Immunomodulatory and therapeutic properties of the Nigella sativa L. seed

Is Nigella sativa an Effective Bodyweight Lowering Agent and a Mitigator of Obesity Risk? A Literature Review

Obesity is one of the major health-threatening conditions nowadays. Nigella sativa (NS) is a medicinal plant that demonstrates multiple therapeutic effects. In the current review, we aim to evaluate the weight lowering effect of NS in both clinical trials and experimental studies and to explore the possible reported mechanisms of this effect. We searched PubMed and Web of science and retrieved 14 clinical trials and 5 experimental studies that justify our inclusion criteria. After the analysis of these articles, we can conclude that long-term administration of NS for 6–12 weeks can significantly lower bodyweight and other anthropometric indices. NS-oil is more potent than NS-powder in lowering bodyweight probably due to the higher concentration of fatty acids and thymoquinone. The weight lowering effect of NS is not a toxic effect, it conversely and preferably lowers the elevated liver enzymes in condition of fatty liver. It is also frequently accompanied by positive metabolic modifications, such as enhancement of lipid profile, lowering blood glucose and improving insulin resistance. Possible mechanisms for NS-bodyweight lowering effect might include an appetite-suppression effect, lowering caloric-intake and inhibition of intestinal glucose absorption. However, further experimental evidence is required to support these mechanisms or unveil new ones.

An Overview of the Neuropharmacological Potential of Thymoquinone and its Targeted Delivery Prospects for CNS Disorder

At present, people and patients worldwide are relying on the medicinal plant as a therapeutic agent over pharmaceuticals because the medicinal plant is considered safer, especially for chronic disorders. Several medicinal plants and their components are being researched and explored for their possible therapeutic contribution to CNS disorders. Thymoquinone (TQ) is one such molecule. Thymoquinone, one of the constituents of Plant Nigella Sativa, is effective against several neurodegenerative diseases like; Alzheimer's, Depression, Encephalomyelitis, Epilepsy, Ischemia, Parkinson's, and Traumatic. This review article presents the neuropharmacological potential of TQ's, their challenges, and delivery prospects, explicitly focusing on neurological disorders along with their chemistry, pharmacokinetics, and toxicity. Since TQ has some pharmacokinetic challenges, scientists have focused on novel formulations and delivery systems to enhance bioavailability and ultimately increase its therapeutic value. In the present work, the role of nanotechnology in neurodegenerative disease and how it improves bioavailability and delivery of a drug to the site of action has been discussed. There are a few limitations for developing novel drug formulation, including solubility, pH, and compatibility of nanomaterials. Since here we are targeting CNS disorders, the blood-brain barrier (BBB) becomes an additional challenge Hence, the review summarized the novel aspects of delivery and biocompatible nanoparticles-based approaches for targeted drug delivery into CNS, enhancing TQ bioavailability and its neurotherapeutic effects.

Black Seed Oil, Bentonite Clay, and Probiotics: A Comprehensive Holistic Cure for Clostridium difficile Infection in a 2-Year-Old Female Child

There has been a rise in antibiotic resistance in secondary conditions such as Clostridium difficile (C. difficile) due to overuse of antibiotics. Oral antibiotics are used to treat C. difficile, which further disrupts the intestinal flora resulting in unwanted side effects. Naturopathic treatments often have fewer side effects and lower secondary infection risk than pharmaceutical interventions making them ideal for pediatric use. This case report describes the effective treatment of a pediatric clinical case of C. difficile using naturopathic and complementary alternative medicines (CAMs) including black seed oil (Nigella sativa), bentonite clay, and probiotics. A healthy two-year-old patient presented to a pediatrician with symptoms of, and subsequently confirmed, C. difficile after having been recently hospitalized and treated for a gluteal abscess and cellulitis using clindamycin, vancomycin, and piperacillin/tazobactam. Through a shared decision-making process, the patient's mother and providers developed a treatment plan for the C. difficile infection (CDI), which included black seed oil, bentonite clay, and Lactobacillus probiotics. No C. difficile was detected via stool immunoassay after 4 days of combined CAM therapy. Our results underscore the need for additional research regarding the effectiveness of naturopathic CAMs including black seed oil, bentonite clay, and probiotics as alternatives to antibiotic treatment of CDI in children.

Nigella sativaoil extract: A natural novel specific conjugal transfer inhibitor of vancomycin resistance from vanA/B Resistant Enterococcus faecium to Staphylococcus aureus

AIM

The emergence of vancomycin-resistant Staphylococcus aureus (VRSA) has been identified as one of the most challenging problems in healthcare settings worldwide. Specific conjugation inhibitors development are critical in the fight against the spread of emerging VRSA. The impact of Nigella sativa oil on VR genes conjugal transfer from Enterococcus faecium (VREtfm) to vancomycin sensitive S. aureus (VSSA) was investigated in this study.

METHODS AND RESULTS

Enterococci were isolated from retail broilers, fish, cows' milk, and human urine. VR Enterococcus faecalis and VREtfm VanA-phenotype' were prevalent in retail broiler samples. The VREtfm isolates were dominant, exhibiting high levels of resistance to gentamycin and ciprofloxacin antibiotics, as well as the existence of both vanA and vanB genes and virulence traits (ESP+, asa1+) as determined by PCR. VREtfm strains containing vanA/vanB genes and transconjugants containing 20Kb plasmids (transfer frequency around 10³ ) and carrying the Tn1546 transposon were identified. Tn1546 transposon transfer with its VR markers to VSSA was effectively inhibited in treated VREtfm donor strains with a sub-MIC of N. sativa oil.

THE SIGNIFICANCE AND IMPACT OF THE STUDY

This work offers new insights for overcoming VR conjugal transfer utilising natural N. sativa oil, as well as a suggestion for a novel specialized conjugation inhibitor that could effectively facilitate the difficulty of eliminating VR bacteria from healthcare settings.

Thymoquinone: A Review of Pharmacological Importance, Oxidative Stress, COVID-19, and Radiotherapy

Widely consumed worldwide, Nigella sativa (NS) is a medicinal herb commonly used in various alternative medicine systems such as Unani and Tibb, Ayurveda, and Siddha. Recommended for regular use in Tibb-e-Nabwi (Prophetic Medicine), NS is considered one of the most notable forms of healing medicine in Islamic literature. Thymoquinone (TQ), the main component of the essential oil of NS, has been reported to have many properties such as antioxidant, anti-inflammatory, antiviral, and antineoplastic. Its chemical structure indicates antiviral potential against many viruses, including the hepatitis C virus, human immunodeficiency virus, and other coronavirus diseases. Interestingly, molecular docking studies have demonstrated that TQ can potentially inhibit the development of the coronavirus disease 2019 (COVID-19) by binding to the receptor site on the transmembrane serine proteinase 2 (the activator enzyme that attaches the virus to the cell). In addition, TQ has been shown to be effective against cancer cells due to its inhibitory effect by binding to the different regions of MDM2, according to the proposed molecular docking study. Detailed in this review is the origin of TQ, its significance in alternative medicine, pharmacological value, potential as a cancer anti-proliferative agent, use against the coronavirus disease 2019 (COVID-19), and treatment of other diseases.

