Preclinical and clinical effects of Nigella sativa and its constituent, thymoquinone: A review

Impact of thymoquinone on the Nrf2/HO-1 and MAPK/NF-κB axis in mitigating 5-fluorouracil-induced acute kidney injury in vivo

Background

Chemotherapy-induced organ toxicity is one of the most common toxic effects of 5-fluorouracil (5-FU) in cancer patients. Therefore, new strategies are needed to prevent chemotherapy-induced kidney toxicity. Thymoquinone (TQ), a constituent of the plant Nigella sativa from the family Renunculaceae, has been found to be antiapoptotic, antioxidant, antimicrobial, anti-inflammatory, and protective against renal damage. This study aims to evaluate the effect of TQ in preventing nephrotoxicity induced by 5-FU treatment.

Method

Male albino Wistar rats were divided into four groups and administered saline (group I), 5-FU (150 mg/kg; group II), 5-FU+TQ (50 mg/kg; group III), and 5-FU+TQ (100 mg/kg; group IV). On the 21st day, rats were killed, and biochemical, histological, serological, and molecular analyses were conducted using kidney tissues and blood samples.

Results

5-FU induced kidney injury, as evidenced by alterations in kidney function markers (BUN, Cr, LDH, KIM-1), lipid peroxidation (LPO), ROS generation, histological changes, and a reduction in antioxidant defense mechanism (GSH, GR, GPx, and CAT). Additionally, 5-FU triggered crosstalk between Nrf2 and NF-κB/p38MAPK axis by significantly upregulating p-p38, p-JNK, p-ERK1/2, p-NF-κB, TNF-α, IL-1β, TGF-β, and IL-6, while downregulating Nrf2 and HO-1, resulting in kidney damage. Pre-, post-, and cotreatment with TQ alleviated kidney injury by replenishing antioxidant reserves, reducing serum toxicity, decreasing ROS generation and lipid peroxidation, downregulating p38 MAPK/NF-κB axis/pathway proteins, and upregulating Nrf2 and HO-1, thereby enhancing antioxidant axis and restoring kidney architecture.

Conclusion

Based on the results obtained in the present study, TQ appears to be a beneficial agent that could be used as an adjuvant therapy for the prevention of 5-FU-induced nephrotoxicity.

Mitigation of 5-Fluorouracil-Induced Nephrotoxicity: The Protective Role of Thymoquinone and Hesperidin <i>in vitro</i> and <i>in vivo</i>

Anticancer medications often lead to organ toxicity, affecting patients’ quality of life. Phytochemical compounds like Thymoquinone (TQ) and Hesperidin (HESP) have shown promise in mitigating anticancer drug-induced toxicity. However, their ability to protect against nephrotoxicity produced by 5- Fluorouracil (5-FU) remains unexplored. To assess the protective efficacy of TQ, HESP, and their combination against nephrotoxicity induced by 5-FU in both <i>in vitro</i> and <i>in vivo</i> settings. Human Embryonic Kidney (HEK293) cells were subjected to various concentrations of 5-FU, TQ, and HESP, with cell viability assessed using the MTT assay. Apoptosis was evaluated through Acridine orange-Ethidium bromide dual staining (AO- EB). <i>In vivo</i> experiments utilized male Wistar albino rats, which received treatments of 5-FU alone, in combination with TQ, HESP, and both. Subsequent biochemical and histological analyses were conducted on serum and kidney tissue samples. <i>In vitro</i> studies revealed dose- dependent cytotoxicity of 5-FU, while TQ and HESP showed minimal toxicity. Combination treatment significantly improved cell viability compared to 5-FU alone. <i>In vivo</i> studies indicated that the administration of 5-FU resulted in elevated levels of serum creatinine and blood urea nitrogen (BUN), suggestive of kidney dysfunction, which were attenuated by TQ, HESP, or their combination. TQ and HESP also restored antioxidant enzyme activity and reduced inflammatory markers in kidney tissues. Histological analysis showed significant protection against 5-FU- induced renal damage with combination therapy. Our findings suggest that TQ and HESP, alone or in combination, possess protective effects against 5-FU-induced nephrotoxicity, possibly through antioxidant and anti-inflammatory mechanisms. These results highlight the potential of herbal medicines as adjunctive therapies to mitigate chemotherapy-induced organ toxicity and improve patient outcomes. Additional investigation is necessary to clarify the fundamental molecular mechanisms involved and to corroborate these findings in clinical contexts.

Study on Volatile Organic Compounds and Antioxidant Polyphenols in Cumin Produced in Xinjiang

This article investigated the composition and content of volatile organic compounds (VOCs) in cumin from three Xinjiang origins (Hami, Turpan, and Hetian) at different processing temperatures. VOCs varied with temperature and origin, but alcohols and terpenes were predominant in all samples. Hetian cumin exhibited the highest VOC content and stability under specific treatments, divided into an ambient temperature treatment (AMB) and a 70 °C heat treatment. A cluster analysis revealed high similarity between replicates and significant differences among the samples. A Venn diagram comparison showed that 70 °C processing reduced the number of common VOCs among the three origins from 36 to 19, which is a decrease of 47.22%, indicating a significant impact of heating on cumin VOCs and possibly promoting the formation of new compounds. Finally, utilizing the varying abilities of different types of polyphenols to inhibit heterocyclic aromatic amines (HAAs), six polyphenolic compounds, identified as sesamin, 6-caffeoylsucrose, apigenin, eschweilenol C, kaempferol glucuronide, and luteolin, were preliminarily determined to play an active role in the β-carboline HAA simulation system.

Exploring druggable targets and inflammation-mediated pathways in cancer: a Mendelian randomization analysis integrating transcriptomic and proteomic data

BACKGROUND

Cancer remains a predominant global health challenge, necessitating the ongoing exploration of novel biomarkers and therapeutic targets to improve diagnosis and treatment.

METHODS

By integrating expression quantitative trait loci (eQTL) and protein quantitative trait loci (pQTL) data with genome-wide association studies (GWAS) data, we performed Mendelian randomization (MR) analysis to identify potential druggable targets at the gene expression and protein levels for multiple cancers. We conducted mediation analysis to explore whether inflammatory factors mediate the pathways linking identified druggable targets to cancer. Phenome-wide MR analysis, drug prediction, and molecular docking were employed to evaluate the medicinal potential.

RESULTS

We finally identified five druggable targets: CDKN1A, FES, and PDIA3 were associated with breast cancer, whereas TP53 and VAMP8 were associated with prostate cancer. Mediation analysis identified six inflammatory proteins as potential mediators in the causal pathways from these druggable targets to cancer: caspase 8, interleukin-1-alpha, C-X-C motif chemokine 1, C-C motif chemokine 23, TNF-related apoptosis-inducing ligand, and interleukin-6. Subsequent analyses further provided evidence supporting the pharmaceutical potential of these five targets.

CONCLUSIONS

Our study identified five druggable targets causally associated with breast and prostate cancers, with six inflammatory proteins acting as potential mediators, providing novel insights into the treatment of these cancers.

Nutritional enhancement in black seed (Nigella sativa L.) using bacteria-based biofertilizers

Nigella sativa L. is an aromatic spice, utilized as an original and peculiar flavoring ingredient in a variety of culinary applications and pharmaceuticals. Black seed (Nigella sativa L.) belongs to the family Ranunculaceae. It is an undercultivated crop in Pakistan. The present study was planned keeping in mind sustainable development goals SDG 3 (good health and well-being) and SDG 15 (life on land). The effects of several rhizospheric bacterial strains and synthetic fertilizers on the development of N. sativa and nutrition were studied using a completely randomized experimental design. For this purpose, plant growth-promoting effects of different strains (Azospirillum brasilense, Azospirillum lipoferum, and Pantoea agglomerans) and synthetic fertilizers (nitrogen and phosphorus) were assembled to check their effects individually and in combination form. Azospirillum lipoferum and Pantoea agglomerans inoculation significantly enhanced the morphological characteristics of N. sativa, whether applied individually or in combination, with positive effects on seedlings, plant height, number of branches, number of leaves, number of flowers, stamens numbers, follicles number, number of tentacles and seed production. N. sativa plants that were simultaneously inoculated with Azospirillum lipoferum and Pantoea agglomerans showed the highest potential for antioxidant activity, particularly in petroleum ether extracts. In the methanolic extract, a higher amount of radical scavenging was observed as compared to positive and negative control. There was also increase in fat, moisture and carbohydrate contents of the combination inoculated plant. So, from the present study, in Pakistan, the technique is recommended to enhance the yield and nutritional value of N. sativa.

