Cancer: Thymoquinone antioxidant/pro-oxidant effect as potential anticancer remedy

Preventive effects of thymoquinone on glyco-nitro-oxidized human fibrinogen: A comprehensive biophysical study projecting possible therapeutic role in diabetes and associated complications

Persistence of long-term hyperglycemia results in the glyco-oxidation of plasma proteins, which is considered to be a significant factor in metabolic dysfunction, linking hyperglycemia to the emergence of vascular complications. Methylglyoxal (MGO), a dicarbonyl species formed excessively under diabetes, elevates the oxidative stress, enhancing the generation of superoxide anion, which ultimately reacts with nitric oxide (NO•) to form peroxynitrite (PON). PON, being a powerful nitro-oxidizing agent distorts protein structure, hampering its function. This article describes the binding mechanism of thymoquinone (TQ) to fibrinogen (Fg) and its protective effects under simultaneous glyco-nitro-oxidation. Thermodynamic investigations revealed hydrogen bonding and Vander Waal interactions stabilise the complex, confirming its spontaneity and exothermic nature. TQ-induced micro-environmental and structural alterations in fibrinogen were observed by synchronous, 3-D fluorescence maps, and red edge excitation shift (REES). Molecular docking confirmed the wet lab experiments. Previous studies have shown that glycation, as well as nitro-oxidation, modifies the key residues of fibrinogen, leading to its aggregation. Our findings showed that TQ prevented MGO + PON-induced damage to fibrinogen. The current study analyzed the protective effects of TQ on glyco-nitro-oxidized fibrinogen using various biochemical, spectroscopic, and computational methods. NBT assay and carbonyl content revealed glyco-nitro-oxidation-mediated oxidative stress, which was effectively mitigated by TQ in a concentration-dependent manner. The secondary structural alterations in fibrinogen were prevented by TQ as observed by circular dichroism (CD) and Fourier transform infrared spectroscopy (FTIR). Moreover, multiple assays and electron microscopy confirmed structural perturbations leading to the development of fibrillar aggregates that were reduced in TQ treated samples. Our findings project TQ as a potent protective agent against hyperglycemia and related human complications.

Promotion of Autophagy and Apoptosis in Colorectal Cancer Exposed to Imatinib and Thymoquinone

Cancer cells possess high proliferative ability and usually override apoptosis and metastasize to distant lesions. Autophagy in cancer cells is a double-edged weapon where a cross-regulation postulation between apoptosis and autophagy exists. The aim of the present study was to investigate the effect of adding Thymoquinone (TQ) to Imatinib (IM) in HCT116 human colorectal cancer cell line model on various apoptotic and autophagy markers. The combination doses of IM and TQ were selected according to our previous study concerned with cytotoxicity and uptake/efflux genes modulation. In the current study, the combination induced autophagy in HCT116 cell line which in turn enhanced apoptosis. Moreover, early apoptosis was evidenced. The induction of both autophagy and apoptosis resulted in programmed cell death. The assessment of AMPK, Par-4, apoptosis markers, colony formation assays, flow cytometry and autophagy detection by acridine orange proved this rapport.

Thymoquinone Ameliorates Gut Epithelial Injury by Suppressing the JNK Signaling Pathway Based on Its Anti-Oxidant Property

Ulcerative colitis is one of the most common sorts of inflammatory bowel disease. This study investigates the protective effects of thymoquinone against sodium dodecyl sulfate (SDS)-induced intestinal damage and elucidates the underlying mechanisms using the Drosophila melanogaster model of ulcerative colitis. We found that Drosophila fed thymoquinone from larval to adult stages were resistant to SDS injury in adulthood. Thymoquinone pretreatment significantly restored the abnormal behaviors and intestinal morphological defects in Drosophila exposed to SDS. Moreover, thymoquinone protected the intestinal barrier function by inhibiting the overactivated c-Jun N-terminal kinase (JNK) pathway in the intestine induced by SDS. Further studies indicated that thymoquinone inhibits the JNK pathway by reducing intestinal reactive oxygen species (ROS) levels. This research provides novel pathological and mechanistic insights into the potential application of thymoquinone in developing functional foods or natural medicines, highlighting its significance in treating ulcerative colitis.

Biological and Molecular Efficiency of Paracentrotus lividus Shell in vitro Study: Antioxidant and Angiogenesis Effects Against T47D Breast Cancer Cell Line Via Nrf2/HMOX-1/ and HIF-1α /VEGF Signaling Pathways

The sea urchin (Paracentrotus lividus) shell investigation reveals a wealth of bioactive compounds. The bioactive ingredients were observed using UPLCMS/MS profiling. The anti-diabetic, antioxidant, antimicrobial, and anti-inflammatory qualities of P. lividus shell extract were assessed concerning NO, MDA, CAT, and SOD levels. Also, cytotoxic, and anti-angiogenic impact on colon (Caco-2) and breast (T47D) carcinoma cells and quantificated of Nrf2/HMOX-1 and HIF-1α/VEGF pathway expression were evaluated. Our findings indicate that the extract possesses remarkable antioxidant activity with IC50 equal to (0.1056 ± 0.083 and 30.42 ± 1.52 μg/mL; for DPPH and ABTS+ respectively), antidiabetic with IC50 (1.572 ± 0.13 μg/mL) and anti-inflammatory with IC50 (2.090 ± 0.49 μg/mL). Notably, it exhibits potent anticancer effects against human breast (T47D) and colon (Caco-2) cancer cell lines, (30.55 ± 1.19 and 31.34 ± 1.22 µg/mL respectively). The extract induces oxidative stress and apoptosis, as evidenced by elevated NO and MDA levels, alongside reduced SOD and CAT activities. Moreover, the downregulation of Nrf2/HMOX-1 and HIF-1α/VEGF pathways expression suggests intricate molecular mechanisms underlying its anticancer properties, potentially involving the modulation of oxidative stress and angiogenesis. These findings underscore the sea urchin (P. lividus) shell as a potent reservoir of bioactive constituents with promising applications in pharmaceutical research and offering new avenues for drug discovery.

A Comprehensive Review of the Antioxidant, Antimicrobial, and Therapeutic Efficacies of Black Cumin (Nigella sativa L.) Seed Oil and Its Thymoquinone

Black cumin (Nigella sativa L.) (family Ranunculaceae) is a largely utilized therapeutic herb worldwide. This comprehensive review discusses the pharmacological benefits of black cumin seed oil, focusing on its bioactive component thymoquinone (TQ). The review is structured as follows: First, we examine the antimicrobial properties of black cumin oil, followed by an analysis of its antioxidant capabilities. Finally, we explore its therapeutic potential, particularly in neurodegenerative diseases and COVID-19. Phytochemicals from N. sativa have exhibited potential for developing novel preventive and therapeutic strategies against jaundice, gastrointestinal disorders, skin diseases, anorexia, conjunctivitis, dyspepsia, intrinsic hemorrhage, amenorrhea, paralysis, anorexia, rheumatism, diabetes, hypertension, fever, influenza, eczema, asthma, cough, bronchitis, and headache. The broader spectrum of application for N. sativa and its essential bioactives have certainly enhanced the commercial value of this seed oil. TQ, a major constituent of black cumin seed oil, has numerous beneficial properties. Researchers have extensively studied black cumin seed oil and its major component, TQ. These studies have revealed a wide range of pharmacological properties, including anticancer, immunomodulatory, analgesic, antimicrobial, antidiabetic, and anti-inflammatory effects. Additionally, TQ has shown neuroprotective, spasmolytic, bronchodilatory, hepatoprotective, renoprotective, gastroprotective, and antioxidant activities.