From Molecular Pathology of COVID 19 to Nigella Sativum as a Treatment Option: Scientific Based Evidence of Its Myth or Reality

COVID-19 virus is a causative agent of viral pandemic in human beings which specifically targets respiratory system of humans and causes viral pneumonia. This unusual viral pneumonia is rapidly spreading to all parts of the world, currently affecting about 105 million people with 2.3 million deaths. Current review described history, genomic characteristics, replication, and pathogenesis of COVID-19 with special emphasis on Nigella sativum (N. sativum) as a treatment option. N. sativum seeds are historically and religiously used over the centuries, both for prevention and treatment of different diseases. This review summarizes the potential role of N. sativum seeds against COVID-19 infection at levels of in silico, cell lines and animal models.

Preparation of Liposomal Formulations for Ocular Delivery of Thymoquinone: In Vitro Evaluation in HCEC-2 e HConEC Cells

Thymoquinone (TQ) is the main constituent of Nigella sativa L. essential oil. In vitro studies have shown its protective effect against H₂O₂-induced oxidative stress in human retinal pigment epithelium cells, and in vivo experiments have demonstrated its effect in decreasing corneal neovascularization and reducing the inflammation in an experimental dry eye model in mice. Its therapeutic use is limited by poor bioavailability, low solubility, and scarce permeability. In this study, two liposomal formulations have been developed, both of which consist of phosphatidylcholine and Plurol Oleique, a liquid lipid, and one of which is coated with 0.1% w/v hyaluronic acid (HA) to increase both TQ solubility and its ocular therapeutic potential. Each formulation has a size <200 nm and an EE% around 70%, determined by scattering techniques and the HPLC-DAD analytical method, respectively, and they result in a 2-fold increase in TQ solubility. HA-coated liposomes are stable over 2 months at +4 °C, and coated and uncoated liposomes present a gradual and prolonged release of TQ. Two cell lines, human corneal epithelial cells (HCEC-2) and human conjunctival epithelial cells (HConEC) were used to investigate the safety of the liposomal formulations. Uptake studies were also performed using fluorescent liposomes. Both liposomes and, in particular, HA-coated liposomes reduce the TQ toxicity observed at high doses in both HCEC-2 and HConEC cells, and both formulations increase the absorption at the cellular level and especially at the nucleus level, with a more pronounced effect for HA-coated liposomes.

Chronic Administration of Thymoquinone Enhances Adult Hippocampal Neurogenesis and Improves Memory in Rats Via Regulating the BDNF Signaling Pathway

Thymoquinone is a pharmacologically active component of Nigella sativa Linn. seeds. Despite the diverse neuropharmacological attributes of TQ, limited reports related to adult neurogenesis and memory research are available. In this study, we investigated the effects of TQ on the proliferation and neural differentiation of cultured neural stem/progenitor cells (NSCs/NPCs). We also investigated the effect of TQ chronic administration on neurogenesis and memory in adult rats. Under proliferation conditions, TQ (0.05-0.3 μM) significantly increased NSCs/NPCs viability, neurosphere diameter, and cell count. TQ treatment under differentiation conditions increased the proportion of cells positive for Tuj1 (a neuronal marker). Furthermore, chronic oral administration of TQ (25 mg/kg/day for 12 weeks) to adult rats increased the number of bromodeoxyuridine (BrdU)-immunopositive cells double-stained with a mature neuronal marker, neuronal nuclei (NeuN), and a proliferation marker, doublecortin (Dcx), in the dentate gyrus of the hippocampus. TQ-administered rats showed a profound beneficial effect on avoidance-related learning ability, associated with an increase in the hippocampal mRNA and protein levels of brain-derived neurotrophic factor (BDNF), as measured by both real-time PCR and ELISA. Western blot analysis revealed that TQ stimulates the phosphorylation of cAMP-response element-binding protein (CREB), the upstream signaling molecule in the BDNF pathway. Furthermore, chronic administration of TQ decreased lipid peroxide and reactive oxygen species levels in the hippocampus. Taken together, our results suggest that TQ plays a role in memory improvement in adult rats and that the CREB/BDNF signaling pathways are involved in mediating the actions of TQ in hippocampal neurogenesis.

Possible therapeutic effects of Nigella sativa and its thymoquinone on COVID-19

CONTEXT

COVID-19 is a novel coronavirus that causes a severe infection in the respiratory system. Nigella sativa L. (Ranunculaceae) is an annual flowering plant used traditionally as a natural food supplement and multipurpose medicinal agent.

OBJECTIVE

The possible beneficial effects of N. sativa, and its constituent, thymoquinone (TQ) on COVID-19 were reviewed.

METHODS

The key words including, COVID-19, N. sativa, thymoquinone, antiviral effects, anti-inflammatory and immunomodulatory effects in different databases such as Web of Science (ISI), PubMed, Scopus, and Google Scholar were searched from 1990 up to February 2021.

RESULTS

The current literature review showed that N. sativa and TQ reduced the level of pro-inflammatory mediators including, IL-2, IL-4, IL-6, and IL-12, while enhancing IFN-γ. Nigella sativa and TQ increased the serum levels of IgG1 and IgG2a, and improved pulmonary function tests in restrictive respiratory disorders.

DISCUSSION AND CONCLUSIONS

These preliminary data of molecular docking, animal, and clinical studies propose N. sativa and TQ might have beneficial effects on the treatment or control of COVID-19 due to antiviral, anti-inflammatory and immunomodulatory properties as well as bronchodilatory effects. The efficacy of N. sativa and TQ on infected patients with COVID-19 in randomize clinical trials will be suggested.

Assessment of black cumin (Nigella sativa L.) as a food ingredient and putative therapeutic agent

The whole or ground seeds of the food ingredient Nigella sativa L., known in Western culture as "black cumin" or "black caraway", has a three-millennial history of use in Middle- and Far-Eastern cultures as a food ingredient. The seed and its extracts have also been increasingly reported as a successful therapeutic agent with efficacy often attributed to the presence of the powerful antioxidant, thymoquinone. However, quantitative analysis of the seed (especially the volatile fraction) yields widely variable results, which may be due to one or a combination of different crop origins or possible varietal differences, contamination/adulteration, method of extraction, stage of maturation of the extracted seed and other factors. Nonetheless, despite the reported wide variability in bioactive constituents, many publications cite quantifiable outcomes in in vitro and in vivo toxicity testing and in clinical trials. There are a few reports describing allergic reactions in humans when N. sativa extracts are applied to the skin. Notwithstanding the foregoing, N. sativa seeds, used as a food ingredient at historical levels of consumption and as traditionally practiced are safe and Generally Recognized As Safe.