Plant-Derived Natural Products for the Treatment of Bacterial Infections

Bacterial infections are a significant public health concern, and the emergence of antibiotic-resistant bacteria (ARB) has become a major challenge for modern medicine. The overuse and misuse of antibiotics have contributed to the development of ARB, which has led to the need for alternative therapies. Plant-derived natural products (PNPs) have been extensively studied for their potential as alternative therapies for the treatment of bacterial infections. The diverse chemical compounds found in plants have shown significant antibacterial properties, making them a promising source of novel antibacterial agents. The use of PNPs as antibacterial agents is particularly appealing because they offer a relatively safe and cost-effective approach to the treatment of bacterial infections. This chapter aims to provide an overview of the current state of research on PNPs as antibacterial agents. It will cover the mechanisms of action of the main PNPs against bacterial pathogens and discuss their potential to be used as complementary therapies to combat ARB. This chapter will also highlight the most common screening methodologies to discover new PNPs and the challenges and future prospects in the development of these compounds as antibacterial agents.

Thymoquinone loaded lipid nanocapsule dispersion: two methods of preparation, characterization and in vitro evaluations for oral administration

This work explores two methods to encapsulate Thymoquinone (TQ) into lipid nanocapsules (LNCs) for oral administration. TQ was added during the phase inversion temperature method (TQ-LNCs-1) or to unload LNCs dispersion (TQ-LNCs-2). LNCs were evaluated for mean diameter, polydispersity index (PDI), ζ-potential, drug loading (DL), drop tensiometer, storage stability, in vitro stability in simulated gastrointestinal fluids (SGIF), and intestinal permeability across Caco-2 cells. TQ-LNCs-1 and TQ-LNCs-2 produced NPs (58.3 ± 3.7 nm and 61.5 ± 3.5 nm, respectively), with a DL of 8.7 ± 0.2 and 7.7 ± 0.6 mg/mL of suspension, respectively. For both, less than 14% of TQ was released in SGIF, and a minor increase in TQ intestinal permeability with LNCs compared to free TQ was observed. TQ-LNCs represented a promising formulation for oral delivery of TQ. Encapsulation of TQ by adding it at LNCs dispersion can be extended for further drugs.

Alleviating effects of Nigella sativa supplements on biomarkers of inflammation and oxidative stress: Results from an umbrella meta-analysis

Several meta-analyses have examined the effect of Nigella sativa (N. Sativa) supplementation on inflammatory and oxidative markers, with conflicting results. So, the current study evaluated the effect of N. Sativa on some oxidative and inflammatory parameters. The Embase, Web of Science, Scopus, PubMed databases, and Google Scholar were systemically searched to identify papers indexed before February 2023. The pooled results were calculated with the use of a random-effects model to evaluate the effects of N. Sativa on inflammatory and oxidative markers. Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was used to assess the certainty of evidence. Overall, seven meta-analyses were included in the study. N. Sativa supplementation significantly decreased serum C-reactive protein (CRP) (ES = -0.42; 95 % CI: -0.58, -0.25, p < 0.001), tumor necrosis factor-alpha (TNF-α) (ES= -1.27; 95 % CI: -2.29, -0.25; p = 0.015), and malondialdehyde (MDA) (ES = -0.67; 95 % CI: -0.97, -0.36, p < 0.001) levels, and significantly improved total antioxidant capacity (TAC) (ES = 0.34; 95 % CI: 0.20, 0.47, p < 0.001) and superoxide dismutase (SOD) (ES = 50.66; 95 % CI: 34.15, 67.18, p < 0.001) levels. N. Sativa supplementation had beneficial effects on CRP, TNF-α, MDA, SOD, and TAC. Thus, N. Sativa can be recommended as an adjuvant anti-inflammatory and anti-oxidant agent.

Polymer lipid hybrid nanoparticles for phytochemical delivery: challenges, progress, and future prospects

Phytochemicals, naturally occurring compounds in plants, possess a wide range of therapeutic properties, including antioxidant, anti-inflammatory, anticancer, and antimicrobial activities. However, their clinical application is often hindered by poor water solubility, low bioavailability, rapid metabolism, and instability under physiological conditions. Polymer lipid hybrid nanoparticles (PLHNPs) have emerged as a novel delivery system that combines the advantages of both polymeric and lipid-based nanoparticles to overcome these challenges. This review explores the potential of PLHNPs to enhance the delivery and efficacy of phytochemicals for biomedical applications. We discuss the obstacles in the conventional delivery of phytochemicals, the fundamental architecture of PLHNPs, and the types of PLHNPs, highlighting their ability to improve encapsulation efficiency, stability, and controlled release of the encapsulated phytochemicals. In addition, the surface modification strategies to improve overall therapeutic efficacy by site-specific delivery of encapsulated phytochemicals are also discussed. Furthermore, we extensively discuss the preclinical studies on phytochemical encapsulated PLHNPs for the management of different diseases. Additionally, we explore the challenges ahead and prospects of PLHNPs regarding their widespread use in clinical settings. Overall, PLHNPs hold strong potential for the effective delivery of phytochemicals for biomedical applications. As per the findings from pre-clinical studies, this may offer a promising strategy for managing various diseases.

Antimicrobial Properties and Therapeutic Potential of Bioactive Compounds in Nigella sativa: A Review

Nigella sativa (N. sativa; Ranunculaceae), commonly referred to as black cumin, is one of the most widely used medicinal plants worldwide, with its seeds having numerous applications in the pharmaceutical and food industries. With the emergence of antibiotic resistance in pathogens as an important health challenge, the need for alternative microbe-inhibitory agents is on the rise, whereby black cumin has gained considerable attention from researchers for its strong antimicrobial characteristics owing to its high content in a wide range of bioactive compounds, including thymoquinone, nigellimine, nigellidine, quercetin, and O-cymene. Particularly, thymoquinone increases the levels of antioxidant enzymes that counter oxidative stress in the liver. Additionally, the essential oil in N. sativa seeds effectively inhibits intestinal parasites and shows moderate activity against some bacteria, including Bacillus subtilis and Staphylococcus aureus. Thymoquinone exhibits minimum inhibitory concentrations (MICs) of 8-16 μg/mL against methicillin-resistant Staphylococcus aureus (MRSA) and exhibits MIC 0.25 µg/mL against drug-resistant mycobacteria. Similarly, quercetin shows a MIC of 2 mg/mL against oral pathogens, such as Streptococcus mutans and Lactobacillus acidophilus. Furthermore, endophytic fungi isolated from N. sativa have demonstrated antibacterial activity. Therefore, N. sativa is a valuable medicinal plant with potential for medicinal and food-related applications. In-depth exploration of the corresponding therapeutic potential and scope of industrial application warrants further research.

Herbal Medicinal Nanoformulations for Psoriasis Treatment: Current State of Knowledge and Future Directions

Background:

Psoriasis is a persistent immune system disorder that influences the skin, leading to red, flaky patches that can be painful and irritated.

Objective:

Traditional treatments for psoriasis, such as topical creams and oral medications, may be effective but also have potential side effects. Herbal remedies have been used for centuries to treat skin conditions, and advancements in nanotechnology have led to the development of herbal nanoformulations that offer several advantages over traditional herbal remedies, such as efficacy, safety, and targeted delivery.

Methods:

The studies and reviews published under the title were looked up in several databases (including PubMed, Elsevier, and Google Scholar).

Results:

Several herbal nanoformulations, including those containing curcumin, aloe vera, and neem, have been shown to exhibit anti-inflammatory and immunomodulatory impacts, which will be useful within the treatment of psoriasis. However, more study is required to decide the efficacy and safety of these details, as well as the optimal dosing, duration of treatment, and potential side effects.

