Mitochondria-dependent Apoptotic Pathway Research Articles

Sensitization of Multidrug Resistant Cancer Cells to Doxorubicin Using Ebselen by Disturbing Cellular Redox Status.

Multidrug resistance (MDR) poses a significant problem in cancer treatment, often causing adverse effects during chemotherapy. Ebselen (Ebs), a synthetic organoselenium compound, affects cellular redox status in cancer cells. In the study, we observed that Ebs disrupted cellular redox balance and sensitized drug-resistant cells to doxorubicin (DOX) treatment. The combination of Ebs and DOX led to increased intracellular reactive oxygen species (ROS) levels and lipid peroxidation while decreasing the activity of thioredoxin reductase (TrxR) and cellular antioxidants in drug-resistant cells. Furthermore, this combination treatment demonstrated notable chemosensitizing effects by reducing cell viability and proliferation in MDR cells compared to DOX treatment alone. Additionally, the combination of Ebs and DOX induced DNA fragmentation and exhibited G2/M phase cell cycle arrest. Immunofluorescent analysis revealed that the Ebs and DOX combination upregulated the expression of p53 and p21, which activated the mitochondrial-dependent apoptotic pathway. The combination treatment also enhanced the upregulation of proapoptotic markers such as Bax, Caspase-3, -9, and cytochrome C, while downregulating the expression of the antiapoptotic marker Bcl-2. Therefore, the current discoveries suggest that Ebs could be employed as a drug candidate for reversing MDR in cancer cells by regulating cellular redox homeostasis.

TIN2 modulates FOXO1 mitochondrial shuttling to enhance oxidative stress-induced apoptosis in retinal pigment epithelium under hyperglycemia.

Progressive dysfunction of the retinal pigment epithelium (RPE) and the adjacent photoreceptor cells in the outer retina plays a pivotal role in the pathogenesis of diabetic retinopathy (DR). Here, we observed a marked increase in oxidative stress-induced apoptosis in parallel with higher expression of telomeric protein TIN2 in RPE cells under hyperglycemia in vivo and in vitro. Delving deeper, we confirm that high glucose-induced elevation of mitochondria-localized TIN2 compromises mitochondrial activity and weakens the intrinsic antioxidant defense, thereby leading to the activation of mitochondria-dependent apoptotic pathways. Mechanistically, mitochondrial TIN2 promotes the phosphorylation of FOXO1 and its relocation to the mitochondria. Such translocation of transcription factor FOXO1 not only promotes its binding to the D-loop region of mitochondrial DNA-resulting in the inhibition of mitochondrial respiration-but also hampers its availability to nuclear target DNA, thereby undermining the intrinsic antioxidant defense. Moreover, TIN2 knockdown effectively mitigates oxidative-induced apoptosis in diabetic mouse RPE by preserving mitochondrial homeostasis, which concurrently prevents secondary photoreceptor damage. Our study proposes the potential of TIN2 as a promising molecular target for therapeutic interventions for diabetic retinopathy, which emphasizes the potential significance of telomeric proteins in the regulation of metabolism and mitochondrial function. Created with BioRender ( https://www.biorender.com/ ).

Biological effects and mechanism of β-amyloid aggregation inhibition by penetrable recombinant human HspB5-ACD structural domain protein

Alzheimer's disease (AD) is a global medical challenge. Studies have shown that neurotoxicity caused by pathological aggregation of β-amyloid (Aβ) is an important factor leading to AD. Therefore, inhibiting the pathological aggregation of Aβ is the key to treating AD. The recombinant human HspB5-ACD structural domain protein (AHspB5) prepared by our group in the previous period has been shown to have anti-amyloid aggregation effects, but its inability to penetrate biological membranes has limited its development. In this study, we prepared a recombinant fusion protein (T-AHspB5) of TAT and AHspB5. In vitro experiments showed that T-AHspB5 inhibited the formation of Aβ1–42 protofibrils and had the ability to penetrate the blood-brain barrier; in cellular experiments, T-AHspB5 prevented Aβ1–42-induced oxidative stress damage, apoptosis, and inflammatory responses in neuronal cells, and its mechanism of action was related to microglia activation and mitochondria-dependent apoptotic pathway. In animal experiments, T-AHspB5 improved memory and cognitive dysfunction and inhibited pathological changes of AD in APP/PS1 mice. In conclusion, this paper is expected to reveal the intervention mechanism and biological effect of T-AHspB5 on pathological aggregation of Aβ1–42, provide a new pathway for the treatment of AD, and lay the foundation for the future development and application of T-AHspB5.

