Background/Objectives: Doxorubicin (DOX) is an effective chemotherapeutic agent, but its clinical use is limited by dose-dependent cardiotoxicity. Emerging evidence suggests that epigenetic dysregulation, particularly altered DNA methylation, contributes to DOX-induced cardiac injury. Metformin has been reported to exert cardiometabolic and epigenetic regulatory effects. This study investigated genome-wide DNA methylation changes induced by chronic metformin exposure and their effects on doxorubicin sensitivity in H9c2 cardiomyoblast cells. Methods: Genome-wide DNA methylation changes induced by chronic metformin exposure were investigated in H9c2 cardiomyoblast cells using whole-genome bisulfite sequencing (WGBS). Cells were treated with metformin (0.7-2.8 mM) for four months prior to DOX exposure. Cellular sensitivity to DOX was evaluated using MTT-based dose-response analysis and IC50 estimation. Results: DOX reduced cell viability (IC50 = 0.164 µM). Chronic metformin pre-treatment produced a dose-dependent rightward shift in DOX dose-response curves, increasing IC50 values to 0.21, 0.289, and 0.51 µM at 0.7, 1.4, and 2.8 mM metformin, respectively. WGBS revealed distinct separation between treatment groups in principal component analysis. Significant methylation changes (adjusted p-value < 0.05) were identified in genes related to oxidative stress, mitochondrial function, apoptosis, and chromatin regulation. Conclusions: Chronic metformin exposure induces dose-dependent genome-wide DNA methylation remodeling in cardiac cells and is associated with altered cellular sensitivity to doxorubicin. These findings suggest that metabolic modulation by metformin may influence epigenetic regulation and cellular stress responses relevant to chemotherapy-induced cardiotoxicity.
Background: Hypoxia, a hallmark of solid tumors, results from inadequate oxygen supply as tumors grow, leading to a cascade of cellular adaptations that enhance malignancy and therapeutic resistance. The research primarily investigates the hypoxia-induced gene expression changes in breast CSCs and evaluates the effects of these changes on tumor angiogenesis and metastasis. Objective: To characterize the changes in gene expression of hypoxia and angiogenesis pathways in both hypoxic CSCs and HUVEC cells exposed to the hypoxic CSCs conditioned medium, and to evaluate the effect of secreted factors by CSCs in the media on the angiogenic capability of Human umbilical vein endothelial cells (HUVEC). Methods: Chemo-resistance to doxorubicin was assessed using 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) cell proliferation assay. Real-time quantitative polymerase chain reaction (qRT-PCR) assay was performed to assess gene expression pattern in hypoxia pathway in CSCs. Furthermore, the study explored the interaction between hypoxic CSCs and human umbilical vein endothelial cells (HUVEC), through assessing the expression of angiogenic pathway genes and Capillarylike tube structure formation assay in HUVECs exposed to hypoxic CSCs-conditioned medium. Results: Flow cytometric identification of CD44+/CD24- cells showed that that the sorted MCF7-CSCs acquired stemness character much higher than their parental cells, and declines over time. Hypoxia significantly increased the resistance of CSCs to doxorubicin, with a maximum of 4.78 folds enhancement after 22 episodes of 8-h hypoxia compared to normal MCF7 in 2D cultures. Gene expression analysis of hypoxic CSCs revealed significant changes in 14 genes of the hypoxic pathway. The expressions of 5 of these genes were significantly up-regulated, while those of 9 genes were significantly down-regulated (p < 0.05). Gene expression analysis of HUVECs treated with conditioned media collected from hypoxic CSCs revealed significant changes in 31 genes of Angiogenic pathway genes. The expressions of 5 of these genes were significantly up-regulated, while those of 26 genes were significantly down-regulated (p < 0.05). Conclusion: These findings underscore the critical impact of hypoxia on breast cancer progression through modulation of CSC characteristics and angiogenic responses. This study paves the way for the development of novel therapeutic approaches that could inhibit tumor progression and overcome resistance to existing treatments.