Conclusion:

Overall, herbal nanoformulations represent a promising area of research for the treatment of psoriasis, and may offer a safe and effective alternative or adjunct therapy to conventional treatments. This review article summarizes the present state of information for the herbal nanoformulations role in the treatment of psoriasis and their future perspectives.

Therapeutic Effects of Nigella sativa Oil and Whole Seeds on STZ-Induced Diabetic Rats: A Biochemical and Immunohistochemical Study

Background

Type II diabetes mellitus (DM) is an increasing health problem that has negative impacts on patients and healthcare systems, worldwide. The development of new therapies with better efficacy, fewer side effects, and lower prices are urgently needed to treat this disease.

Aim

To evaluate and compare the therapeutic effects of Nigella sativa (N. sativa) seed and oil on the biochemical parameters and regeneration of pancreatic islets (or islets of Langerhans) of streptozotocin (STZ)-induced diabetic rats.

Materials and Methods

The diabetic rat model was prepared by administering a single dose of STZ (35 mg/kg body weight). The whole seed or the oil of N. sativa was administered to the diabetic and control groups for a period of 28 days, but not to the negative and STZ controls. Serum blood glucose, liver enzymes, lipid profile, and renal function tests (uric acid, albumin, total protein, urea, and creatinine) were measured in all groups. After the rats were euthanized, their pancreases were extracted, and then sectioned and fixed on slides in preparation before staining with H&E stain and immunohistochemical study.

Results

Treatment of STZ-diabetic rats with N. sativa seeds or oil significantly improved their serum glucose levels, lipid profiles, and liver and renal functions as well as preserved the integrity of pancreatic β cells.

Conclusion

N. sativa seeds and oil demonstrate significant therapeutic improvement effects on DM and its related complications including effective protection of islets of Langerhans. The therapeutic benefits of N. sativa seeds and oil on DM and its related complications are comparable.

Characterization of chitosan/Persian gum nanoparticles for encapsulation of Nigella sativa extract as an antiviral agent against avian coronavirus

The aim of this study was to investigate the physicochemical characteristics of nanoparticles formed by the ionic gelation method between chitosan and water-soluble fraction of Persian gum (WPG) for encapsulation of Nigella sativa extract (NSE) as an antiviral agent. Our findings revealed that the particle size, polydispersity index (PDI), and zeta potential of the particles were in the range of 316.7-476.6 nm, 0.259-0.466, and 37.0-58.1 mV, respectively. The amounts of chitosan and WPG as the wall material and the NSE as the core had a considerable impact on the nanoparticle properties. The proper samples were detected at 1:1 chitosan:WPG mixing ratio (MR) and NSE concentration of 6.25 mg/mL. Fourier-transformed infrared (FTIR) spectroscopy proved the interactions between the two biopolymers. The effect of NSE on infectious bronchitis virus (IBV) known as avian coronavirus, was performed by the in-ovo method determining remarkable antiviral activity of NSE (25 mg/mL) and its enhancement through encapsulation in the nanoparticles. These nanoparticles containing NSE could have a promising capability for application in both poultry industry and human medicine as an antiviral product.

Designing novel industrial and functional foods using the bioactive compounds from Nigella sativa L. (black cumin): Biochemical and biological prospects toward health implications

Nigella sativa is one of the nutraceuticals that has gained popularity and studied extensively in recent decades as it is considered a safe medicinal plant for use as a dietary supplement. N. sativa contains a wide variety of bioactive substances, which include polyphenols, volatile oils (thymoquinone and p-cymene), proteins, and peptides. The biological attributes of N. sativa include antioxidant, antimicrobial, antifungal, anti-inflammatory, anticancer, antidiabetic, antihypertensive, hypolipidemic, and antioxidant activities, which have potential applications for the prevention of a variety of chronic diseases. In the food industry, N. sativa improves the sensory qualities, shelf life, strength, and freshness of foods, such as bread, pizza, biscuits, cookies, and cakes. This review discusses the industrial use of N. sativa, which includes processing technologies to enhance its health-promoting properties as well as the isolation of nutraceutical components.

Development and Characterization of Transdermal Patches Using Novel Thymoquinone-L-Arginine-Based Polyamide Nanocapsules for Potential Use in the Management of Psoriasis

Thymoquinone (TQ) is a phytochemical compound present in Nigella sativa and has potential benefits for treating dermatological conditions such as psoriasis. However, its clinical use is limited due to its restricted bioavailability, caused mainly by its low solubility and permeability. To overcome this, a new transdermal drug delivery system is required. Nanoparticles are known to enhance material solubility and permeability, and hence, this study aimed to synthesize TQ-loaded L-arginine-based polyamide (TQ/Arg PA) nanocapsules incorporated into transdermal patches for prolonged delivery of TQ. To achieve this, Eudragit E polymer, plasticizers, and aloe vera as penetration enhancer were used to develop the transdermal patch. Furthermore, novel TQ/Arg-PA was synthesized via interfacial polymerization, and the resultant nanocapsules (NCs) were incorporated into the matrix transdermal patch. The Arg-PA NCs' structure was confirmed via NMR and FTIR, and optimal TQ/Arg-PA NCs containing formulation showed high entrapment efficiency of TQ (99.60%). Molecular and thermal profiling of TQ/Arg-PA and the transdermal patch revealed the effective development of spherical NCs with an average particle size of 129.23 ± 18.22 nm. Using Franz diffusion cells and synthetic membrane (STRAT M®), the in vitro permeation profile of the prepared patches demonstrated an extended release of TQ over 24 h, with enhanced permeation by 42.64% when aloe vera was employed. In conclusion, the produced formulation has a potential substitute for corticosteroids and other drugs commonly used to treat psoriasis due to its effectiveness, safety, and lack of the side effects typically associated with other drugs.

Plant-Derived Substances for Prevention of Necrotising Enterocolitis: A Systematic Review of Animal Studies

Inflammation, oxidative injury, and gut dysbiosis play an important role in the pathogenesis of necrotising enterocolitis (NEC). Plant-derived substances have historically been used as therapeutic agents due to their anti-inflammatory, antioxidant, and antimicrobial properties. We aimed to review pre-clinical evidence for plant-derived substances in the prevention and treatment of NEC. A systematic review was conducted using the following databases: PubMed, EMBASE, EMCARE, MEDLINE and Cochrane Library (PROSPERO CRD42022365477). Randomized controlled trials (RCTs) and quasi-RCTs that evaluated a plant-derived substance as an intervention for NEC in an animal model of the illness and compared pre-stated outcomes (e.g., clinical severity, severity of intestinal injury, mortality, laboratory markers of inflammation and oxidative injury) were included. Sixteen studies (n = 610) were included in the systematic review. Ten of the sixteen included RCTs (Preterm rat pups: 15, Mice: 1) reported mortality and all reported NEC-related histology. Meta-analysis showed decreased mortality [12/134 vs. 27/135; RR: 0.48 (95% CI: 0.26 to 0.87); p = 0.02, 10 RCTs] and decreased NEC in the experimental group [24/126 vs. 55/79; RR: 0.34 (95% CI: 0.22 to 0.52); p < 0.001, 6 RCTs]. Markers of inflammation (n = 11) and oxidative stress (n = 13) improved in all the studies that have reported this outcome. There was no significant publication bias for the outcome of mortality. Plant-derived substances have the potential to reduce the incidence and severity of histologically diagnosed NEC and mortality in rodent models. These findings are helpful in guiding further pre-clinical studies towards developing a food supplement for the prevention of NEC in preterm infants.