Effect of Nigella sativa on general health and immune system in young healthy volunteers; a randomized, placebo-controlled, double-blinded clinical trial

Nigella sativa (N. sativa) is traditionally used as an immune enhancer in different communities. The aim of this study was to evaluate the effect of N. sativa on immunity related parameters in young healthy subjects. This study was a double blind, randomized, placebo controlled clinical trial. Fifty-two healthy subjects (48 male and 4 female) 18-25 years old were enrolled in the study. They were randomly divided into four groups; the first received charcoal capsules and served as controls and the other three received 0.5, 1 g, and 2 g of powdered N. sativa capsules, respectively. Two blood samples were obtained from all participant, before initiation of the trial and at the end of the four weeks intervention. One sample was used for routine health screening by evaluating liver and renal functions as well as complete blood count and differential. The second sample was used to measure certain cytokines including; IL-1, IL-4, IL-6, IL-10, and TNF. A third and fourth samples were obtained from the last cohort of subjects before and after treatment; the third was used for measuring immunoglobulins and CD profile and the fourth for evaluating certain gene expressions (INF-γ, NF-κ-B, TNF-α, IL-1β, IL-13, IL-8, and IL-6). Only 1 g dose of N. sativa produced a significant elevation in total lymphocyte count, CD3+ and CD4+ counts. One gram N. sativa increased the absolute lymphocyte count from 1850±0.24 to 2170±0.26 (p=0.008), CD3+ from 1184.4±75.60 to 1424±114.51 (p=0.009), and CD4+ from 665.6±141.66 to 841±143.36 (p=0.002).  This elevation in T cells was lost by increasing the dose of N. sativa to 2g. The rest of the parameters were not changed significantly in all doses. The results show a promising immunopotentiation effect of N. sativa by elevating helper T cells and the optimum dose for young age group seems to be 1 g.

Functionality of Films from Nigella sativa Defatted Seed Cake Proteins Plasticized with Grape Juice: Use in Wrapping Sweet Cherries

The main aim of this work is to improve the functionality of Nigella sativa protein concentrate (NSPC) films by using grape juice (GJ). The film’s mechanical, antioxidant, and antimicrobial activities were evaluated. The obtained results showed, for the first time, that GJ at concentrations of 2%–10% (v/v) are able to act as plasticizer for the NSPC films with promising film properties. The results showed that the tensile strength and Young’s modulus of NSPC films were reduced significantly when the GJ increased. However, the NSPC films prepared with 6% GJ observed a higher elongation at break compared with other films. Moreover, the obtained films showed very interesting and promising results for their antioxidant and antimicrobial properties compared with the control films. The sweet cherries wrapped with NSPC film showed that the TSS (Brix) was significantly lower compared to the control, after 10 days of storage. However, the titratable acidity, pH value, and L* of all cherries, either wrapped or not, was not significantly different in all storage times. On the other hand, hue angle was significantly lower after 10 days of storage at −18 °C compared with control films. GJ has a multi-functional effect for protein-based films as plasticizer, antioxidant, and antimicrobial function.

Honey in wound healing: An updated review

Wound healing is a complex process with many interdependent pathophysiological and immunological mediators to restore the cellular integrity of damaged tissue. Cutaneous wound healing is the repair response to a multitude of pathologies induced by trauma, surgery, and burn leading to the restoration and functionality of the compromised cells. Many different methods have been employed to treat acute and chronic wounds, such as antimicrobial therapy, as most wounds are susceptible to infection from microbes and are difficult to treat. However, many antimicrobial agents have become ineffective in wound treatment due to the emergence of multiple drug-resistant bacteria, and failures in current wound treatment methods have been widely reported. For this reason, alternative therapies have been sought, one of which is the use of honey as a wound treatment agent. The use of honey has recently gained clinical popularity for possible use in wound treatment and regenerative medicine. With this high demand, a better delivery and application procedure is required, as well as research aiming at its bioactivity. Honey is a safe natural substance, effective in the inhibition of bacterial growth and the treatment of a broad range of wound types, including burns, scratches, diabetic boils (Skin abscesses associated with diabetic), malignancies, leprosy, fistulas, leg ulcers, traumatic boils, cervical and varicose ulcers, amputation, burst abdominal wounds, septic and surgical wounds, cracked nipples, and wounds in the abdominal wall. Honey comprises a wide variety of active compounds, including flavonoids, phenolic acid, organic acids, enzymes, and vitamins, that may act to improve the wound healing process. Tissue-engineered scaffolds have recently attracted a great deal of attention, and various scaffold fabrication techniques are being researched. Some incorporate honey to improve their delivery during wound treatment. Hence, the aim of this review is to summarize recent studies on the wound healing properties of honey.

Influence of Supercritical Carbon Dioxide Extraction Conditions on Extraction Yield and Composition of Nigella sativa L. Seed Oil-Modelling, Optimization and Extraction Kinetics regarding Fatty Acid and Thymoquinone Content

Nigella sativa L. is cultivated in many regions and its seeds have found use in variety of foods, but also in traditional medicine due to high content of biologically active essential oils. In this work optimization of supercritical carbon dioxide extraction from N. sativa seeds was performed using response surface methodology to describe the influence of extraction conditions on oil yield. Kinetics of oil and thymoquinone extraction were analyzed as well. It was demonstrated that in order to collect thymoquinone-rich N. sativa oil fraction, appropriate for health-related applications, the extraction should be carried out at 40 °C and 10-15 MPa. Following application of higher pressure of 35 MPa enables effective extraction of remaining oil rich in polyunsaturated fatty acids suitable for use in food industry. Thymoquinone-dependent antibacterial activity of the N. sativa seed oil was observed against bacterial pathogens: Haemophilus influenzae, Staphylococcus haemolyticus, Staphylococcus epidermidis, Enterococcus faecalis and Escherichia coli.

Potential role of herbal medicines as a novel approach in sepsis treatment

The growing number of deaths related to sepsis has become a major concern for past few years. Sepsis is a complex pathological reactions that is explained by series of host response to microbial insult. The resulted systemic reactions are manifested by early appearance of proinflammatory cytokines leading to hyperinflammatory phase which is followed by septic shock and death of the patient. The present study has revealed that antibiotics are not self-sufficient to control the complex mechanism of sepsis. Moreover prolonged and unnecessary administration of antibiotics may lead to antibiotic resistance to pathogens. In addition to this, immunosuppressive medications are selective and have targeted approach to certain study population. Drugs from herbal origin have shown to possess a mammoth of immunomodulatory potential by suppressing proinflammatory and anti-inflammatory cytokines exhibiting no or minimal unwanted secondary responses. Concomitantly, herbal plants tend to modulate oxidative stress level and haematological imbalance during inflammatory diseased conditions. Natural compounds have gained much attention for the treatment of several clinical complications. Considering the promising responses of medicinal plants with less/no side effects and easy procurement, comprehensive research on herbal plants to treat sepsis should be contemplated.