Pancreatic cancer is currently one of the least curable types of human cancer and remains a key health problem. One of the most important characteristics of pancreatic cancer is its ability to grow under hypoxic conditions. Hypoxia is associated with resistance of cancer cells to radiotherapy and chemotherapy. It is a major contributor to pancreatic cancer genetic instability, which local and systemic resistance that may result in poor clinical outcome. Accordingly, identifying gene expression changes in cancer resistance genes that occur under hypoxic conditions may identify a new therapeutic target. The aim of the present study was to explore the association between hypoxia and resistance to chemotherapy and determine the alteration in the expression of cancer resistance-related genes in the presence of hypoxia. Pancreatic cancer cells (PANC-1) were exposed to 8 h hypoxic episodes (<1% oxygen) three times/week for a total of 20 episodes (chronic hypoxia) or 72 h hypoxic episodes twice/week for a total of 10 episodes (acute hypoxia). The alterations in gene expression were examined using reverse transcription-quantitative PCR array compared with normoxic cells. Chemoresistance of hypoxic cells toward doxorubicin was assessed using MTT cell proliferation assay. Both chronic and acute hypoxia induced chemoresistance toward doxorubicin in PANC-1 pancreatic cancer cell line. The greatest changes occurred in estrogen Receptor Alpha Gene (ESR1) and ETS Like-1 protein (ELK1) pathways, in nucleic transcription factor Peroxisome proliferator-activated receptors (PPARs) and in a cell cycle inhibitor cyclin dependent kinase inhibitor 1A (CDKN1A). The present study demonstrated that exposing cells to prolonged hypoxia results in different gene expression changes involving pleotropic pathways that serve a role in inducing resistance in pancreatic cancer.
BackgroundHypoxia plays a critical role in the tumor microenvironment by affecting cellular proliferation, metabolism, apoptosis, DNA repair, and chemoresistance. Since hypoxia provokes a distinct shift of microRNA, it is important to illustrate the relative contribution of each hypoxamiR to cancer progression. AimsThe present study aims to shed light on the hypoxamiRs that are involved in pancreatic and breast cancer progression to highlight novel targets for the development of new therapies. MethodsFor 20 cycles, MCF7 breast cancer cells and PANC-1 pancreatic cancer cells were subjected to chronic cyclic hypoxia, which consisted of 72 hours of hypoxia followed by 24 hours of reoxygenation. After 10 and 20 cycles of hypoxia, miRNA expression alterations were profiled using RT-PCR array and further analyzed using a visual analytics platform. The MTT cell proliferation assay was used to determine hypoxic cells' chemoresistance to doxorubicin. ResultsUnder chronic cyclic hypoxia, hypoxic PANC-1 cells have a comparable doubling time with their normoxic counterparts, whereas hypoxic MCF7 cells show a massive increase in doubling time when compared to their normoxic counterparts. Both hypoxic cell lines developed EMT-like phenotypes as well as doxorubicin resistance. According to the findings of miRNet, 6 and 10 miRNAs were shown to play an important role in enriching six hallmarks of pancreatic cancer in the 10th and 20th cycles of hypoxia, respectively, while 7 and 11 miRNAs were shown to play an important role in enriching the four hallmarks of breast cancer in the 10th and 20th cycles of hypoxia, respectively. ConclusionsmiR-221, miR-21, miR-155, and miR-34 were found to be involved in the potentiation of hypoxic PANC-1 hallmarks at both the 10th and 20th cycles, while miR-93, miR-20a, miR-15, and miR-17 were found to be involved in the potentiation of hypoxic MCF7 hallmarks at both the 10th and 20th cycles. This variation in miRNA expression was also connected to the emergence of an EMT-like phenotype, alterations in proliferation rates, and doxorubicin resistance. The chemosensitivity results revealed that chronic cyclic hypoxia is critical in the formation of chemoresistant phenotypes in pancreatic and breast cancer cells. miR-181a and let-7e expression disparities in PANC1, as well as miR-93, miR-34, and miR-27 expression disparities in MCF7, may be associated with the formation of chemoresistant MCF7 and PANC-1 cells following 20 cycles of chronic cyclic hypoxia. Indeed, further research is needed since the particular mechanisms that govern these processes are unknown.
