Caspase Family Proteins Research Articles

Pyroptosis: A Novel Therapeutic Target for Bioactive Compounds in Human Disease Treatment? A Narrative Review

Background/Objectives: Bioactive compounds possess the ability to maintain health and improve diseases by regulating inflammation and cell death processes. Pyroptosis is programmed cell death related to inflammation and exerts a critical role in the development and progression of different types of diseases. This narrative review aims to investigate and discuss the effects of dietary bioactive compounds on pyroptosis in different common human pathologies, such as inflammatory disease, bacterial infection, injury disease, cancer, diabetes and heart disease, etc. Method: Studies published in the major databases until December 2024 in English were considered, for a total of 50 papers. Results: The current evidence demonstrated that the bioactive compounds are able to regulate the pyroptosis process by modulating different inflammasome sensors (NLRP1, NLRP3, and AIM2), caspase family proteins (caspase-1, caspase-3, and caspase-11), and gasdermins (GSDMD and GSDME) in many pathological conditions related to inflammation, including cancer and cardiovascular diseases. Conclusions: Bioactive compounds have powerful potential to be the candidate drug for pyroptosis modulation in inflammatory diseases, even if more clinical studies are needed to confirm the effects and establish efficient doses for humans.

Ferulic Acid Regulates GSDMD through the ROS/JNK/Bax Mitochondrial Apoptosis Pathway to Induce Pyroptosis in Lung Cancer.

To improve the prognosis outcome of lung cancer patients, more investigations are still needed. Previous reports have demonstrated the function of Ferulic Acid (FA) in lung cancer; thus, we have attempted to probe more molecular mechanisms underlying FA application in lung cancer. CCK8 and colony formation experiments have been employed to explore cell viability and proliferation. Cell apoptosis was evaluated through flow cytometry. Cell morphology was observed with a microscope. MMP was assessed by JC-1 and LDH activity was evaluated by relative kit. Western blot assays were performed to examine the expression levels of GSDMD, GSDMD-N, caspase family proteins, and ROS/JNK/Bax mitochondrial apoptosis pathway downstream proteins. Flow cytometry analysis also measured the level of ROS. Tissues from animal models were taken for IHC analysis of C-caspase-1. FA was found to inhibit proliferation, change cell morphology, decrease MMP, and enhance LDH activity, suggesting its ability to induce pyroptosis of lung cancer cells. Both caspase-1 and GSDMD were found to be involved in the pyroptosis of lung cancer cells treated with FA, and caspase-1 mediated GSDMD. Moreover, FA was validated to regulate pyroptosis by ROS/JNK/Bax mitochondrial apoptosis pathway in vitro and in vivo. In summary, FA regulates GSDMD through ROS/JNK/Bax mitochondrial apoptosis pathway to induce pyroptosis in lung cancer cells, which may offer a theoretical basis for pyroptosis in the occurrence of lung cancer.

Arecoline induces neurotoxicity in HT22 cells via the promotion of endoplasmic reticulum stress and downregulation of the Nrf2/HO-1 pathway.

Arecoline, the predominant bioactive substance extracted from areca nut (AN), is the world's fourth most frequently used psychoactive material. Research has revealed that chewing AN can affect the central nervous system (CNS) and may lead to neurocognitive deficits that are possibly linked to the action of arecoline. However, the mechanism behind the neurotoxicity caused by arecoline remains unclear. This study aimed to investigate the neurotoxic effects of arecoline and its underlying mechanism. The results showed that arecoline caused cytotoxicity against HT22 cells in a dose-dependent manner and induced apoptosis by upregulating the expression of pro-apoptotic caspase and Bcl-2 family proteins. Furthermore, arecoline escalated intracellular reactive oxygen species (ROS) levels and Ca2+ concentration with increasing doses, thereby motivating endoplasmic reticulum stress (ERS) and ERS-associated apoptotic protein expression. Additionally, the study found that arecoline attenuates intracellular antioxidant defense by inhibiting the translocation of NF-E2-related factor-2 (Nrf2) into the nucleus and decreasing downstream Heme oxygenase-1 (HO-1) levels. The specific inhibitor Sodium 4-phenylbutyrate (4-PBA) can dramatically attenuate arecoline-mediated cell apoptosis and ERS-associated apoptotic pathway expression by blocking ERS. The antioxidant N-Acetylcysteine (NAC) also effectively reverses the arecoline-mediated increase of ERS-related apoptotic pathway protein levels by scavenging intracellular ROS accumulation. In conclusion, this study suggests that arecoline induces neurotoxicity in HT22 cells via ERS mediated by oxidative stress- and Ca2+ disturbance, as well as by downregulation of the Nrf2/HO-1 pathway.