Salvia miltiorrhiza polysaccharide mitigates AFB1-induced liver injury in rabbits

Aflatoxin B1 (AFB1) is one of the common dietary contaminants worldwide, which can harm the liver of humans and animals. Salvia miltiorrhiza polysaccharide (SMP) is a natural plant-derived polysaccharide with numerous pharmacological activities, including hepatoprotective properties. The purpose of this study is to explore the intervention effect of SMP on AFB1-induced liver injury and its underlying mechanisms in rabbits. The rabbits were administered AFB1 (25 μg/kg/feed) and or treatment with SMP (300, 600, 900 mg/kg/feed) for 42 days. The results showed that SMP effectively alleviated the negative impact of AFB1 on rabbits' productivity by increasing average daily weight gain (ADG) and feed conversion rate (FCR). SMP reduced aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) levels in serum, ameliorating AFB1-induced hepatic pathological changes. Additionally, SMP enhanced superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) activity, and inhibited reactive oxygen species (ROS), malondialdehyde (MDA), 4-Hydroxynonenal (4-HNE), interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) expression, thus mitigating AFB1-induced oxidative stress and inflammatory responses. Moreover, SMP upregulated the expression of nuclear factor E2 related factor 2 (Nrf2), heme oxygenase 1 (HO-1), NADPH quinone oxidoreductase 1 (NQO1) and B-cell lymphoma 2 (Bcl2) while downregulating kelch like ECH associated protein 1 (Keap1), cytochrome c (cyt.c), caspase9, caspase3, and Bcl-2-associated X protein (Bax) expression, thereby inhibiting AFB1-induced hepatocyte apoptosis. Consequently, our findings conclude that SMP can mitigate AFB1-induced liver damage by activating the Nrf2/HO-1 pathway and inhibiting mitochondria-dependent apoptotic pathway in rabbits.

Effect of NAMPT on the proliferation and apoptosis in odontoblast-like MDPC-23 cell.

This study aimed to evaluate the physiological role of NAMPT associated with MDPC-23 odontoblast cell proliferation. Cell viability was measured using the (DAPI) staining, caspase activation analysis and immunoblotting were performed. Visfatin promoted MDPC-23 odontoblast cell growth in a dose-dependent manner. Furthermore, the up-regulation of Visfatin promoted odontogenic differentiation and accelerated mineralization through an increase in representative odontoblastic biomarkers in MDPC-23 cells. However, FK-866 cell growth in a dose-dependent manner induced nuclear condensation and fragmentation. FK-866-treated cells showed H&E staining and increased apoptosis compared to control cells. The expression of anti-apoptotic factors components of the mitochondria-dependent intrinsic apoptotic pathway significantly decreased following FK-866 treatment. The expression of pro-apoptotic increased upon FK-866 treatment. In addition, FK-866 activated caspase-3 and PARP to induce cell death. In addition, after treating FK-866 for 72 h, the 3/7 activity of MDPC-23 cells increased in a concentration-dependent manner, and the IHC results also confirmed that Caspase-3 increased in a concentration-dependent. Therefore, the presence or absence of NAMPT expression in dentin cells was closely related to cell proliferation and formation of extracellular substrates.