Background Psychosocial stress (STS) is a common stress in modern societies. Chronic STS is associated with the impairment of a broad range of cognitive functions in humans and with prolonged abnormalities in memory. Matrix metalloproteinases (MMPs), a protein family of zinc-containing endopeptidases, are essential in neuro-inflammation and involved in neurodegenerative diseases. L-Car possessed neuroprotective, antioxidant, and anti-inflammatory properties and was shown to modulate MMPs. Objective The current study aimed to examine the protective effect of L-Carnitine (L-CAR) on STS-induced changes in serum corticosterone levels, MMP-2, -9, and -12 protein and mRNA expression in the hippocampus as a possible mechanism for L-CAR protective effect on STS-induced memory impairment. Methods The chronic STS and L-CAR (300 mg/kg/day, i.p) were simultaneously administered for 6 weeks to adult male Wistar rats. Serum corticosterone and protein levels of MMP-2, -9 and -12 were evaluated using ELISA. Real-Time PCR techniques were used to determine the mRNA levels of MMP-2, -9 and -12 in the hippocampus. Results The findings showed that serum corticosterone levels and MMP-2 and -9 protein levels were significantly increased (p<0.05) in the STS group compared to the control. Similarly, RT-PCR findings showed that the mRNA of those proteinases significantly increased (p<0.05) following the intruder method. On the other hand, the administration of L-CAR restored the alterations in corticosterone levels and MMPs gene and protein expression induced by chronic STS. Conclusion STS induced elevations in corticosterone and MMP-2 and -9 levels in the hippocampus. L-CAR, on the other hand, exhibited protective effects against the STS-induced changes in MMP-2 and -9.
ABSTRACT Mesenchymal stem cells (MSCs) are used as novel therapeutic tools in cell-based therapies including diabetic complications. However, diabetes may negatively affect the therapeutic potential of autologous MSCs. In order to enhance the utilization of diabetic MSCs, better characterization of their angiogenic capacity should be performed. The aim of this study was to investigate the effect of diabetes mellitus (DM) on the angiogenic potential of bone marrow derived MSCs. MSCs were isolated from DM subjects and were compared with MSCs isolated from non-DM subjects. The angiogenic potential of MSCs was assessed in which there was insignificant difference in the proliferation and expression of angiogenic factors between the two groups. Moreover, no statistically significant change was found in the viability and angiogenic activities of endothelial cells isolated from both groups. Results indicate that the hyperglycemic milieu had no significant impact on the angiogenic-related functional properties of MSCs and they are able to survive the harsh diabetic conditions.
Background:P2 receptors have been implicated in the release of neurotransmitter and pro-inflammatory cytokines due to their response to neuro-excitatory substances in the microglia. The P2X4, P2X7 and P2Y12 receptors are involved in the development of pain behavior induced by peripheral nerve injury. However, it is not known if blocking P2X4, P2X7 and P2Y12 receptors is associated with the expression and the release of interleukin-1B (IL-1β), interleukin-6 (IL-6), or tumor necrosis factor-α (TNF-α) in cultured neonatal spinal cord microglia.Objective:For this reason, we examined the effects of P2X4, P2X7 and P2Y12 antagonists on the expression and the release of IL-1β, IL-6, and TNF-α in ATP-stimulated microglia.Methods:In this study, we observed the effect of A-740003, PSB-12062 and MRS 2395 (P2X4, P2X7 and P2Y12 receptors antagonist, respectively), on the expression and release of IL-1β, IL-6 and TNF-α by using real-time fluorescence quantitative polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA).Results:ATP induced the increased expression of IL-1β, IL-6 and TNF-α at the level of messenger RNA (mRNA). ATP-evoked increase in IL-1β, IL-6 and TNF-α mRNA expression was inhibited by the P2X4 receptor antagonist A-740003 or P2X7 receptor antagonist PSB-12062, respectively. Similarly, ATP-evoked release of IL-1β, IL-6 and TNF-α was inhibited by A-740003 and PSB-12062. Furthermore, ATP-evoked increased expression of Iba-1, IL-1β, IL-6 and TNF-α mRNA, and release of IL-1β, IL-6 and TNF-α were nearly all blocked after co-administration of A-740003 plus PSB-12062. Finally, ATP-evoked increased gene expression and release of IL-1β, IL-6 and TNF-α were also inhibited by MRS 2395 (P2Y12 antagonist).Conclusion:These observations suggest a new clue for therapeutic strategies to treat the neuro-inflammation.
