N-methyl-D-aspartate receptors and thymoquinone induce apoptosis and alteration in mitochondria in colorectal cancer cells.

Colon cancer is on the rise in both men and women. In addition to traditional treatment methods, herbal treatments from complementary and alternative medicine are actively followed. Naturally derived from plants, thymoquinone (TQ) has drawn a lot of attention in the field of cancer treatment. MK-801, an N-methyl-D-aspartate agonist, is used to improve memory and plasticity, but it has also lately been explored as a potential cancer treatment. This study aimed to determine the roles of N-Methyl-D-Aspartate agonists and Thymoquinone on mitochondria and apoptosis. HT-29 cells were treated with different TQ and MK-801 concentrations. We analyzed cell viability, apoptosis, and alteration of mitochondria. Cell viability significantly decreased depending on doses of TQ and MK-801. Apoptosis and mitochondrial dysfunctions induced by low and high doses of TQ and MK-801. Our study emphasizes the need for further safety evaluation of MK-801 due to the potential toxicity risk of TQ and MK-801. Optimal and toxic doses of TQ and MK-801 were determined for the treatment of colon cancer. It should be considered as a possibility that colon cancer can be treated with TQ and MK-801.

Investigating anti-cancer activity of dual-loaded liposomes with thymoquinone and vitamin C.

Background: Thymoquinone (TQ) and vitamin C (Vit C) have demonstrated individual anticancer effects in various studies. TQ exhibits inhibitory properties against tumor growth, induces apoptosis, while Vit C protects against DNA damage and oxidative stress. Aim: Formulation of TQ and Vit C combination into liposomes using two methods and investigate the synergistic anticancer. Method: Liposomal preparations were characterized, and the purity of drug components was confirmed using encapsulation efficiency (EE %). Results: In vitro cell viability studies demonstrated the inhibitory effect of TQ and Vit C against colorectal (HT29, 5.5 ± 0.9 µM) and lung cancer (A549, 6.25 ± 0.9 µM) cell lines with combination index <1. Conclusion: The formulation of TQ and Vit C displayed synergistic anticancer activity.

Exploring MTH1 inhibitory potential of Thymoquinone and Baicalin for therapeutic targeting of breast cancer.

Cancers frequently have increased ROS levels due to disrupted redox balance, leading to oxidative DNA and protein damage, mutations, and apoptosis. The MTH1 protein plays a crucial role by sanitizing the oxidized dNTP pools. Hence, cancer cells rely on MTH1 to prevent the integration of oxidized dNTPs into DNA, preventing DNA damage and allowing cancer cell proliferation. We have discovered Thymoquinone (TQ) and Baicalin (BC) as inhibitors of MTH1 using combined docking and MD simulation approaches complemented by experimental validations via assessing binding affinity and enzyme inhibition. Docking and MD simulations studies revealed an efficient binding of TQ and BC to the active site pocket of the MTH1, and the resultant complexes are appreciably stable. Fluorescence measurements estimated a strong binding affinity of TQ and BC with Ka 3.4 ×106 and 1.0 ×105, respectively. Treating breast cancer cells with TQ and BC significantly inhibited the growth and proliferation (IC50 values 28.3 µM and 34.8 µM) and induced apoptosis. TQ and BC increased the ROS production in MCF7 cells, imposing substantial oxidative stress on cancer cells and leading to cell death. Finally, TQ and BC are proven strong MTH1 inhibitors, offering promising prospects for anti-cancer therapy.

Computational and in vitro analyses on synergistic effects of paclitaxel and thymoquinone in suppressing invasive breast cancer cells.