Discovery of novel peptide–dehydroepiandrosterone hybrids inducing endoplasmic reticulum stress with effective in vitro and in vivo anti-melanoma activities

Steroid hybrids have emerged as a type of advantageous compound as they could offer improved pharmacological and pharmaceutical properties. Here, we report a series of novel peptide–dehydroepiandrosterone hybrids, which would effectively induce endoplasmic reticulum stress (ERS) and lead to apoptosis with outstanding in vitro and in vivo anti-melanoma effects. The lead compound IId among various steroids conjugated with peptides and pyridines showed effective in vivo activity in B16 xenograft mice: in medium- and high-dose treatment groups (60 and 80 mg/kg), compound IId would significantly inhibit the growth of tumours by 98%–99% compared to the control group, with the highest survival rate as well. Further mechanism studies showed that compound IId would damage the endoplasmic reticulum and upregulate the ERS markers C/EBP homologous protein (CHOP) and glucose-regulated protein 78 (GRP78), which could further regulate caspase and Bcl-2 family proteins and lead to cell apoptosis. The compound IId was also proven to be effective in inhibiting B16 cell migration and invasion.

Study on the Efficacy and Potential Mechanism of Topical Shen Bai Hair Growing Decoction against Androgenetic Alopecia Based on Ultrahigh Performance Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry and RNA-seq.

Androgenetic alopecia (AGA) is a major problem that can happen to people of all ages, leading to psychological problems, such as anxiety and depression. Topical Shen Bai hair growing decoction (TSBHGD) is based on the pathogenesis of AGA, combined with Traditional Chinese Medicine theory, improved by the Tianjin Academy of Traditional Chinese Medicine Affiliated Hospital according to its clinical treatment experience. This study was designed to demonstrate the therapeutic efficacy of TSBHGD against AGA, analyze the chemical components of TSBHGD as well as the skin-retained and blood-retained components in mice after topical administration of TSBHGD, and clarify the mechanism of its therapeutic efficacy. It was demonstrated that TSBHGD could suppress TNF-α and IL-6 levels and improve pathological phenomena such as hair loss, reduced follicle density, and dermal thickness caused by testosterone solution. Totally 35 components were identified in TSBHGD extracts, 12 skin-retained components were identified in drug-containing skin, and 7 blood-retained components were identified in drug-containing plasma, according to ultrahigh performance liquid chromatography quadrupole time-of-flight mass spectrometry. Transcriptomic sequencing revealed that some of the genes in AGA mice had altered expression patterns, which could be reversed by TSBHGD. Through network pharmacology analysis, it was found that TSBHGD mainly regulated eight signaling pathways, among which the apoptosis signaling pathway ranked first with a significance of 0.00149. Finally, both Bcl-2 and Caspase family proteins in the apoptosis signaling pathway were examined by Western blot. It was confirmed that TSBHGD could inhibit the apoptosis level in AGA mice's skin tissue to exert an anti-AGA effect. This will facilitate the development of new-generation herbal compound formulas with precise efficacy and provide novel ideas for AGA therapy.

Highly sensitive and selective SERS detection of caspase-3 during cell apoptosis based on the target-induced hotspot effect.