Background: Mercurialis annua has been traditionally used by native people for its diuretic, laxative, antiemetic and antioxidant activity in addition to its usefulness in the treatment of warts, eye problems and microbial infections. Aim: The goal of this work is to study the different extracts of aerial parts of Mercurialis annua collected from the Jordan territories and test them for possible antioxidant, cytotoxic and antiangiogenic activities. Materials and Methods: One kilogram of the dried powdered aerial parts of M. annua, was extracted by maceration with n-hexane, ethyl acetate, and ethanol (96%), respectively. Flavonoids were detected and identified by UV spectrophotometer, TLC, NMR, Mass, and melting point in comparison with the standard. The brine-Shrimp cytotoxicity /Lethality test was performed to measure the LC50 for all M. annua extracts, using Colchicine and chloroform as positive control and negative control, respectively. Both the ethanolic extract and ethyl acetate extract of M. annua were tested for DPPH radical scavenging activity (antioxidant activity). The ethanol extract was evaluated for possible antiproliferative activities against human leukemia (K562), breast cancer (MCF-7), cervical cancer (Hela), lung cancer (A562), and fibroblast cell lines. All the three extracts from M. annua were also evaluated for possible antiangiogenic activity using the ex vivo Rat Aortic assay. Results: The ethanolic extract has shown mild cytotoxic activity, especially on the MCF-7 breast cell lines as compared to ethyl acetate and hexane extract. In addition, the ethanolic extract resulted in the highest radical scavenging activity (61.3% inhibition), while all extracts have shown negligible antiangiogenic activities. Conclusion: The study shows that the ethanolic extract of Mercurialis annua from Jordan could serve as a possible source for developing anticancer and antioxidant drugs in the future.
The development of plant-based nano-materials is considered an eco-friendly technology because it does not involve hazardous chemicals. In this study, bimetallic ZnFe2 O4 and CrFe2 O4 nanoparticles were synthesized using an aqueous extract of Boswellia carteri resin. Synthesized ZnFe2 O4 and CrFe2 O4 nanoparticles were characterized by UV-Vis spectroscopy, FTIR, XRD, and HR-TEM. The anti-inflammatory activity was investigated in LPS-stimulated RAW 264.7 macrophages, whereas antioxidant activity was examined using a Hydrogen Peroxide Scavenging Activity Assay, Nitric Oxide Scavenging Activity Assay, and ABTS Radical Scavenging Assay. ZnFe2 O4 and CrFe2 O4 nanoparticles demonstrated a moderate scavenger of H2 O2 with IC50 values; 87.528 ± 8 μg/ml and 146.4468 ± 12 μg/ml, respectively. While they exhibited a strong scavenger of NO with IC50 values; 4.01 ± 0.7 μg/ml and 4.01 ± 0.7μg/ml, respectively. Interestingly, ZnFe2 O4 and CrFe2 O4 nanoparticles revealed an excellent anti-inflammatory activity by dose-dependently suppressing mRNA expressions of IL-1b, IL-6, and TNF-α. Also, ZnFe2 O4 and CrFe2 O4 nanoparticles suppress the protein expression of TNF-α. Together, our results proved that phyto-mediated ZnFe2 O4 and CrFe2 O4 nanoparticles using Boswellia carteri resin have great potential in biomedical applications such as anti-inflammatory and antioxidant. PRACTICAL APPLICATIONS: Our phyto-synthesized chromium iron oxide bimetallic nanoparticles (NPs) have shown a novel and potent anti-inflammatory activity, with remarkable biosafety toward tested macrophages. Zinc iron oxide bimetallic NPs exhibited anti-inflammatory effect with a lesser extent compared to the former, with moderate cytotoxicity against tested macrophages. Both zinc and chromium iron oxide NPs exhibited an equivalent antioxidant activity. Our resin-capped chromium iron oxide NPs are suggested to be a competing nonsteroidal anti-inflammatory agent; it is further recommended to establish advanced animal studies to confirm their biosafety, stability, and anti-inflammatory activity accompanied with the antioxidant activity.
OBJECTIVE Achillea fragrantissima L. (Asteraceae) is a traditionally used medicinal herb in the rural communities of Jordan. METHODS The present study evaluated the efficacy of the ethanol extract of this species on angiogenesis in both, ex vivo using rat aortic ring assay and in vivo using rat excision wound model. RESULTS In concentrations of 50 and 100 µg/ml, the ethanol extract showed angiogenic stimulatory effect and significantly increased length of capillary protrusions around aorta rings of about 60% in comparison to those of untreated aorta rings. In MCF-7 cells, the ethanol extract of A. fragrantissima stimulates the production of VEGF in a dose-dependent manner. 1% and 5% of ethanol extract of A. fragrantissima containing vaseline based ointment was applied on rat excision wounds for six days and was found to be effective in wound healing and maturation of the scar. Both preparations resulted in better wound healing when compared to the untreated control group and vaseline-treated group. This effect was comparable to that induced by MEBO, the positive control. CONCLUSION The results indicate that A. fragrantissima has a pro-angiogenic effect, which may act through the VEGF signaling pathway.