HMGA1 regulates the mitochondrial apoptosis pathway in sepsis-induced cardiomyopathy

High mobility group protein AT-hook 1 (HMGA1), an architectural transcription factor, has previously been reportedto play an essential role in architectural remodeling processes. However, its effects on cardiovascular diseases, particularly sepsis-induced cardiomyopathy, have remained unclear. The study aimed to investigate the role of HMGA1 in lipopolysaccharide-induced cardiomyopathy. Mice subjected to lipopolysaccharide for 12 h resulted in cardiac dysfunction. We used an adeno-associated virus 9 delivery system to achieve cardiac-specific expression of the HMGA1 gene in the mice. H9c2 cardiomyocytes were infected with Ad-HMGA1 to overexpress HMGA1 or transfected with si-HMGA1 to knock down HMGA1. Echocardiography was applied to measure cardiac function. RT-PCR was used to detect the transcriptional level of inflammatory cytokines. CD45 and CD68 immunohistochemical staining were used to detect inflammatory cell infiltration and TUNEL staining to evaluate the cardiomyocyte apoptosis, MitoSox was used to detect mitochondrial reactive oxygen species, JC-1 was used todetect Mitochondrial membrane potential. Our findings revealed that the overexpression of HMGA1 exacerbated myocardial inflammation and apoptosis in response to lipopolysaccharide treatment. Additionally, we also observed that H9c2 cardiomyocytes with HMGA1 overexpression exhibited enhanced inflammation and apoptosis upon stimulation with lipopolysaccharide for 12 h. Conversely, HMGA1 knockdown in H9c2 cardiomyocytes attenuated lipopolysaccharide-induced cardiomyocyte inflammation and apoptosis. Further investigations into the molecular mechanisms underlying these effects showed that HMGA1 promoted lipopolysaccharide-induced mitochondrial-dependent cardiomyocyte apoptosis. The study reveals that HMGA1 worsens myocardial inflammation and apoptosis in response to lipopolysaccharide treatment. Mechanically, HMGA1 exerts its effects by regulating the mitochondria-dependent apoptotic pathway.

Cecropin A Alleviates LPS-Induced Oxidative Stress and Apoptosis of Bovine Endometrial Epithelial Cells.

Dairy cows receiving a prolonged high-concentrate diet express an elevated concentration of lipopolysaccharides (LPSs) in the peripheral blood circulation, accompanied by a series of systemic inflammatory responses; however, the specific impacts of inflammation are yet to be determined. Cecropin-like antimicrobial peptides have become a research hotspot regarding antimicrobial peptides because of their excellent anti-inflammatory activities, and cecropin A is a major member of the cecropin family. To elucidate the mechanism of cecropin A as anti-inflammatory under the condition of sub-acute ruminal acidosis (SARA) in dairy cows, we induced inflammation in bEECs with LPS (10 µg/mL) and then added cecropin A (25 µM). Afterwards, we detected three categories of indexes including oxidative stress indices, inflammation-related genes, and apoptosis-related genes in bovine endometrial epithelial cells (bEECs). The results indicated that cecropin A has the ability to reduce inflammatory factors TNF-α, IL-1β, and IL-8 and inhibit the MAPK pathway to alleviate inflammation. In addition, cecropin A is able to reduce reactive oxygen species (ROS) levels and alleviates LPS-induced oxidative stress and mitochondrial dysfunction by downregulating NADPH Oxidase (NOX), and upregulating catalase (CAT), glutathione peroxidase (GPX), and superoxide dismutase (SOD). Furthermore, cecropin A demonstrates the ability to inhibit apoptosis by suppressing the mitochondrial-dependent apoptotic pathway, specifically Fas/FasL-caspase-8/-3. The observed increase in the Bcl-2/Bax ratio, a known apoptosis regulator, further supports this finding. In conclusion, our study presents novel solutions for addressing inflammatory responses associated with SARA.

Cytotoxicity of bismuth(III) dithiocarbamate derivatives by promoting a mitochondrial-dependent apoptotic pathway and suppressing MCF-7 breast adenocarcinoma cell invasion.

