL-7404 cells through the induction of cell cycle arrest and apoptosis, which was associated with the activation of MAPK pathways characterized by the up-regulated phosphorylation of p38, JNK, and ERK1/2 and mitochondria-dependent pathway characterized by the reduction of mitochondrial membrane potential. The release of cytochrome c and the cleavage of caspase-3, -7, -9, and PARP were subsequently increased by CTPG treatment. Moreover, CTPG significantly suppressed the migration of HepG2 through reducing the levels of matrix metalloproteinase-2 and vascular endothelial growth factor. Interestingly, CTPG not only enhanced the proliferation of splenocytes but also reduced the apoptosis of splenocytes induced by cisplatin. In H22 tumor mouse model, CTPG combined with cisplatin further inhibited the growth of H22 cells and reduced the side effects of cisplatin. Taken together, CTPG inhibited the growth of HCC through direct antitumor effect and indirect immunoenhancement effect, and improved the antitumor efficacy of cisplatin.

Baking of methionine-choline deficient diet aggravates testis injury in mice

Dietary pattern and cooking methods are important factors to determine the nutrients supplementation for male reproduction. Methionine and choline are two methyl donors in daily diet, which could mediate the lipid metabolism, but their effects on the sperms are not clear. In this study, we fed the mice with methionine-choline deficient (MCD) diet or the baked MCD diet for 6 weeks to evaluate this dietary pattern and the appended high temperature cooking on the spermatogenesis. The results have shown that MCD diet induced testis degradation and the damage of spermatocytes, reduced sperm vitality, motility, but elevated sperm deformity. Additionally, baking of MCD diet aggravated the testis injury, further reduced sperm density, sperm motility, and decreased normal sperm morphology dramatically. These changes were not related to the blood-testis barrier nor the Leydig cells dysfunction, but related to spermatocytes lost and apoptosis. The spermatocyte apoptosis was mediated by reticulum stress, including GRP78, XBP-1 and CHOP gene expression. Our study has shown the importance of methionine and choline in diet, and emphasized the crucial role of cooking condition, which are dietary factors to influence the quality of sperms.

Nicotinic acetylcholine receptors in chemotherapeutic drugs resistance: An emerging targeting candidate

There is no definitive cure for cancer, and most of the current chemotherapy drugs have limited effects due to the development of drug resistance and toxicity at high doses. Therefore, there is an ongoing need for identifying the causes of chemotherapeutic resistance, and it will be possible to develop innovative treatment approaches based on these novel targeting candidates. Cigarette smoking is known to be one of the main causes of resistance to chemotherapeutic agents. Nicotine as a component of cigarette smoke is an exogenous activator of nicotinic acetylcholine receptors (nAChRs). It can inhibit apoptosis, increase cell proliferation and cell survival, reducing the cytotoxic effects of chemotherapy drugs and cause a reduced therapeutic response. Recent studies have demonstrated that nAChRs and their downstream signaling pathways have considerable implications in different cancer's initiation, progression, and chemoresistance. In some previous studies, nAChRs have been targeted to obtain better efficacies for chemotherapeutics. Besides, nAChRs-based therapies have been used in combination with chemotherapy drugs to reduce the side effects. This strategy requires lower doses of chemotherapy drugs compared to the conditions that must be used alone. Here, we discussed the experimental and clinical studies that show the nAChRs involvement in response to chemotherapy agents. Also, controversies relating to the effects of nAChR on chemotherapy-induced apoptosis are in our focus in this review article. Delineating the complex influences of nAChRs would be of great interest in establishing new effective chemotherapy regimens.

Neutron reflectometry and NMR spectroscopy of full-length Bcl-2 protein reveal its membrane localization and conformation

B-cell lymphoma 2 (Bcl-2) proteins are the main regulators of mitochondrial apoptosis. Anti-apoptotic Bcl-2 proteins possess a hydrophobic tail-anchor enabling them to translocate to their target membrane and to shift into an active conformation where they inhibit pro-apoptotic Bcl-2 proteins to ensure cell survival. To address the unknown molecular basis of their cell-protecting functionality, we used intact human Bcl-2 protein natively residing at the mitochondrial outer membrane and applied neutron reflectometry and NMR spectroscopy. Here we show that the active full-length protein is entirely buried into its target membrane except for the regulatory flexible loop domain (FLD), which stretches into the aqueous exterior. The membrane location of Bcl-2 and its conformational state seems to be important for its cell-protecting activity, often infamously upregulated in cancers. Most likely, this situation enables the Bcl-2 protein to sequester pro-apoptotic Bcl-2 proteins at the membrane level while sensing cytosolic regulative signals via its FLD region.