Background: Androgens potentially have an important role in the biology of breast cancer, particularly triple-negative breast cancer (TNBC). Androgen receptor (AR) may offer a novel therapeutic strategy, including the use of microRNA (miRNA) molecules. We have previously shown that AR agonist, dihydrotestosterone (DHT), increases the expression of miR-328-3p in the TNBC MDA-MB-231 cells. One target of the latter miRNA is ATP-binding cassette subfamily G member 2 (ABCG2), which modulates the chemo-response of cancer cells by pumping out xenobiotics. Objective: Using MDA-MB-231 cells as a model system for TNBC, we hypothesized that DHT would induce cell sensitivity towards doxorubicin via increasing levels of miR-328-3p and, consequently, reducing ABCG2 levels. Methods: Chemo-response of cells towards doxorubicin, tamoxifen, and mitoxantrone was evaluated using cell viability MTT assay. Cells were transfected with both miR-328-3p mimic or antisense molecules. Real-time PCR was utilized to assess RNA levels and immunoblotting was performed to investigate levels of ABCG2 protein. PCR arrays were used to assess changes in the expression of drug response regulatory genes. Results: Contrary to our hypothesis, treating MDA-MB-231 cells with DHT no effect towards tamoxifen or mitoxantrone, increased cell resistance towards doxorubicin was noted, concomitant with decreased expression of ABCG2. This under-expression of ABCG2 was also found in MCF-7 and MDA-MB-453 cells treated with DHT. Although miR-328-3p decreased ABCG2 mRNA and protein levels, the miRNA did not alter the chemo-response of cells towards doxorubicin and did not affect DHT-induced chemo-resistance. AR activation slightly decreased the expression of 5 genes, including insulin-like growth factor 1 receptor that may explain the mechanism of DHT-induced chemo-resistance of cells. Conclusion: DHT regulates chemo-response via a mechanism independent of ABCG2 and miR-328-3p.
Four new complexes derived from adamantly containing hydrazone (APH) ligand with Cu(II) (1), Co(II) (2), Ni(II) (3) and Zn(II) (4), have been synthesized and characterized using different physicochemical methods. The structure of the ligand APH and its copper complex 1 have been established by single-crystal X-ray diffraction direct methods, which reveal that complex 1 has distorted square-pyramidal geometry. Complexes 1–4 are screened against seven human cancer cell lines namely, breast cancer cell lines (MCF7, T47D, MDA-MB-231), prostate cancer cell lines (PC3, DU145) and the colorectal cancer cell line Coco-2, for their antiproliferative activities. Complex 1 has shown a promising anticancer activity compared to the other ones. The structural and spectroscopic analysis of APH and its complexes are confirmed by DFT calculations.
Objective: This study aims to identify the changes in the expression of hypoxia-inducible genes in seven different cancer cell lines that vary in their oxygen levels in an attempt to identify hypoxia biomarkers that can be targeted in therapy. Profiling of hypoxia inducible-gene expression of these different cancer cell lines can be used as baseline data for further studies. Methods: Human cancer cell lines obtained from the American Type Culture Collection were used; MCF7 breast cancer cells, PANC-1 pancreatic cancer cells, PC-3 prostate cancer cells, SH-SY5Y neuroblastoma brain cancer cells, A549 lung cancer cells, and HEPG2 hepatocellular carcinoma. In addition, we used the MCF10A non-tumorigenic human breast epithelial cell line as a normal cell line. The differences in gene expression were examined using real-time PCR array (PAHS-032Z, Human Hypoxia Signaling Pathway PCR Array) and analyzed using the Delta Delta Ct method. Results: Almost all hypoxia-inducible genes showed a PO2-dependent up- and down-regulated expression. Noticeable gene expression differences were identified. The most important changes occurred in the HIF1 alpha and NF-KB signaling pathways targeted genes and in central carbon metabolism pathway genes such as HKs, PFKL, and solute transporters. Conclusion: This study identified possible hypoxia biomarkers genes such as NF-KB, HIF1 alpha, HK, PFKL, and PIM1 that were expressed in all hypoxic cells. Pleiotropic pathways that play a role in inducing hypoxia directly, such as HIF1 alpha and NF-kB pathways, were upregulated. In addition, genes expressed only in the severe hypoxic liver and pancreatic cells indicate that severe and intermediate hypoxic cancer cells vary in their gene expression. Gene expression differences between cancer and normal cells showed the shift in gene expression profile to survive and proliferate under hypoxia.