BACKGROUND: In the present experiment, we evaluated the impact of thymoquinone (TQ) and paclitaxel (PTX) treatment on MDA-MB-231 cell line growth inhibition via controlling apoptosis/autophagy. MATERIALS AND RESULTS: MDA-MB-231cells were exposed to PTX (0, 25, 50, 75, and 100 nM), TQ (0, 25, 50, 75, and 100 µM), and combinations for 48 h. After the MTT assessment, dose-response curves and IC50 values were calculated, and the combination synergism was evaluated using the Compusyn software. Following the treatment with PTX, TQ, and combinations at IC50 doses, the expression of apoptosis and autophagy genes was assessed in cells. The GraphPad Prism program was used to analyze the data, and Tukey's test at p < 0.05 was then run. PTX, TQ, and their combinations inhibited MDA-MB-231cell proliferation and viability dose-dependently. TQ reduced the effective concentration (IC50) of PTX in co-treatment groups. PTX and TQ showed antagonistic effects when cell proliferation declined above 70%. Antagonistic effects shifted into additive and synergistic effects upon increasing PTX concentration, indicated by diminished cell proliferation below 70%. PTX-TQ co-treatment significantly enhanced P53 and BAX expression while reducing Bcl-2 expression. Also, their combination increased Beclin-1, ATG-5, and ATG-7 expression in treated cells. CONCLUSION: Effective concentrations of TQ and PTX had synergic effects and inhibited breast cancer cells via prompting apoptosis and autophagy in vitro.

Influences of compound age and identity in the effectiveness of insect quinone secretions against the fungus Beauveria bassiana.

Chemical defences against parasites and pathogens can be seen in a wide range of animal taxa, including insect pests such as the red flour beetle Tribolium castaneum. Antimicrobial quinone-based secretions can be used by these beetles to defend against various parasites, particularly the fungal entomopathogen Beauveria bassiana. While quinone secretions can inhibit B. bassiana growth, it is unknown how long they remain effective or how individual secretion compounds contribute to growth inhibition. Here, we tested each individual component of the quinone secretions (methyl-1,4-benzoquinone, ethyl-1,4-benzoquinone, and 1-pentadecene), as well as two mixed solutions that represent the composition range found in natural T. castaneum secretions, after aging for 0, 24, or 72 h. The two quinone compounds equally contributed to B. bassiana inhibition, but their efficacy was significantly reduced after 24 h, with no growth inhibition after 72 h. This indicates that quinones protect insects against B. bassiana for only a limited time, perhaps requiring constant secretion into the environment to effectively defend against this fungal threat. Future investigations may consider the extent to which quinone secretions are effective against other parasites, as well as how their ability to cause parasite damage changes with compound age.

Ameliorative effects of thymoquinone on the caspase 3, kidney function and oxidative stress tartrazine-induced nephrotoxicity.

First in the literature this study aimed to investigate the effects of Tartrazine, a common industrial food dye, on kidney and whether Thymoquinone has a protective effect in tartrazine-induced nephrotoxicity. The study conducted on the rats bred at Inönü University Experimental Animals Production and Research Center. Wistar albino rats were randomly divided into 4 groups, where each group included 8 rats: control, Tartrazine, Thymoquinone, and Tartrazine + Thymoquinone groups. The experiments continued for 3 weeks and then, kidney tissues and blood samples were collected from the rats under anesthesia. Malondialdehyde (MDA), super oxidized dismutase (SOD), total oxidant status (TOS), increase in Oxidative stress index (OSI), glutathione (GSH), Glutathione peroxidase (GSH-Px), catalase (CAT), Total antioxidant status (TAS) levels decreased in the kidney tissues collected from the tartrazine group. Serum Bun and Creatinine levels increased in the tartrazine group. Tartrazine administration damaged and degenerated the glomeruli and cortical distal tubes in the histopathology of kidney tissues, also different degrees of inflammatory cell infiltration were observed in the renal cortex and medulla. Thymoquinone and tartrazine administration improved both biochemical and histopathological parameters. Tartrazine administration induced nephrotoxicity. This could be observed with the increase in oxidant capacity and the deterioration of kidney functions. Thymoquinone was observed to demonstrate strong antioxidant properties. Thymoquinone could be used primarily as a protective agent against Tartrazine-induced toxicity.

Effects of thymoquinone in the lungs of rats against radiation-induced oxidative stress.