The efficacy of Nigella sativa supplementation for asthma control: a meta-analysis of randomized controlled studies

Introduction

The efficacy of Nigella sativa supplementation for asthma control remains controversial. We have conducted a systematic review and meta-analysis to explore the influence of Nigella sativa supplementation on asthma control.

Material and methods

We have searched PubMed, EMBASE, Web of science, EBSCO, and Cochrane library databases through June 2019 for randomized controlled trials (RCTs) assessing the efficacy of Nigella sativa supplementation for asthma control.

Results

Four RCTs are included in the meta-analysis. Overall, compared with the control group for asthma, Nigella sativa supplementation is associated with the increased ACT scores (SMD = 0.50; 95% CI: 0.11–0.88; p = 0.01), and FEV1 (SMD = 1.84; 95% CI: 0.07–3.60; p = 0.04), but demonstrates no obvious impact on PEF (SMD = 3.11; 95% CI: –1.30 to 7.52; p = 0.17), IL-4 (SMD = –0.31; 95% CI: –1.21 to 0.59; p = 0.50), or IFN-γ (SMD = 1.11; 95% CI: –0.44 to 2.67; p = 0.16).

Conclusions

Nigella sativa supplementation may provide additional benefits for the treatment of asthma.

Anti-Inflammatory Activity of S. Marianum and N. Sativa Extracts on Macrophages

Background

Nigella sativa (N. sativa) and Silybum marianum (S. marianum) are used to regulate macrophage polarization in lipopolysaccharide-induced RAW 264.7 cells and thioglycollate-elicited peritoneal inflammation.

Methods

Cytotoxicity assays and acute toxicity tests were performed to investigate the safe dose and toxicity of the prepared extracts. Also, nitric oxide production was determined by Griess assay on RAW264.7 and peritoneal macrophage supernatants. After RNA extraction from macrophages, real-time PCR was performed to measure the relative gene expression of tumor necrosis factor (TNF)-α, interleukin (IL)-6, transforming growth factor (TGF)-β, and IL-10. Finally, regulatory T cells (Treg cells) were counted by flow cytometry.

Results

S. marianum methanolic extract (SME), N. sativa ethanolic extract (NEE), and their mixture (SME+NEE) decreased NO levels significantly in RAW264.7 and peritoneal murine macrophages. N. sativa ethanolic extract significantly increased IL-10 gene expression and significantly decreased IL-6 and TNF-α expression in RAW264.7 cells. In mixture-treated peritoneal macrophages, IL-10 and TGF-β expression were significantly increased, while IL-6 and TNF-α were significantly decreased. Also, the percentage of Treg cells was significantly greater in the mixture-treated cells than in controls.

Conclusion

These results suggest that an SME and NEE mixture has anti-inflammatory and immunomodulatory activities and may be useful in the treatment of diseases of immunopathologic origin characterized by macrophage hyperactivation.

Development and optimization of sitagliptin and dapagliflozin loaded oral self-nanoemulsifying formulation against type 2 diabetes mellitus

Control of hyperglycemia and prevention of glucose reabsorption (glucotoxicity) are important objectives in the management of type 2 diabetes. This study deals with an oral combined dosage form design for two anti-diabetic drugs, sitagliptin and dapagliflozin using self-nanoemulsifying drug delivery systems (SNEDDS). The SNEDDS were developed using naturally obtained bioactive medium-chain/long-chain triglycerides oil, mixed glycerides and nonionic surfactants, and droplet size was measured followed by the test for antioxidant activities. Equilibrium solubility and dynamic dispersion experiments were conducted to achieve the maximum drug loading. The in vitro digestion, in vivo bioavailability, and anti-diabetic effects were studied to compare the representative SNEDDS with marketed product Dapazin^®. The representative SNEDDS containing black seed oil showed excellent self-emulsification performance with transparent appearance. Characterization of the SNEDDS showed nanodroplets of around 50–66.57 nm in size (confirmed by TEM analysis), in addition to the high drug loading capacity without causing any precipitation in the gastro-intestinal tract. The SNEDDS provided higher antioxidant activity compared to the pure drugs. The in vivo pharmacokinetic parameters of SNEDDS showed significant increase in C_max (1.99 ± 0.21 µg mL⁻¹), AUC (17.94 ± 1.25 µg mL⁻¹), and oral absorption (2-fold) of dapagliflozin compared to the commercial product in the rat model. The anti-diabetic studies showed the significant inhibition of glucose level in treated diabetic mice by SNEDDS combined dose compared to the single drug therapy. The combined dose of sitagliptin-dapagliflozin using SNEDDS could be a potential oral pharmaceutical product for the improved treatment of type 2 diabetes mellitus.

Nigella sativa extract kills pre-malignant and malignant oral squamous cell carcinoma cells

In this study, the potential of Nigella sativa was evaluated in the management of oral cancer through assays designed to mimic conditions expected when chewing the whole seeds or use of a seed extract. For this purpose, a water-based extract of N. sativa seeds was prepared, mimicking the chewing process. This extract demonstrated significant cytotoxic effect on oral cancer and pre-cancerous leukoplakia cells in vitro at a much lower concentration than the predicted oral concentration that could be achieved upon seed chewing. When the active constituent(s) in this water-based N. sativa seed extract, was explored significant quantities of the compound α-hederin was detected but only modest quantities of thymoquinone suggesting that thymoquinone is not fully released into the aqueous medium during the chewing process. While the N. sativa seed extract induced a different effect on the cells than that of pure thymoquinone, α-hederin alone induced a very similar effect on the cells to that of the extract. These results suggest that α-hederin and not thymoquinone, is the major component of the seed that is responsible for the inhibitory effect observed in vitro. Therefore, chewing N. sativa whole seeds or applying a concentrated extract on the oral lesions may be an inexpensive, widely available, and effective option for patients at risk of developing oral cancer who are receiving no other preventive treatment.

Amelioration of polycystic ovary syndrome-related disorders by supplementation of thymoquinone and metformin

Background

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders of reproductive age women with a prevalence of 4-12%. The study aimed to investigate the potential benefit of adding thymoquinone to metformin in alleviating symptoms of polycystic ovarian syndrome. Two hundred seven overweight and obese PCOS patients were divided into two groups. Patients in group A received metformin 500 mg three times daily for 6 months. Patients in group B received a combination of metformin 500 mg and thymoquinone in the form of black cumin oil 500 mg capsules three times daily for 6 months. Follow-up was done after 3 and 6 months from the beginning of the study for evaluation of menstrual cycle pattern, body mass index, waist circumference, hip circumference, and waist:hip ratio, oral glucose tolerance test, glycosylated hemoglobin A1C, superoxide dismutase activity, and malondialdehyde concentration.