Enhancement of Female Rat Fertility via Ethanolic Extract from Nigella sativa L. (Black Cumin) Seeds Assessed via HPLC-ESI-MS/MS and Molecular Docking

The characteristic chemical composition of Nigella seeds is directly linked to their beneficial properties. This study aimed to investigate the phytochemical composition of Nigella sativa seeds using a 100% ethanolic extract using HPLC-ESI-MS/MS. Additionally, it explored the potential biological effects of the extract on female rat reproduction. Follicle Stimulating Hormone (FSH), Luteinizing Hormone (LH), Estrogen (E2), and Progesterone (P4) hormone levels were also assessed, along with the morphological and histological effects of the extract on ovarian, oviductal, and uterine tissues. Molecular docking was performed to understand the extract's activity and its role in regulating female reproduction by assessing its binding affinity to hormonal receptors. Twenty metabolites, including alkaloids, saponins, terpenes, flavonoids, phenolic acids, and fatty acids, were found in the ethanolic extract of N. sativa seeds through the HPLC-ESI-MS/MS study. The N. sativa seed extract exhibited strong estrogenic and LH-like activities (p < 0.05) with weak FSH-like activity. Furthermore, it increased the serum levels of LH (p < 0.05), P4 hormones (p < 0.001), and E2 (p < 0.0001). Molecular docking results displayed a strong interaction with Erβ, LH, GnRH, and P4 receptors, respectively. Based on these findings, N. sativa seeds demonstrated hormone-like activities, suggesting their potential as a treatment for improving female fertility.

Chronic Treatment with Nigella sativa Oil Exerts Antimanic Properties and Reduces Brain Inflammation in Rats

Nigella sativa (NS) is a native herb consumed habitually in several countries worldwide, possessing manifold therapeutic properties. Among them, anti-inflammatory features have been reported, presumably relating to mechanisms involved in the nuclear factor kappa-B pathway, among others. Given the observed association between neuroimmune factors and mental illness, the primary aim of the present study was to examine the effects of chronic NS use on manic-like behavior in rats, as well as analyze levels of brain inflammatory mediators following NS intake. Using male and female rats, baseline tests were performed; thereafter, rats were fed either regular food (control) or NS-containing food (treatment) for four weeks. Following intervention, behavioral tests were induced (an open field test, sucrose consumption test, three-chamber sociality test, and amphetamine-induced hyperactivity test). Subsequently, brain samples were extracted, and inflammatory mediators were evaluated, including interleukin-6, leukotriene B4, prostaglandin E2, tumor necrosis factor-α, and nuclear phosphorylated-p65. Our findings show NS to result in a marked antimanic-like effect, in tandem with a positive modulation of select inflammatory mediators among male and female rats. The findings reinforce the proposed therapeutic advantages relating to NS ingestion.

Effect of Nigella sativa Intake on Oxidative Stress and Inflammation in Patients with Metabolic Syndrome and Related Disorders: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND

Several studies have shown that the intake of N. sativa has a beneficial effect on metabolic syndrome and related disorders. In this meta-analysis, our primary objective was to assess the impact of Nigella sativa consumption on inflammation and oxidative stress biomarkers among individuals diagnosed with metabolic syndrome and its associated conditions.

METHODS

Our search was conducted on prominent online databases such as Web of Science, Scopus, PubMed, and EMBASE, utilizing relevant keywords until August 2023.

RESULTS

This meta-analysis was performed on 16 RCTs comprising 1033 participants. Our results showed that intake of Nigella sativa significantly decreased CRP (SMD: -0.60; (95% CI: from -0.96 to -0.23); P = 0.00), TNF-α (SMD: -0.53; (95% CI: from -0.74 to -0.53); P = 0.00); IL-6 (SMD: -0.54 ; (95% CI: from -1.01 to -0.07); P = 0.02), and MDA: (SMD: -1.28; (95% CI: from -2.11 to -0.46); P = 0.00) levels. In addition, SOD: (SMD: 1.35; (95% CI, from 0.77 to 1.93); P = 0.00) and TAC (SMD: 2.82; (95% CI, from 0.55 to 5.084); P = 0.01) levels significantly increased in the intervention group compared to the placebo group.

CONCLUSION

Our results showed that THE consumption of N. sativa could be associated with improved oxidative stress and inflammation in patients with metabolic syndrome and related disorders.

Thymoquinone-loaded self-nano-emulsifying drug delivery system against ischemia/reperfusion injury

In the present study, a self-nano-emulsifying drug delivery system (SNEDDS) was developed to evaluate the efficiency of thymoquinone (TQ) in hepatic ischemia/reperfusion. SNEDDS was pharmaceutically characterized to evaluate droplet size, morphology, zeta potential, thermodynamic stability, and dissolution/diffusion capacity. Animals were orally pre-treated during 10 days with TQ-loaded SNEDDS. Biochemical analyses, hematoxylin-eosin staining, indirect immunofluorescence, and reverse transcription polymerase chain reaction (RT-PCR) were carried out to assess cell injury, oxidative stress, inflammation, and apoptosis. The TQ formulation showed good in vitro characteristics, including stable nanoparticle structure and size with high drug release rate. In vivo determinations revealed that TQ-loaded SNEDDS pre-treatment of rats maintained cellular integrity by decreasing transaminase (ALT and AST) release and preserving the histological characteristics of their liver. The antioxidant ability of the formulation was proven by increased SOD activity, reduced MDA concentration, and iNOS protein expression. In addition, this formulation exerted an anti-inflammatory effect evidenced by reduced plasma CRP concentration, MPO activity, and gene expressions of TLR-4, TNF-α, NF-κB, and IL-6. Finally, the TQ-loaded SNEDDS formulation promoted cell survival by enhancing the Bcl-2/Bax ratio. In conclusion, our results indicate that TQ encapsulated in SNEDDS significantly protects rat liver from I/R injury.

Immunomodulatory Effect of Phytoactive Compounds on Human Health: A Narrative Review Integrated with Bioinformatics Approach

BACKGROUND

Immunomodulation is the modification of immune responses to control disease progression. While the synthetic immunomodulators have proven efficacy, they are coupled with toxicity and other adverse effects, and hence, the efforts were to identify natural phytochemicals with immunomodulatory potential.

OBJECTIVE

To understand the immunomodulatory properties of various phytochemicals and investigate them in Echinacea species extracts using an in silico approach.

METHODOLOGY

Several scientific database repositories were searched using different keywords: "Phytochemicals," "Alkaloids," "Polyphenols," "Flavonoids," "Lectins," "Glycosides," "Tannins," "Terpenoids," "Sterols," "Immunomodulators," and "Human Immune System" without any language restriction. Additionally, the study specifically investigated the immunomodulatory properties of Echinacea species extracts using gene expression analysis of GSE12259 from NCBI-GEO through the Bioconductor package GEOquery and limma.

RESULTS

A total of 182 studies were comprehensively analyzed to understand immunomodulatory phytochemicals. The in silico analysis highlighted key biological processes (positive regulation of cytokine production, response to tumor necrosis factor) and molecular functions (cytokine receptor binding, receptor-ligand activity, and cytokine activity) among Echinacea species extracts contributing to immune responses. Further, it also indicated the association of various metabolic pathways, i.e., pathways in cancer, cytokine-cytokine receptor interaction, NF-kappa B, PI3K-Akt, TNF, MAPK, and NOD-like receptor signaling pathways, with immune responses. The study revealed various hub targets, including CCL20, CCL4, GCH1, SLC7A11, SOD2, EPB41L3, TNFAIP6, GCLM, EGR1, and FOS.

CONCLUSION

The present study presents a cumulative picture of phytochemicals with therapeutic benefits. Additionally, the study also reported a few novel genes and pathways in Echinacea extracts by re-analyzing GSE 12259 indicating its anti-inflammatory, anti-viral, and immunomodulatory properties.

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.

Assessing Galleria mellonella as a preliminary model for systemic Staphylococcus aureus infection: Evaluating the efficacy and impact of vancomycin and Nigella sativa oil on gut microbiota

Background

Staphylococcus aureus is a Gram-positive bacterium that can cause various infections. The Galleria mellonella has been used as a preliminary test for infection model. The study aimed to evaluate the effectiveness of G. mellonella as a microbiome model and compare the efficacy of vancomycin and antimicrobial activity of Nigella sativa (NS) on the gut flora.