Design, synthesis and antitumor activity evaluation of Chrysamide B derivatives

Marine natural products derived from special or extreme environment provide an important source for the development of anti-tumor drugs due to their special skeletons and functional groups. In this study, based on our previous work on the total synthesis and structure revision of the novel marine natural product Chrysamide B, a group of its derivatives were designed, synthesized, and subsequently of which the anti-cancer activity, structure-activity relationships and cellular mechanism were explored for the first time. Compared with Chrysamide B, better anti-cancer performance of some derivatives against five human cancer cell lines (SGC-7901, MGC-803, HepG2, HCT-116, MCF-7) was observed, especially for compound b-9 on MGC-803 and SGC-7901 cells with the IC ₅₀ values of 7.88 ± 0.81 and 10.08 ± 1.08 μM, respectively. Subsequently, cellular mechanism study suggested that compound b-9 treatment could inhibit the cellular proliferation, reduce the migration and invasion ability of cells, and induce mitochondrial-dependent apoptosis in gastric cancer MGC-803 and SGC-7901 cells. Furthermore, the mitochondrial-dependent apoptosis induced by compound b-9 is related with the JAK2/STAT3/Bcl-2 signaling pathway. To conclude, our results offer a new structure for the discovery of anti-tumor lead compounds from marine natural products.

γ‑irradiated prednisolone promotes apoptosis of liver cancer cells via activation of intrinsic apoptosis signaling pathway

Prednisolone is an anti‑inflammatory drug used to treat a number of conditions, including liver disease and cancer. Numerous studies have demonstrated that glucocorticoids such as prednisolone modified by ionizing radiation can promote anticancer activity in cancer cells. To the best of our knowledge, however, the effect of ionizing radiation on prednisolone structure and cancer cells has not yet been identified. The present study created a novel prednisolone derivative using γ‑irradiation, and its anticancer properties were investigated in liver cancer cells. The present study confirmed the structure of the new prednisolone derivative using liquid chromatogram‑mass spectrometry. MTT assays determined the cytotoxic effects of γ‑irradiated (IR)‑prednisolone in liver cancer cells. Flow cytometry analysis evaluated apoptosis, mitochondrial membrane potential and cell cycle distribution. Western blotting was used to analyze the proteins associated with apoptosis. The chromatogram profile revealed that IR‑prednisolone produced a number of peaks compared with the single peak of the original prednisolone. In contrast to prednisolone, the MTT results showed that IR‑prednisolone significantly prevented the growth of liver cancer cells. IR‑prednisolone promoted apoptosis and arrested the cell cycle at the G0/G1 stage in Huh7 cells. IR‑prednisolone also altered the mitochondrial membrane potential and activated caspase‑associated proteins, which activated the intrinsic apoptotic signaling pathway. In conclusion, IR‑prednisolone promoted anticancer effects in liver cancer cells via apoptosis activation. The present study demonstrated that IR‑prednisolone may be a potential anticancer agent against liver cancer, although specific molecules have yet to be identified.

Progesterone induces apoptosis by activation of caspase-8 and calcitriol via activation of caspase-9 pathways in ovarian and endometrial cancer cells in vitro

Previously we have shown inhibition of endometrial cancer cell growth with progesterone and calcitriol. However, the mechanisms by which the two agents attenuate proliferation have not been well characterized yet. Herein, we investigated how progesterone and calcitriol induce apoptosis in cancer cells. DNA fragmentation was upregulated by progesterone and calcitriol in ovarian and endometrial cancer cells. Time-dependent treatment of ovarian cancer cells, ES-2, and TOV-21G with progesterone enhanced caspase -8 activity after 12 h, whereas OV-90, TOV-112D, HEC-1A, and HEC-59 cells showed increased activity after 24 h. Caspase 9 activity was increased in all cell lines after 24 h treatment with calcitriol. Pretreatment of cancer cells with a caspase-8 inhibitor (z-IETD-fmk) or caspase-9 inhibitor (Z-LEHD-fmk) significantly attenuated progesterone and calcitriol induced caspase-8 and caspase-9 expression, respectively. The expression of FasL, Fas, FAD, and pro-caspase-8, which constitute the death-inducing signaling complex (DISC), was upregulated in progesterone treated cancer cells. Knockdown of FAS or FADD with specific siRNAs significantly blocked progesterone-induced caspase-8. Cleavage of the BID was not affected by caspase-8 activation suggesting the absence of cross-talk between caspase-8 and caspase-9 pathways. Calcitriol treatment decreased mitochondrial membrane potential and increased the release of cancer cytochrome C. These findings indicate that progesterone induces apoptosis through activation of caspase-8 and calcitriol through caspase-9 activation in cancer cells. A combination of progesterone-calcitriol activates both extrinsic and intrinsic apoptotic pathways in cancer cells.