Results

Patients who received a combination of black cumin oil capsules and metformin, showed a significant decrease in number of patients suffering from amenorrhea or oligomenorrhea (P = 0.031), significant (P = 0.00) weight reduction (reduced BMI), and body fat redistribution (reduced W/H ratio), regaining oxidative balance with significant increase of SOD activity (P = 0.00) and decrease of MDA concentrations (P = 0.03). Regarding the number of prediabetic patients, there was no statistically significant difference (P = 0.89) when both groups were compared at the end of study period.

Conclusions

Black cumin oil supplementation constitutes a beneficial added value to metformin in ameliorating PCOS-related disorders with resumption of menstrual regularity, weight reduction, change of body fat distribution, and regaining oxidative balance.

Oral Nigella sativa oil administration alleviates arsenic-induced redox imbalance, DNA damage, and metabolic and histological alterations in rat liver

Arsenic, an omnipresent environmental contaminant, is regarded as a potent hepatotoxin. Nigella sativa oil (NSO) consumption has been shown to improve hepatic functions in various in vivo models of acute hepatic injury. The present study evaluates the protective efficacy of NSO against sodium arsenate (As)-induced deleterious alterations in the liver. Male Wistar rats were divided into four groups, namely, control, As, NSO, and AsNSO. After pre-treating rats in AsNSO and NSO groups with NSO (2 mL/kg bwt, orally) for 14 days, NSO treatment was further extended for 30 days, with and without As treatment (5 mg/kg bwt, orally), respectively. As induced an upsurge in serum ALT and AST activities indicating liver injury, as also confirmed by the histopathological findings. As caused significant alterations in the activities of membrane marker enzymes and carbohydrate metabolic enzymes, and in the vital components of antioxidant defense system. Marked DNA damage and hepatic arsenic accumulation were also observed in As-treated rats. Oral NSO administration ameliorated these deleterious alterations and improved overall hepatic antioxidant and metabolic status in As-treated rats. Prevention of oxidative damage could be the underlying mechanism of NSO-mediated protective effects. The results suggest that NSO could be a useful dietary supplement in the management of arsenic hepatotoxicity.

A qualitative and quantitative comparison of Crocus sativus and Nigella sativa immunomodulatory effects

The present article reviews and compares the immunomodulatory activities of Crocus sativus (C. sativus) and Nigella sativa (N. sativa) and their main bioactive compounds. Immunomodulatory effects of these plants, especially with respect to Th1 and Th2 cytokines, are discussed based on relevant articles, books, and conference papers published in English until the end of April 2020, that were retrieved from Web of Science, PubMed, Scopus and Google Scholar databases. C. sativus and its constituents increase immunoglobulin (Ig-)G, interleukin 2 (IL)-2, interferon gamma (IFN-γ), and IFN-γ/IL-4 ratio, but decreased IgM, IL-10 and IL-4 secretion. N. sativa extract and thymoquinone reduce the levels of IL-2, -4, -10, and -12, while enhance IFN-γ and serum IgG1 and 2a. The reviewed articles indicate that C. sativus and N. sativa and their constituents could be potentially considered promising treatments for disorders associated with immune-dysregulation such as asthma and cancer.

The potential role of thymoquinone in preventing the cardiovascular complications of COVID-19

A new virus strain detected in late 2019 and not previously described in humans is the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes corona virus disease (COVID-19). While potential therapeutic approaches for COVID-19 are being investigated, significant initiatives are being made to create protective drugs and study various antiviral agents to cure the infection. However, an effective treatment strategy against COVID-19 is worrisome inadequate. The objective of the present manuscript is to discuss the potential role of thymoquinone (TQ) in preventing the cardiovascular complications of COVID-19, focusing on viral inhibition, antioxidant potential, vascular effect, and cardiac protection. The multifunctional properties of TQ could potentially synergize with the activity of current therapeutic interventions and offer a basis for managing COVID-19 disease more effectively. Even though the experimental evidence is positive, a translational application of TQ in COVID-19 is timely warranted.

Effects of Nigella sativa on Performance, Blood Profiles, and Antibody Titer against Newcastle Disease in Broilers

Recent anxiety about resistance to chemical drugs has elevated the position of phytogenic feed additives including Nigella sativa in preventive strategy in the poultry industry. During this study, a completely randomized experiment was designed to investigate the efficacy of different levels (0 to 16%) of N. sativa seeds supplemented in the diet of broilers on performance, immune responses, and hematological and biochemical parameters. The results indicated the following: (a) Supplementation of 1% N. sativa seeds in diet had the highest positive effects and 16% N. sativa had the highest significant (p=0.03) adverse effects on weight gain, while up to 2% N. sativa seeds in the diet reduced feed conversion ratio (FCR) whereas 4% and over that increased the FCR. (b) Chickens fed with a diet containing 1% N. sativa seeds had the highest antibody titers, but those fed with 16% N. sativa seeds had the lowest antibody titers at end of the experiment. (c) Dietary inclusion of N. sativa seeds increased hemogram parameters and the group fed with 16% N. sativa seeds had the highest values on day 21 until the end of the experiment. (d) Supplementation of N. sativa seeds decreased in WBC and lymphocytes but increased heterophils, H/L, monocytes, eosinophils, and basophils percentages. Supplementation of up to 2% of N. sativa seeds in broiler's diets elaborated serum level of those parameters, while supplementation of ≥ 4% N. sativa seeds decreased their serum levels. In conclusion, supplementation of N. sativa seed (1-2%) in broiler diets, as a multipurpose natural growth promoter, improves performance, elevates humoral immune responses, affects serum biochemical profiles of broiler chickens, and induces changes in their hemogram and leukogram, while there are no side, residual, and hazardous effects.

Therapeutic perspectives of the black cumin component thymoquinone: A review

The dietary phytochemical thymoquinone (TQ), belonging to the family of quinones, mainly obtained from the black and angular seeds of Nigella sativa, is one of the promising monoterpenoid hydrocarbons, which has been receiving massive attention for its therapeutic potential and pharmacological properties. It plays an important role as a chemopreventive and therapeutic agent in the treatment of various diseases and illnesses. The aim of this review is to present a summary of the most recent literature pertaining to the use of TQ for the prevention and treatment of various diseases along with possible mechanisms of action, and the potential use of this natural product as a complementary or alternative medicine. Research findings indicated that TQ exhibits numerous pharmacological activities including antioxidant, anti-inflammatory, cardioprotective, hepatoprotective, antidiabetic, neuroprotective, and anticancer, among others. Conclusions of this review on the therapeutic aspects of TQ highlight the medicinal and folk values of this compound against various diseases and ailments. In short, TQ could be a novel drug in clinical trials, as we hope.