Treatment of 1,4-(SeSiMe3)2-C6H4 (1) with two equiv of ClC(O)R (2) (a, R = 2-cC4H3O; b, R = 2-cC4H3S; c, R = 3-cC4H3S) produced the corresponding phenylene carboselenolates 1,4-(SeC(O)R)2-C6H4 (3a–c), while the reaction of 1,4-(SLi)2-C6H4 (4) with ClC(O)R (2) in a 1:2 molar ratio gave phenylene carbothiolates 1,4-(SC(O)R)2-C6H4 (5a–c). Compounds 3a–c and 5a–c were characterized by elemental analysis, NMR (1H, 13C{1H}, 77Se{1H}) and IR spectroscopy. The molecular structures of 3a–c and 5a–c in the solid state were determined by single-crystal X-ray structure analysis. The carbochalcogenato groups and the heteroatoms of the 5-membered rings are in an anti-arrangement with respect to each other. Cyclic voltammetry measurements show irreversible reduction processes for the 5-membered heterocyclic redox moiety in which reduction of these compounds lead to decomposition of the original compounds to unidentified species and show redox potentials between 1480 and 1580 mV for 3a-c and 1470−1490 mV for 5a-c, relative to the FcH/FcH+ redox couple. Also, thioester-functionalized systems 5a-c show significantly higher reduction potentials as compared to selenoesters 3a-c, reflecting the minor electron-donating effect of the sulfur atoms. The molecular electronic structures of the title compounds were additionally investigated by DFT calculations, revealing different degrees of HOMO-LUMO energy gaps within the series of 3a–c and 5a–c, due to a lowering in LUMO energy, depending on the nature of the heterocyclic ring. The calculations showed that the HOMO and LUMO are mainly located on the selenoester/thioester functionalized heterocyclic. The phase transition temperatures and enthalpies of the title compounds were detected by differential scanning calorimetry (DSC) analysis and the phases are confirmed by polarizing optical microscopy (POM). The mesomorphic investigation shows that compound 5a only exhibits enantiotropic smectic B (SmB) mesophase. In contrast, the other compounds do not show mesomorphic behavior, but simply changes from the solid crystalline state to the isotropic liquid. Biological activity of the compounds was evaluated using cytotoxicity assay on different cancer cell lines. Only compound 3c showed selective cytotoxic effect against MDA-231 and PC-3 cancer cell lines. The synthesis and characterization of phenylene carboselenolates 1,4-(SeC(O)R)2-C6H4 (3a–c) and phenylene carbothiolates 1,4-(SC(O)R)2-C6H4 (5a–c) were discussed. The solid state structures of the six compounds are reported. Electrochemical investigations show irreversible redox events. DFT calculations reveal different HOMO-LUMO gaps depending on the aryl substituent pattern. In addition, the liquid crystalline properties and the bioactivity test were carried out too.
Cisplatin and carboplatin are integral parts of many antineoplastic management regimens. Both platinum analogues are potent DNA alkylating agents that robustly induce genomic instability and promote apoptosis in tumor cells. Although the mechanism of action of both drugs is similar, cisplatin appears to be more cytotoxic. In this study, the genotoxic potential of cisplatin and carboplatin was compared using chromosomal aberrations (CAs) and sister-chromatid exchange (SCE) assays in cultured human lymphocytes. Results showed that cisplatin and carboplatin induced a significant increase in CAs and SCEs compared to the control group (p<0.01). Levels of induced CAs were similar in both drugs; however, the magnitude of SCEs induced by cisplatin was significantly higher than that induced by carboplatin (p<0.01). With respect to the mitotic and proliferative indices, both cisplatin and carboplatin significantly decreased mitotic index (p<0.01) without affecting the proliferative index (p>0.05). In conclusion, cisplatin was found to be more genotoxic than carboplatin in the SCE assay in cultured human lymphocytes, and that might explain the higher cytotoxicity of cisplatin.