Immunotherapy in Cervical Cancer: An Evolutionary Paradigm in Women's Reproductive Health

Cervical cancer is the fourth most common cause of morbidity and mortality in women. The major causative factor for cervical cancer is primary prolonged infection with human papillomavirus, along with secondary factors such as immunodeficiency, smoking, low socioeconomic standards, poor hygiene, and overuse of oral contraceptives. A grave need exists to practice novel strategies to overcome existing drawbacks of conventional therapy such as chemotherapy, radiation therapy, and surgery. Cancer immunotherapy works by strengthening the immune system of the host to combat against the cancerous cells. Immunotherapy in cervical cancer treatment has demonstrated long-lasting effects; however, the response to such therapies was nominal due to its prominent limitations such as immunosuppressive behavior of the tumor. Presently plethora of nanoplatforms such as polymeric nanoparticles, micelles, liposomes, and dendrimers are being maneuvered with cancer immunotherapy. The amalgamation of nanotechnology and immunotherapy in the treatment of cervical cancer is conceivable due to the mutual association between the tumor microenvironment and immunosurveillance. Safety concerns of nanoplatforms with immunotherapeutics such as toxicity, inflammation, and unwanted accumulation in tissues could be surmounted by surface modification methods. This review highlights the benefits of the amalgamation of nanotechnology and immunotherapy to improve shortcomings applicable to the conventional delivery of cancer treatment. We also aim to outline the nanoimmunotherapy sophistications and future translational avenues in this rapidly flourishing cancer treatment modality.

HDAC inhibition by Nigella sativa L. sprouts extract in hepatocellular carcinoma: an approach to study anti-cancer potential

A wide variety of natural products have been widely used in chemoprevention therapy because they have antioxidant, anti-inflammatory, and anticancer activity. In the present study, we shed light on the 5th day germinated sprouts of N. sativa seeds and evaluated them against HDAC inhibition and antioxidant activity. The extract from the seed and sprout was extracted and characterised by LC-MS/MS, FTIR, and NMR to reveal its chemical composition, especially thymol (THY) and thymoquinone (TQ). Hepatocellular carcinoma (HCC) is a global health concern as it is a major lifestyle disease. Hence, incorporating herbal-based therapeutic compounds into everyday routines has become an attractive alternative for preventing hepatic diseases. Histone deacetylase (HDAC) inhibition (HDACi) is emerging as a promising therapeutic strategy for managing various carcinomas including HCC. Therefore, the 5th day of N. sativa can be used as a potential anticancer agent by inhibiting HDAC activity, as it is reported to have an important role in the management of oxidative stress. The bioactive compound of N. sativa, i.e. thymoquinone, also showed a good binding affinity with the HDAC protein (3MAX) with a stable interaction in an in silico study as compared to the standard drug (Trichostatin A) and thymol.Communicated by Ramaswamy H. Sarma.

Molecular Mechanisms and Signaling Pathways Underlying the Therapeutic Potential of Thymoquinone Against Colorectal Cancer

Thymoquinone (TQ), a bioactive compound derived from Nigella sativa, has garnered significant attention for its potential as a natural anti-cancer agent, particularly in the context of colorectal cancer. This review provides a detailed synthesis of the current literature on the anti-cancer properties of TQ in colorectal cancer cells, exploring both in vitro and in vivo studies to elucidate its mechanisms of action. TQ effectively induces apoptosis, inhibits cell proliferation, and reduces metastasis in colorectal cancer cells by modulating key molecular pathways such as PI3K/AKT/mTOR, NF-κB, STAT3, and MAPK. It causes mitochondrial dysfunction and activates caspases, contributing to its pro-apoptotic effects. TQ also regulates EMT and targets cancer stem cells, reducing the likelihood of metastasis. Moreover, its antioxidant properties contribute to its protective role against cancer progression. While preclinical studies provide strong evidence of TQ's efficacy, further clinical studies are essential to establish its therapeutic potential in humans. This review underscores TQ's promising role as a natural agent with the potential to significantly improve colorectal cancer treatment outcomes.

Unleashing of cytotoxic effects of thymoquinone-bovine serum albumin nanoparticles on A549 lung cancer cells

This research examines the cytotoxic consequences of thymoquinone-loaded bovine serum albumin nanoparticles (TQ-BSA NPs) on the A549 lung cancer cell line. UV-visible (UV-Vis) spectroscopy, Fourier transform infrared spectrophotometer (FT-IR), scanning electron microscopy (SEM), and dynamic light scattering (DLS) were employed to verify the biogenic TQ-BSA NPs' size, shape, and distribution. UV-Vis spectrophotometry indicated peaks at 200-300 nm, 500-600 nm, and a prominent peak at 700-800 nm, confirming the presence of TQ-BSA NPs. The polydispersity index, as confirmed by DLS, indicated a solvent distribution in water, accompanied by a zeta potential value of 126.2 ± 46.8 mV. The average size of TQ-BSA NPs was confirmed to be 187 ± 8 nm by SEM. TQ-BSA NPs reduce colony formation in the A549 lung cancer cell line in a dose-dependent manner relative to the control group. Protein expression analysis indicated that TQ-BSA NPs promoted programmed cell death by increasing pro-apoptotic levels and decreasing anti-apoptotic levels. TQ-BSA NPs demonstrated inhibition of cancer cell proliferation and promotion of apoptosis and exhibited significant efficacy against cancer cells at low concentrations. As a result, they have the makings of a promising chemotherapeutic agent for low-dose, long-term administration.

Copper (II) increases anti-Proliferative activity of thymoquinone in colon cancer cells by increasing genotoxic, apoptotic, and reactive oxygen species generating effects

Thymoquinone is the main active compound derived from the essential oil of the Nigella sativa plant seed. While thymoquinone is an antioxidant, it has been reported in several studies that thymoquinone has dose-dependent pro-oxidant activity with the Fenton reaction in the presence of transition elements such as iron and copper. This study aimed to investigate cytotoxic, apoptotic, genotoxic, and reactive oxygen species (ROS) generating effects of thymoquinone treated with copper in colon cancer cells. HT-29 cells were treated with pro-oxidant-acting doses of thymoquinone alone and together with the non-toxic dose of Copper (II) Sulfate for 24 h. Cytotoxic, apoptotic, genotoxic, and ROS production activities were analyzed by MTT viability test, Acridine Orange/Ethidium Bromide (AO/EB) staining, alkaline single cell gel electrophoresis and H2DCF-DA assay, respectively. Viability results showed that thymoquinone and copper synergistically affect cancer cells, and DNA damage was increased with the synergic effect. The intracellular ROS was increased when thymoquinone and copper were applied together. Applying redox-active copper (II) with thymoquinone increases DNA damage, apoptosis, and cell death by increasing the amount of intracellular ROS through pro-oxidant activity. Treatments targeting copper-related pathways may open new therapeutic avenues for cancer treatment.

Natural Products and Derivatives Targeting Metabolic Reprogramming in Colorectal Cancer: A Comprehensive Review

Metabolic reprogramming is a critical pathogenesis of colorectal cancer (CRC), referring to metabolic disorders that cancer cells make in response to the stimulating pressure. Metabolic reprogramming induces changes in genetic material and promotes CRC progression and has been proven to be an efficient target of CRC. As natural products have garnered interest due to notable pharmacological effects and potential in counteracting chemoresistance, an increasing body of research is delving into the impact of these natural products on the metabolic reprogramming associated with CRC. In this review, we collected published data from the Web of Science and PubMed, covering the period from January 1980 to October 2023. This article focuses on five central facets of metabolic alterations in cancer cells, glucose metabolism, mitochondrial oxidative phosphorylation (OXPHOS), amino acid metabolism, fatty acid synthesis, and nucleotide metabolism, to provide an overview of recent advancements in natural product interventions targeting metabolic reprogramming in CRC. Our analysis underscores the potential of natural products in disrupting the metabolic pathways of CRC, suggesting promising therapeutic targets for CRC and expanding treatment options for metabolic-associated ailments.

