Radioprotection by Macerated Extract of Nigella sativa in Normal Tissues of Fibrosarcoma Bearing Mice

Natural Guardians: Natural Compounds as Radioprotectors in Cancer Therapy

Cancer remains a significant global health challenge, with millions of deaths attributed to it annually. Radiotherapy, a cornerstone in cancer treatment, aims to destroy cancer cells while minimizing harm to healthy tissues. However, the harmful effects of irradiation on normal cells present a formidable obstacle. To mitigate these effects, researchers have explored using radioprotectors and mitigators, including natural compounds derived from secondary plant metabolites. This review outlines the diverse classes of natural compounds, elucidating their roles as protectants of healthy cells. Furthermore, the review highlights the potential of these compounds as radioprotective agents capable of enhancing the body's resilience to radiation therapy. By integrating natural radioprotectors into cancer treatment regimens, clinicians may improve therapeutic outcomes while minimizing the adverse effects on healthy tissues. Ongoing research in this area holds promise for developing complementary strategies to optimize radiotherapy efficacy and enhance patient quality of life.

Insights into the antioxidant, anti-inflammatory and anti-microbial potential of Nigella sativa essential oil against oral pathogens

Oral disorders can exert systemic ramifications beyond their localized effects on dental tissues, implicating a wide array of physiological conditions. The utilization of essential oils (EOs) for protection of oral health represents a longstanding practice. Consequently, in this investigation, essential oil derived from Nigella sativa seeds (NSEO) underwent isolation via the hydro-distillation process, followed by a comprehensive evaluation of its antioxidant, anti-inflammatory, anti-fungal, antibacterial activities, and cytocompatibility. The isolated NSEO manifested as a pale-yellow substance and was found to harbor a diverse spectrum of bioactive constituents, including steroids, triterpenoids, flavonoids, phenols, proteins, alkaloids, tannin, sesquiterpenoid hydrocarbons, monoterpenoid alcohol, and monoterpenoid ketone (thymoquinone). Notably, the total phenolic content (TPC) and total flavonoid content (TFC) of NSEO were quantified at 641.23 μg GAE/gm and 442.25 μg QE/g, respectively. Furthermore, NSEO exhibited concentration-dependent inhibition of protein denaturation, HRBC membrane stabilization, and hemolysis inhibition. Comparative analysis revealed that NSEO and chlorhexidine (CHX) 0.2% displayed substantial inhibition of hemolysis compared to aspirin. While NSEO and CHX 0.2% demonstrated analogous antibacterial activity against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa, NSEO showcased heightened efficacy against Lactobacillus acidophilus and Candida albicans. Additionally, NSEO exhibited pronounced effects against periodontal pathogens such as Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, and Prevotella intermedia. Importantly, no cytotoxicity was observed on human gingival fibroblast cell lines. These findings underscore the potential of NSEO as a potent antibacterial and antifungal agent in the management of oral microbial pathogens, thereby offering avenues for the development of innovative therapies targeting diverse oral inflammatory conditions. Nevertheless, further investigations are imperative to unlock its full therapeutic repertoire.

Therapeutic Potential of Thymoquinone in Glioblastoma Treatment: Targeting Major Gliomagenesis Signaling Pathways

Glioblastoma multiforme (GBM) is one of the most devastating brain tumors with median survival of one year and presents unique challenges to therapy because of its aggressive behavior. Current treatment strategy involves surgery, radiotherapy, immunotherapy, and adjuvant chemotherapy even though optimal management requires a multidisciplinary approach and knowledge of potential complications from both the disease and its treatment. Thymoquinone (TQ), the main bioactive component of Nigella sativa L., has exhibited anticancer effects in numerous preclinical studies. Due to its multitargeting nature, TQ interferes in a wide range of tumorigenic processes and counteract carcinogenesis, malignant growth, invasion, migration, and angiogenesis. TQ can specifically sensitize tumor cells towards conventional cancer treatments and minimize therapy-associated toxic effects in normal cells. Its potential to enter brain via nasal pathway due to volatile nature of TQ adds another advantage in overcoming blood-brain barrier. In this review, we summarized the potential role of TQ in different signaling pathways in GBM that have undergone treatment with standard therapeutic modalities or with TQ. Altogether, we suggest further comprehensive evaluation of TQ in preclinical and clinical level to delineate its implied utility as novel therapeutics to combat the challenges for the treatment of GBM.

Anti-cancer properties and mechanisms of action of thymoquinone, the major active ingredient of Nigella sativa

Over the past two decades, studies have documented the wide-range anti-cancer effects of Nigella sativa, known as black seed or black cumin. Thymoquinone (TQ), its major active ingredient, has also been extensively studied and reported to possess potent anti-cancer properties. Herein, we provide a comprehensive review of the findings related to the anti-cancer activity of TQ. The review focuses on analyzing experimental studies performed using different in vitro and in vivo models to identify the anti-proliferative, pro-apoptotic, anti-oxidant, cytotoxic, anti-metastatic, and NK-dependent cytotoxic effects exerted by TQ. In addition, we pinpoint the molecular mechanisms underlying these effects and the signal transduction pathways implicated by TQ. Our analysis show that p53, NF-κB, PPARγ, STAT3, MAPK, and PI3K/AKT signaling pathways are among the most significant pathways through which TQ mediates its anti-cancer activity. Experimental findings and recent advances in the field highlight TQ as an effective therapeutic agent for the suppression of tumor development, growth and metastasis for a wide range of tumors.