Mitochondrial outer membrane permeabilization at the single molecule level

Apoptotic cell death is essential for development, immune function or tissue homeostasis, and its mis-regulation is linked to various diseases. Mitochondrial outer membrane permeabilization (MOMP) is a central event in the intrinsic apoptotic pathway and essential to control the execution of cell death. Here we review current concepts in regulation of MOMP focusing on the interaction network of the Bcl-2 family proteins as well as further regulatory elements influencing MOMP. As MOMP is a complex spatially and temporally controlled process, we point out the importance of single-molecule techniques to unveil processes which would be masked by ensemble measurements. We report key single-molecule studies applied to decipher the composition, assembly mechanism and structure of protein complexes involved in MOMP regulation.

The molecular mechanism of a novel derivative of BTO-956 induced apoptosis in human myelomonocytic lymphoma cells

Acute myeloid leukemia (AML) is a malignant cancer of the hematopoietic system. Although the effectiveness of arsenic compounds has been recognized and applied clinically, some patients are still found resistant to this chemotherapy. In this study, we investigated that a synthetic thyroid hormone analog (TA), 2-iodo-4-nitro-1-(o-tolyloxy) benzene, had a strong apoptosis effect on U937 cells. U937 cells were treated with TA, and examinted the generation of reactive oxygen species (ROS), dysfunction of mitochondria, expression of pro-apoptosis and anti-apoptosis, and cleavage of caspase-3 and Poly (ADP-ribose) polymerase (PARP). Further, it is also evaluated that insight molecular mechanism and signaling pathways involved in the study. It is found that TA significantly induced apoptosis in U937 cells through production of ROS, dysfunction of mitochondria, and activation of caspase cascade. It was also observed that MAPK signaling pathway including ERK, JNK, and P38 signals are involved in the induction of apoptosis. Moreover, marked activation of autophagy and ER stress markers such as LC3, P62, Beclin1 and GRP78, CHOP were observed, respectively. Pretreatment with ER stress inhibitor tauroursodeoxycholic acid (TUDCA) and autophagy inhibitor 3-Methyladenine (3-MA) have successfully attenuated and aggravated TA-induced apoptosis, respectively. We further confirmed the active involvement of ER stress and autophagy signals. In conclusion, TA induced apoptosis through ER stress and activation of autophagy, and the latter is not conducive to TA-induced cell death. Our results may provide a new insight into the strategic development of novel therapy for the treatment of AML.

Mechanisms of mitochondrial cell death

Mitochondria are double-membrane bound organelles that not only provide energy for intracellular metabolism, but also play a key role in the regulation of cell death. Mitochondrial outer membrane permeabilization (MOMP), allowing the release of intermembrane space proteins like cytochrome c, is considered a point of no return in apoptosis. MOMP is controlled by the proteins of the B-cell lymphoma 2 (BCL-2) family, including pro-and anti-apoptotic members, whose balance determines the decision between cell death and survival. Other factors such as membrane lipid environment, membrane dynamics, and inter-organelle communications are also known to influence this process. MOMP and apoptosis have been acknowledged as immunologically silent. Remarkably, a growing body of evidence indicates that MOMP can engage in various pro-inflammatory signaling functions. In this mini-review, we discuss about our current knowledge on the mechanisms of mitochondrial apoptosis, as well as the involvement of mitochondria in other kinds of programmed cell death pathways.

DRP1 Promotes BRAFV600E-Driven Tumor Progression and Metabolic Reprogramming in Colorectal Cancer

Background

Mitochondria are highly dynamic organelles which remain in a continuous state of fission/ fusion dynamics to meet the metabolic needs of a cell. However, this fission/fusion dynamism has been reported to be dysregulated in most cancers. Such enhanced mitochondrial fission is demonstrated to be positively regulated by some activating oncogenic mutations; such as those of KRAS (Kristen rat sarcoma viral oncogene homologue) or BRAF (B- rapidly accelerated fibrosarcoma), thereby increasing tumor progression/ chemotherapeutic resistance and metabolic deregulation. However, the underlying mechanism(s) are still not clear, thus highlighting the need to further explore possible mechanism(s) of intervention. We sought to investigate how BRAF^V600E driven CRC (colorectal cancer) progression is linked to mitochondrial fission/fusion dynamics and whether this window could be exploited to target CRC progression.

Methods

Western blotting was employed to study the differences in expression levels of key proteins regulating mitochondrial dynamics, which was further confirmed by confocal microscopy imaging of mitochondria in endogenously expressing BRAF^WT and BRAF^V600E CRC cells. Proliferation assays, soft agar clonogenic assays, glucose uptake/lactate production, ATP/ NADPH measurement assays were employed to study the extent of carcinogenesis and metabolic reprograming in BRAF^V600E CRC cells. Genetic knockdown (shRNA/ siRNA) and/or pharmacologic inhibition of Dynamin related protein1/Pyruvate dehydrogenase kinase1 (DRP1/PDK1) and/or BRAF^V600E were employed to study the involvement and possible mechanism of these proteins in BRAF^V600E driven CRC. Statistical analyses were carried out using Graph Pad Prism v 5.0, data was analyzed by unpaired t-test and two-way ANOVA with appropriate post hoc tests.