Targeting Cancer Hallmarks Using Selected Food Bioactive Compounds: Potentials for Preventive and Therapeutic Strategies

Cancer continues to be a prominent issue in healthcare systems, resulting in approximately 9.9 million fatalities in 2020. It is the second most common cause of death after cardiovascular diseases. Although there are difficulties in treating cancer at both the genetic and phenotypic levels, many cancer patients seek supplementary and alternative medicines to cope with their illness, relieve symptoms, and reduce the side effects of cytotoxic drug therapy. Consequently, there is an increasing emphasis on studying natural products that have the potential to prevent or treat cancer. Cancer cells depend on multiple hallmarks to secure survival. These hallmarks include sustained proliferation, apoptosis inactivation, stimulation of angiogenesis, immune evasion, and altered metabolism. Several natural products from food were reported to target multiple cancer hallmarks and can be used as adjuvant interventions to augment conventional therapies. This review summarizes the main active ingredients in food that have anticancer activities with a comprehensive discussion of the mechanisms of action. Thymoquinone, allicin, resveratrol, parthenolide, Epigallocatechin gallate, and piperine are promising anticancer bioactive ingredients in food. Natural products discussed in this review provide a solid ground for researchers to provide effective anticancer functional food.

Mechanism, Formulation, and Efficacy Evaluation of Natural Products for Skin Pigmentation Treatment

Skin pigmentation typically arises from the excessive secretion and accumulation of melanin, resulting in a darker complexion compared to normal skin. Currently, the local application of chemical drugs is a first-line strategy for pigmentation disorders, but the safety and efficacy of drugs still cannot meet clinical treatment needs. For long-term and safe medication, researchers have paid attention to natural products with higher biocompatibility. This article begins by examining the pathogenesis and treatment approaches of skin pigmentation diseases and summarizes the research progress and mechanism of natural products with lightening or whitening effects that are clinically common or experimentally proven. Moreover, we outline the novel formulations of natural products in treating pigmentation disorders, including liposomes, nanoparticles, microemulsions, microneedles, and tocosomes. Finally, the pharmacodynamic evaluation methods in the study of pigmentation disorder were first systematically analyzed. In brief, this review aims to collect natural products for skin pigmentation treatment and investigate their formulation design and efficacy evaluation to provide insights for the development of new products for this complex skin disease.

Kalanchoe pinnata (Lam.) Pers. Leaf ethanolic extract exerts selective anticancer activity through ROS-induced apoptotic cell death in human cancer cell lines

BACKGROUND

The leaves of Kalanchoe pinnata (Lam.) Pers. (K. pinnata), a succulent plant native to tropical regions, are used as a medicinal alternative against cancer in several countries worldwide; however, its therapeutic potential to fight cancer has been little addressed. In this study, we analyzed the phytochemical content, antioxidant capacity, and selectivity of K. pinnata leaf ethanolic extract against different human cancer cell lines in vitro.

METHODOLOGY

This study subjected the ethanolic extract to enzymatic assays to quantify the phytochemical content (phenolics, flavonoids, and anthraquinones) and its radical scavenging and iron-reducing capacities. Also, the phytoconstituents and major phenolic compounds present in the extract's subfractions were identified by GC-MS, HPLC, and NMR. Human cancer (MCF-7, PC-3, HT-29) and normal colon (CoN) cell lines were treated with different concentrations of K. pinnata leaf ethanolic extract, and the changes in cell proliferation (sulforhodamine B assay), caspases activity (FITC-VAD-FMK reporter), mitochondrial membrane potential (MMP, rhodamine 123 assay), chromatin condensation/fragmentation (Hoechst 33342 stain), and ROS generation (DCFH2 probe assay) were assessed.

RESULTS

The results showed that the K. pinnata leaf ethanolic extract is rich in phytoconstituents with therapeutic potential, including phenols (quercetin and kaempferol), flavonoids, fatty acid esters (34.6% of the total composition), 1- triacontanol and sterols (ergosterol and stigmasterol, 15.4% of the total composition); however, it presents a poor content of antioxidant molecules (IC50 = 27.6 mg/mL for H2O2 scavenging activity vs. 2.86 mg/mL in the case of Trolox). Notably, the extract inhibited cell proliferation and reduced MMP in all human cell lines tested but showed selectivity for HT-29 colon cancer cells compared to CoN normal cells (SI = 8.4). Furthermore, ROS generation, caspase activity, and chromatin condensation/fragmentation were augmented significantly in cancer-derived cell lines, indicating a selective cytotoxic effect.

CONCLUSION

These findings reveal that the K. pinnata leaf ethanolic extract contains several bioactive molecules with therapeutic potential, capable of displaying selective cytotoxicity in different human cancer cell lines.

Novel thymohydroquinone gallate derivative loaded ligand modified quantum dots as pH-sensitive multi-modal theragnostic agent for cancer treatment

BACKGROUND

Nanomedicine, as the combination of radiopharmaceutical and nanocarrier (QDs), is developed for treating cancer. Gallic acid is antimutagenic, anti-inflammatory, and anti-carcinogenic. Typical retention time of gallic acid is approximately 4 to 8 h. To increase the retention time gallic acid is converted to prodrug by adding lipophilic moieties, encapsulating in lipophilic nanoparticles, or liposome formation. Similarly, thymoquinone is powerful antioxidant, anti-apoptotic, and anti-inflammatory effect, with reduced DNA damage.

METHODS

In this study, a hydrophilic drug (gallic acid) is chemically linked to the hydrophobic drug (thymohydroquinone) to overcome the limitations of co-delivery of drugs. Thymohydroquinone (THQG) as the combination of gallic acid (GA) and thymoquinone (THQ) is loaded onto the PEI functionalized antimonene quantum dots (AM-QDs) and characterized by FTIR, UV-visible spectroscopy, X-ray powder diffraction, Zeta sizer, SEM and AFM, in-vitro and in-vivo assay, and hemolysis.

RESULTS

The calculated drug loading efficiency is 90 %. Drug release study suggests the drug combination is pH sensitive and it can encounters acidic pH, releasing the drug from the nanocarrier. The drug and drug-loaded nanocarrier possesses low cytotoxicity and cell viability on MCF-7 and Cal-27 cell lines. The proposed drug delivery system is radiolabeled with Iodine-131 (131I) and Technetium (99mTc) and its deposition in various organs of rats' bodies is examined by SPECT-CT and gamma camera. Hemolytic activity of 2, 4, 6, and 8 μg/mL is 1.78, 4.16, 9.77, and 15.79 %, respectively, reflecting low levels of hemolysis. The system also sustains oxidative stress in cells and environment, decreasing ROS production to shield cells and keep them healthy.

CONCLUSIONS

The results of this study suggest that the proposed drug carrier system can be used as a multi-modal theragnostic agent in cancer treatment.

Thymoquinone Nanoparticles (TQ-NPs) in Kidney Toxicity Induced by Ehrlich Ascites Carcinoma (EAC): An In Vivo Study

Background

Cisplatin (Cis) is potent chemotherapy used to treating already many different types of cancer; however, it is found to correlate with nephrotoxicity and other adverse health consequences. Thymoquinone (TQ) is an antioxidant and anti-inflammatory molecule that may defend against the consequences of different chemotherapies. Thymoquinone uses, although, are negatively impacted by its weak solubility and inadequate biological availability.

Objectives

This investigation examined the efficacy of a new nanoparticle (NP) absorbing TQ in an Ehrlich Ascites Carcinoma (EAC) mice model to address its low solubility, enhance its bioavailability, and protect against Cis-induced nephrotoxicity.

Methods

Following 4 treatment groups were included in this research: (1) control, (2) EAC, (3) EAC + Cis + Thymoquinone nanoparticle (TQ-NP) treated, and (4) EAC + Cis-treated.

Results

The study revealed that TQ-NP was efficacious in avoiding Cis-induced kidney problems in EAC mice, as well as restoring kidney function and pathology. Thymoquinone nanoparticle considerably reduced Cis-induced oxidative damage in renal tissue by augmenting antioxidant levels. According to tumor weight and histological investigation results, TQ-NP did not impair Cis's anticancer efficacy.