Caspase-3 is an important biomarker for the process of apoptosis, which is a key target for cancer treatment. Due to its low concentration in single cells and the structural similarity of caspase family proteins, it is exceedingly challenging to accurately determine the intracellular caspase-3 during apoptosis in situ. Herein, a biosensing strategy based on the target-induced SERS "hot spot" formation has been developed for the simultaneous highly sensitive and selective detection of intracellular caspase-3 level. The nanosensor is composed of gold nanoparticles modified with the probe molecule 4-mercaptophenylboronic acid (4-MPBA) and a peptide chain. The well-designed peptide chain contains two distinct functional domains, one with a sulfhydryl group for bonding to the gold nanoparticles and the other a fragment specifically recognized by caspase-3. When caspase-3 is present, the negatively charged segment (NH2-Asp-Asp-Asp-Glu-Val-Asp-OH) of the peptide chain is specifically hydrolyzed, leaving a positively charged fragment coated on the surface of the gold nanoparticles. At this time, the golden nanoparticles undergo significant coupling aggregation due to the electrostatic interaction, resulting in a large number of SERS "hot spot" formation. The SERS signal of the 4-MPBA located at the nano-gap is significantly boosted because of the local plasma enhancement effect. The highly sensitive determination of caspase-3 can be achieved according to the altered SERS signal intensity of 4-MPBA. The turn-on of the SERS signal-induced target contributes to the excellent selectivity and the formation of the SERS "hot spot" effect that further improves the sensitivity of caspase-3 detection. The advantages of this biosensing technique allow for the precise in situ monitoring of the dynamic changes in caspase-3 levels during apoptosis. In addition, the differences in caspase-3 levels during the apoptosis of various cell types were compared. Monitoring the caspase-3 levels can be used to track the cellular apoptosis process, evaluate the effect of drugs on cancer cells in real time, and provide guidance for the selection of the appropriate drug dosage.

Mechanism of propofol-induced apoptosis in neonatal rat oligodendrocytes

To explore the molecular mechanism of propofol-induced apoptosis in oligodendrocytes. Fortyfive neonatal (7 days old) SD rats were randomized into 3 groups (n=15) for a single intraperitoneal injection of saline (control), long chain fat emulsion, or propofol (50 mg/kg). Eight hours after the injection, the rats were examined for mRNA and protein expressions of caspase-3, caspase-8, and caspase-9 in the brain tissues using qPCR and Western blotting, and the expression levels of nerve growth factor (NGF) mRNA and P-PI3K/P-PAkt were also detected. Compared with those in the control group, the neonatal rats with propofol injection showed significantly up-regulated mRNA and protein expressions of caspase-3, caspase-8, and caspase-9 in the brain tissue (P<0.05) with significantly down-regulated expressions of NGF mRNA and P-PI3K/P-PAkt (P<0.05). Propofol induces apoptosis in oligodendrocytes by activating the caspase family protein members involved in triggering cell apoptosis and inhibiting the anti-apoptosis mechanism.

Enhanced autophagy interacting proteins negatively correlated with the activation of apoptosis-related caspase family proteins after focal ischemic stroke of young rats

BackgroundNeuronal injury induced in young rats by cerebral ischemia reperfusion (CIR) is known to differ substantially from that in adult rats. In the present study, we investigated the specific differences in neuronal injury induced by focal CIR between young and adult rats.Results2, 3, 5-triphenyl tetrazolium chloride (TTC) staining revealed a gradual increase in the infarct volume of both young and adult rats in accordance with I/R times and was significantly lower in young rats than in adult rats under the same conditions. The number of cells in the cortex showing immunoreactivity for neuronal nuclei (NeuN) gradually decreased in both young and adult rats in accordance with I/R times; these numbers were significantly higher in young rats than in adult rats under the same conditions. Similarly, as the duration of I/R increased, the degree of glial activation in the cortex penumbra region became more severe in both young and adult groups; however, glial activation was significantly lower in the cortex penumbra region of young rats when compared with that in adult rats. In addition, the expression of Beclin-1 was significantly higher in the infarct penumbra of young rats than adult rats and was more frequently co-expressed with neurons. The levels of autophagy-related proteins increased significantly in the penumbra region after I/R in both young and adult groups, this increase was more pronounced in young rats than in adult rats. Following CIR, analysis revealed significantly lower levels of pro-apoptosis-related factors and significantly higher levels of anti-apoptosis-related proteins in the young rats than in adult rats.ConclusionsCollectively, the present results suggest that the the reduced levels of neuronal death after CIR in young rats were closely related to enhanced levels of autophagy and reduced levels of pro-apoptosis in neurons.