Methods

G. mellonella larvae were subjected to metagenomic analysis. The larvae's guts were collected, homogenized in phosphate-buffered saline (PBS), and the gut contents isolated for bacterial DNA extraction. Larvae were assigned into the following groups: negative control (PBS only); positive control (MRSA only); vancomycin treated group; NS oil treated group and combination (vancomycin and NS oil) treated group. Larvae were cultured, inoculated with S. aureus, and treated with vancomycin and NS oil. Larval activity, cocoon formation, growth, melanization, and survival were monitored. The toxicity of vancomycin and NS oil was tested, and S. aureus burden and natural microbiota were determined. Hemocyte density was measured. Statistical analysis was conducted using R.

Results

Enterococcus related species dominated approximately 90 % of the gastrointestinal tract of the larvae. The survival rate following treatment was 85 % with vancomycin, 64 % with NS oil, and 73 % with a combination of both. The count of Enterococcus Colony Forming Units (CFUs) was significantly lower in the vancomycin treatment group (8.14E+04) compared to those treated with NS oil (1.97E+06) and the combination treatment (8.95E+05). Furthermore, the S. aureus burden was found to be lower in the NS oil (1.04E+06) and combination treatment groups (9.02E+05) compared to the vancomycin treatment group (3.38E+06). Hemocyte densities were significantly higher in the NS oil (8.29E+06) and combination treatment groups (8.18E+06) compared to the vancomycin treatment group (4.89E+06).

Conclusions

The study supported the use of G. mellonella model as a preliminary test to assess the effect of different antimicrobials against S. aureus and gut microbiota. NS oil showed more selectivity against S. aureus and protectiveness for the natural Enterococcus gut flora.

How Thymoquinone from Nigella sativa Accelerates Wound Healing through Multiple Mechanisms and Targets

Wound healing is a multifaceted process necessitating the collaboration of numerous elements to mend damaged tissue. Plant and animal-derived natural compounds have been utilized for wound treatment over the centuries, with many scientific investigations examining these compounds. Those with antioxidant, anti-inflammatory, and antibacterial properties are particularly noteworthy, as they target various wound-healing stages to expedite recovery. Thymoquinone, derived from Nigella sativa (N. sativa)-a medicinal herb with a long history of use in traditional medicine systems such as Unani, Ayurveda, Chinese, and Greco-Arabic and Islamic medicine-has demonstrated a range of therapeutic properties. Thymoquinone exhibits antimicrobial, anti-inflammatory, and antineoplastic activities, positioning it as a potential remedy for skin pathologies. This review examines recent research on how thymoquinone accelerates wound healing and the mechanisms behind its effectiveness. We carried out a comprehensive review of literature and electronic databases, including Google Scholar, PubMed, Science Direct, and MedlinePlus. Our aim was to gather relevant papers published between 2015 and August 2023. The main criteria for inclusion were that the articles had to be peer reviewed, original, written in English, and discuss the wound-healing parameters of thymoquinone in wound repair. Our review focused on the effects of thymoquinone on the cellular and molecular mechanisms involved in wound healing. We also examined the role of cytokines, signal transduction cascades, and clinical trials. We found sufficient evidence to support the effectiveness of thymoquinone in promoting wound healing. However, there is no consensus on the most effective concentrations of these substances. It is therefore essential to determine the optimal treatment doses and the best route of administration. Further research is also needed to investigate potential side effects and the performance of thymoquinone in clinical trials.

Thymoquinone attenuates olanzapine-induced metabolic disorders in rats

BACKGROUND

Olanzapine (OLZ) is an atypical antipsychotic agent for psychotic disorders. Evidence has shown that OLZ is related to metabolic side effects, including obesity, hypertension, and insulin resistance. Thymoquinone (TQ) is the principal bioactive component of Nigella sativa. Several studies have been conducted to investigate the effectiveness of TQ in alleviating metabolic abnormalities. In the current research work, the protective effects of TQ on metabolic disorders induced by OLZ and possible underlying mechanisms were investigated.

METHODS AND RESULTS

Wistar rats were exposed to TQ alone (10 mg/kg), OLZ (5 mg/kg), or OLZ plus TQ (2.5, 5, or 10 mg/kg) given daily by intraperitoneal injection. After the treatment, variations in body weight, food intake, systolic blood pressure, serum leptin, biochemical factors, liver malondialdehyde (MDA), and glutathione (GSH) content were evaluated. Protein expression of AMPK in the liver was also measured by a western blotting test. OLZ increased body weight, food intake, MDA levels, and blood pressure. OLZ also elevated glucose, triglyceride, low-density lipoprotein cholesterol, and leptin serum levels. It decreased GSH. In the western blot, decreased AMPK protein level was obtained. These changes were attenuated by TQ co-administration.

CONCLUSIONS

The present study demonstrates the effectiveness of TQ on OLZ-induced metabolic abnormalities related to its antioxidant activity and regulation of glucose homeostasis and lipid metabolism.

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.

Mechanism of the antidiabetic action of Nigella sativa and Thymoquinone: a review

Introduction

Long used in traditional medicine, Nigella sativa (NS; Ranunculaceae) has shown significant efficacy as an adjuvant therapy for diabetes mellitus (DM) management by improving glucose tolerance, decreasing hepatic gluconeogenesis, normalizing blood sugar and lipid imbalance, and stimulating insulin secretion from pancreatic cells. In this review, the pharmacological and pharmacokinetic properties of NS as a herbal diabetes medication are examined in depth, demonstrating how it counteracts oxidative stress and the onset and progression of DM.

Methods

This literature review drew on databases such as Google Scholar and PubMed and various gray literature sources using search terms like the etiology of diabetes, conventional versus herbal therapy, subclinical pharmacology, pharmacokinetics, physiology, behavior, and clinical outcomes.

Results

The efficiency and safety of NS in diabetes, notably its thymoquinone (TQ) rich volatile oil, have drawn great attention from researchers in recent years; the specific therapeutic dose has eluded determination so far. TQ has anti-diabetic, anti-inflammatory, antioxidant, and immunomodulatory properties but has not proved druggable. DM's intimate link with oxidative stress, makes NS therapy relevant since it is a potent antioxidant that energizes the cell's endogenous arsenal of antioxidant enzymes. NS attenuates insulin resistance, enhances insulin signaling, suppresses cyclooxygenase-2, upregulates insulin-like growth factor-1, and prevents endothelial dysfunction in DM.

Conclusion

The interaction of NS with mainstream drugs, gut microbiota, and probiotics opens new possibilities for innovative therapies. Despite its strong potential to treat DM, NS and TQ must be examined in more inclusive clinical studies targeting underrepresented patient populations.

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.

Antinociceptive Action of Thymoquinone-Loaded Liposomes in an In Vivo Model of Tendinopathy

Tendinopathies represent about 45% of musculoskeletal lesions and they are a big burden in clinics characterized by activity-related pain, focal tendon tenderness and intra-tendinous imaging changes. Many approaches have been proposed for tendinopathies' management (e.g., nonsteroidal anti-inflammatory drugs, corticosteroids, eccentric exercises, laser therapy), unfortunately with very little support of efficacy or serious side effects, thus making the identification of new treatments fundamental. The aim of the study was to test the protective and pain reliever effect of thymoquinone (TQ)-loaded formulations in a rat model of tendinopathy induced by carrageenan intra-tendon injection (20 µL of carrageenan 0.8% on day 1). Conventional (LP-TQ) and hyaluronic acid (HA)-coated TQ liposomes (HA-LP-TQ) were characterized and subjected to in vitro release and stability studies at 4 °C. Then, TQ and liposomes were peri-tendon injected (20 µL) on days 1, 3, 5, 7 and 10 to evaluate their antinociceptive profile using mechanical noxious and non-noxious stimuli (paw pressure and von Frey tests), spontaneous pain (incapacitance test) and motor alterations (Rota rod test). Liposomes containing 2 mg/mL of TQ and covered with HA (HA-LP-TQ2) reduced the development of spontaneous nociception and hypersensitivity for a long-lasting effect more than the other formulations. The anti-hypersensitivity effect matched with the histopathological evaluation. In conclusion, the use of TQ encapsulated in HA-LP liposomes is suggested as a new treatment for tendinopathies.