OBJECTIVE: Radiotherapy is an important treatment for a wide variety of malignancies, although many cancer patients who receive radiotherapy suffer from serious side effects during and after their treatment. Thymoquinone (TQ), the main active ingredient of Nigella sativa, has been reported to have various pharmacological properties, such as antioxidant, hepatoprotective, neuroprotective, antidiabetic, anti-inflammatory, nephroprotective, anticarcinogenic in many pharmacological and toxicological studies. In this study, we aimed to investigate whether there is a radioprotective effect of TQ on the lung tissue of rats exposed to ionizing radiation. MATERIALS AND METHODS: This study was designed as a prospective, placebo-controlled study. A total of 40 Sprague-Dawley rats were divided into four groups to test the radiation-protective effectiveness of TQ administered by intraperitoneal injection. Biochemical parameters were studied to assess the radiation-protective effects of TQ. RESULTS: Oxidative stress parameters, such as oxidative stress index (OSI), lipid hydroperoxide (LOOH) and total oxidant status (TOS), in lung tissue of the rats treated with TQ, were found to be lower than in received irradiation alone. Anti-oxidative parameters, such as total antioxidant status (TAS) level and paraoxonase (PON) activity, were statistically higher in the TR (IR plus TQ group) group compared with other groups. CONCLUSIONS: Findings show that TQ clearly protects lung tissue from radiation-induced oxidative stress and can be used as a radioprotective agent.

In Vitro and In Vivo Preventive Effects of Thymoquinone against Breast Cancer: Role of DNMT1.

Breast cancer (BC) is one of the most common cancers in women and is a major cause of female cancer-related deaths. BC is a multifactorial disease caused by the dysregulation of many genes, raising the need to find novel drugs that function by targeting several signaling pathways. The antitumoral drug thymoquinone (TQ), found in black seed oil, has multitargeting properties against several signaling pathways. This study evaluated the inhibitory effects of TQ on the MCF7 and T47D human breast cancer cell lines and its antitumor activity against BC induced by a single oral dose (65 mg/kg) of 7,12-dimethylbenzanthracene (DMBA) in female rats. The therapeutic activity was evaluated in DMBA-treated rats who received oral TQ (50 mg/kg) three times weekly. TQ-treated MCF7 and T47D cells showed concentration-dependent inhibition of cell proliferation and induction of apoptosis. TQ also decreased the expression of DNA methyltransferase 1 (DNMT1) in both cancer cell types. In DMBA-treated animals, TQ inhibited the number of liver and kidney metastases. These effects were associated with a reduction in DNMT1 mRNA expression. These results indicate that TQ has protective effects against breast carcinogens through epigenetic mechanisms involving DNMT1 inhibition.

Thymoquinone-protoflavone hybrid molecules as potential antitumor agents.

We describe herein the synthesis of eight new ester-coupled hybrid compounds from thymoquinone and protoflavone building blocks, and their bioactivity testing against multiple cancer cell lines. Among the hybrids, compound 14 showed promising activities in all cell lines studied. The highest activities were recorded against breast cancer cell lines with higher selectivity to MDA-MB-231 as compared to MCF-7. Even though the hybrids were found to be completely hydrolysed in 24 h under cell culture conditions, compound 14 demonstrated a ca. three times stronger activity against U-87 glioblastoma cells than a 1:1 mixture of its fragments. Further, compound 14 showed good tumour selectivity: it acted 4.4-times stronger on U-87 cells than on MRC-5 fibroblasts. This selectivity was much lower, only ca. 1.3-times, when the cells were co-treated with a 1:1 mixture of its non-coupled fragments. Protoflavone-thymoquinone hybrids may therefore serve as potential new antitumor leads particularly against glioblastoma.

Nicotine promotes epithelial to mesenchymal transition and gemcitabine resistance via hENT1/RRM1 signalling in pancreatic cancer and chemosensitizing effects of Embelin-a naturally occurring benzoquinone.