Serum hsa-circ-0025244 as a biomarker in Chinese occupational mercury-exposed population and mediate apoptosis through JNK/p38 MAPK signaling pathway

BackgroundcircRNAs have been recognized as biomarkers of numerous diseases. We would like to explore the expression pattern and molecular mechanisms of circRNAs in the Chinese occupational mercury-exposed population. MethodsThe workers from a thermometer manufacturing plant and lamp factory in Jiangsu province of China were recruited in 2016. Blood samples were collected from the subjects with chronic mercury poisoning group, mercury absorption group, and the healthy controls. The differentially expressed circRNAs (DECRs) between the three groups were screened from serum samples using a circRNA microarray. The significant DECRs were validated by qRT-PCR, and their respective diagnostic values for mercury poisoning and mercury absorption were analyzed by receiver operating characteristic (ROC) curves. For in vitro experiments, 293T cells were treated with different doses of HgCl2 to determine the half-lethal concentration. The cells were transfected with the siRNA construct or expression plasmid of circRNA. The expression levels of JNK, p38, and caspase family proteins were analyzed by Western blotting. Resultshsa_circ_0025244 was up-regulated in the mercury poisoning and absorption groups compared to the control group (P < 0.05), and positively correlated with the urine mercury levels (P < 0.05). The area under the ROC curve (AUC) of hsa_circ_0025244 for diagnosing occupational mercury poisoning was 0.748, indicating moderate accuracy (P < 0.001). Moreover, the diagnostic accuracy of occupational mercury absorption was high (P < 0.001) with an AUC of 0.918. Knockdown of hsa_circ_0025244 in 293T cells significantly reduced the expression levels of JNK/p38, and caspase family proteins compared to that in the control cells (P < 0.01), and its overexpression led to opposite effects (P < 0.05). Conclusionshsa_circ_0025244 is a potential biomarker for mercury exposure and mediates mercury-induced apoptosis in 293T cells by activating the JNK/p38 MAPK signaling pathway.

Induction of Apoptosis by Metabolites of Rhei Radix et Rhizoma (Da Huang): A Review of the Potential Mechanism in Hepatocellular Carcinoma

Liver cancer is a global disease with a high mortality rate and limited treatment options. Alternations in apoptosis of tumor cells and immune cells have become an important method for detailing the underlying mechanisms of hepatocellular carcinoma (HCC). Bcl-2 family, Caspase family, Fas and other apoptosis-related proteins have also become antagonistic targets of HCC. Da Huang (Rhei Radix et Rhizoma, RR), a traditional Chinese herb, has recently demonstrated antitumor behaviors. Multiple active metabolites of RR, including emodin, rhein, physcion, aloe-emodin, gallic acid, and resveratrol, can successfully induce apoptosis and inhibit HCC. However, the underlying mechanisms of these metabolites inhibiting the occurrence and development of HCC by inducing apoptosis is complicated owing to the multi-target and multi-pathway characteristics of traditional Chinese herbs. Accordingly, this article reviews the pathways of apoptosis, the relationship between HCC and apoptosis, the role and mechanism of apoptosis induced by mitochondrial endoplasmic reticulum pathway and death receptor pathway in HCC and the mechanism of six RR metabolites inhibiting HCC by inducing apoptosis.

Sesamin Acts as Anti-leukemic Compound Interacting with Novel Phosphoprotein Targets and Inducing Apoptosis in Leukemic Cells.