The positive effect of black seed (Nigella sativa L.) essential oil on thyroid hormones in rats with hypothyroidism and hyperthyroidism

In our study, the effect of essential oil obtained from Nigella sativa L. (NSE) on thyroid hormones and antioxidant balance in hypothyroidism (HT) and hyperthyroidism (HP) models induced by propylthiouracil(PTU) and L-thyroxine(LT₄ ), respectively, in rats were investigated for 4 weeks. NSE was administered by gastric gavage at a dose of 200 mg/kg body weight. In this study, 48 male Wistar albino rats with an average weight of 180-290 g and age 5-6 months were divided into eight groups, as follows: groups with HT, (1) control, (2) HT, (3) NSE, and (4) HT + NSE; groups with HP, (1) control, (2) HP, (3), and NSE (4) HP + NSE. As a result, we found that NSE administration increased total triiodothyronine (TT₃ ) and decreased nitric oxide in HT + NSE. Besides, it decreased TT₃ in HP + NSE and increased total antioxidant capacity. Our findings suggest that NSE may have beneficial effects on thyroid gland abnormalities owing to its antioxidant properties. PRACTICAL APPLICATIONS: Essential oils derived from Nigella sativa L. seed contain many bioactive substances such as thymoquinone and cymene. This paper emphasizes the effect of NSE on thyroid hormone abnormalities and negative oxidative state that occurs in HT and HP models. The present study provides evidence of a positive effect of NSE particularly on TT₃ levels in the HT and HP models. It can therefore be assumed that NSE could be used as a supportive natural alternative source to improve thyroid hormone levels and relieve increased oxidative stress.

In silico analysis of quranic and prophetic medicinals plants for the treatment of infectious viral diseases including corona virus

Coronavirus disease (COVID-19) is an infection of the respiratory system caused by single standard RNA viruses named as Severe Acute Respiratory Syndrome 2 (SARS-CoV-2). The disease appeared as a serious problem and the leading cause of death in human beings throughout the world. The main source of different phytochemicals are plants, which helps in the development of new drugs against various ailments. Islam is comprehensive religion and a complete code of life for Muslims. The teaching of Islam, according to the Holy Quran and Hadith are universal for the benefit of humanity. Islam believes that every ailment is from God and who made the disease definitely made its medication. There is a complete guideline with regard to taking measures against infectious diseases such as quarantine and seeking medicinal treatment. The research objective is to gather the knowledge of medicinal plants described in the Holy Quran or utilized by the Prophet (SAW) for the treatment of different ailments or advised to use them to boost immunity and strengthen the body. Scientists across the globe have found these plants beneficial for many diseases and have antiviral potential. In present study, the six plant species including Olea europaea, Nigella sativa, Allium Sativum, Allium cepa, Zingiber officinale and Cassia senna were selected which contain phytochemicals like Calcium Elenolate, Thymoquinone, S-Allylcysteine, Dipropyl Disulfide, Sesquiterpene, Monoterpene, Pelargonidin 3-Galactoside ion and Kaempferol. The phytochemicals monoterpene (from Zingiber officinale) shows best interaction with target proteins RdRP, 3CLPro, ACE2. Calcium Elonate (from olive) bonds with 3CLPro, ACE2 and Kemoferol and Pelargomidine (from Senna Makki) bonds with RdRP, ACE2. The ligands show a unique set of intersections i.e. hydrogen bonding, and alkyl interaction. These medicinal plants can be utilized immediately for the treatment of COVID-19 as their safety is already established. This treatment can enhance recovery when combined with other treatments. Furthermore, the screening of bioactive compounds or phytochemicals found in these plants can be utilized to design new therapeutic drug to treat COVID-19 pandemic.

Therapeutic Potentials of Antiviral Plants Used in Traditional African Medicine With COVID-19 in Focus: A Nigerian Perspective

The coronavirus disease 2019 (COVID-19) pandemic is caused by an infectious novel strain of coronavirus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which was earlier referred to as 2019-nCoV. The respiratory disease is the most consequential global public health crisis of the 21st century whose level of negative impact increasingly experienced globally has not been recorded since World War II. Up till now, there has been no specific globally authorized antiviral drug, vaccines, supplement or herbal remedy available for the treatment of this lethal disease except preventive measures, supportive care and non-specific treatment options adopted in different countries via divergent approaches to halt the pandemic. However, many of these interventions have been documented to show some level of success particularly the Traditional Chinese Medicine while there is paucity of well reported studies on the impact of the widely embraced Traditional African Medicines (TAM) adopted so far for the prevention, management and treatment of COVID-19. We carried out a detailed review of publicly available data, information and claims on the potentials of indigenous plants used in Sub-Saharan Africa as antiviral remedies with potentials for the prevention and management of COVID-19. In this review, we have provided a holistic report on evidence-based antiviral and promising anti-SARS-CoV-2 properties of African medicinal plants based on in silico evidence, in vitro assays and in vivo experiments alongside the available data on their mechanistic pharmacology. In addition, we have unveiled knowledge gaps, provided an update on the effort of African Scientific community toward demystifying the dreadful SARS-CoV-2 micro-enemy of man and have documented popular anti-COVID-19 herbal claims emanating from the continent for the management of COVID-19 while the risk potentials of herb-drug interaction of antiviral phytomedicines when used in combination with orthodox drugs have also been highlighted. This review exercise may lend enough credence to the potential value of African medicinal plants as possible leads in anti-COVID-19 drug discovery through research and development.

Thymoquinone, as a Novel Therapeutic Candidate of Cancers

To date, natural products are widely used as pharmaceutical agents for many human diseases and cancers. One of the most popular natural products that have been studied for anticancer properties is thymoquinone (TQ). As a bioactive compound of Nigella sativa, TQ has shown anticancer activities through the inhibition of cell proliferation, migration, and invasion. The anticancer efficacy of TQ is being investigated in several human cancers such as pancreatic cancer, breast cancer, colon cancer, hepatic cancer, cervical cancer, and leukemia. Even though TQ induces apoptosis by regulating the expression of pro- apoptotic and anti-apoptotic genes in many cancers, the TQ effect mechanism on such cancers is not yet fully understood. Therefore, the present review has highlighted the TQ effect mechanisms on several signaling pathways and expression of tumor suppressor genes (TSG). Data from relevant published experimental articles on TQ from 2015 to June 2020 were selected by using Google Scholar and PubMed search engines. The present study investigated the effectiveness of TQ alone or in combination with other anticancer therapeutic agents, such as tyrosine kinase inhibitors on cancers, as a future anticancer therapy nominee by using nanotechnology.

Thymoquinone supplementation ameliorates cisplatin-induced hepatic pathophysiology

Hepatotoxicity is a major dose-limiting side effect of CP chemotherapy besides nephrotoxicity and gastrointestinal dysfunction. TQ, a principal Nigella sativa seed oil constituent, has been shown to improve hepatic functions in various in vivo models of acute hepatic injury. In view of this, the present study aimed to evaluate the effect of TQ against CP-induced hepatotoxicity. Rats were divided into four experimental groups; control, CP, CP+TQ and TQ. Animals in CP+TQ and TQ groups were administered TQ (1.5 mg/kg bwt, orally), with or without a single hepatotoxic dose of CP (6 mg/kg bwt, i.p.) respectively, for 14 days before and four days following the CP treatment. CP induced an upsurge in serum ALT and AST activities, indicating liver injury, as also confirmed by the histopathological findings. CP caused significant alterations in the activities of membrane marker enzymes, carbohydrate metabolic enzymes, and the enzymatic and nonenzymatic components of the antioxidant defense system. TQ supplementation ameliorated all these adverse biochemical and histological changes in CP-treated rats. Thus, TQ may have excellent scope for clinical applications in combating CP-induced hepatic pathophysiology.