Background Breast cancer is the most common type of cancer among females. Hypoxia mediates cancer hallmarks and results from reduced oxygen level due to irregularities in tumor vascularization or when the tumor size prevents oxygen diffusion and triggers angiogenesis to compensate for low oxygen. Cancer stem cells (CSCs) are a rare subpopulation, able to self-renew and to give rise to tumor-initiating cells. It is proposed that CSCs’ secretions help to recruit endothelial cells via angiogenic factors to establish tumor vascularization. In the tumor microenvironment, the effect of hypoxia on CSCs and the impact of their secretions on triggering angiogenesis and tumor vascularization remain questionable. In this study, three-dimensional (3D) CSCs derived from MCF-7 were directly exposed to repetitive long-term cycles of hypoxia to assess its effect on CSCs and then to evaluate the role of the hypoxic CSCs’ (CSCsHYP) secretions in angiogenesis using (HUVECs) as a model for tumor neovascularization response. Methods CSCs derived from MCF-7 cell-line were expanded under repetitive, strictly optimized, long-term/continuous and intermittent hypoxic shots for almost four months to assess hypoxic effect on CSCs, sorted based on CD44+/CD24− biomarkers. Hypoxic phenotype of CSCsHYP was evaluated by assessing the acquired chemoresistance using MTT assay and elevated stemness properties were assessed by flow cytometry. To evaluate the effect of the secretions from CSCsHYP on angiogenesis, HUVECs were exposed to CSCsHYP conditioned-medium (CdM)—in which CSCs had been previously grown—to mimic the tumor microenvironment and to assess the effect of the secretions from CSCsHYP on the HUVECs’ capability of tube formation, migration and wound healing. Additionally, co-culture of CSCsHYP with HUVECs was performed. Results CSCsHYP acquired higher chemoresistance, increased stemness properties and obtained greater propagation, migration, and wound healing capacities, when compared to CSCs in normoxic condition (CSCsNOR). HUVECs’ tube formation and migration abilities were mediated by hypoxic (CSCs) conditioned media (CdM). Discussion This study demonstrates that chemoresistant and migrational properties of CSCs are enhanced under hypoxia to a certain extent. The microenvironment of CSCsHYP contributes to tumor angiogenesis and migration. Hypoxia is a key player in tumor angiogenesis mediated by CSCs.
A number of novel bicinnolines containing piperazine moieties, 4a–o, were synthesized via polyphosphoric acid‐catalyzed intramolecular cyclization of the respective acyl amidrazone derivatives (3a–o). On the other hand, the amidrazones (3a–o) were prepared by reaction of N′,N″‐(biphenyl‐4,4′‐diyl)bis(2‐oxopropane hydrazonoyl chloride) (2) with the appropriate cyclic sec‐amines in the presence of trimethylamine in absolute ethanol. Structures of the newly synthesized compounds were confirmed by NMR and mass spectral data. The antitumor activity of compounds 4a–o was evaluated in vitro on human breast cancer MDA‐231 by a cell viability assay. Results revealed that compounds 4k, 4n, and 4o exhibit potential cytotoxic effects (>70%) on the cancer cells. Additionally, the antimicrobial activity of compounds 4a–o was evaluated against three clinical microbial strains: Escherichia coli (Gram‐negative bacteria), Staphylococcus aureus (Gram‐positive bacteria), and Candida albicans (fungi/yeast). Results revealed that compounds 4e and 4k exhibit good activity against all three strains included in the study and that compound 4d displays excellent activity against S. aureus strain with a minimum inhibitory concentration value of 0.187 mg/mL.