Conclusion

Thymoquinone nanoparticle might be used as a potential drug along with Cis anticancer therapy to reduce nephrotoxicity and other side effects while maintaining Cis anticancer properties.

A bioanalytical assay for estimation of thymoquinone in rats cerebrospinal fluid and brain tissues of nasally administrated thymoquinone loaded lipo-polymeric nanoshells and its pharmacokinetic profiling

Thymoquinone (TH) has been one of the major phytochemical used in the treatment of cancers since long time, especially in the management of glioblastoma multiforme (GBM). The formulation of lipo-polymeric nanoshells (LPNs) and their nasal delivery are fascinating approaches for overcoming the drawbacks of low solubility and poor bioavailability of TH. Hence targeting LPNs to the brain requires a validated bioanalytical method for the assessment of TH concentration in Cerebrospinal fluid (CSF) and brain tissue homogenates (BTH). Therefore, the current work focuses on the development and validation of high-performance liquid chromatography (HPLC) method in CSF by employing nasal simulated fluid (NSF) as one of the major components of the mobile phase. The developed method was checked for linearity in the range of 0.05 to 1.6 μg/mL, having an r2 value of 0.999 with mean % recovery >95% and % RSD values below <2.0%. The developed method gave a clear separation of TH at 6.021 ± 0.17 min with an internal standard at 4.102 ± 0.09 min and a CSF spike at 2.170 ± 0.12 min. The developed method assisted in determining the in-vitro and in-vivo drug release study of LPNs, pharmacokinetic profiling, qualitative in-vivo brain uptake study, in-vitro cellular uptake, and generating stability data of formulated LPNs proposed for intranasal administration in rats.

Investigation of reno-protective efficacy of thymoquinone in a unilateral hydronephrosis model

We aimed to evaluate the effects of the antioxidant thymoquinone on treated and untreated kidneys on histological and oxidative parameters as well as Kidney Injury Molecule (KIM-1) levels in an experimental unilateral ureteropelvic junction obstruction (UPJO) with resultant hydronephrosis (HN) model. In adherence to the Animal research: reporting of in vivo exepriments guidelines, 34 male Wistar rats were randomly divided into four groups which were named accordingly: "CO" (corn oil), "TQ" (thymoquinone and corn oil), "HNCO" (UPJO-HN and corn oil), "HNTQ" (UPJO-HN, thymoquinone and corn oil). Histologically, pelvic epithelial damage, glomerular shrinkage and sclerosis, tubular damage, interstitial edema-inflammation-fibrosis (IEIF), and vascular congestion were assessed. Biochemically, malondialdehyde (MDA), superoxide dismutase (SOD), glutathione reductase (GR) and KIM-1 levels were assessed. Macroscopic HN developed in all obstructed kidneys. Ipsilateral obstructed kidneys deteriorated in all histological parameters. Thymoquinone attenuated glomerular shrinkage and sclerosis alterations but increased vascular congestion. Contralateral non-obstructed kidneys also showed histological deterioration. Thymoquinone had beneficial effects in terms of IEIF presence in contralateral kidneys but it increased vascular congestion. MDA and SOD results were inconclusive. UPJO caused decreased GR levels in the ipsilateral kidneys but not in the contralateral ones. This effect was not ameliorated by thymoquinone treatment. KIM-1 levels were increased in ipsilateral obstructed kidneys with a lower level in HNTQ group than in HNCO. KIM-1 level of the ipsilateral HNTQ group was higher than in both non-obstructed ipsilateral kidney groups. The effect of thymoquinone in ameliorating bilaterally observed histological alterations was limited and controversial. Oxidative damage detected by GR measurements was not prevented by thymoquinone. Thymoquinone partially decreased the damage as evidenced by reduced KIM-1 levels in thymoquinone-treated obstructed kidneys.

Aptamers for the Delivery of Plant-Based Compounds: A Review

Natural compounds have a high potential for the treatment of various conditions, including infections, inflammatory diseases, and cancer. However, they usually present poor pharmacokinetics, low specificity, and even toxicity, which limits their use. Therefore, targeted drug delivery systems, typically composed of a carrier and a targeting ligand, can enhance natural product selectivity and effectiveness. Notably, aptamers-short RNA or single-stranded DNA molecules-have gained attention as promising ligands in targeted drug delivery since they are simple to synthesize and modify, and they present high tissue permeability, stability, and a wide array of available targets. The combination of natural products, namely plant-based compounds, with a drug delivery system utilizing aptamers as targeting agents represents an emerging strategy that has the potential to broaden its applications. This review discusses the potential of aptamers as targeting agents in the delivery of natural compounds, as well as new trends and developments in their utilization in the field of medicine.

Exploring Tumor-Promoting Qualities of Cancer-Associated Fibroblasts and Innovative Drug Discovery Strategies With Emphasis on Thymoquinone

Tumor epithelial development and chemoresistance are highly promoted by the tumor microenvironment (TME), which is mostly made up of the cancer stroma. This is due to several causes. Cancer-associated fibroblasts (CAFs) stand out among them as being essential for the promotion of tumors. Understanding the fibroblastic population within a single tumor is made more challenging by the undeniable heterogeneity within it, even though particular stromal alterations are still up for debate. Numerous chemical signals released by tumors improve the connections between heterotypic fibroblasts and CAFs, promoting the spread of cancer. It becomes essential to have a thorough understanding of this complex microenvironment to effectively prevent solid tumor growth. Important new insights into the role of CAFs in the TME have been revealed by recent studies. The objective of this review is to carefully investigate the relationship between CAFs in tumors and plant secondary metabolites, with a focus on thymoquinone (TQ). The literature published between 2010 and 2023 was searched in PubMed and Google Scholar with keywords such as TQ, TME, cancer-associated fibroblasts, mechanism of action, and flavonoids. The results showed a wealth of data substantiating the activity of plant secondary metabolites, particularly TQ's involvement in blocking CAF operations. Scrutinized research also clarified the wider effect of flavonoids on pathways related to cancer. The present study highlights the complex dynamics of the TME and emphasizes the critical role of CAFs. It also examines the possible interventions provided by secondary metabolites found in plants, with TQ playing a vital role in regulating CAF function based on recent literature.

Thymoquinone: A Promising Therapeutic Agent for the Treatment of Colorectal Cancer

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers and is responsible for approximately one million deaths each year. The current standard of care is surgical resection of the lesion and chemotherapy with 5-fluorouracil (5-FU). However, of concern is the increasing incidence in an increasingly younger patient population and the ability of CRC cells to develop resistance to 5-FU. In this review, we discuss the effects of thymoquinone (TQ), one of the main bioactive components of Nigella sativa seeds, on CRC, with a particular focus on the use of TQ in combination therapy with other chemotherapeutic agents. TQ exhibits anti-CRC activity by inducing a proapoptotic effect and inhibiting proliferation, primarily through its effect on the regulation of signaling pathways crucial for tumor progression and oxidative stress. TQ can be used synergistically with chemotherapeutic agents to enhance their anticancer effects and to influence the expression of signaling pathways and other genes important in cancer development. These data appear to be most relevant for co-treatment with 5-FU. We believe that TQ is a suitable candidate for consideration in the chemoprevention and adjuvant therapy for CRC, but further studies, including clinical trials, are needed to confirm its safety and efficacy in the treatment of cancer.