We previously reported that the bismuth(III) dithiocarbamate derivative, bismuth diethyldithiocarbamate (1) exhibited greater cytotoxicity while inducing apoptosis via the intrinsic pathway in MCF-7 cells. We further evaluated the other bismuth(III) dithiocarbamate derivatives, Bi[S2CNR]3, with R = (CH2CH2OH)(iPr), (CH2)4, and (CH2CH2OH)(CH3), denoted as 2, 3, and 4, respectively, in the same MCF-7 cell line. 2-4 were found to exhibit IC50 values of 10.33 ± 0.06µM, 1.07 ± 0.01µM and 25.37 ± 0.12µM, respectively, compared to that of cisplatin at 30.53 ± 0.23µM. Apoptotic promotion via the mitochondrial-dependent pathway was due to the elevation of intracellular reactive oxygen species (ROS), promotion of caspases, release of cytochrome c, fragmentation of DNA, and results of staining assay observed in all compound-treated cells. 2-4 are also capable of suppressing MCF-7 cell invasion and modulate Lys-48 also Lys-63 linked polyubiquitination, leading to proteasomal degradation. Analysis of gene expression via qRT-PCR revealed their modulation, which supported all activities conducted upon treatment with 2-4. Altogether, bismuth dithiocarbamate derivatives, with bismuth(III) as the metal center bound to ligands, isopropyl ethanol, pyrrolidine, and methyl ethanol dithiocarbamate, are potential anti-breast cancer agents that induce apoptosis and suppress metastasis. Further studies using other breast cancer cell lines and in vivo studies are recommended to clarify the anticancer effects of these compounds.

Isolation and purification of Eleutherococcus sessiliflorus (Rupr. & Maxim.) S. Y. Hu peptides and study of their antioxidant effects and mechanisms.

Oxidative stress is a state of imbalance between oxidant and antioxidant effects in the body, which is closely associated with aging and many diseases. Therefore, the development of antioxidants has become urgent. In this study, we isolated three polypeptides, G-6-Y, P-8-R, and F-10-W, from Eleutherococcus sessiliflorus (Rupr. & Maxim.) S. Y. Hu (E. sessiliflorus), based on the antioxidant and anti-aging properties of Eleutherococcus, and screened the most powerful free radical scavenging peptide P-8-R. Ultraviolet B (UVB)-induced oxidative stress damage in the skin was established to test the efficacy of P-8-R. In cellular experiments, P-8-R not only prevented oxidative stress damage in HaCaT cells, reduced intracellular reactive oxygen species levels, and inhibited the overexpression of matrix metalloproteinases but also inhibited apoptosis via the mitochondria-dependent apoptotic pathway; in animal experiments, P-8-R was able to prevent oxidative stress damage in the skin and reduce skin collagen loss by inhibiting the overexpression of MMPs to prevent mouse skin aging. In conclusion, the present study contributes to an in-depth understanding of the active compounds of Eleutherococcus, which is of great significance for the pharmacodynamic mechanism and industrial development of Eleutherococcus, and P-8-R is likely to become a potential antioxidant and anti-aging drug or skin care cosmetic in the future.

Silica nanoparticles induce male reproductive toxicity via Crem hypermethylation mediated spermatocyte apoptosis and sperm flagella damage.

Exposure to silica nanoparticles (SiNPs) could causally contribute to malfunctioning of the spermatogenesis, but the underlying mechanism is rarely known. This study was designed to explore the mechanism of Crem hypermethylation in SiNP-induced reproductive toxicity. The male mice were exposure to SiNPs (0 and 20mg/kg·bw) once every 5days via intratracheal instillation for 35days. After exposure stopped, half of each group was killed, and the rest were sacrificed after another 15-day feeding. GC-2 cells were treated with 0 and 20μg/mL SiNPs. The results showed that SiNPs led to structure damage of spermatocyte and sperm, caused spermatocyte apoptosis, and decreased sperm quantity and quality. After 15days of the withdrawal, the testicular tissue damage gradually recovered. Mechanistic study showed that SiNPs induced hypermethylation of the gene of cAMP responsive element modulator (Crem) in the promoter region. Downregulation of Crem inhibited the expression of outer dense fiber 1 (Odf1), resulting in abnormal sperm flagella structure; at the same time, Crem inhibited the expression of Bcl-xl, causing upregulation of cytochrome-C, cleaved-caspase-9/caspase-9, cleaved-caspase-3/caspase-3, resulting in mitochondrial dependent apoptotic pathway. However, 5-aza, DNA methylation inhibitor, could reverse the SiNP-induced downregulation of Crem and reverse the Crem/Bcl-xl-mediated mitochondrial dependent apoptotic pathway. These results suggested SiNPs could disrupt spermatogenesis by causing Crem hypermethylation to regulate the Odf1 and Bcl-xl in spermatocytes resulting in the sperm flagella structure and spermatocyte apoptosis. Our study provided new insights into the male reproductive toxicity mechanism of SiNPs; Crem demethylation may be a potential way to prevent reproductive dysfunction from SiNP exposure.