Synergistic Effects of Nigella sativa and Exercise on Diabetic Profiles: A Systematic Review

Individually, Nigella sativa (NS) and physical training interventions have been shown to be effective preventive and therapeutic strategies for diabetes mellitus. However, the effect of these in combination on bioindicators of diabetes has not yet been evaluated; there is little information available in the literature. A systematic review was therefore performed to assess any mutually potentiating impacts of NS and physical training interventions in diabetic subjects. A search was performed on this topic in the PubMed, CINAHL, Google Scholar and Web of Science databases for randomised, quasi-randomised or non-randomised controlled trials, studies with factorial or single-cohort pre-post designs, case series as well as case reports. The search terms encompassed various combinations of the following: "exercise", "training", "physical activity", "NS", "treadmill", "swimming", "Thymoquinone", "Nigellone", "caraway oil" and "black seeds". Two reviewers screened the abstracts of 202 identified publications according to predetermined inclusion criteria-i.e. papers published from 2009 onwards in the English language, studies on human or animal subjects, and the assessment of diabetic bioindicators following the combined administration of NS and exercise regimens in comparison with just one of these interventions or against controls. Despite the rich data available regarding the effect of both interventions separately, two human studies and two animal studies were ultimately included in the review. However, the benefit of combined administration of NS and exercise regimens on glycemic and lipidemic control was much more obvious compared to exercise alone. In conclusion, these findings suggested that combined administration of NS and exercise regimens could be used as an effective adjuvant for oral antidiabetic drugs in diabetes control.

A comprehensive perspective of traditional Arabic or Islamic medicinal plants as an adjuvant therapy against COVID-19

COVID-19 is a pulmonary disease caused by SARS-CoV-2. More than 200 million individuals are infected by this globally. Pyrexia, coughing, shortness of breath, headaches, diarrhoea, sore throats, and body aches are among the typical symptoms of COVID-19. The virus enters into the host body by interacting with the ACE2 receptor. Despite many SARS-CoV-2 vaccines manufactured by distinct strategies but any evidence-based particular medication to combat COVID-19 is not available yet. However, further research is required to determine the safety and effectiveness profile of the present therapeutic approaches. In this study, we provide a summary of Traditional Arabic or Islamic medicinal (TAIM) plants' historical use and their present role as adjuvant therapy for COVID-19. Herein, six medicinal plants Aloe barbadensis Miller, Olea europaea, Trigonella foenum-graecum, Nigella sativa, Cassia angustifolia, and Ficus carica have been studied based upon their pharmacological activities against viral infections. These plants include phytochemicals that have antiviral, immunomodulatory, antiasthmatic, antipyretic, and antitussive properties. These bioactive substances could be employed to control symptoms and enhance the development of a possible COVID-19 medicinal synthesis. To determine whether or if these TAIMs may be used as adjuvant therapy and are appropriate, a detailed evaluation is advised.

Honey and Nigella sativa against COVID-19 in Pakistan (HNS-COVID-PK): A multicenter placebo-controlled randomized clinical trial

Until now, no specific and effective treatment exists for coronavirus disease 2019 (COVID-19). Since honey and Nigella sativa (HNS) have established antiviral, antibacterial, antiinflammatory, antioxidant, and immunomodulatory properties, we tested their efficacy for this disease in a multicenter, placebo-controlled, and randomized clinical trial at four medical care facilities in Pakistan. RT-PCR confirmed COVID-19 adults showing moderate or severe disease were enrolled in the trial. Patients were randomly assigned in a 1:1 ratio to receive either honey (1 g kg^-1  day^-1 ) and Nigella sativa seeds (80 mg kg^-1  day^-1 ) or a placebo for up to 13 days along with standard care. The outcomes included symptoms' alleviation, viral clearance, and 30-day mortality in the intention-to-treat population. Three hundred and thirteen patients, 210 with moderate and 103 with severe disease, underwent randomization from April 30 to July 29, 2020. Among the moderate cases, 107 were assigned to HNS, whereas 103 were assigned to the placebo group. Among the severe cases, 50 were given HNS, and 53 were given the placebo. HNS resulted in ~50% reduction in time taken to alleviate symptoms as compared to placebo (moderate cases: 4 vs. 7 days, Hazard Ratio [HR]: 6.11; 95% Confidence Interval [CI]: 4.23-8.84, p < 0.0001 and for severe cases: 6 vs. 13 days, HR: 4.04; 95% CI: 2.46-6.64; p < 0.0001). HNS also cleared the virus earlier than placebo in both moderate cases (6 vs. 10 days, HR: 5.53; 95% CI: 3.76-8.14, p < 0.0001) and severe cases (8.5 vs. 12 days, HR: 4.32; 95% CI: 2.62-7.13, p < 0.0001). HNS further led to a better clinical score on day 6 with normal activity resumption in 63.6% vs. 10.9% among moderate cases (OR: 0.07; 95% CI: 0.03-0.13, p < 0.0001) and hospital discharge in 50% versus 2.8% in severe cases (OR: 0.03; 95% CI: 0.01-0.09, p < 0.0001). In severe cases, the mortality rate was less than 1/4th in the HNS group than in placebo (4% vs. 18.87%, OR: 0.18; 95% CI: 0.02-0.92, p = 0.029). No HNS-related adverse effects were observed. HNS, compared with placebo, significantly improved symptoms, expedited viral load clearance, and reduced mortality in COVID-19 patients. This trial was registered on April 15, 2020 with ClinicalTrials.gov Identifier: NCT04347382.

Nutraceuticals as Supportive Therapeutic Agents in Diabetes and Pancreatic Ductal Adenocarcinoma: A Systematic Review

The correlation between pancreatic ductal adenocarcinoma (PDAC) and diabetes-related mechanisms support the hypothesis that early therapeutic strategies targeting diabetes can contribute to PDAC risk reduction and treatment improvement. A systematic review was conducted, using PubMed, Embase and Cochrane Library databases, to evaluate the current evidence from clinical studies qualitatively examining the efficacy of four natural products: Curcumin-Curcuma longa L.; Thymoquinone-Nigella sativa L.; Genistein-Glycine max L.; Ginkgo biloba L.; and a low-carbohydrate ketogenic diet in type 2 diabetes (T2D) and PDAC treatment. A total of 28 clinical studies were included, showing strong evidence of inter-study heterogeneity. Used as a monotherapy or in combination with chemo-radiotherapy, the studied substances did not significantly improve the treatment response of PDAC patients. However, pronounced therapeutic efficacy was confirmed in T2D. The natural products and low-carbohydrate ketogenic diet, combined with the standard drugs, have the potential to improve T2D treatment and thus potentially reduce the risk of cancer development and improve multiple biological parameters in PDAC patients.

Saudi Arabian Plants: A Powerful Weapon against a Plethora of Diseases

The kingdom of Saudi Arabia (SA) ranks fifth in Asia in terms of area. It features broad biodiversity, including interesting flora, and was the historical origin of Islam. It is endowed with a large variety of plants, including many herbs, shrubs, and trees. Many of these plants have a long history of use in traditional medicine. The aim of this review is to evaluate the present knowledge on the plants growing in SA regarding their pharmacological and biological activities and the identification of their bioactive compounds to determine which plants could be of interest for further studies. A systematic summary of the plants' history, distribution, various pharmacological activities, bioactive compounds, and clinical trials are presented in this paper to facilitate future exploration of their therapeutic potential. The literature was obtained from several scientific search engines, including Sci-Finder, PubMed, Web of Science, Google Scholar, Scopus, MDPI, Wiley publications, and Springer Link. Plant names and their synonyms were validated by 'The Plant List' on 1 October 2021. SA is home to approximately 2247 plant species, including native and introduced plants that belong to 142 families and 837 genera. It shares the flora of three continents, with many unique features due to its extreme climate and geographical and geological conditions. As plants remain the leading supplier of new therapeutic agents to treat various ailments, Saudi Arabian plants may play a significant role in the fight against cancer, inflammation, and antibiotic-resistant bacteria. To date, 102 active compounds have been identified in plants from different sites in SA. Plants from the western and southwestern regions have been evaluated for various biological activities, including antioxidant, anti-cancer, antimicrobial, antimalarial, anti-inflammatory, anti-glycation, and cytotoxic activities. The aerial parts of the plants, especially the leaves, have yielded most of the bioactive compounds. Most bioactivity tests involve in vitro assessments for the inhibition of the growth of tumour cell lines, and several compounds with in vitro antitumour activity have been reported. More in-depth studies to evaluate the mode of action of the compounds are necessary to pave the way for clinical trials. Ecological and taxonomical studies are needed to evaluate the flora of SA, and a plan for the conservation of wild plants should be implemented, including the management of the protection of endemic plants.