Post-traumatic stress disorder (PTSD) is a psychiatric disorder that can happen after exposure to a traumatic event. Post-traumatic stress disorder is common among mental health disorders that include mood and anxiety disorders. Omega-3 fatty acids (OMGs) are essential for the maintenance of brain function and prevention of cognition dysfunctions. However, the possible effect of OMG on memory impairment induced by PTSD has not been studied. In here, such an effect was explored using a rat model of PTSD. The PTSD-like behavior was induced in animals using a single-prolonged stress (SPS) rat model of PTSD (2 h restraint, 20 min forced swimming, 15 min rest, 1–2 min diethyl ether exposure). The OMG was administered orally at a dose of 100 mg omega-3 polyunsaturated fatty acid (PUFA)/100 g body weight/day. Spatial learning and memory were assessed using the radial arm water maze (RAWM) method. Changes in oxidative stress biomarkers, thiobarbituric acid reactive substances (TBARS), and brain derived neuroptrophic factor (BDNF) in the hippocampus following treatments were measured. The results revealed that SPS impaired both short- and long-term memory (p < 0.05). Use of OMG prevented memory impairment induced by SPS. Furthermore, OMG normalized SPS induced changes in the hippocampus that reduced glutathione (GSH), oxidized glutathione (GSSG), GSH/GSSG ratios, the activity of catalase, glutathione peroxidase (GPx), and TBARSs levels. In conclusion, the SPS model of PTSD-like behavior generated memory impairment, whereas OMG prevented this impairment, possibly through normalizing antioxidant mechanisms in the hippocampus.
Purpose: To investigate hypoxia-induced gene expression pattern in doxorubicin-resistant human breast cancer cells (MCF7). Methods: Human breast cancer cells (MCF7) were exposed to 60 episodes of 8 h hypoxia thrice a week for three months. Chemo-resistance to doxorubicin was assessed using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) cell proliferation assay. Real-time quantitative polymerase chain reaction (qRT-PCR) assay was performed to assess gene expression pattern in doxorubicin-resistant cells on exposure to hypoxia. Results: Hypoxia significantly increased the resistance of MCF7 cells to doxorubicin, with a maximum of 16.42-fold enhancement after 25 episodes of 8-h hypoxia, while the resistance thereafter significantly decreased with prolonged episodes of hypoxia (p < 0.05). Gene expression analysis revealed significant changes in 42 genes. The expressions of 10 of these genes were significantly upregulated, while those of 32 genes were significantly down-regulated (p < 0.05). Cytochrome P450 family 1, subfamily A, member1 (CYP1A1) was the most conspicuous upregulated gene (13.32-fold), while breast cancer gene 1 (BRCA1) was the most down-regulated (8.23-fold). Gene expression analysis after 60 episodes of 8-h hypoxia revealed the upregulation of CYP1A1 (5.77-fold). Similarly, 27 genes were significantly down-regulated, with BRCA2 as the most down-regulated gene (8.11-fold). Topoisomerase (DNA) II alpha (TOP2A) was the most down-regulated among genes involved in drug metabolism and resistance (6.37-fold), while cyclin-dependent kinase 2 (CDK2) was the most profoundly downregulated among genes involved in cell cycle regulation (3.56-fold). Conclusion: These results indicate that development of resistance to doxorubicin by MCF7 cells after short-term hypoxia results from the upregulation of genes responsible for the metabolism of doxorubicin and for shifting the cells to alternative pathway driven principally by EGF and ESR2. The observed down-regulation is an adaptation of the MCF7 cells to survive under long-term hypoxia.
Introduction: Psychosocial stress (STS) negatively influences memory. This might be associated to oxidative stress-induced progressive destruction of numerous brain structures and functions. L-carnitine (L-CAR) is a widely used antioxidant compound that is endogenously made in mammalian species. The current study investigated the effect of L-CAR on STS-induced memory impairment in the rat hippocampus. Methods: The STS was induced using intruder model, where two rats were randomly switched from each one cage to another, once/day for 6 weeks. Concurrently, L-CAR (300mg/kg/day) was intraperitoneally administered for 6 weeks. After that, radial arm water maze (RAWM) was used to assess spatial learning memory in rats. Hippocampal biomarkers of oxidative stress, including thiobarbituric acid reactive substance (TBARs), oxidized glutathione (GSSG), reduced glutathione (GSH), glutathione peroxidase (GPx), catalase, and superoxide dismutase (SOD), and Brain-derived neurotrophic factor (BDNF) were examined. Results: The results showed impairment of short-term memory (P < 0.05) during STS, whereas L-CAR treatment protected against this effect. Furthermore, while no change was observed in GSH, GSSG, GPx, catalase, and SOD, L-carnitine normalized STS-induced reduction in the hippocampal BDNF levels and increase in TBARS levels. Discussion: Chronic psychosocial stress-induced memory impairment was prevented via L-CAR administration, which could have been achieved via normalizing changes in lipid peroxidation (TBARs) and BDNF levels in the hippocampus.