Protective potential of thymoquinone against cadmium, arsenic, and lead toxicity: A short review with emphasis on oxidative pathways

Heavy metals are among the most important environmental pollutions used in various industries. Their extensive use has increased human susceptibility to different chronic diseases. Toxic metal exposure, especially cadmium, arsenic, and lead, causes oxidative damages, mitochondrial dysfunction, and genetic and epigenetic modifications. Meanwhile, thymoquinone (TQ) is an effective component of Nigella sativa oil that plays an important role in preventing the destructive effects of heavy metals. The present review discusses how TQ can protect various tissues against oxidative damage of heavy metals. This review is based on the research reported about the protective effects of TQ in the toxicity of heavy metals, approximately the last 10 years (2010-2021). Scientific databases, including Scopus, Web of Science, and PubMed, were searched using the following keywords either alone or in combination: cadmium, arsenic, lead, TQ, and oxidative stress. TQ, as a potent antioxidant, can distribute to cellular compartments and prevent oxidative damage of toxic metals. However, depending on the type of toxic metal and the carrier system used to release TQ in biological systems, its therapeutic dosage range may be varied.

Exploring the Potential of Thymoquinone-Stabilized Selenium Nanoparticles: In HEC1B Endometrial Cancer Cells Revealing Enhanced Anticancer Efficacy

The aim of this research is to examine the potential anticancer properties of thymoquinone (TQ)-encapsulated selenium nanoparticles (TQ-SeNPs) in HEC1B endometrial carcinoma cells. TQ-SeNPs were synthesized, and their size, morphology, and elemental analysis were characterized. Morphological changes were examined by using scanning electron microscopy (SEM). The cytotoxicity and viability of nanothymoquinone were assessed by the XTT (2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5 carboxanilide) assay. Gene expressions and protein levels of the mitogen-activated protein kinase (MAPK) signaling pathway were analyzed by real-time PCR and enzyme-linked immunosorbent assay (ELISA), respectively. The decrease in the viability of HEC1B endometrial carcinoma cells was observed in a time- and dose-dependent manner. HEC-1B cells were treated with TQ-SeNP at 40-640 μg/mL concentrations and time intervals, and their viability was assessed by XTT assay. IC50 doses of TQ-SeNP in HEC1B cells were detected as 526.45 μg/mL at 48th hour. ELISA indicated that TQ-SeNP treatment reduced the level of p38 MAPK. ERK2, MEK2, and NFKB (p65) mRNA expressions were decreased in the dose group administered TQ-SeNP at the 48th hour compared to that in the control group. However, it was not significant. The novel nanoparticle showed an antiproliferative effect in endometrial cancer cells. However, further studies are needed to increase the anticancer activity of the cell in the TQ-SeNP interaction.

Thymoquinone protects against 5-Fluorouracil-induced mucositis by NF-κβ and HIF-1 mechanisms in mice

Mucositis is among the most common side effects of 5-Fluorouracil (5-FU) and other cancer therapeutic drugs. Thymoquinone (TQ), a bioactive constituent extracted from Nigella sativa, has antioxidant and anti-inflammatory properties and can modify acute gastrointestinal injury. To investigate the effects of TQ on mucositis induced by 5-FU, studied animals were divided into four groups: control, 5-FU unit dose (300 mg/kg) to cause oral and intestinal mucositis (OM and IM), TQ (2.5 mg/kg) and TQ (2.5 mg/kg) plus 5-FU. Due to The molecular mechanisms, it was confirmed that the expression of NF-κβ and HIF-1 increases in OM. The serum levels of malondialdehyde (MDA), catalase (CAT), and superoxide dismutase (SOD), as well as pathological parameters, were assessed. Based on our results, the nuclear factor-kappa β gene expression in the tongue was downregulated significantly in the 5-FU + TQ compared to the 5-FU. TQ treatment can diminish MDA, and a reduction in oxidative stress was shown. TQ could also reduce the severity of tissue destruction and damaging effects induced by 5-FU on the tongue and intestine. We also observed lower villus length and width in the intestine of the 5-FU group compared to the control group. According to our research's pathological, biochemical, and molecular results, treatment with TQ as an anti-inflammatory and antioxidant compound may be the potential to improve and treat 5-FU-induced OM and IM, and TQ could be used against cancer treatment drugs and exhibit fewer adverse effects.

Anticancer activity of thymoquinone against breast cancer cells: Mechanisms of action and delivery approaches

The rising incidence of breast cancer has been a significant source of concern in the medical community. Regarding the adverse effects and consequences of current treatments, cancers' health, and socio-economical aspects have become more complicated, leaving research aimed at improved or new treatments on top priority. Medicinal herbs contain multitarget compounds that can control cancer development and advancement. Owing to Nigella Sativa's elements, it can treat many disorders. Thymoquinone (TQ) is a natural chemical derived from the black seeds of Nigella sativa Linn proved to have anti-cancer and anti-inflammatory properties. TQ interferes in a broad spectrum of tumorigenic procedures and inhibits carcinogenesis, malignant development, invasion, migration, and angiogenesis owing to its multitargeting ability. It effectively facilitates miR-34a up-regulation, regulates the p53-dependent pathway, and suppresses Rac1 expression. TQ promotes apoptosis and controls the expression of pro- and anti-apoptotic genes. It has also been shown to diminish the phosphorylation of NF-B and IKK and decrease the metastasis and ERK1/2 and PI3K activity. We discuss TQ's cytotoxic effects for breast cancer treatment with a deep look at the relevant stimulatory or inhibitory signaling pathways. This review discusses the various forms of polymeric and non-polymeric nanocarriers (NC) and the encapsulation of TQ for increasing oral bioavailability and enhanced in vitro and in vivo efficacy of TQ-combined treatment with different chemotherapeutic agents against various breast cancer cell lines. This study can be useful to a broad scientific community, comprising pharmaceutical and biological scientists, as well as clinical investigators.

Thymoquinone inhibits lung cancer stem cell properties via triggering YAP degradation

Due to the characteristics of high recurrence and metastasis, it is still difficult to cure lung cancer. Cancer stem cells (CSCs) are a group of tumor cells with self-renewal ability and differentiation potential, which are responsible for lung cancer recurrence. Therefore, targeting CSCs may provide a new strategy for lung cancer treatment. Thymoquinone (TQ), the main active ingredient isolated from black seed oil, has shown significant anti-cancer effects in various cancers. However, the effect of TQ on lung cancer stem cells (LCSCs) has never been clarified. In the present study, we successfully separated and enriched lung cancer tumorsphere cells. Our data showed that TQ significantly inhibited the stem-like properties of LCSCs. In addition, we found TQ promoted Yes-associated protein (YAP) phosphorylation and ubiquitination, and the inhibitory effects of TQ on LCSCs could be enhanced by silencing YAP. Taken together, these results suggest that TQ, functions by targeting YAP, may be a potential therapeutic agent against lung cancer.

John M, Alhiyari Y. Nigella sativa oil mitigates xerostomia and preserves salivary function in radiotherapy-treated mice

Objective

This study aimed to assess if Nigella sativa oil (NSO), a health supplement containing thymoquinone as a major component, can act as a protective agent in salivary gland stem cells following radiotherapy (RT) damage.

Methods

Forty, 10-week-old, male C3H/HeJ mice were randomized to four experimental groups: sham RT + H2O gavage (control) (N = 4); 15 Gy RT + H2O gavage (N = 12); sham RT + NSO gavage (N = 12); and 15 Gy RT + NSO gavage (N = 12). Weight changes, saliva production, and salivary gland histopathologic staining were recorded for each group over the course of the experiment.

Results

All mice in the sham RT + H2O gavage and sham RT + NSO gavage groups demonstrated 100% 60-day survival. RT + H2O compared to RT + NSO gavaged mice were significantly underweight by an average of 6.4 g (p < .001). Salivary output showed significant decline in RT + H2O gavaged mice at days 3 and 16, whereas salivary output in RT + NSO during these same time periods was comparable to the control. At day 60, all mice that survived recovered salivary function regardless of their treatment arm. Salivary specimens from the RT + NSO gavage group demonstrated early signs of recovery of Kr 5+ salivary gland stem cells in both submandibular and sublingual glands at day 16 with complete recovery by day 60, marked by strong histopathologic staining, whereas the RT + H2O gavage group did not recover as effectively.