Experimental and clinical trial investigations of phyto-extracts, phyto-chemicals and phyto-formulations against oral lichen planus: A systematic review

ETHNOPHARMACOLOGICAL RELEVANCE

Bio-assay guided phytoextracts and derived phytoconstituents reported having multipotent biological activities and nearly 60-80% of the global population still using natural regimens as an alternative therapeutic source. This study focused on the ethnopharmacological and experimental evidence of natural remedies that are effective in treating oral lichen planus (OLP), a chronic T-cell mediated autoimmune disease that is associated with oral cancer transmission.

AIM OF THE REVIEW

A number of studies have shown that antioxidants and antiinflammatory phytoextracts and phyto-constituents are effective against OLP. In this systematic review, we summarize the details of experimentally assessed ancient Traditional Chinese Medicine (TCM), Indian Ayurveda or Ayurvedic Medicine, and Japanese Kampo Medicine (JKM) regimens (crude extracts, individual phytochemicals, and phyto-formulations) that reduce oral lesion, severity index and pain associated with OLP based on studies conducted in vivo, in vitro, and in randomized controlled trials (RCTs).

MATERIALS AND METHODS

Experimental, clinical and RCT investigation reports were gathered and presented according to PRISMA-2020 format. Briefly, the information was obtained from PubMed, ScienceDirect, Wiley journal library, Scopus, Google Scholar with ClinicalTrials.gov (a clinical trial registry database operated by the National Library of Medicine in the United States). Further, individual phytochemical structures were verified from PubChem and ChemSpider databases and visualized by ChemDraw 18.0 software.

RESULTS

We summarized 11 crude phytoextracts, 7 individual phytochemicals, 9 crude formulations, 8 specific TCM and JKM herbal cocktails, and 6 RCTs/patents corroborated by multiple in vitro, in vivo and enzyme assay methods. Briefly, plants and their family name, used plant parts, reported phytochemicals and their chemical structure, treatment doses, and duration of each experiment were presented more concisely and scientifically.

CONCLUSION

Documentation of evidence-based natural ethnomedicines or remedies could be useful for promoting them as potential, cost-effective and less toxic alternatives or as complementary to commonly prescribed steroids towards the control of OLP.

The Role of Thymoquinone in Inflammatory Response in Chronic Diseases

Anti-inflammatory therapies have been shown to be effective in the prevention of various cardiovascular diseases, tumors, and cancer complications. Thymoquinone (TQ), the main active constituent of Nigella sativa, has shown promising therapeutic properties in many in vivo and in vitro models. However, TQ has poor bioavailability and is hydrophobic, prohibiting clinical trials with TQ alone. Studies have explored the combination of TQ with biological nanomaterials to improve its bioavailability. The TQ nanoparticle formulation shows better bioavailability than free TQ, and these formulations are ready for clinical trials to determine their potential as therapeutic agents. In this paper, we review current knowledge about the interaction between TQ and the inflammatory response and summarize the research prospects in Korea and abroad. We discuss the different biological activities of TQ and various combination therapies of TQ and nanomaterials in clinical trials.

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.

Progress in the treatment of drug-induced liver injury with natural products

There are numerous prescription drugs and non-prescription drugs that cause drug-induced liver injury (DILI), which is the main cause of liver disease in humans around the globe. Its mechanism becomes clearer as the disease is studied further. For an instance, when acetaminophen (APAP) is taken in excess, it produces N-acetyl-p-benzoquinone imine (NAPQI) that binds to biomacromolecules in the liver causing liver injury. Treatment of DILI with traditional Chinese medicine (TCM) has shown to be effective. For example, activation of the Nrf2 signaling pathway as well as regulation of glutathione (GSH) synthesis, coupling, and excretion are the mechanisms by which ginsenoside Rg1 (Rg1) treats APAP-induced acute liver injury. Nevertheless, reducing the toxicity of TCM in treating DILI is still a problem to be overcome at present and in the future. Accumulated evidences show that hydrogel-based nanocomposite may be an excellent carrier for TCM. Therefore, we reviewed TCM with potential anti-DILI, focusing on the signaling pathway of these drugs' anti-DILI effect, as well as the possibility and prospect of treating DILI by TCM based on hydrogel materials in the future. In conclusion, this review provides new insights to further explore TCM in the treatment of DILI.

Thymoquinone Produces Cardioprotective Effect in β-Receptor Stimulated Myocardial Infarcted Rats via Subsiding Oxidative Stress and Inflammation

Earlier studies reported that long-term treatment with thymoquinone (TQ) at a high dose (20 mg/kg) exerts a cardioprotective effect against isoproterenol (ISO)-triggered myocardial infarction (MI) in rats. In the present study, we tested the hypothesis that TQ, as a potent molecule, can exhibit cardioprotective effects at the lower dose for a short-term regimen. The rats were administered with TQ (5 mg/kg, intraperitoneal) at the 4 h interval for 2 days. ISO (100 mg/kg/day, subcutaneous) was given for 2 days to produce MI. ISO challenge results in deformation in ECG wave front, elevated left ventricular (LV) end-diastolic pressure, and reduced LVdP/dtmax and LVdP/dtmin. The levels of the cardiac biomarker in serum, such as creatine kinase MB, alanine aminotransferase, and aspartate aminotransferase, were increased. In the myocardium, a rise in malonaldehyde and decreased superoxide dismutase, glutathione, and catalase contents were observed. Furthermore, increased levels of tumor necrotic factor-α, interleukin-6, and interleukin-1β were observed in the myocardium. TQ pretreatment significantly normalized alterations in hemodynamic parameters, strengthened the antioxidant defense system, and decreased the contents of pro-inflammatory cytokines and hepatic enzymes as compared to the ISO group. Based on the results, TQ appears to be cardioprotective at low doses, and effective even administered for a shorter duration.

The Effects of a Transgelin-2 Agonist Administered at Different Times in a Mouse Model of Airway Hyperresponsiveness

Airway hyperresponsiveness (AHR) is one of the most important features of asthma. Our previous study showed that inhaled transgelin-2 agonist, TSG12, effectively reduced pulmonary resistance in a mouse model of asthma in a dose-dependent manner. However, the optimal administration time of TSG12 to reduce AHR and the pharmacological effects are still unclear. In this study, the effects of TSG12 inhalation before and during AHR occurrence were examined. The results showed that the pulmonary resistance was reduced by 57% and the dynamic compliance was increased by 46% in the TSG12 Mch group (atomize TSG12 10 min before methacholine, p &lt; 0.05 vs. model). The pulmonary resistance was reduced by 61% and the dynamic compliance was increased by 47% in the TSG12 + Mch group (atomize TSG12 and methacholine together, p &lt; 0.05 vs. model). Quantitative real-time PCR showed that the gene expression levels of transgelin-2, myosin phosphatase target subunit-1, and myosin light chain were up-regulated by 6.4-, 1.9-, and 2.8-fold, respectively, in the TSG12 Mch group. The gene expression levels of transgelin-2, myosin phosphatase target subunit-1, and myosin light chain were up-regulated by 3.2-, 1.4-, and 1.9-fold, respectively, in the TSG12 + Mch group. The results suggested that TSG12 effectively reduces pulmonary resistance when TSG12 inhalation occurred both before and during AHR occurrence. Gene expression levels of transgelin-2 and myosin light chain were significantly up-regulated when TSG12 inhalation occurred before AHR occurrence. This study may provide a basis for the administration time of TSG12 for asthma treatment in the future.