Leukemia is one of the high-incidence cancers that is characterized by an abnormal production of immature white blood cells. Subject to many reports on the side effects of conventional chemotherapy, herbs and natural compounds have been studied as an alternative medicine. In this study, sesamin, a lignan in sesame seed with pharmaceutical functions including anti-cancer, was chosen and treated with MOLT-4 and NB4 leukemic cell lines in various concentrations for 24 and 48 hours. The effect of sesamin on cell inhibition and expression levels of apoptotic genes in leukemic cell lines were investigated by MTT assay and real-time PCR, respectively. Moreover, apoptotic proteins were studied by mass spectrometry and bioinformatics tools to investigate the relation between sesamin and targeted proteins. Results showed that sesamin increased cell inhibition in both cell lines in dose- and time-dependent manner. Levels of caspase-3, -7, -8, and -9 gene expressions significantly increased, while BCL-2 decreased drastically in sesamin-treated cells. From bioinformatics study, PARP4, IPPK and caspase family proteins were found to be involved in sesamin that induced apoptosis in leukemic cells. Besides, doxorubicin, a chemotherapeutic drug, also shared the same protein targets as sesamin in apoptosis pathway. Sesamin demonstrates its potential to enhance cell inhibition and promotes cell apoptosis in both MOLT-4 and NB4 leukemic cell lines. This study will benefit the development of sesamin as an effective anti-leukemia drug in the future.

Anticancer activity study of paeoniflorin Ag(I) complexes against human hepatoma cells 3B cells

A new paeoniflorin Ag(I) complex was synthesized using the hydrothermal method, which was characterized by some spectral techniques like elemental analysis, thermal analysis, 1H nuclear magnetic resonance (1H NMR), Fourier-transform infrared spectroscopy (FTIR), electrospray ionization mass spectrometry (ESI-MS) and geometry optimization. Cell Counting Kit-8 (CCK-8) was used to test the in vitro cytotoxicity of the paeoniflorin Ag(I) complexes in various cells (such as A549, Caco2, HepG2, Hep3B, LO2, H9C2 and PC12 cells). It is shown that the paeoniflorin Ag(I) complexes possessed a remarkable cytotoxicity against the Hep3B cell line, but a low cytotoxicity against the LO2 cell line. Cell cycle progression and membrane potential of Hep3B cells were studied using flow cytometry, and the cell examination of apoptosis was made by Annexin V-FITC/PI staining. Moreover, expressions levels of caspase family proteins and Bcl-2 were also investigated. Our findings demonstrated that the paeoniflorin Ag(I) complexes induced apoptosis of Hep3B cells via the mitochondrial membrane potential access by regulating Bcl-2 and caspase family proteins.

Dietary taurine attenuates hydrogen peroxide-impaired growth performance and meat quality of broilers via modulating redox status and cell death signaling

Oxidative stress seriously affects poultry production. Nutritional manipulations have been effectively used to alleviate the negative effects caused by oxidative stress. This study investigated the attenuating effects and potential mechanisms of dietary taurine on the growth performance and meat quality of broiler chickens challenged with hydrogen peroxide (H2O2). Briefly, a total of 192 male Arbor Acres broilers (28 d old) were randomly categorized into three groups: non-injection of birds on basal diets (control), 10.0% H2O2 injection of birds on basal diets (H2O2), and 10.0% H2O2 injection of birds on basal diets supplemented with 5 g/kg taurine (H2O2 + taurine). Each group consisted of eight cages of eight birds per cage. Results indicated that H2O2 administration significantly reduced growth performance and impaired breast meat quality by decreasing ultimate pH and increasing shear force value (P < 0.05). Dietary taurine improved the body weight gain and feed intake and decreased feed/gain ratio of H2O2-challenged broilers. Meanwhile, oxidative stress induced by intraperitoneal injection of H2O2 suppressed the nuclear factor-κB (NF-κB) signaling and initiated autophagy and apoptosis. Compared with the H2O2 group, taurine supplementation restored the redox status in the breast muscle by decreasing levels of reactive oxygen species and contents of oxidative products and increasing antioxidant capacity (P < 0.05). Moreover, upregulated mRNA expression of NF-κB signaling-related genes, including NF-κB subunit 1 (p50) and B-cell CLL/lymphoma 2 (Bcl-2), and enhanced protein expression of NF-κB were observed in the H2O2 + taurine group (P < 0.05). Additionally, dietary taurine decreased the expression of caspase family, beclin1, and microtubule-associated protein 1light chain 3 beta (LC3-II; P < 0.05), thereby rescuing autophagy and apoptosis in breast muscle induced by H2O2. Collectively, dietary supplementation with taurine effectively improves growth performance and breast meat quality of broilers challenged with H2O2, possibly by protecting against oxidative injury and modulating cell death signaling.