Pancreatic cancer is lethal due to poor prognosis with 5-year survival rate lesser than 5 %. Gemcitabine is currently used to treat pancreatic cancer and development of chemoresistance is a major obstacle to overcome pancreatic cancer. Nicotine is a known inducer of drug resistance in pancreatic tumor micro-environment. Present study evaluates chemoresistance triggered by nicotine while treating with gemcitabine and chemosensitization using Embelin. Embelin is a naturally occurring benzoquinone from Embelia ribes possessing therapeutic potency. To develop nicotine-induced chemo-resistance, pancreatic cancer cells PANC-1 and MIA PaCa-2 were continuously treated with nicotine followed by exposure to gemcitabine. Gemcitabine sensitivity assay and immunoblotting was performed to assess the chemo-resistance. Antiproliferative assays such as migration assay, clonogenic assay, Mitochondrial Membrane Potential (MMP) assay, dual staining assay, comet assay, Reactive Oxygen Species (ROS) assay, cell cycle analysis and immunoblotting assays were performed to witness the protein expression involved in chemoresistance and chemosensitization. Epithelial to mesenchymal transition was observed in nicotine induced chemoresistant cells. Gemcitabine sensitivity assay revealed that relative resistance was increased to 6.26 (p < 0.0001) and 6.45 (p < 0.0001) folds in resistant PANC-1 and MIA PaCa-2 compared to parental cells. Protein expression studies confirmed resistance markers like hENT1 and dCK were downregulated with subsequent increase in RRM1 expression in resistant cells. Embelin considerably decreased the cell viability with an IC50 value of 4.03 ± 0.08 µM in resistant PANC-1 and 2.11 ± 0.04 µM in resistant MIA PaCa-2. Cell cycle analysis showed Embelin treatment caused cell cycle arrest at S phase in resistant PANC-1 cells; in resistant MIA PaCa-2 cells there was an escalation in the Sub G1. Embelin upregulated Bax, γH2AX, p53, ERK1/2 and hENT1 expression with concomitant down regulation of Bcl-2 and RRM1. Bioactive molecule embelin, its combination with gemcitabine could provide new vistas to overcome chemo resistance in pancreatic cancer.

HSP90 Inhibition Attenuated Isoflurane-Induced Neurotoxicity in Mice and Human Neuroglioma Cells.

Isoflurane, a widely used inhalation anesthetic in clinical practice, is associated with an increased risk of neuronal injury. Heat shock protein 90 (HSP90) plays a crucial role in maintaining neuronal homeostasis under stress conditions; however, its role during isoflurane exposure remains poorly understood. In this study, we aimed to investigate the protective effects of HSP90 inhibition and explore the regulatory mechanisms underlying these effects during isoflurane exposure. We found that the HSP90 inhibitor 17-N-allylamino-17-demethoxygeldanamycin (17 AAG) has great protective effects in mitigating isoflurane-induced ferroptosis of mouse hippocampus and cultured neuronal cells. We focused on the activity of the crucial protein GPX4 in ferroptosis and found that 17 AAG exerted protective effects, preserving the physiological GPX4 activity under isoflurane exposure; further, 17 AAG restored the protein level of GPX4. Further, we observed that the chaperone-mediated autophagy (CMA) pathway was activated; 17 AAG also mediated GPX4 degradation under isoflurane exposure. Additionally, it interfered with the formation of complexes between HSP90 and Lamp-2a, inhibiting CMA activity, followed by the blockade of GPX4 degradation, further affecting the isoflurane-induced ferroptosis. Based on these findings, we proposed HSP90 inhibition as a protective mechanism against isoflurane-induced ferroptosis in neurons.

Blocking exosomal secretion aggravated 1,4-benzoquinone-induced cytotoxicity.

Benzene exposure inhibits the hematopoietic system and leads to the occurrence of various types of leukemia. However, the mechanism underlying the hematotoxicity of benzene is still largely unclear. Emerging evidence has shown that exosomes are involved in toxic mechanisms of benzene. To understand the effect of 1,4-benzoquinone (PBQ; an active metabolite of benzene in bone marrow) on the exosomal release characteristics and role of exosomal secretion in PBQ-induced cytotoxicity. Exosomes were isolated from PBQ-treated HL-60 cells, purified by ultracentrifugation, and verified by transmission electron microscopy, nanoparticle tracking analysis and the presence of specific biomarkers. Our results showed that PBQ increased exosomal secretion in a dose-dependent manner, reaching a peak in 3 h at 10 µM PBQ treatment and then slowly decreasing in HL-60 cells. The exosomes contained miRNAs, which have been reported to be associated with benzene exposure or benzene poisoning. In particular, mir-34a-3p and mir-34A-5p were enriched in exosomes derived from PBQ-treated cells. In addition, the inhibition of exosomal release by GW4869 (an inhibitor of exosomal release) exacerbated PBQ-induced cytotoxicity, including increased intracellular reactive oxygen species levels, decreased mitochondrial membrane potential, and increased the apoptosis rate. Our findings illustrated that exosomes secretion plays an important role in antagonizing PBQ-induced cytotoxicity and maintaining cell homeostasis.

ent-Clavilactone J and Its Quinone Derivative, Meroterpenoids from the Fungus Resupinatus sp.