The effect of dietary supplementation with Nigella sativa (black seeds) mediates immunological function in male Wistar rats

This experiment aimed to investigate the effect of dietary Nigella sativa on the cell-mediated immune response. Eighteen male Wistar rats were divided equally into a control group and treated groups that received black seeds at rates of 30 and 50 g/kg in the diet (Sa30 and Sa50 groups, respectively, for 30 days. The weight gain, feed intake, feed conversion ratio (FCR), and cell-mediated immune response were monitored after the injection of 0.1 mL of 10% phytohemagglutinin (PHA). The intumesce index, serum total antioxidant capacity (TAC), catalase (CAT), interleukin-12 (IL-12), gamma interferon (γ-IF) and tumor necrosis factor alpha (TNF-α) were determined. Histopathological examination and an immunohistochemistry analysis of splenic caspase-3 and CD8 were performed. Nigella sativa significantly improved the weight gain and FCR. Intumesce index of Sa50 group was significantly increased. Nigella sativa significantly increased TAC, CAT, IL-12, γ-IF and TNF-α. A histological examination of PHA-stimulated foot pads showed increased leukocyte infiltration and edema in a dose-dependent pattern. Splenic caspase-3 and CD8 showed significant decreases and increases, respectively, in the Sa30 and Sa50 groups. The results indicate that Nigella sativa seeds exhibit immunostimulatory function through their antioxidant potential, induction of cytokine production, promotion of CD8 expression and reduction of splenic apoptosis.

Effects of Nigella sativa oil and thymoquinone on radiation-induced oxidative stress in kidney tissue of rats

Ionizing radiation leads to release of free radicals into the systemic circulation from irradiated tissues. These free radicals cause oxidative stress in distant organs. Oxidative status may be reversed by naturally occurring antioxidant agents. The aim of this study was to investigate protective and antioxidant effects of Nigella sativa oil (NSO) and thymoquinone (TQ) in kidney tissue of rats exposed to cranial irradiation. Forty-eight Sprague-Dawley rats were divided into six groups: IR group received irradiation (IR) to total cranium plus saline; IR plus NSO group received IR and NSO; IR plus TQ group received IR and TQ; sham group did not receive NSO, TQ or IR; control group of TQ received dimethyl sulfoxide; control group of NSO received saline. Total oxidant status (TOS), oxidative stress index (OSI) and lipid hydroperoxide (LOOH) levels were studied as oxidative parameters, and total antioxidant status (TAS), total sulfhydryl levels, paraoxonase (PON), ceruloplasmin (Cp) and arylesterase activities were determined as antioxidative parameters in the kidney tissue of rats. Kidney TOS, OSI and LOOH levels were significantly lower in IR plus TQ, IR plus NSO and sham groups compared to IR group (p < 0.001). TAS, PON and Cp activities in IR group were significantly lower compared to the control group (p < 0.001). PON and Cp activities were significantly higher in IR plus NSO and IR plus TQ groups compared to IR group (p < 0.001). In conclusion, free radicals generated by cranial ionizing radiation exposure cause oxidative stress in kidney. NSO and TQ exhibit protective and antioxidant effects against oxidative damage in rats.

Nigella sativa in controlling Type 2 diabetes, cardiovascular, and rheumatoid arthritis diseases: Molecular aspects

Oxidative stress is an important factor in the etiology of several chronic diseases that include cardiovascular disease (CVD), Type 2 diabetes (T2D), and rheumatoid arthritis (RA). Oxidative stress can lead to inflammation, and this can contribute to these chronic diseases. Reducing inflammation and oxidative stress may, therefore, be useful in the prevention and treatment of these conditions. One of the treatment options for chronic diseases is the use of traditional medicine and herbs, such as Nigella sativa. This is one of the herbs that have recently been assessed for its ability to reduce inflammation and oxidative stress. We have reviewed the reported effects of N. sativa on risk factors of chronic diseases (CVD, DM, and RA) with emphasis on molecular and cellular mechanisms in controlling inflammation and oxidative stress. Various mechanisms have been proposed to contribute to the beneficial properties of N. sativa, including a reduction of lipid peroxidation via its antioxidant properties; agonist of peroxisome proliferator-activated receptor gamma in adipose tissue; activation of AMP-activated protein kinase, increased antioxidants, inhibition of nuclear factor-kappa B pathway; increased in interleukin-10 expression, CD4+ T-cell percentage, T regulatory cell percentage (CD4+ CD25+ T-cell) in peripheral blood, and CD4+/CD8+ ratio, but to prove this claim, it is necessary to conduct experimental and well-designed clinical trial studies with a larger sample size on the effects of N. sativa on these chronic diseases.

Neuroprotective Effects of Thymoquinone by the Modulation of ER Stress and Apoptotic Pathway in In Vitro Model of Excitotoxicity

Experimental evidence indicates that the activation of ionotropic glutamate receptors plays an important role in neurological disorders’ models such as epilepsy, cerebral ischemia and trauma. The glutamate receptor agonist kainic acid (KA) induces seizures and excitotoxic cell death in the CA3 region of the hippocampus. Thymoquinone (TQ) is the most important component of the essential oil obtained from black cumin (Nigella sativa L.) seeds. It has many pharmacological actions including antioxidant, anti-inflammatory, and anti-apoptotic effects. TQ was used in an in vitro experimental model of primary cultures where excitotoxicity was induced. Briefly, rat organotypic hippocampal slices were exposed to 5 µM KA for 24 h. Cell death in the CA3 subregions of slices was quantified by measuring propidium iodide fluorescence. The cross-talk between TQ, ER stress and apoptotic pathways was investigated by Western blot. In untreated slices TQ (10 µM) induced a significant increase on the PSD95 levels and it decreased the excitotoxic injury induced by KA. Additionally, TQ was able to ameliorate the KA-induced increase in unfolded proteins GRP78 and GRP94 expression. Finally, TQ was able to partially rescue the reduction of the KA-induced apoptotic pathway activation. Our results suggest that TQ modulates the processes leading to post-kainate neuronal death in the CA3 hippocampal area.