Arsenite induce neurotoxicity of common carp: Involvement of blood brain barrier, apoptosis and autophagy, and subsequently relieved by zinc (Ⅱ) supplementation

Arsenic pollution is a common threat to aquatic ecosystems. The effects of chronic exposure to arsenite on the brains of aquatic organisms are unknown. This study was designed to evaluate arsenic-induced brain damage in common carp (Cyprinus carpio) and the ameliorating effects of divalent zinc ion (Zn2+) supplementation from the aspects of oxidative stress (OxS), tight junction (TJ), apoptosis and autophagy. After arsenite exposure (2.83 mg/L) for 30 days, oxidative damage to the brain was determined, as indicated by inhibited antioxidants system (catalase-superoxide dismutase system, and glutathione system) and elevated levels of biomacromolecule peroxidation (malondialdehyde and 8-hydroxydeoxyguanosine). Moreover, we also found functional damage to the brain as suggested by injuries to the blood-brain barrier (decreases in tight junction) and nerve conduction (depletion of AChE). Mechanisticly, apoptotic and autophagic cell death were indicated by typical morphologies including karyopyknosis and autophagosome, accompanying by key bio-indicators (Bcl-2, caspase and autophagy related gene family proteins). In contrast, the coadministration of Zn2+ (1 mg/L) with arsenite effectively alleviated this damage as suggested by the recovery of the aforementioned bioindicators. This study provides new insight into the brain toxicity caused by arsenite and suggests the application of zinc preparations in the aquatic pollution of arsenic.

Panax quinquefolium saponins protect against cisplatin evoked intestinal injury via ROS-mediated multiple mechanisms

BackgroundCisplatin is one of the most common chemotherapeutic drugs. Cisplatin-induced toxicity gives rise to gastrointestinal cell damage, subsequent diarrhea and vomiting, leading to the discontinuation of its clinical application in long-term cancer chemotherapy. Panax quinquefolium L., also known as American ginseng, has many pharmacological activities such as improving immunity, anti-tumor, anti-radiation and blood sugar lowering. PurposePreviously, our laboratory reported that American ginseng berry extract could alleviate chemotherapeutic agents-induced renal damage caused by cisplatin. Hence, this study further explored the protective effect of P. quinquefolium saponins (PQS) on cisplatin-induced intestinal injury in mice and the possible molecular mechanisms. MethodsBiochemical markers, levels of inflammatory factors, histopathological staining and western blotting were used to analyze intestinal injury based on various molecular mechanisms. ResultsWe demonstrated the destruction of the intestinal barrier caused by cisplatin exposure by detecting the activity of diamine oxidase (DAO) and the expression of tight junction proteins zonula occludens-1 (ZO-1) and occludin. Meanwhile, cisplatin exposure changed SOD and MDA levels in the small intestine, causing oxidative damage to the intestinal mucosa. The inflammation associated-intestinal damage was further explored by the measurement of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and analysis of nuclear factor-kappa B (NF-κB) inflammatory pathway protein expression. Moreover, apoptotic cells labeled with TUNEL staining-positive cells and activated caspase family proteins suggest that cisplatin induces intestinal apoptosis. Interestingly, PQS pretreatment significantly reversed these situations. ConclusionThese evidences clearly suggest that PQS can alleviate cisplatin-induced intestinal damage by inhibiting oxidative stress, reducing the occurrence of inflammation and apoptosis, and improving intestinal barrier function.