Metabolites 1 and 2, isolated from cultures of the basidiomycete Resupinatus sp. BCC84615, collected in a tropical forest in northeastern Thailand, showed weak antibiotic activity against Bacillus subtilis and Staphylococcus aureus and cytotoxicity against cancer cell lines. Their planar structures were elucidated by high-resolution electrospray ionization mass spectrometry and NMR spectroscopy as clavilactone J, known from the basidiomycete Ampulloclitocybe clavipes, and its new 1,4-benzoquinone derivative. A detailed analysis of the ROESY correlations in 1 confirmed the recent revision of the relative configuration of clavilactone J. However, specific rotation and Cotton effects observed by electronic circular dichroism were contrary to those of the clavilactones; thus, we assigned a rare antipodal absolute configuration.

Antibacterial activity of thymoquinone derivative.

Natural products such as terpenoidal compounds have been extremely tested against pathogenic bacteria. Researches are frequently carried out to find out new natural, semisynthetic and synthetic antibacterial agents due to problems of resistance. Thymoquinone derivative was obtained in our previous study and the current research is a continuation. The antibacterial activity of a monoterpenoid; thymoquinone derivative, 5-isopropyl-2-methyloxepine-1-one (1) has been evaluated for the first time by following the Agar cup bioassay method employed. The bacterial strains used in this study were Escherichia coli and Bacillus subtilis. Compound 1 showed moderate activity against Gram-positive organism; B. subtilis and good activity against Gram-negative species; E. coli with zones of inhibition (ZOI) 10.0 ± 0.2 mm and 11.0 ± 0.2 mm against E. coli and B. subtilis, respectively, and in comparison with antibiotic, imipenem. The zones of inhibition were calculated as the mean of the triplicate. The antibacterial activity of thymoquinone derivative 1 could be explained by the presence of unsaturated lactone.

Thymoquinone attenuates olanzapine-induced metabolic disorders in rats.

BACKGROUND: Olanzapine (OLZ) is an atypical antipsychotic agent for psychotic disorders. Evidence has shown that OLZ is related to metabolic side effects, including obesity, hypertension, and insulin resistance. Thymoquinone (TQ) is the principal bioactive component of Nigella sativa. Several studies have been conducted to investigate the effectiveness of TQ in alleviating metabolic abnormalities. In the current research work, the protective effects of TQ on metabolic disorders induced by OLZ and possible underlying mechanisms were investigated. METHODS AND RESULTS: Wistar rats were exposed to TQ alone (10 mg/kg), OLZ (5 mg/kg), or OLZ plus TQ (2.5, 5, or 10 mg/kg) given daily by intraperitoneal injection. After the treatment, variations in body weight, food intake, systolic blood pressure, serum leptin, biochemical factors, liver malondialdehyde (MDA), and glutathione (GSH) content were evaluated. Protein expression of AMPK in the liver was also measured by a western blotting test. OLZ increased body weight, food intake, MDA levels, and blood pressure. OLZ also elevated glucose, triglyceride, low-density lipoprotein cholesterol, and leptin serum levels. It decreased GSH. In the western blot, decreased AMPK protein level was obtained. These changes were attenuated by TQ co-administration. CONCLUSIONS: The present study demonstrates the effectiveness of TQ on OLZ-induced metabolic abnormalities related to its antioxidant activity and regulation of glucose homeostasis and lipid metabolism.

Embelin inhibits viability of cutaneous T cell lymphoma cell lines HuT78 and H9 by targeting inhibitors of apoptosis.