Results

Our results demonstrate that BRAF^V600E CRC cells have higher protein levels of mitochondrial fission factor- DRP1/pDRP1^S616 leading to a more fragmented mitochondrial state compared to those harboring BRAF^WT . This fragmented mitochondrial state was found to confer glycolytic phenotype, clonogenic potential and metastatic advantage to cells harboring BRAF^V600E . Interestingly, such fragmented mitochondrial state seemed positively regulated by mitochondrial PDK1 as observed through pharmacologic as well as genetic inhibition of PDK1.

Conclusion

In conclusion, our data suggest that BRAF^V600E driven colorectal cancers have fragmented mitochondria which confers glycolytic phenotype and growth advantage to these tumors, and such phenotype is dependent at least in part on PDK1- thus highlighting a potential therapeutic target.

BCL2L13: physiological and pathological meanings

BCL2L13 is a BCL2-like protein. It has been discovered for two decades, now on the way to be a hotspot of research with its physiological and pathological meanings found in recent years. Start with the pro-apoptotic activity, there have been reported consecutively that BCL2L13 could also induce mitochondrial fragmentation, inhibit cell death and promote mitophagy. Similar to BNIP3, BCL2L13 cannot be indiscriminately categorized into pro- or anti-apoptotic proteins. It anchors in the mitochondrial outer membrane, and expresses in various cells and tissues. This article reviews for the first time that BCL2L13 functions in physiological processes, such as growth and development and energy metabolism, and its dysregulation participating in pathological processes, including cancer, bacterial infection, cardiovascular diseases and degenerative diseases, suggesting its important roles in these events.

Wogonoside promotes apoptosis and ER stress in human gastric cancer cells by regulating the IRE1α pathway

Gastric cancer is a disease that occurs in the digestive system of humans and remains a problem in the medical field. Wogonoside, a natural flavonoid, has been reported to exert antitumor effects on various types of tumors. However, the effects of wogonoside on gastric cancer remain elusive. The aim of the present study was to detect whether wogonoside treatment could induce apoptosis and ER stress in gastric cancer cells. In the present study, CCK-8 assay was used to detect the cell viability, Annexin V/PI staining was used to detect the cells apoptosis, western blot analysis and real-time PCR analysis was used to detect the endoplasmic reticulum (ER) stress in the AGS and MKN-45 gastric cancer cell lines. Wogonoside treatment reduced the viability of AGS and MKN-45 cells and induced apoptosis. Furthermore, the expression level of caspase-3 and -9 significantly increased following wogonoside treatment compared with that in non-treated cells, and the protein expression levels of proapoptotic Bax and antiapoptotic Bcl-2 increased and decreased, respectively compared with that in the control group. In addition, the phosphorylated protein expression levels of mitogen-activated protein kinase kinase 5 (ASK1) and JNK increased following wogonoside treatment, and the protein expression levels of tumor necrosis factor receptor-associated factor 2 (TRAF2) and serine/threonine-protein kinase/endoribonuclease IRE1 (IRE1α) were also increased following treatment with 50 µM wogonoside for 48 h. Furthermore, the interactions between IRE1α, TRAF2 and ASK1 significantly increased following wogonoside treatment, suggesting that wogonoside induced endoplasmic reticulum (ER) stress in the AGS and MKN-45 cell lines. In addition, small interfering RNA-mediated silencing of IRE1α suppressed the activity of the IRE1α-TRAF2-ASK1 complex and prevented wogonoside-induced cell apoptosis. In conclusion, the results of the present study suggested that wogonoside exhibited antitumor activity by inducing ER stress-associated cell death through the IRE1α-TRAF2-ASK1 pathway.

Mitochondrial targeted rhodium(III) complexes: Synthesis, characterized and antitumor mechanism investigation

Recently, rhodium complexes have received intensive attentions due to their tunable chemical and biological properties as well as attractive antitumor activity. In this work, two imidazole triphenylamino rhodium complexes [Rh(ppy)₂L1]PF6 (Rh1) and [Rh(ppy)₂L2]PF6 (Rh2) (ppy = 2-phenylpyridine, L1 = 4-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)-N,N-diphenylaniline, L2 = N-(4-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)phenyl)-4-methyl-N-(p-tolyl)aniline) have been synthesized and characterized. Both complexes display stronger anticancer activity against a various of cancer cells than cisplatin and they can effectively localize to mitochondria. Further mechanism studies show that Rh1 induce caspase-dependent apoptosis through mitochondrial damage, down-regulate the expression of B-cell lymphoma-2 (Bcl-2)/Bcl2-associated x (Bax) and reactive oxygen species (ROS) elevation. Our work provides a strategy for the construction of highly effective anticancer agents targeting mitochondrial metabolism through rational modification of rhodium complexes.