Design, synthesis, and antiproliferative screening of new quinoline derivatives bearing a cis-vinyl triamide motif as apoptosis activators and EGFR-TK inhibitors.

In this work, a congeneric set of quinoline-tethered cis-vinyl triamide hybrids was prepared and evaluated as EGFR tyrosine kinase inhibitors for the management of breast cancer. All of the prepared hybrids were evaluated for their antiproliferative effect against the breast MCF-7 cell line. Among the tested hybrids, compound 6f displayed the most potent antiproliferative activity with an IC50 value of 1.87 μM compared to STU (IC50 = 13.71 μM) as the standard reference. The most promising hybrid, 6f, was found to induce cellular cycle arrest at the G1 phase. Furthermore, the molecular mechanism of this hybrid revealed its ability to induce cellular apoptosis via the mitochondrial-dependent apoptotic pathway. Compound 6f decreased MCF-7 cells' MMP compared to the controls (percentage change value of 57.93%). Further investigation of the selective compound 6f showed that it can inhibit EGFR tyrosine kinase.

Electroacupuncture alleviates ciliary muscle cell apoptosis in lens-induced myopic guinea pigs through inhibiting the mitochondrial signaling pathway.

To investigate the effect of electroacupuncture (EA) on the mitochondria-dependent apoptotic signaling pathway in the ciliary muscle of guinea pigs with negative lens-induced myopia (LIM). Guinea pigs were randomly divided into normal control (NC) group, LIM group, LIM+SHAM acupoint (LIM+SHAM) group, and LIM+EA group. Animals in the NC group received no intervention, while those in other three groups were covered with -6.0 diopter (D) lenses on right eyes. Meanwhile, animals in the LIM+EA group received EA at Hegu (LI4) combined with Taiyang (EX-HN5) acupoints, while those in the LIM+SHAM group were treated at sham points. After treatments for 1, 2, and 4wk, morphological changes in ciliary muscles were observed with hematoxylin and eosin (H&E) staining and nick end labeling (TUNEL), and the expression of the mitochondrial apoptotic signaling pathway-related molecules in ciliary muscles was measured by real-time quantitative polymerase chain reaction (qPCR) and Western blot. Additionally, the adenosine triphosphate (ATP) contents were also determined in ciliary muscles. Axial length increased significantly in the LIM and LIM+SHAM groups and decreased in the LIM+EA group. The ciliary muscle fibers were broken and destroyed in both LIM and LIM+SHAM groups, whereas those in the LIM+EA group improved significantly. TUNEL assay showed the number of apoptotic cells increased in the LIM and LIM+SHAM groups, whereas reduced in the LIM+EA group. ATP contents showed a significant decrease in the LIM and LIM+SHAM groups, whereas increased after EA treatment. Compared with the NC group, the dynamin-related protein 1 (DRP1), Caspase3, and apoptotic protease activator 1 (APAF1) levels were significantly increased in the LIM group and decreased in the LIM+EA group. The results provide evidence of EA inhibiting the development of myopia by regulating the mitochondrial apoptotic signaling pathway.