Thymoquinone as a Potential Adjuvant Therapy for Cancer Treatment: Evidence from Preclinical Studies

Thymoquinone (TQ), the main bioactive component of Nigella sativa, has been found to exhibit anticancer effects in numerous preclinical studies. Due to its multitargeting nature, TQ interferes in a wide range of tumorigenic processes and counteracts carcinogenesis, malignant growth, invasion, migration, and angiogenesis. Moreover, TQ can specifically sensitize tumor cells toward conventional cancer treatments (e.g., radiotherapy, chemotherapy, and immunotherapy) and simultaneously minimize therapy-associated toxic effects in normal cells. In this review, we summarized the adjuvant potential of TQ as observed in various in vitro and in vivo animal models and discussed the pharmacological properties of TQ to rationalize its supplementary role in potentiating the efficacy of standard therapeutic modalities namely surgery, radiotherapy, chemotherapy, and immunotherapy. Altogether, we suggest further comprehensive evaluation of TQ in preclinical and clinical levels to delineate its implied utility as a novel complementary adjuvant therapy for cancer treatment.

Recent advances on the anti-cancer properties of Nigella sativa, a widely used food additive

The use of naturally-occurring agents to regulate tumorigenesis is on the rise. Several herbal extracts, pure plant-derived active constituents, and food additives have been reported to possess potent anti-cancer properties and cancer-ameliorating effects. The wide-range anti-cancer effects of Nigella sativa, also known as black seed or black cumin, have been extensively studied using different in vitro and in vivo models. Here, we provide a comprehensive, analytical review of the reported anti-cancer properties of N. sativa seed extracts. This review focuses on analyzing experimental findings related to the ability of N. sativa to exert anti-proliferative, pro-apoptotic, anti-oxidant, cytotoxic, anti-mutagenic, anti-metastatic, and NK cytotoxic activity enhancing effects against various primary cancer cells and cancer cell lines. Moreover, we underline the molecular mechanisms of action and the signal transduction pathways implicated in the suppression of tumorigenesis by N. sativa. The major signaling pathway utilized by N. sativa to manifest its anti-cancer activity is the iNOS signaling pathway. This review underscores the recent developments that highlight an effective therapeutic potential of N. sativa to suppress tumor development, reduce tumor incidence, and ameliorate carcinogenesis. In sum, experimental findings reported in the last two decades strongly suggest that N. sativa fractions could serve, alone or in combination with known chemotherapeutic drugs, as effective agents to control tumor initiation, growth, and metastasis, and hence, treatment of a wide range of cancers.

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N. sativa exerts cytotoxic, pro-apoptotic, anti-proliferative, anti-oxidant, anti-mutagenic, and anti-metastatic effects.

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Augmentation of NK cytotoxic activity is a one molecular mechanism by which N. sativa manifests its anti-cancer activity.

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The anti-cancer effects of N. sativa are primarily mediated via iNOS, p53, and caspase signaling pathways.

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N. sativa extracts can potentially be employed in the development of effective anti-cancer therapeutic agents.

Immunomodulatory and anti-inflammatory action of Nigella sativa and thymoquinone: A comprehensive review

Many herbal products are now used as remedies to treat various infectious and non-infectious conditions. Even though the use of herbs and natural products is much more evident in the Eastern world, their use in Western cultures is continuously increasing. Although the immunomodulatory effects of some herbs have been extensively studied, research related to possible immunomodulatory effects of many herbs and various spices is relatively scarce. Here, we provide a comprehensive review of the immunomodulatory and anti-inflammatory properties of Nigella sativa, also known as black seed or black cumin, and its major active ingredient, thymoquinone (TQ). This review article focuses on analyzing in vitro and in vivo experimental findings that were reported with regard to the ability of N. sativa and TQ to modulate inflammation, cellular and humoral adaptive immune responses, and Th1/Th2 paradigm. The reported capability of N. sativa to augment the cytotoxic activity of natural killer (NK) cells against cancer cells is also emphasized. The molecular and cellular mechanisms underlying such immunomodulatory and anti-inflammatory effects of N. sativa and TQ are highlighted. Moreover, the signal transduction pathways implicated in the immunoregulatory functions of N. sativa and TQ are underscored. Experimental evidence suggests that N. sativa extracts and TQ can potentially be employed in the development of effective therapeutic agents towards the regulation of immune reactions implicated in various infectious and non-infectious conditions including different types of allergy, autoimmunity, and cancer.