Nigella sativa (Black Seed) as a Natural Remedy against Viruses

The currently available antiviral agents are associated with serious adverse effects, coupled with the increasing rate of viral resistance to the existing antiviral drugs. Hence, the search for alternative natural remedies is gaining momentum across the globe. Nigella sativa Linnen, also called Black seed, is a medicinal plant that is gaining worldwide recognition and has been extensively investigated. The present work is aimed to review the existing literature on the antiviral efficacy of Nigella sativa extracts (oil & bioactive compounds). The findings reveal that numerous articles have been published on Nigella sativa and its beneficial effects against different kinds of diseases. However, the antiviral efficacy of Nigella sativa is yet to be given the proper research attention it deserves.

An updated knowledge of Black seed (Nigella sativa Linn.): Review of phytochemical constituents and pharmacological properties

N. sativa (N. sativa) has been used since ancient times, when a scientific concept about the use of medicinal plants for the treatment of human illnesses and alleviation of their sufferings was yet to be developed. It has a strong religious significance as it is mentioned in the religious books of Islam and Christianity. In addition to its historical and religious significance, it is also mentioned in ancient medicine. It is widely used in traditional systems of medicine for a number of diseases including asthma, fever, bronchitis, cough, chest congestion, dizziness, paralysis, chronic headache, back pain and inflammation. The importance of this plant led the scientific community to carry out extensive phytochemical and biological investigations on N. sativa. Pharmacological studies on N. sativa have confirmed its antidiabetic, antitussive, anticancer, antioxidant, hepatoprotective, neuro-protective, gastroprotective, immunomodulator, analgesic, antimicrobial, anti-inflammatory, spasmolytic, and bronchodilator activity. The present review is an effort to explore the reported chemical composition and pharmacological activity of this plant. It will help as a reference for scientists, researchers, and other health professionals who are working with this plant and who need up to date knowledge about it.

The effects of Nigella sativa on respiratory, allergic and immunologic disorders, evidence from experimental and clinical studies, a comprehensive and updated review

Nigella sativa (N. sativa) seed had been used traditionally due to several pharmacological effects. The updated experimental and clinical effects of N. sativa and its constituents on respiratory, allergic and immunologic disorders are provided in this comprehensive review article. Various databases including PubMed, Science Direct and Scopus were used. The preventive effects of N. sativa on pulmonary diseases were mainly due to its constituents such as thymoquinone, thymol, carvacrol and alpha-hederin. Extracts and constituents of N. sativa showed the relaxant effect, with possible mechanisms indicating its bronchodilatory effect in obstructive pulmonary diseases. In experimental animal models of different respiratory diseases, the preventive effect of various extracts and constituents of N. sativa was demonstrated by mechanisms such as antioxidant, immunomodulatory and antiinflammatory effects. Bronchodilatory and preventive effects of the plant and its components on asthma, COPD and lung disorders due to exposure to noxious agents as well as on allergic and immunologic disorders were also shown in the clinical studies. Various extracts and constituents of N. sativa showed pharmacological and therapeutic effects on respiratory, allergic and immunologic disorders indicating possible remedy effect of that the plant and its effective substances in treating respiratory, allergic and immunologic diseases.

Thymoquinone Preserves Pancreatic Islets Structure Through Upregulation of Pancreatic β-Catenin in Hypothyroid Rats

BACKGROUND

Altered status of thyroid hormones, which have a key role in regulating metabolism, was reported to affect glucose homeostasis and insulin secretion.

OBJECTIVE

This study was designed to assess the impact of propylthiouracil (PTU)-induced hypothyroidism on the pancreatic islet cells and the efficacy of thymoquinone (TQ) in alleviating this impact and explore the mechanism behind it alleviating oxidative stress and affecting β-catenin expression.

MATERIALS AND METHODS

PTU (6 mg/kg/body weight) was used to induce hypothyroidism in Wistar rats. Four groups of rats (n=6 each) were utilized in this study. Untreated hypothyroid and TQ-treated hypothyroid groups (50 mg/kg/body weight for 4 weeks) were included. Thyroid functions, antioxidant profile and pancreatic β-catenin and IL-10 mRNA were measured. Histopathological and immunohistochemical assessment of the pancreas was performed.

RESULTS

PTU administration induced a hypothyroid status that was associated with a marked disturbed oxidant/antioxidant status and a significant hyperglycemia (p<0:001), hypoinsulinemia (p=0.01) and decreased HOMA-β-cell (p<0.001). Islet cells of hypothyroid pancreas showed many degenerative changes with increased apoptosis, reduced insulin β-catenin immunoexpression. Administration of TQ alleviated these effects on the thyroid function, antioxidants, structure of pancreatic islet cells. Up-regulation of β-catenin, IL-10 and CAT gene expression in pancreatic islets after treatment with TQ supported its antioxidant and preserving β-cell function and viability mechanistic action.

CONCLUSION

TQ alleviated PTU-induced hypothyroidism changes in insulin homeostasis and pancreatic β cells mostly through its antioxidant effect as well as up-regulation of pancreatic β-catenin expression.

Perspective Adjunctive Therapies for COVID-19: Beyond Antiviral Therapy

The coronavirus disease 2019 (COVID-19) pandemic is the largest health crisis ever faced worldwide. It has resulted in great health and economic costs because no effective treatment is currently available. Since infected persons vary in presentation from healthy asymptomatic mild symptoms to those who need intensive care support and eventually succumb to the disease, this illness is considered to depend primarily on individual immunity. Demographic distribution and disease severity in several regions of the world vary; therefore, it is believed that natural inherent immunity provided through dietary sources and traditional medicines could play an important role in infection prevention and disease progression. People can boost their immunity to prevent them from infection after COVID-19 exposure and can reduce their inflammatory reactions to protect their organ deterioration in case suffering from the disease. Some drugs with in-situ immunomodulatory and anti-inflammatory activity are also identified as adjunctive therapy in the COVID-19 era. This review discusses the importance of COVID-19 interactions with immune cells and inflammatory cells; and further emphasizes the possible pathways related with traditional herbs, medications and nutritional products. We believe that such pathophysiological pathway approach treatment is rational and important for future development of new therapeutic agents for prevention or cure of COVID-19 infection.

Nigella sativa and Thymoquinone: A Natural Blessing for Periodontal Therapy

Thymoquinone (TQ), the chief active constituent of Nigella sativa (NS), shows very valuable biomedical properties such as antioxidant, antimicrobial, anticancer, anti-inflammatory, antihypertensive, hypoglycemic, antiparasitic and anti-asthmatic effects. Several studies have examined the pharmacological actions of TQ in the treatment of oral diseases but its potential role in periodontal therapy and regeneration is not yet fully defined. The present investigation has been designed to review the scientific studies about the effects of TQ as an adjunct to periodontal treatment to promote healing and periodontal regeneration. Along with clinical experiments, in vitro studies exhibit the beneficial effects of TQ during periodontal therapy. Nevertheless, additional comprehensive clinical and preclinical studies at cellular and molecular levels are essential to examine the particular action mechanisms of Nigella sativa and its elements, particularly TQ, during periodontal treatment or regeneration.