Ru(II) Complexes Bearing O, O-Chelated Ligands Induced Apoptosis in A549 Cells through the Mitochondrial Apoptotic Pathway.

Two new Ru(II) complexes containing O, O-chelated ligands, Ru(dip)2(SA) (Ru-1) and Ru(dmp)2(SA) (Ru-2) (dip = 4,7-diphenyl-1,10-phenanthroline; dmp = 2,9-dimethyl-1,10-phenanthroline; SA = salicylate) were synthesized to evaluate their cytotoxicity in vitro. These complexes were found to exhibit moderate antitumor activity to different types of human cancers, including A549 (human lung carcinoma), MCF-7 (breast cancer), HeLa (human cervical cancer), and HepG2 (human hepatocellular carcinoma) cell lines, but displayed low toxicity to human normal cell lines BEAS-2B (immortalized human bronchial epithelial cells) when compared with that of cisplatin. Further studies revealed that these complexes could induce apoptosis in A549 cells, including activating caspase family proteins and poly (ADP-ribose) polymerase (PARP), reducing Bcl-2/Bax and Bcl-xl/Bad ratio, enhancing cellular reactive oxygen species (ROS) accumulation, triggering DNA damage, decreasing mitochondrial membrane potential (MMP), and leading cytochrome c release from mitochondria. Notably, complex Ru-1 showed low toxicity to developing zebrafish embryos. The obtained results suggest that these new synthetic complexes have the potential to be developed as low-toxicity agents for lung cancer treatment.

Ferulic acid isolated from propolis inhibits porcine parvovirus replication potentially through Bid-mediate apoptosis

Propolis from honeybee hives, which is a traditional Chinese medicine, is widely used in veterinary clinics. Many compounds have been identified and isolated from propolis. Ferulic acid (FA), one of the propolis components, previous studies have proven that it has antiviral effects. To study the mechanism of FA antiviral effects, experiments such as immunofluorescence, quantitative real-time PCR and immunoblotting were introduced. In porcine kidney (PK-15) cells, PPV infection induced the expression of the proapoptotic genes Bid, Bad, Bim and Bak, disrupted mitochondrial membrane potential, promoted mitochondria-mediated, caspase-dependent apoptotic signaling and induced apoptosis. Furthermore, the infected PK-15 cells had increased intracellular reactive oxygen species (ROS) generation. FA treatment, however, reversed these effects and increased cell viability. FA treatment also significantly decreased the PPV-induced expression of Bid, Cyt-c and Apaf-1, suggesting that ROS were involved in the activation of the mitochondria-mediated apoptosis pathway. This in vitro study showed that the antiviral activity of FA was probably associated with inhibiting the replication of PPV by blocking proapoptotic factors such as Bid, Bcl-2 and Mcl-1, and attenuating the mitochondria-mediated response by inhibiting the activation of the Bid-related signaling pathway. Pharmacological inhibitors inhibited PPV-induced apoptosis by blocking Bid, and also suppressed the expression of Caspase family proteins in ppv-induced apoptosis. Taken together, our results suggested that PPV induced PK-15 cell apoptosis via activation of Bid and Bid-related signaling pathways and that the mitochondria act as the mediators of these pathways. FA effectively and extensively attenuated this PPV action, and thus is a potential antiviral agent against PPV.