Recombinant human HspB5-ACD structural domain inhibits neurotoxicity by regulating pathological α-Syn aggregation

The treatment of Parkinson's disease is a global medical challenge. α-Synuclein (α-Syn) is the causative protein in Parkinson's disease and is closely linked to its progression. Therefore, inhibiting the pathological aggregation of α-Syn and its neurotoxicity is essential for the treatment of Parkinson's disease. In this study, α-Syn and recombinant human HspB5-ACD structural domain protein (AHspB5) were produced using the BL21(DE3) E. coli prokaryotic expression system, and then the role and mechanism of AHspB5 in inhibiting the pathological aggregation of α-Syn and its neurotoxicity were investigated. As a result, we expressed α-Syn and AHspB5 proteins and characterised the proteins. In vitro experiments showed that AHspB5 could inhibit the formation of α-Syn oligomers and fibrils; in cellular experiments, AHspB5 could prevent α-Syn-induced neuronal cell dysfunction, oxidative stress damage and apoptosis, and its mechanism of action was related to the TH-DA pathway and mitochondria-dependent apoptotic pathway; in animal experiments, AHspB5 could inhibit behavioural abnormalities, oxidative stress damage and loss of dopaminergic neurons. In conclusion, this work is expected to elucidate the mechanism and biological effects of AHspB5 on the pathological aggregation of α-Syn, providing a new pathway for the treatment of Parkinson's disease and laying the foundation for recombinant AHspB5.

Natural products modulate cell apoptosis: a promising way for treating endometrial cancer.

Endometrial cancer (EC) is a prevalent epithelial malignancy in the uterine corpus's endometrium and myometrium. Regulating apoptosis of endometrial cancer cells has been a promising approach for treating EC. Recent in-vitro and in-vivo studies show that numerous extracts and monomers from natural products have pro-apoptotic properties in EC. Therefore, we have reviewed the current studies regarding natural products in modulating the apoptosis of EC cells and summarized their potential mechanisms. The potential signaling pathways include the mitochondria-dependent apoptotic pathway, endoplasmic reticulum stress (ERS) mediated apoptotic pathway, the mitogen-activated protein kinase (MAPK) mediated apoptotic pathway, NF-κB-mediated apoptotic pathway, PI3K/AKT/mTOR mediated apoptotic pathway, the p21-mediated apoptotic pathway, and other reported pathways. This review focuses on the importance of natural products in treating EC and provides a foundation for developing natural products-based anti-EC agents.

Nano-carrier Polyamidoamine Dendrimer G4 Induces Mitochondrialdependent Apoptosis in Human Multidrug-resistant Breast Cancer Cells through G0/G1 Phase Arrest.

Multidrug-resistant tumor cells have special drug detoxification/inactivation mechanisms. The terminal amino groups of the polyamidoamine (PAMAM-NH2), which is cytotoxic to tumor sensitive cells, may have no cytotoxicity in tumor resistant cells with a mechanism different from tumor sensitive cells. This study aimed to investigate the cytotoxic effects of PAMAM-G4-NH2 on human multidrug- resistant breast cancer cells (MCF-7/ADR cells) and identify the possible molecular mechanisms. The cytotoxicity of PAMAM-G4-NH2 (10-1000 μg/mL) against MCF-7 and MCF-7/ADR cells was detected. Then, MCF-7 and MCF-7/ADR cells were treated with PAMAM-G4-NH2 (10, 100 and 1000 μg/mL), and apoptosis, reactive oxygen species (ROS) production, mitochondrial membrane potential (MMP), activities of caspase-3, -8 and -9 and cell cycle distribution were determined. Within 48 h, the cell viabilities in MCF-7/ADR cells after treatment with PAMAM-G4-NH2 were significantly higher than that in MCF-7 cells in the concentration range of 200-500 μg/mL (P < 0.05). Viabilities of MCF-7/ADR cells treated with PAMAM-G4-OH and PAMAM-G4-COOH for 48 and 72 h were much higher than that of MCF-7/ADR cells treated with PAMAM-G4-NH2. Treated with high concentration (1000 μg/mL) of PAMAM-G4-NH2 for 24 h, the apoptosis ratio, ROS levels, as well as caspase-3 and -9 activities in MCF-7 and MCF-7/ADR cells increased, while MMP decreased, and the cells were arrested in the G0/G1 phase. PAMAM-G4-NH2 induced concentration-dependent cytotoxicity in MCF-7/ADR cells via G0/G1 arrest, and acted through h the mitochondria-dependent apoptotic pathway, which was similar to those in tumor sensitive cell, MCF-7 cells. The results suggest that PAMAM-G4-NH2, instead of PAMAM-G4-OH and PAMAM-G4-COOH, can be used as a carrier for drug delivery, concomitantly, it can also induce apoptosis in multidrug-resistant cancer cells in combination with the loaded drug through multiple apoptotic pathways.