Cutaneous T cell lymphoma (CTCL) is a varied group of neoplasms that affects the skin. Acquired resistance against chemotherapeutic drugs and associated toxic side effects are limitations that warrant search for novel drugs against CTCL. Embelin (EMB) is a naturally occurring benzoquinone derivative that has gained attention owing to its anticancer pharmacological actions and nontoxic nature. We assessed the anticancer activity of EMB against CTCL cell lines, HuT78, and H9. EMB inhibited viability of CTCL cells in a dose-dependent manner. EMB activated extrinsic and intrinsic pathways of apoptosis as shown by the activation of initiator and executioner caspases. EMB-induced apoptosis also involved suppression of inhibitors of apoptosis, XIAP, cIAP1, and cIAP2. PARP cleavage and upregulation of pH2AX indicated DNA damage induced by EMB. In conclusion, we characterized a novel apoptosis-inducing activity of EMB against CTCL cells, implicating EMB as a potential therapeutic agent against CTCL.

Effect of thymoquinone on endoplasmic reticulum (ER) stress in NRK-52e cells.

Thymoquinone (TQ), the active component of Nigella sativa, has many beneficial effects. The endoplasmic reticulum involved in the quality control of protein translocation and folding can vary under different conditions, the phenomenon of causing the accumulation of unfolded or misfolded proteins within the ER lumen is termed ER stress. This in vitro study was planned to investigate the effect of TQ on ER stress at proliferative (Tp) and toxic (TQIC50) concentrations on NRK-52E cells at 24th, 48th hours. The expression of important genes in the ER stress pathway (ATF4, ATF6, BIP, CHOP, IRE1, XBP1, PERK) was analyzed. Expression of all genes except CHOP and XBPI increased at 24 hours and BIP at 48 hours for Tp. In the IC50, the CHOP and XBPI gene expressions increased at the 24th hour, and the CHOP and ATF4 genes increased at the 48th hour. As a result, it was determined that the expression of ER stress genes had significant changes with the TQ induction, depending on time and concentration, especially in the proliferative concentration. It is thought that TQ may have varying effects on healthy kidney cells, and it is important to investigate the mechanism of this effect in further studies.

Molecular determinants of the response of cancer cells towards geldanamycin and its derivatives.

Geldanamycin is an ansamycin-derivative of a benzoquinone isolated from Streptomyces hygroscopicus. It inhibits tyrosine kinases and heat shock protein 90 (HSP90). Geldanamycin and 11 derivatives were subjected to molecular docking to HSP90, and 17-desmethoxy-17-N,N-dimethylamino-geldanamycin (17-DMAG) was the compound with the highest binding affinity (-7.73 ± 0.12 kcal/mol) and the lowest inhibition constant (2.16 ± 0.49 µM). Therefore, 17-DMAG was selected for further experiments in comparison to geldanamycin. Multidrug resistance (MDR) represents a major problem for successful cancer therapy. We tested geldanamycin and 17-DMAG against various drug-resistant cancer cell lines. Although geldanamycin and 17-DMAG inhibited the proliferation in all cell lines tested, multidrug-resistant P-glycoprotein-overexpressing CEM/ADR5000 cells were cross-resistant, ΔEGFR-overexpressing tumor cells and p53 knockout cells were sensitive to these two compounds. COMPARE and hierarchical cluster analyses were performed, and 60 genes were identified to predict the sensitivity or resistance of 59 NCI tumor cell lines towards geldanamycin and 17-DMAG. The distribution of cell lines according to their mRNA expression profiles indicated sensitivity or resistance to both compounds with statistical significance. Moreover, bioinformatic tools were used to study possible mechanisms of action of geldanamycin and 17-DMAG. Galaxy Cistrome analyses were carried out to predict transcription factor binding motifs in the promoter regions of the candidate genes. Interestingly, the NF-ĸB DNA binding motif (Rel) was identified as the top transcription factor. Furthermore, these 60 genes were subjected to Ingenuity Pathway Analysis (IPA) to study the signaling pathway interactions of these genes. Interestingly, IPA also revealed the NF-ĸB pathway as the top network among these genes. Finally, NF-ĸB reporter assays confirmed the bioinformatic prediction, and both geldanamycin and 17-DMAG significantly inhibited NF-κB activity after exposure for 24 h. In conclusion, geldanamycin and 17-DMAG exhibited cytotoxic activity against different tumor cell lines. Their activity was not restricted to HSP90 but indicated an involvement of the NF-KB pathway.