Conclusion

NSO may help preserve salivary function in mice treated with RT and may mitigate xerostomia by accelerating the recovery of salivary gland stem cells.

Level of evidence

Not applicable.

John M. Anticancer effects of thymoquinone in head and neck squamous cell carcinoma: A scoping review

Objective

Thymoquinone (TQ), the active constituent of Nigella sativa, has been shown to have anticancer effects in head and neck squamous cell carcinoma (HNSCC). This review aims to outline the properties of TQ, the known drivers in HNSCC formation, and summarize the anticancer effects of TQ in SCC.

Data Sources

Three databases (PubMed, Embase, and Google Scholar) were queried for the key words "thymoquinone squamous cell carcinoma."

Review Methods

Publications that were not original research and publications that did not have full-text available for review were excluded.

Results

Sixteen research articles met the inclusion criteria. Our review demonstrates that TQ-induced cytotoxicity is associated with increased expression and activity of the tumor suppressor p53, proapoptotic proteins Bax and caspases, as well as decreased expression and activity of antiapoptotic proteins Bcl-2 and Mdm2. Additionally, TQ modulates cell-survival pathways such as the PI3k/Akt pathway. TQ synergizes with therapeutics including cisplatin and radiation. Early TQ administration may prevent carcinogenesis via upregulation of antioxidant enzymes, and TQ administration in the presence of cancer can result in disease mitigation via induction of oxidative stress.

Conclusion

TQ acts as an upregulator of proapoptotic pathways and downregulator of antiapoptotic pathways, modulates the oxidative stress balance in tumor development, and works synergistically alongside other chemotherapeutics to increase cytotoxicity. TQ has the potential to prevent carcinogenesis in patients who are at high-risk for SCC and adjuvant treatment for SCC patients undergoing conventional treatments. Future studies should aim to identify specific populations in which TQ's effects would be the most beneficial.

Level of Evidence

Not available.

Synergism Antiproliferative Effects of Apigenin and Naringenin in NSCLC Cells

Non-small cell lung cancer (NSCLC) is one of the leading cancer killers. Apigenin (Api) and Naringenin (Nar) are natural bioactive substances obtained in various vegetables and fruits, possessing anti-tumor effects across multiple studies. This study investigated the latent synergistic antiproliferative functions of Api and Nar in A549 and H1299 NSCLC cells. Cell viability was determined after incubating with different concentrations of Api, Nar, or the combination of Api and Nar (CoAN) for 24 h. Analysis using the CompuSyn software revealed that the CI value of each combined dose was < 1, depicting that the two drugs had a synergistic inhibitory effect. The CoAN (A:N = 3:2) group with the lowest CI value was selected for subsequent experiments. The IC₅₀ of CoAN (A:N = 3:2) was used to determine the cell cycle, the expression ratio of Bax to Bcl2, Caspase 3 activity, and mitochondrial function to assess oxidative stress and apoptosis. The results established that CoAN treatment caused significant cytotoxicity with cell cycle arrest at G2/M phases. Furthermore, CoAN significantly enhanced mitochondria dysfunction, elevated oxidative stress, and activated the apoptotic pathway versus Api or Nar alone groups. Thus, the CoAN chemotherapy approach is promising and deserves further research.

Thymoquinone effect on the Dictyostelium discoideum model correlates with functional roles for glutathione S-transferases in eukaryotic proliferation, chemotaxis, and development

An increasing body of literature demonstrates the therapeutic relevance of polyphenols in eukaryotic cell and animal model studies. The phase II glutathione S-transferases (GST) show differential responses to thymoquinone, a major bioactive polyphenol constituent of the black seed, Nigella sativa. Beyond antioxidant defense, GSTs may act in non-enzymatic capacities to effect cell cycle, motility, and differentiation. Here, we report the impact of thymoquinone on the life cycle of the eukaryotic model Dictyostelium discoideum and accompanying profiles of its GST-alpha (DdGSTA) enzyme activity and isozyme expression. In silico molecular modeling revealed strong interaction(s) between thymoquinone and DdGSTA2 and DdGSTA3 isozymes that correlated with in vivo, dose-dependent inhibition of cell proliferation of amoebae at 24, 48, and 72hr. Similarly, cytosolic DdGST enzyme activity (CDNB activity) was also responsive to different thymoquinone concentrations. Thymoquinone generally reduced expression of DdGSTA2 and DdGSTA3 isozymes in proliferating cells, however differential expression of the isozymes occurred during starvation. Thymoquinone effectively reduced early-stage aggregation of starved amoeba, accompanied by increased reactive oxygen species and altered expression of tubulin and contact site A (gp80), which resulted in reduced morphogenesis and fruiting body formation. These observations reveal that thymoquinone can impact signaling mechanisms that regulate proliferation and development in D. discoideum.

Hepatic Response to the Interaction Between Thymoquinone and Iron-Dextran: an In Vitro and In Vivo Study

Iron is one of the most important essential elements for cell function. However, iron overload can exert destructive effects on various tissues, especially the liver. The present study was designed to evaluate the effect of thymoquinone (TQ) on hepatotoxicity induced by iron-overload in in vitro and mouse model. After in vitro studies, thirty mice were divided into five groups, six each. Group 1 received normal saline. Group 2 received five doses of iron dextran (i.p; 100 mg/kg, one dose every 2 days). Group 3 received TQ (orally, 2 mg/kg/day). Groups 4 and 5 were administrated iron dextran saline (i.p; 100 mg/kg, one dose every 2 days) following treatment with 0.5 and 2 mg/kg/day of TQ, respectively. Based on the findings of the DPPH experiment, although TQ has significant anti-radical potential, at a safe dose of 15 × 10⁺³ nM, it reduced the IC₅₀ of iron dextran on HepG2 cells by about 25%, in in vitro. Following administration of low-dose TQ (0.5 mg/kg), a significant improvement was observed in serum hepatic enzymes activity and hepatic lipid peroxidation compared to iron dextran. However, administration of TQ-high dose (2 mg/kg) led to decrease antioxidant defense alongside increased serum hepatic enzymes and pathological damages in iron dextran-treated animals. Due to the different efficacy of TQ in treatment groups, it seems that the TQ therapeutic index is low and does not have significant safety in the iron overload status.

Advances in research on the relationship between thymoquinone and pancreatic cancer

Pancreatic cancer has one of the worst prognoses among the most common cancers in the world. Its characteristics include a high rate of metastasis and chemotherapeutic resistance, which present major challenges to the medical community. The potential anticancer effects of thymoquinone (TQ), which is the main bioactive compound of the black seeds of the Nigella sativa plant, have recently received widespread attention for their potential use in treating pancreatic cancer. TQ can inhibit cell proliferation, promote cancer cell apoptosis, inhibit cell invasion and metastasis, enhance chemotherapeutic sensitivity, inhibit angiogenesis, and exert anti-inflammatory effects. These anticancer effects predominantly involve the nuclear factor (NF)-κB, phosphoinositide 3 kinase (PI3K)/Akt, Notch, transforming growth factor (TGF)-β, c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) signaling pathways as well as the regulation of the cell cycle, matrix metallopeptidase (MMP)-9 expression, and pyruvate kinase isozyme type M2 (PKM2) activity. TQ regulates the occurrence and development of pancreatic cancer at multiple levels and through multiple targets that communicate with each other. In this review, we summarize and discuss the analogs and carriers of TQ that have been developed in recent years. Given its multilevel anticancer effects, TQ may become a new therapeutic drug for treating pancreatic cancer in the future. This review presents a brief introduction to the research that has been conducted on TQ in relation to pancreatic cancer to provide a theoretical basis for future studies on the topic.