Investigation of Molecular Mechanisms Involved in Sensitivity to the Anti-Cancer Activity of Costunolide in Breast Cancer Cells.

Costunolide (CTL), an active compound isolated from Saussurea lappa Clarke and Laurus nobilis L, has been shown to induce apoptosis via reactive oxygen species (ROS) generation in various types of cancer cells. However, details of molecular mechanisms underlying the difference in sensitivity of cancer cells to CTL are still largely unknown. Here, we tested the effect of CTL on the viability of breast cancer cells and found that CTL had a more efficient cytotoxic effect against SK-BR-3 cells than MCF-7 cells. Mechanically, ROS levels were significantly increased upon CTL treatment only in SK-BR-3 cells, which leads to lysosomal membrane permeabilization (LMP) and cathepsin D release, and subsequent activation of the mitochondrial-dependent intrinsic apoptotic pathway by inducing mitochondrial outer membrane permeabilization (MOMP). In contrast, treatment of MCF-7 cells with CTL activated PINK1/Parkin-dependent mitophagy to remove damaged mitochondria, which prevented the elevation of ROS levels, thereby contributing to their reduced sensitivity to CTL. These results suggest that CTL is a potent anti-cancer agent, and its combination with the inhibition of mitophagy could be an effective method for treating breast cancer cells that are less sensitive to CTL.

Neuroregeneration of injured peripheral nerve by fraction B of catfish epidermal secretions through the reversal of the apoptotic pathway and DNA damage.

Introduction: Crush injuries occur from acute traumatic nerve compression resulting in different degrees of neural damage leading to permanent functional deficits. Recently, we have shown that administration of Fraction B (FB) derived from catfish epidermal secretions accelerates healing of damaged nerve in a sciatic nerve crush injury, as it ameliorates the neurobehavioral deficits and enhances axonal regeneration, as well as protects spinal neurons and increases astrocytic activity and decreasing GAP-43 expression. The present study aimed to investigate the role of FB treatment on the apoptotic pathway in the neuroregeneration of the sciatic nerve crush injury. Methods: Male Wistar rats were randomly assigned into five groups: (I) SHAM, (II) CRUSH, (III) CRUSH + (1.5mg/kg) FB, (IV) CRUSH + (3mg/kg) FB, and (V) CRUSH + (4.5mg/kg) FB. Rats underwent sciatic nerve crush surgery, followed by treatment with FB administered intraperitoneally (IP) daily for two weeks and then sacrificed at the end of the fourth week. Results: FB improved the recovery of neurobehavioral functions with a concomitant increase in axonal regeneration and neuroprotective effects on spinal cord neurons following crush injury. Further, FB enhanced Schwann cells (SCs) proliferation with a significant increase in myelin basic protein expression. FB-treated animals demonstrated higher numbers of neurons in the spinal cord, possibly through ameliorating oxidative DNA damage and alleviating the mitochondrial-dependent apoptotic pathway by inhibiting the release of cytochrome c and the activation of caspase-3 in the spinal cord neurons. Conclusion: FB alleviates the neurodegenerative changes in the lumbar spinal cord neurons and recovers the decrease in the neuronal count through its anti-apoptotic and DNA antioxidative properties.