Novel Oxovanadium Complex VO(hntdtsc)(NPIP): Anticancer Activity and Mechanism of Action on HeLa Cells

Oxovanadium complexes, particularly vanadyl (IV) derivatives with hybrid ligands of Schiff base and polypyridyl, have been demonstrated to possess great anticancerous therapeutic efficacy. However, most of the studies on the activity of these oxovanadium complexes have mainly focused on in vitro studies, and animal studies in vivo are extremely scarce. Based on the antitumor test results of four novel oxovanadium complexes in our previous work, this work further conducted a comprehensive antitumor activity study in vitro and in vivo on VO(hntdtsc)(NPIP), which owned the strongest inhibitory activity in vitro on multiple tumor cell proliferation. The cellular mechanism study suggested that VO(hntdtsc)(NPIP) inhibited the cell proliferation via arresting the cell cycle at G0/G1 phase through the p16-cyclin D1-CDK4-p-Rb pathway and inducing cell apoptosis through mitochondrial-dependent apoptosis pathway on HeLa cells. Inconsistent with the effects in vitro, VO(hntdtsc)(NPIP) significantly inhibited the growth of tumor and induced the apoptosis of cancer cells in mice xenograft models according to the results of nude mice in vivo image detection, H&E pathological examination, and immunohistochemical detection of p16/Ki-67 protein expression. Collectively, all the results, particularly studies in vivo, demonstrated that VO(hntdtsc)(NPIP) hold a potential to be the lead compound and further to be an anticervical cancer drug.

Green Synthesis of Silver Nanoparticles Using Annona muricata Extract as an Inducer of Apoptosis in Cancer Cells and Inhibitor for NLRP3 Inflammasome via Enhanced Autophagy

Annona muricata is one of the most important traditional medicinal plants which contains numerous chemicals that exhibit various pharmacological properties. In this study, silver nanoparticles were prepared using A. muricata peel extract as a reducing agent and the effect was enhanced through A. muricata like pharmaceutical activity. AgNPs formation was confirmed by color changes, UV-visible spectroscopy, SEM, DLS, and XRD. The anti-proliferative activity of AgNPs against THP-1, AMJ-13, and HBL cell lines was studied. Apoptotic markers were tested using AO/EtBr staining assay, cell cycle phases using flowcytometry, and the expression of P53. Autophagy takes an essential part in controlling inflammasome activation by primary bone marrow-derived macrophages (BMDMs). We report novel functions for AgNPs-affected autophagy, represented by the control of the release of IL-1β, caspase-1, adaptor protein apoptosis-associated speck-like protein containing a CARD (ASC), and NLRP3 in BMDMs following treatment with LPS+ATP. The current study revealed that the AgNPs inhibited THP-1 and AMJ-13 cell proliferation. Meanwhile, the AgNPs significantly increased autophagy and reduced IL-1b and NLRP3 levels in both in vivo and in vitro models. The secretion of IL-1β was reduced whereas the degradation of NLRP3 inflammasome was enhanced. These findings propose that AgNPs apply an anti-proliferative activity against THP-1 and AMJ-13 cells through the stimulation of apoptosis via mitochondrial damage and induction of p53 protein pathway. In addition, AgNP-induced autophagy reduced the levels of IL-1β and NLRP3 inflammasome activation. This indicated that the AgNPs augment autophagy controlled by the IL-1β pathway via two different novel mechanisms. The first one is regulating activation of the IL-1 β, caspae-1, and ASC, while the second is NLRP3 targeting for lysosomal degradation. Overall, this study suggests that AgNPs could be a potent therapy for various types of cancer and an alternative treatment for preventing inflammation via enhancing autophagy.

Chlorpromazine, an antipsychotic agent, induces G2/M phase arrest and apoptosis via regulation of the PI3K/AKT/mTOR-mediated autophagy pathways in human oral cancer

Chlorpromazine (CPZ), an FDA-approved phenothiazine derivative used to treat schizophrenia and other psychiatric disorders, has been demonstrated to have potential anti-tumor effects. However, the potential effects of CPZ on human oral cancer cells and the underlying molecular mechanisms remain unknown. In this study, treatment of human oral cancer cells with CPZ inhibited their proliferation and induced G2/M phase arrest. Treatment with CPZ induced apoptosis through the extrinsic death receptor and the intrinsic mitochondrial pathways. In addition, the induction of autophagy was observed by the formation of autophagosomes, the expression of autophagy-related proteins and activation of the PI3K/Akt/mTOR/p70S6K pathway. The CPZ-induced cell death was reversed by the pan-caspase inhibitor Z-VAD-FMK, by the autophagy inhibitor 3-MA and by the knockdown of LC3B using a shRNA (shLC3B), suggesting that autophagy promoted CPZ-induced apoptosis. Finally, CPZ significantly suppressed tumor growth in both a zebrafish oral cancer xenotransplantation model and in a murine model of 4-nitroquinoline-1-oxide (4NQO)-induced oral cancer. Overall, this evidence demonstrated that CPZ is a novel promising strategy for the treatment of oral cancer.