Fucoxanthin inhibits cell proliferation and stimulates apoptosis through downregulation of PI3K/AKT/mTOR signaling pathway in human ovarian cancer cells

Background: Fucoxanthin is rich in seaweed and considered the most efficient anticancer drug because of its powerful antioxidant properties. The aim of this study was to elucidate the role of fucoxanthin on apoptosis via signaling pathway in ovarian cancer cells. First, fucoxanthin exhibited obvious cytotoxicity against A2780 human ovarian cancer cells. Materials and Methods: We established the action potential of fucoxanthin on cell proliferation in addition to apoptosis in A2780 cells, which were measured using reactive oxygen species (ROS) generation and the mitochondrial membrane potential (MMP). Apoptotic-related morphological alterations were inspected by acridine orange/EtBr dual staining. In addition, we analyzed caspase family protein expression by enzyme-linked immunosorbent assay analysis. Results: Our results established that fucoxanthin stimulates apoptosis as confirmed through reduced cell viability, improved production of ROS, and altered MMP in A2780 cells. Further, the fucoxanthin upregulates the expression of caspase (3, 8, and 9) protein experimentally in A2780 cell. In addition, we uncovered upstream signaling cascade (Akt/mTOR) induced by incubation A2780 cell lines with fucoxanthin that mediated cell apoptosis, migration, and invasion process. Conclusion: These findings suggest that fucoxanthin augments apoptosis; reduces cell proliferation, migration, and invasion; and reveals a potential mechanism of fucoxanthin-mediated Akt/mTOR suppression in human ovarian cancer cell line. Hence, fucoxanthin could be reflected as a potential therapeutic agent for ovarian cancer treatment.

Molecular characterization of three caspases from Bostrychus sinensis and their transcriptional responses to bacteria and viruses.

The caspase family proteins are aspartate-specific cysteine proteases that transmit extracellular signals to cells, ultimately cause apoptosis and therefore play a key role in cellular immunity. In this study, we cloned and characterized three caspases from Chinese black sleeper (Bostrychus sinensis), Bscasp-1, Bscasp-8 and Bscasp-9. Real-time PCR analysis showed that Bscasp-1, Bscasp-8 and Bscasp-9 were universally expressed in all tested tissues of B.sinensis. Expression analyses showed that after poly(I:C) stimulation and bacterial (Vibrio parahaemolyticus) infection, the three caspases were significantly upregulated. After poly(I:C) stimulation, the change of Bscasp-1 expression in the head kidney was the most obvious; peak expression was about 80.78-fold more than that of the control. In addition, the expression of Bscasp-8 and Bscasp-9 in the peripheral blood and liver was 167.99- and 17.98-fold higher than that in the control group, respectively. After V.parahaemolyticus infection, the expression peaks of Bscasp-1 and Bscasp-8 in the peripheral blood and spleen were 85.82-fold and 280.83-fold that of the control. However, the expression of Bscasp-9 in the peripheral blood was upregulated only 8.33-fold higher than that in the control group. These results indicate that Bscasp-1, Bscasp-8 and Bscasp-9 are likely involved in response to viral and bacterial infection.

Antitumor Activity of Ohmyungsamycin A through the Regulation of the Skp2-p27 Axis and MCM4 in Human Colorectal Cancer Cells.

Ohmyungsamycin A (1), a novel cyclic peptide discovered from a marine Streptomyces sp., was previously reported with antibacterial and anticancer activities. However, the antitumor activities and the underlying molecular mechanisms of 1 remain to be elucidated. Compound 1 inhibited the proliferation and tumor growth of HCT116 human colorectal cancer cells based on both in vitro cell cultures and an in vivo animal model. A cDNA microarray analysis revealed that 1 downregulated genes involved in cell cycle checkpoint control. Compound 1 also induced G0/G1 cell cycle arrest that was mediated by the regulation of S-phase kinase-associated protein 2 (Skp2)-p27 axis and minichromosome maintenance protein 4 (MCM4). Furthermore, a longer exposure of 1 exhibited an accumulation of a sub-G1 phase cell population, which is characteristic of apoptotic cells. The induction of apoptosis by 1 was also associated with the modulation of caspase family proteins. Compound 1 effectively suppressed tumor growth in a xenograft mouse model subcutaneously implanted with HCT116 cells. In addition, analysis of tumors revealed that 1 upregulated the expression of the CDK inhibitor p27 but downregulated the expression of Skp2 and MCM4. These findings demonstrate the involvement of 1 in cell cycle regulation and the induction of apoptosis in human colorectal cancer cells.