Methanol extract of Pergularia daemia (Forssk.) Chiov. leaves induce apoptosis in triple-negative breast cancer through intrinsic pathway

Most traditional anticancer medications are ineffective in treating triple negative breast cancer (TNBC), which has enhanced resistance to chemotherapeutic agents. Herbs continue to be a key element in the discovery of anticancer medications. In the present study, we assessed the cytotoxicity of methanol extract of leaves of Pergularia daemia (MLPD) in MDA-MB-231 triple-negative breast cancer (TNBC) cell line. The cytotoxicity of MLPD was assessed using MTT assay which revealed significant concentration-dependent cytotoxicity with an IC50 value of 35.95±3.57 µg/mL. Morphological evaluation of MDA-MB-231 cells treated with MLPD showed cytotoxic changes like vacuole formation, altered morphology, and reduction in the number of cells with apoptotic bodies formation. Staining techniques, such as acridine orange and ethidium bromide (AO/EB) showed early apoptosis characterized by yellow-green fluorescence and crescent-shaped nucleus. Hoechst 33258 staining of MDA-MB-231 cells treated with MLPD showed nuclear marginalization indicative of nuclear apoptotic changes. To assess the mitochondrial membrane potential (MMP), we did JC-1 staining and the results revealed green fluorescence indicative of mitochondrial dependent apoptotic pathway. Comet assay confirmed significant DNA damaging property in MDA-MB-231 cells treated with MLPD. Western blotting analysis showed significant downregulation of Bcl-2 by 0.52±0.03 folds with no significant change in caspase-8 expression. Hence, the present study demonstrated that MLPD possessed potent cytotoxic effect against MDA-MB-231 TNBC cells through mitochondria mediated intrinsic pathway of apoptosis.

Design, synthesis, and biological evaluation of tetrahydroisoquinoline stilbene derivatives as potential antitumor candidates.

Herein, a novel class of tetrahydroisoquinoline stilbene derivatives were synthesized, and their potential in vitro anticancer activities were evaluated. Most of the compounds displayed inhibitory activity against one or more representative human cancer cell lines (lung cancer A549 cells, breast cancer MCF-7 cells, and human colorectal carcinoma HT-29 cells), especially compound 16e, which exhibited outstanding cytotoxicity to A549 cells. The tubulin polymerization assay demonstrated that compound 16e displayed better inhibition than colchicine when tested at the same concentration. It was found that 16e arrested A549 cells in G2/M phase by downregulating the expression of cell division cycle 2 (Cdc2) and upregulating the expression of proliferating cell nuclear antigen (PCNA) and cyclin B1. Flow cytometry and Western blot analysis indicated that 16e caused apoptosis via the mitochondrial-dependent apoptotic pathway by reducing mitochondrial membrane potential, inducing ROS accumulation, promoting the release of cytochrome C from the mitochondria into the cytoplasm, and further increasing the protein level of cleaved caspase-3. This work may inspire new ideas for the further improvement of tubulin-related anticancer drugs and treatments.

Isorhamnetin Suppresses Human Gastric Cancer Cell Proliferation through Mitochondria-Dependent Apoptosis.

Derivates of natural products have been wildly utilized in the treatment of malignant tumors. Isorhamnetin (ISO), a most important active ingredient derived from flavonoids, shows great potential in tumor therapy. However, the therapeutic effects of ISO on gastric cancer (GC) remain unclear. Here, we demonstrate that ISO treatment dramatically inhibited the proliferation of two types of GC cells (AGS-1 and HGC-27) both in vitro and in vivo in time- and dose-dependent manners. These results are consistent with the transcriptomic analysis of ISO-treated GC cells, which yielded hundreds of differentially expressed genes that were enriched with cell growth and apoptosis. Mechanically, ISO treatment initiated the activation of caspase-3 cascade and elevated the expression of mitochondria-associated Bax/Bcl-2, cytosolic cytochrome c, followed by the activation of the cleavage of caspase-3 as well as poly ADP-ribose polymerase (PARP), resulting in the severe reduction of the mitochondrial potential and the accumulation of reactive oxygen species (ROS), while pre-treatment of the caspase-3 inhibitor could block the anti-tumor effect. Therefore, these results indicate that ISO treatment induces the apoptosis of GC cells through the mitochondria-dependent apoptotic pathway, providing a potential strategy for clinical GC therapy.