Mitochondrial control of cellular protein homeostasis

Mitochondria are involved in several vital functions of the eukaryotic cell. The majority of mitochondrial proteins are coded by nuclear DNA. Constant import of proteins from the cytosol is a prerequisite for the efficient functioning of the organelle. The protein import into mitochondria is mediated by diverse import pathways and is continuously under watch by quality control systems. However, it is often challenged by both internal and external factors, such as oxidative stress or energy shortage. The impaired protein import and biogenesis leads to the accumulation of mitochondrial precursor proteins in the cytosol and activates several stress response pathways. These defense mechanisms engage a network of processes involving transcription, translation, and protein clearance to restore cellular protein homeostasis. In this review, we provide a comprehensive analysis of various factors and processes contributing to mitochondrial stress caused by protein biogenesis failure and summarize the recovery mechanisms employed by the cell.

Polygoni Multiflori Radix Preparat Delays Skin Aging by Inducing Mitophagy

Background

As the skin is the largest organ of the human body, it is aging inevitably and produces cosmetic and psychological problems, and even disease. Therefore, the molecular mechanisms related to the prevention of skin aging need to be further explored.

Methods

Aging models were constructed by D-galactose. Mice were administrated with polygoni multiflori radix preparat (PMRP), PMRP and 3-methyladenine, or PMRP and rapamycin intragastrically. The apparent and viscera index of aged rats was measured. Then, the physicochemical property, antioxidant ability, histological structure, mitochondrial membrane potential, ATP and ROS levels, and mitophagy of aged skins were determined. Finally, the expression of PINK1, Parkin, P62, and LC3II/I; apoptosis-related proteins; and the percentage of apoptotic cells were measured.

Results

PMRP relieved skin aging with reducing of thymus index, improvement of pathological damage and histological structure, increase of the expression area of fibrous tissue, the ratio of type I to type III collagen, and antioxidant ability of aged skins. Importantly, PMRP also improved mitochondrial dysfunction with an increase in the content of mitochondrial membrane potential and ATP and a decrease of ROS levels. Moreover, mitophagy was enhanced with the treatment of PMRP when observed using electron microscopy, and the expression of PINK1, Parkin, and LC3I/II was increased with PMRP treatment but P62 expression was decreased. Meanwhile, PMRP alleviated apoptosis with a decrease of apoptotic cell and the expression of Cleaved-cas3, Bax, Cyt-c, AIF, and Smac as well as an increase of Bcl-2 expression.

Conclusion

The results demonstrated that the polygoni multiflori radix preparata may delay skin aging by inducing mitophagy.

LPS Preconditioning Attenuates Apoptosis Mechanism by Inhibiting NF-κB and Caspase-3 Activity: TLR4 Pre-activation in the Signaling Pathway of LPS-Induced Neuroprotection

Neuroinflammation, an inflammatory response within the nervous system, has been shown to be implicated in the progression of various neurodegenerative diseases. Recent in vivo studies showed that lipopolysaccharide (LPS) preconditioning provides neuroprotection by activating Toll-like receptor 4 (TLR4), one of the members for pattern recognition receptor (PRR) family that play critical role in host response to tissue injury, infection, and inflammation. Pre-exposure to low dose of LPS could confer a protective state against cellular apoptosis following subsequent stimulation with LPS at higher concentration, suggesting a role for TLR4 pre-activation in the signaling pathway of LPS-induced neuroprotection. However, the precise molecular mechanism associated with this protective effect is not well understood. In this article, we provide an overall review of the current state of our knowledge about LPS preconditioning in attenuating apoptosis mechanism and conferring neuroprotection via TLR4 signaling pathway.

Chemical compounds with a neuroprotective effect from the seeds of Celosia argentea L