Thymoquinone Effect on Leishmania tropica/infantum and Leishmania-Infected Macrophages.

INTRODUCTION: Leishmania is a parasitic protozoan that tries to enter and amplify within macrophages. Macrophage cells are also immune defense cells that phagocyte many microbes like bacteria, fungi, as well as parasites like Leishmania spp. However, they are unable to kill this parasite that resides in the phagosomes of contaminated macrophages and multiplies in these macrophages, leading to the destruction of contaminated macrophages and the emerging of Leishmania wounds. A large number of current therapies for Leishmania cure have adverse effects, or parasites have developed resistance to some of these therapies, so a better therapy for the cure of Leishmania is required. Thymoquinone is one of the Nigella Sativa ingredients with numerous biological effects, such as antioxidant as well as antimicrobial effects on a variety of microbes, namely fungi, bacteria, as well as parasites like Leishmania spp. The impacts of Thymoquinone on Leishmania tropica and Leishmania infantum, as well as Leishmania-infected macrophages, were examined in this study. METHODS: The impact of various Thymoquinone dosages on L. tropica and L. infantum promastigotes and amastigotes was examined in vitro. Flow cytometry, as well as MTT, was also applied to examine the cytotoxic activity of Thymoquinone on promastigotes of L. tropica and L. infantum, as well as the incidence of apoptosis. The amastigote assay is also utilized to calculate the % of contaminated macrophages as well as the number of the present parasites in each macrophage. RESULTS: The percentage of macrophages contaminated with L. tropica and L. infantum amastigotes after medicating with 20 µM of Thymoquinone was 23% and 19%, respectively. Also, after medicating with 10 µM of Thymoquinone, these percentages were 32% and 31%, respectively. Flow cytometry indicated that Thymoquinone caused 33.9% and 31.4% apoptosis in L. tropica and L. infantum, respectively. As determined by the promastigote assay, the inhibitory concentration (IC50) of Thymoquinone for L. tropica and L. infantum was 9.49 µM and 12.66 µM, respectively. The results of the promastigote and amastigote assay show that with an increase in Thymoquinone doses, its ability to kill Leishmania parasites increases, too. CONCLUSION: According to the results of the study, Thymoquinone has a potentially lethal impact on L. tropica and L. infantum promastigotes as well as amastigotes (within leishmania contaminated macrophages).

The anti-oncogenic effect of 17-DMAG via the inactivation of HSP90 and MET pathway in osteosarcoma cells.

Heat shock protein (HSP) 90 plays a crucial role in correcting the misfolded three-dimensional structure of proteins, assisting them in folding into proper conformations. HSP90 is critical in maintaining the normal functions of various proteins within cells, as essential factors for cellular homeostasis. Contrastingly, HSP90 simultaneously supports the maturation of cancer-related proteins, including mesenchymal epithelial transition factor (MET) within tumor cells. All osteosarcoma cell lines had elevated MET expression in the cDNA array in our possession. MET, a tyrosine kinase receptor, promotes proliferation and an anti-apoptotic state through the activation of the MET pathway constructed by HSP90. In this study, we treated osteosarcoma cells with an HSP90 inhibitor, 17-demethoxygeldanamycin hydrochloride (17-DMAG), and assessed the changes in the MET signaling pathway and also the antitumor effect of the drug. The cell cycle in osteosarcoma cells administered 17-DMAG was found to be halted at the G2/M phase. Additionally, treatment with 17-DMAG inhibited cell proliferation and induced apoptosis. Inhibition of tumor cell proliferation was also observed in an in vivo model system, mice that were treated with 17-DMAG. Based on the results of this study, we were able to confirm that 17-DMAG promotes inhibition of osteosarcoma cell proliferation and induction of apoptosis by inhibition of MET, a protein highly expressed in osteosarcoma cells. This approach may be useful for the establishment of a new treatment strategy for patients resistant to the standard treatment for osteosarcoma.