Thymoquinone induces apoptosis in temozolomide-resistant glioblastoma cells via the p38 mitogen-activated protein kinase signaling pathway

Temozolomide (TMZ) can cross the blood-brain barrier (BBB) and deliver methyl groups to the purine (guanine) bases of DNA, leading to mispairing during DNA replication and subsequent cell death. However, increased expression of the repair enzyme methyl guanine methyltransferase (MGMT), which removes methyl groups from purine bases, counteracts methylation by TMZ. We evaluated the anticancer potential of thymoquinone (TQ), a hydrophobic flavonoid that inhibits resistance and induces apoptosis in various cancer cells, both in vitro and in vivo. In vitro experiments showed that compared with the Hs683 and M059J cell lines, U251 cells were more sensitive to TMZ. Compared to U251 cells, U251R cells, a TMZ drug-resistant strain established in this study, are characterized by increased expression of phosphorylated extracellular signal-regulated kinase (p-ERK) and MGMT. TQ treatments induced apoptosis in all cell lines. The p38 mitogen-activated protein kinase signal pathway was mainly activated in U251 and U251R cells; however, p-ERK and MGMT upregulation could not suppress TQ effects. Furthermore, si-p38 pretreatment of U251R cells in TQ treatments inhibited cell apoptosis. We speculate that TQ contributed to the phosphorylation and activation of p38, but not of ERK-induced apoptosis (irrespective of TMZ resistance). In vivo, U251R-derived tumors subcutaneously inoculated in nude mice exhibited significant tumor volume reduction after TQ or TQ + TMZ cotreatments. High-performance liquid chromatography assay confirmed the presence of TQ in murine brain tissues. Our findings demonstrate that TQ can effectively cross the BBB and function alone or in combination with TMZ to treat glioblastoma.

Anticancer Effects of Thymoquinone through the Antioxidant Activity, Upregulation of Nrf2, and Downregulation of PD-L1 in Triple-Negative Breast Cancer Cells

The variety of therapies available for treating and preventing triple-negative breast cancer (TNBC) is constrained by the absence of progesterone receptors, estrogen receptors, and human epidermal growth factor receptor 2. Nrf2 (nuclear factor-erythroid 2-related factor), and PD-L1 (program cell death ligand 1), a downstream signaling target, have a strong correlation to oxidative stress and inflammation, major factors in the development and progression of TNBC. In this study, the genetically distinct MDA-MB-231 and MDA-MB-468 TNBC cells were treated with the natural component thymoquinone (TQ). The results show that TQ exhibits considerable antioxidant activity and decreases the generation of H₂O₂, at the same time increasing catalase (CAT) activity, superoxide dismutase (SOD) enzyme, and glutathione (GSH). Additionally, the results show that TQ treatment increased the levels of the different genes involved in the oxidative stress-antioxidant defense system PRNP, NQO1, and GCLM in both cell lines with significant large-fold change in MDA-MB-468 cells (+157.65 vs. +1.7, +48.87 vs. +2.63 and +4.78 vs. +2.17), respectively. Nrf2 mRNA and protein expression were also significantly increased in TQ-treated TNBC cells despite being higher in MDA-MB-468 cells (6.67 vs. 4.06). Meanwhile, TQ administration increased mRNA levels while decreasing PD-L1 protein expression in both cell lines. In conclusion, TQ modifies the expression of multiple oxidative-stress-antioxidant system genes, ROS, antioxidant enzymes, Nrf2, and PD-L1 protein, pointing to the therapeutic potential and chemopreventive utilization of TQ in TNBC.

Antioxidants in brain tumors: current therapeutic significance and future prospects

Brain cancer is regarded among the deadliest forms of cancer worldwide. The distinct tumor microenvironment and inherent characteristics of brain tumor cells virtually render them resistant to the majority of conventional and advanced therapies. Oxidative stress (OS) is a key disruptor of normal brain homeostasis and is involved in carcinogenesis of different forms of brain cancers. Thus, antioxidants may inhibit tumorigenesis by preventing OS induced by various oncogenic factors. Antioxidants are hypothesized to inhibit cancer initiation by endorsing DNA repair and suppressing cancer progression by creating an energy crisis for preneoplastic cells, resulting in antiproliferative effects. These effects are referred to as chemopreventive effects mediated by an antioxidant mechanism. In addition, antioxidants minimize chemotherapy-induced nonspecific organ toxicity and prolong survival. Antioxidants also support the prooxidant chemistry that demonstrate chemotherapeutic potential, particularly at high or pharmacological doses and trigger OS by promoting free radical production, which is essential for activating cell death pathways. A growing body of evidence also revealed the roles of exogenous antioxidants as adjuvants and their ability to reverse chemoresistance. In this review, we explain the influences of different exogenous and endogenous antioxidants on brain cancers with reference to their chemopreventive and chemotherapeutic roles. The role of antioxidants on metabolic reprogramming and their influence on downstream signaling events induced by tumor suppressor gene mutations are critically discussed. Finally, the review hypothesized that both pro- and antioxidant roles are involved in the anticancer mechanisms of the antioxidant molecules by killing neoplastic cells and inhibiting tumor recurrence followed by conventional cancer treatments. The requirements of pro- and antioxidant effects of exogenous antioxidants in brain tumor treatment under different conditions are critically discussed along with the reasons behind the conflicting outcomes in different reports. Finally, we also mention the influencing factors that regulate the pharmacology of the exogenous antioxidants in brain cancer treatment. In conclusion, to achieve consistent clinical outcomes with antioxidant treatments in brain cancers, rigorous mechanistic studies are required with respect to the types, forms, and stages of brain tumors. The concomitant treatment regimens also need adequate consideration.

Chemopreventive Efficacy of Thymoquinone in Chemically Induced Urinary Bladder Carcinogenesis in Rat

The effects of thymoquinone (TQ) in a carcinogen-based models of urinary bladder cancer were evaluated, using 45 male rats in five groups. In negative control ( $n=10$ ), only tap water was given. In positive control ( $n=10$ ), the rats received 0.05% N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) in drinking water for 9 weeks. In preventive groups with 25 mg/kg ( $n=10$ ) and 50 mg/kg ( $n=10$ ), oral TQ was concurrently given with 0.05% BBN for 9 weeks and continued for one more week after cessation of BBN. Preventive-treatment group ( $n=5$ ) received 50 mg/kg TQ orally for 20 weeks. Five rats from each group were sequentially sacrificed in two phases: the induction phase at 12th week (except the last group) and the rest in postinduction phase at 20th week. The bladders were examined macroscopically for lesion formation, and the masses were submitted for histopathological evaluation. Markers for total oxidant status (TOS), inflammation (nuclear factor kappa B (NF-κB)), and angiogenesis (vascular endothelial growth factor (VEGF)) were also assessed. There was a reduced number of bladder lesions in the TQ groups versus the carcinogen group at both phases. Histopathological findings demonstrated a significant improvement in the abnormal morphological changes in the urothelium of the TQ-treated groups. Thymoquinone exerted a significant antioxidant and anti-inflammatory effect by a decrease in serum level of TOS and NF-κB at week 12 which was maintained low in phase two at week 20. The serum level of VEGF was also alleviated in the induction phase at week 12 and maintained low in postinduction period. In TQ preventive-treatment approach, a nonsignificant elevation of serum level of TOS and NF-κB and slight reduction in VEGF were observed at the end of the experiment. These data suggest that TQ may be effective in preventing bladder carcinogenesis, and the suggested mechanisms might be related to antioxidant, prooxidant, and anti-inflammatory properties of TQ.