Oxidative stress plays a central role in the common pathophysiology of neurodegenerative diseases such as Alzheimer's disease, amyotrophic lateral sclerosis, and Parkinson's disease. Antioxidant therapy has been suggested for the prevention and treatment of neurodegenerative diseases. Compounds derived from natural sources may offer the potential for new treatment options. Semen Celosiae is a traditional Chinese edible herbal medicine with a long history in China and exhibits wide-reaching biological activities such as hepatoprotective, anti-tumor, anti-diarrheal, anti-diabetic, anti-oxidant, etc. In this study, nine saponins and two phenylacetonitrile glycosides were isolated from Semen Celosiae and their structures were identified using ESI-MS and NMR techniques. Among them, compounds 1 and 2 have not been previously reported. The total concentrations of the five triterpenoid saponins and the two phenylacetonitrile glycosides were 3.348 mg g^-1 and 0.187 mg g^-1, respectively, suggesting that Semen Celosiae is a novel viable source of the two kinds of compounds. These compounds were observed to significantly attenuate t-BHP-induced neuronal damage by effectively enhancing cell viability and decreasing reactive oxygen species generation and cell apoptosis rate in NSC-34 cells. Furthermore, compounds 1 and 7 reduced the ratios of cleaved caspase-3: caspase-3 and cleaved caspase-7: caspase-7 and the level of cytochrome C, while they increased the levels of SOD1 and Beclin 1. These findings suggest that compounds 1-11 are potent inhibitors of neuron injury elicited by t-BHP, possibly via inhibition of oxidative stress and apoptosis, and activation of autophagy; therefore they may be valuable leads for future therapeutic development.

Mitochondrial Dysfunction and Diabetic Nephropathy: Nontraditional Therapeutic Opportunities

Diabetic nephropathy (DN) is a progressive microvascular diabetic complication. Growing evidence shows that persistent mitochondrial dysfunction contributes to the progression of renal diseases, including DN, as it alters mitochondrial homeostasis and, in turn, affects normal kidney function. Pharmacological regulation of mitochondrial networking is a promising therapeutic strategy for preventing and restoring renal function in DN. In this review, we have surveyed recent advances in elucidating the mitochondrial networking and signaling pathways in physiological and pathological contexts. Additionally, we have considered the contributions of nontraditional therapy that ameliorate mitochondrial dysfunction and discussed their molecular mechanism, highlighting the potential value of nontraditional therapies, such as herbal medicine and lifestyle interventions, in therapeutic interventions for DN. The generation of new insights using mitochondrial networking will facilitate further investigations on nontraditional therapies for DN.

p53-dependent apoptosis is essential for the antitumor effect of paclitaxel response to DNA damage in papillary thyroid carcinoma

A functional p53 protein plays an important role in killing tumor cells. Previous studies showed that chemotherapeutic drug, paclitaxel (PTX), showed anti-tumor activity through inducing G2/M arrest and apoptosis by targeting microtubules in tumor cells. However, PTX was not sensitive to p53-inactivated papillary thyroid carcinoma (PTC) cells by inducing G2/M arrest only. Recombinant adenovirus-p53 (rAd-p53) was used to increase the level of p53, which significantly increased the sensitivity of PTC cells to PTX by inducing S arrest, G2/M arrest and apoptosis. To discuss the anti-tumor mechanism of rAd-p53 + PTX and found p53 activation was necessary for anti-tumor effect of PTX in PTC cells. There was high level of p53 in rAd-p53-treated PTC cells. rAd-p53 + PTX increased the level of p21, p-ATM and γ-H2AX and decreased the level of Cyclin D1/E1, suggesting p53 activated p21 which negatively regulated cyclins to induce S arrest response to DNA damage in PTC cells. rAd-p53 + PTX increased the levels of cleaved-PARP-1, cleaved -Caspase 3, and BAX and decreased the level of BCL-XL, suggesting p53 regulates the expression of BAX/BCL-XL to mediate DNA damage-induced apoptosis in PTC cells. Furthermore, rAd-p53 + PTX showed significant tumor inhibition in TPC-1 xenograft model, with an inhibitory rate of 79.39%. TUNEL assay showed rAd-p53 + PTX induced notable apoptosis in tumor tissues. rAd-p53 showed good sensitization of PTX in vitro and in vivo through inducing DNA damage induced-apoptosis indicated p53-dependent apoptosis was essential for the antitumor effect of PTX in PTC.

Acylated Ghrelin Administration Inhibits Sleeve Gastrectomy-Induced Hippocampal Oxidative Stress, Apoptosis and Tau-Hyperphosphorylation by Activating the PI3K/Akt Pathway

This study investigated the impact of exogenous replacement therapy with acylated ghrelin (AG) post sleeve gastrectomy (SG) on the memory function in rats. In addition, we investigated the possible underlying mechanisms, including the effects on markers of oxidative stress, tau phosphorylation, and apoptosis. Adult male Wistar rats were divided into four groups (N = 18/group) as follows: sham (control), SG, SG+AG (100 μM), and SG+AG+LY294002 (0.25 μg/100 g). We continued all treatments daily for four weeks post-surgery. SG impaired the spatial, retention, and recognition memories as tested by the Morris water maze test, passive avoidance test, and novel object recognition test, respectively. Also, it enhanced the levels of reactive oxygen species and lipid peroxides, reduced glutathione and protein levels of Bcl-2, and increased the levels of Bax and cleaved caspase-3 in the hippocampus. In addition, SG reduced the hippocampal levels of acetylcholine and brain-derived neurotrophic factor. Concomitantly, it inhibited the hippocampal activity of Akt and increased the activity of glycogen synthase kinase 3β and tau protein phosphorylation. Exogenous administration of acylated ghrelin to rats that had undergone SG prevented memory deficits. Also, it prevented the alteration in the above-mentioned biochemical parameters, an effect that was abolished by co-administration of LY294002 (phosphoinositide 3-kinase inhibitor). In conclusion, AG replacement therapy after SG in rats protects them against memory deficits and hippocampal damage by suppressing tau protein phosphorylation, mediated by activating PI3K/Aktinduced inhibition of glycogen synthase kinase 3β.

Roles of mitochondria in the hallmarks of metastasis

Although mitochondrial contributions to cancer have been recognised for approximately a century, given that mitochondrial DNA (mtDNA) is dwarfed by the size of the nuclear genome (nDNA), nuclear genetics has represented a focal point in cancer biology, often at the expense of mtDNA and mitochondria. However, genomic sequencing and advances in in vivo models underscore the importance of mtDNA and mitochondria in cancer and metastasis. In this review, we explore the roles of mitochondria in the four defined 'hallmarks of metastasis': motility and invasion, microenvironment modulation, plasticity and colonisation. Biochemical processes within the mitochondria of both cancer cells and the stromal cells with which they interact are critical for each metastatic hallmark. We unravel complex dynamics in mitochondrial contributions to cancer, which are context-dependent and capable of either promoting metastasis or being leveraged to prevent it at various points of the metastatic cascade. Ultimately, mitochondrial contributions to cancer and metastasis are rooted in the capacity of these organelles to tune metabolic and genetic responses to dynamic microenvironmental cues.

[6]-Gingerol impedes 7,12-dimethylbenz(a)anthracene-induced inflammation and cell proliferation-associated hamster buccal pouch carcinogenesis through modulating Nrf2 signaling events

The present study examines the chemopreventive role of [6]-gingerol, an active component of ginger, on 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis models. The HBP has been developed with an addition of 0.5% of DMBA to the HBP area three times per week, up to the end of the 16th experimental week. At the end of the experiment, we noticed 100% tumor incidence and precancerous lesions, such as dysplasia, hyperplasia, keratosis, and well-differentiated squamous cell carcinoma, in DMBA-induced HBP. Furthermore, we observed that [6]-gingerol inhibited the increased thiobarbituric acid-reactive substances and decreased antioxidant levels in DMBA-induced hamsters. Moreover, [6]-gingerol inhibits DMBA-exposed over expression of inflammatory markers (inducible nitric oxide synthase, interleukin [IL]-1β, IL-6, cyclooxygenase-2, and tumor necrosis factor-α) and cell proliferation markers (cyclin D1, proliferating cell nuclear antigen); induces proapoptotic markers in HBP. Nuclear factor erythroid-2-related factor-2 (Nrf2) is a major antioxidant transcription factor, which regulates the antioxidant gene-dependent scavenge of tumor proliferation and apoptosis. Overexpression of Nrf2 signaling plays a pivotal role and can be a novel target in preventing carcinogenesis. In this study, [6]-gingerol restores the DMBA-induced depletion of Nrf2 signaling and thereby prevents buccal pouch carcinogenesis in hamsters. These results point out that [6]-gingerol impedes the responses of inflammatory and cell proliferation-associated progression of cancer through the action of Nrf2 signaling.

In Vitro Bioassay-Guided Identification of Anticancer Properties from Moringa oleifera Lam. Leaf against the MDA-MB-231 Cell Line

Moringa oleifera Lam. (MO) is a medicinal plant distributed across the Middle East, Asia, and Africa. MO has been used in the traditional treatment of various diseases including cancer. This study aimed to perform bioassay-guided fractionation and identification of bioactive compounds from MO leaf against MDA-MB-231 breast cancer cells. MO leaf was sequentially extracted with hexane, ethyl acetate (EtOAc), and ethanol. The most effective extract was subjected to fractionation. MO extract and its derived fractions were continuously screened for anti-cancer activities. The strongest fraction was selected for re-fractionation and identification of bioactive compounds using LC-ESI-QTOF-MS/MS analysis. The best anticancer activities were related to the fraction no. 7-derived crude EtOAc extract. This fraction significantly reduced cell viability and clonogenic growth and increased cells apoptosis. Moreover, sub-fraction no. 7.7-derived fraction no. 7 was selected for the identification of bioactive compounds. There were 10 candidate compounds tentatively identified by LC-ESI-QTOF-MS. Three of identified compounds (7-octenoic acid, oleamide, and 1-phenyl-2-pentanol) showed anticancer activities by inducing cell cycle arrest and triggering apoptosis through suppressed Bcl-2 expression which subsequently promotes activation of caspase 3, indicators for the apoptosis pathway. This study identified 10 candidate compounds that may have potential in the field of anticancer substances.