Effects of Thymoquinone on Adipocyte Differentiation in Human Adipose-Derived Stem Cells

Inhibition of adipocyte differentiation would be a key strategy to control obesity. Human adipose tissue-derived stem cells (ADSCs) are a promising tool for adipocyte differentiation research. Thymoquinone (TQ) as a potent antioxidant molecule may inhibit adipocyte differentiation. Herein, we aim to investigate the inhibitory effect of TQ on lipid differentiation in ADSCs. Quantification of cell surface markers was used by Flow-Cytometry and the effect of TQ on cell viability was assessed using the AlamarBlue test. ADSCs were subjected to induction of differentiation in the presence of non-cytotoxic concentrations of TQ (6.25, 12.5 and 25 μg/mL). Lipid accumulation was assessed using the Oil-Red O staining technique. Moreover, the expression of PPARγ (Peroxisome proliferator-activated receptor-γ) and FAS (Fatty Acid Synthetase) proteins was evaluated using Western blotting. Flow-cytometry demonstrated the expression of CD44, CD90, and CD73 as mesenchymal stem cell markers on the cell surface. At concentrations ≤100 μg/mL of TQ, no significant difference in cell viability was observed compared to the control. Lipid accumulation in ADSCs significantly decreased at 25 μg/mL (P < 0.001) and 12.5 μg/mL (P < 0.01) of TQ. The findings of the qualitative examination of Lipid Droplets also confirmed these results. Western-blot showed that TQ at 12.5 (p < 0.05) and 25 μg/mL (p < 0.01) reduced FAS/β-actin ratio compared to the positive group. TQ also decreased the expression of PPARγ at 6.25 μg/mL but not at higher concentrations. In conclusion, TQ may reduce differentiation of fat stem cells into fat cells through inhibition of the expression of PPARγ and FAS proteins and might be a potential anti-obesity compound.

Combination Anticancer Therapies Using Selected Phytochemicals

Cancer is still one of the most widespread diseases globally, it is considered a vital health challenge worldwide and one of the main barriers to long life expectancy. Due to the potential toxicity and lack of selectivity of conventional chemotherapeutic agents, discovering alternative treatments is a top priority. Plant-derived natural products have high potential in cancer treatment due to their multiple mechanisms of action, diversity in structure, availability in nature, and relatively low toxicity. In this review, the anticancer mechanisms of the most common phytochemicals were analyzed. Furthermore, a detailed discussion of the anticancer effect of combinations consisting of natural product or natural products with chemotherapeutic drugs was provided. This review should provide a strong platform for researchers and clinicians to improve basic and clinical research in the development of alternative anticancer medicines.

Black Seed (Nigella sativa): A Favourable Alternative Therapy for Inflammatory and Immune System Disorders

In the recent years, various food additives, medicinal plants, and their bioactive components have been utilized in anti-inflammatory and immunomodulatory therapy. Nigella sativa is a key dietary supplement and food additive which has a strong traditional background. It is also one of the most broadly studied seeds in the global pharmaceutical and nutraceutical sector. N. sativa seeds are potential sources of natural metabolite such as phenolic compounds and alkaloids. The anti-inflammatory and immunomodulatory abilities of these seeds, most peculiarly with reference to some inflammatory and immune mediators, are reviewed. N. sativa and its bioactive compounds modulate inflammatory and immunomodulatory mediators including tumor necrosis factor-alpha (TNF-α), interferon gamma (IFN-γ), nuclear factor kappa B (NF-kB) cyclooxygenase (COX), lipoxygenase (LOX), transforming growth factor beta (TGF-β), interleukins, and immunoglobulin levels. This paper comprehensively describes the biomarkers and signaling pathways underlying the anti-inflammatory and immunomodulatory potential of N. sativa. This review also explains the scientific basis and the pharmacological properties of core bioactive ingredients of N. sativa responsible for these biological activities which indicates that their bioactive components could be possibly regarded as favorable therapy for disorders linked to inflammation and immune-dysregulation.

Therapeutic implications and clinical manifestations of thymoquinone

Thymoquinone (TQ), a natural phytochemical predominantly found in Nigella sativa, has been investigated for its numerous health benefits. TQ showed anti-cancer, anti-oxidant, and anti-inflammatory properties, validated in various disease models. The anti-cancer potential of TQ is goverened by anti-proliferation, cell cycle arrest, apoptosis induction, ROS production, anti-metastasis and anti-angiogenesis, inhibition of cell migration and invasion action. Additionally, TQ exhibited antitumor activity via the modulation of multiple pathways and molecular targets, including Akt, ERK1/2, STAT3, and NF-κB. The present review highlighted the anticancer potential of TQ . We summarize the anti-cancer, anti-oxidant, and anti-inflammatory properties of TQ, focusing on its molecular targets and its promising action in cancer therapy. We further described the molecular mechanisms by which TQ prevents signaling pathways that mediate cancer progression, invasion, and metastasis.

Discovery of novel natural products as dual MNK/PIM inhibitors for acute myeloid leukemia treatment: Pharmacophore modeling, molecular docking, and molecular dynamics studies

MNK-2 and PIM-2 kinases play an indispensable role in cell proliferation signaling pathways linked to tyrosine kinase inhibitors resistance. In this study, pharmacophore modeling studies have been conducted on the co-crystalized ligands of MNK-2 and PIM-2 enzyme crystal structures to determine the essential features required for the identification of potential dual inhibitors. The obtained pharmacophore features were then screened against a library of 270,540 natural products from the ZINC database. The matched natural molecules were docked into the binding sites of MNK-2 and PIM-2 enzymes. The compounds with high docking scores with the two enzymes were further subjected to MM-GBSA calculations and ADME prediction. This led to the identification of compound 1 (ZINC000085569211), compound 2 (ZINC000085569178), and compound 3 (ZINC000085569190), with better docking scores compared to the reference co-crystallized ligands of MNK-2 and PIM-2. Moreover, compounds 1‒3 displayed better MM-GBSA binding free energies compared to the reference ligands. Finally, molecular dynamics (MD) study was used to assess the interaction stability of the compounds with MNK-2. To this end, compounds 1 and 3 bound strongly to the target during the whole period of MD simulation. The findings of the current study may further help the researchers in the discovery of novel molecules against MNK-2 and PIM-2.

Molecular Signaling Pathway Targeted Therapeutic Potential of Thymoquinone in Alzheimer’s disease

Alzheimer’s disease (AD) is a neurodegenerative disease with rapid progression. Black cumin (Nigella sativa) is a nutraceutical that has been investigated as a prophylactic and therapeutic agent for this disease due to its ability to prevent or retard the progression of neurodegeneration. Thymoquinone (TQ) is the main bioactive compound isolated from the seeds of black cumin. Several reports have shown that it has promising potential in the prevention and treatment of AD due to its significant antioxidative, anti-inflammatory, and antiapoptotic properties along with several other mechanisms that target the altered signaling pathways due to the disease pathogenesis. In addition, it shows anticholinesterase activity and prevents α-synuclein induced synaptic damage. The aim of this review is to summarize the potential aspects and mechanisms by which TQ imparts its action in AD.

Understanding the Prooxidant Action of Plant Polyphenols in the Cellular Microenvironment of Malignant Cells: Role of Copper and Therapeutic Implications

Plant derived polyphenolic compounds are considered critical components of human nutrition and have shown chemotherapeutic effects against a number of malignancies. Several studies have confirmed the ability of polyphenols to induce apoptosis and regression of tumours in animal models. However, the mechanism through which polyphenols modulate their malignant cell selective anticancer effects has not been clearly established. While it is believed that the antioxidant properties of these molecules may contribute to lowering the risk of cancer induction by causing oxidative damage to DNA, it could not be held responsible for chemotherapeutic properties and apoptosis induction. It is a well known fact that cellular copper increases within the malignant cell and in serum of patients harboring malignancies. This phenomenon is independent of the cellular origin of malignancies. Based on our own observations and those of others; over the last 30 years our laboratory has shown that cellular copper reacts with plant derived polyphenolic compounds, by a Fenton like reaction, which generates reactive oxygen species and leads to genomic DNA damage. This damage then causes an apoptosis like cell death of malignant cells, while sparing normal cells. This communication reviews our work in this area and lays the basis for understanding how plant derived polyphenols can behave as prooxidants (and not antioxidants) within the microenvironment of a malignancy (elevated copper levels) and gives rationale for their preferential cytotoxicity towards malignant cells.