The Immunomodulatory Effects of Active Ingredients From Nigella sativa in RAW264.7 Cells Through NF-κB/MAPK Signaling Pathways

Nigella sativa is a valuable herb for its functional compositions in both food and medication. N. sativa seeds can enhance immunity, anti-inflammation and analgesia and hypoglycemia, but most of the related researches are related to volatile oil and extracts, and the activity and mechanism of compounds is not clear. In this study, Ethyl-α-D-galactopyranoside (EG), Methyl-α-D-glucoside (MG), 3-O-[β-D-xylopyranose-(1 → 3)-α-L-rhamnose-(1 → 2)-α-L-arabinose]-28-O-[α-L-rhamnose-(1 → 4)-β-D-glucopyranose-L-(1 → 6)-β-D-glucopyranose]-hederagenin (HXRARG) and 3-O-[β-D-xylopyranose-(1 → 3)-α-L-rhamnose-(1 → 2)-α-L-arabinose]-hederagenin (HXRA) were isolated and identified from N. sativa seeds. In addition, four compounds could activate NF-κB pathway by promoting the expression of phosphorylation of P65 and IκBα, promoting the phosphorylation of JNK, Erk and P38 to activate MAPK signaling pathway, enhancing the proliferation and phagocytic activity of RAW264.7 cells, and promoting the release of NO, TNF-α and IL-6 on RAW264.7 cell in vitro. The results showed that N. sativa can be used as dietary supplement to enhance immune.

Nigella sativa L. and COVID-19: A Glance at The Anti-COVID-19 Chemical Constituents, Clinical Trials, Inventions, and Patent Literature

COVID-19 has had an impact on human quality of life and economics. Scientists have been identifying remedies for its prevention and treatment from all possible sources, including plants. Nigella sativa L. (NS) is an important medicinal plant of Islamic value. This review highlights the anti-COVID-19 potential, clinical trials, inventions, and patent literature related to NS and its major chemical constituents, like thymoquinone. The literature was collected from different databases, including Pubmed, Espacenet, and Patentscope. The literature supports the efficacy of NS, NS oil (NSO), and its chemical constituents against COVID-19. The clinical data imply that NS and NSO can prevent and treat COVID-19 patients with a faster recovery rate. Several inventions comprising NS and NSO have been claimed in patent applications to prevent/treat COVID-19. The patent literature cites NS as an immunomodulator, antioxidant, anti-inflammatory, a source of anti-SARS-CoV-2 compounds, and a plant having protective effects on the lungs. The available facts indicate that NS, NSO, and its various compositions have all the attributes to be used as a promising remedy to prevent, manage, and treat COVID-19 among high-risk people as well as for the therapy of COVID-19 patients of all age groups as a monotherapy or a combination therapy. Many compositions of NS in combination with countless medicinal herbs and medicines are still unexplored. Accordingly, the authors foresee a bright scope in developing NS-based anti-COVID-19 composition for clinical use in the future.

The effect of Nigella sativa oil on vascular dysfunction assessed by flow-mediated dilation and vascular-related biomarkers in subject with cardiovascular disease risk factors: A randomized controlled trial

Cardiovascular diseases (CVD) are the leading causes of mortality worldwide. Flow-mediated dilation (FMD) is a marker of vascular function. Beneficial cardiometabolic effects of Nigella sativa (N. sativa) have been observed. We evaluated the effect of N. sativa oil on FMD, plasma nitrite, and nitrate (NOx) as nitric oxide (NO) metabolites, and inflammatory markers in subjects with CVD risk factors. Fifty participants were randomly assigned to either the N. sativa (two capsules of 500 mg N. sativa oil) or the placebo group (two capsules of 500 mg mineral oil), for 2 months. The brachial FMD, plasma NOx, vascular cellular adhesion molecule-1 (VCAM-1), and intracellular adhesion molecule-1 (ICAM-1) were measured. FMD and plasma NOx levels was significantly increased in the N. sativa group compared to the placebo group (changes: 2.97 ± 2.11% vs. 0.71 ± 3.19%, p < 0.001 for FMD and 4.73 ± 7.25 μmol/L vs. 0.99 ± 5.37 μmol/L, p = 0.036 for plasma NOx). However, there was no significant difference in ICAM-1 and VCAM-1 levels between groups. Therefore, N. sativa oil improves vascular NO and FMD in subjects with cardiovascular risk factors. However, more studies are warranted to confirm the beneficial impacts of the N. sativa oil on vascular inflammation.

Effect of Nigella sativa supplementation on kidney function, glycemic control, oxidative stress, inflammation, quality of life, and depression in diabetic hemodialysis patients: study protocol for a double-blind, randomized controlled trial

Background and objectives

The kidney is probably the most crucial target of microvascular damage in diabetes, which can ultimately eventuate end-stage renal disease (ESRD). Hemodialysis is the most usual way of renal replacement therapy in ESRD. Patients receiving hemodialysis are susceptible to many complications like hyperglycemia, inflammation, depression, anxiety, and poor quality of life. So, they are constrained to consume many drugs. Medicinal herbs are used in different cultures as a reliable source of natural remedies. This study aims to determine the efficacy of Nigella sativa (NS) oil supplementation on blood glucose, kidney function tests, inflammation, oxidative stress, quality of life, and depression in hemodialysis patients.

Methods and analysis

This double-blind, randomized controlled trial will enroll 46 patients with diabetes mellitus who give hemodialysis thrice a week. Patients who have an inflammatory or infectious disease and who are receiving nonsteroidal anti-inflammatory drugs will be excluded. Patients will be randomized to the treatment and control group, which will be recommended using two soft gels of NS and paraffin oil, respectively. Laboratory tests will be assessed at baseline and end of the study, including fasting blood sugar, glycated albumin, insulin, creatinine, blood urea nitrogen, urea, uric acid, superoxide dismutase, malondialdehyde, total antioxidant capacity, high sensitive C reactive protein, and 24-h urine volume. Also, the kidney disease and quality of life and hospital anxiety and depression scale questionnaires will be evaluated.

Discussion

Previous studies have reported a positive effect of Nigella sativa supplementation in chronic kidney disease, but there is no evidence that this plant is safe in hemodialysis patients. The results of this study can be helpful in better control of blood sugar and kidney function and reduce complications in diabetic hemodialysis patients.

Trial registration

Iranian Registry of Clinical Trials . Registered on 31 May 2020

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05917-y.

Anti-Inflammatory, Antimicrobial, and Vasoconstriction Activities of an Anti-Hemorrhoidal Mixture of Alchemilla vulgaris, Conyza bonariensis, and Nigella sativa: In Vitro and Clinical Evaluations

Nigella sativa, Conyza bonariensis, and Alchemilla vulgaris are highly recommended in Greco-Arab traditional medicine as anti-hemorrhoid medicinal plants. The efficacy and safety of a topical cream (HPC) consisting of water–ethanol extracts of these three plants were evaluated here in vitro and in a randomized, double-blind, placebo-controlled study (RDBPC). HPC showed no significant cytotoxic effects in fibroblast cell line 3T3 (LDH-release and MTT assay); it inhibited the nitric oxide production by cultured monocyte cell line THP-1 in a dose-dependent manner (reaching the control levels of untreated cells at a concentration of 100 μg/mL). HPC showed a dose-dependent antibacterial activity against Escherichia coli (60% inhibition compared to Ampicillin at 5 mg/disc) and a significant vasoconstriction effect on intestinal vein rings (40% increase compared to phenylephrine). In a RDBPC with 77 hemorrhoidal disease (patients ages 19–61 years with a median grade of hemorrhoids of 2.0), we determined the anti-hemorrhoid efficacy and safety of HPC. The patients were randomly assigned to the HPC group (54 patients) or the placebo group (23 patients). They were asked to apply 2–3 mL of HPC or placebo twice daily for 6 days. The degree of hemorrhoidal disease severity, hemorrhage severity, pain, and itching served as an evaluation of the HPC efficacy. Compared to the placebo group, the obtained results showed that 6 days of treatment with HPC reduced the indexes of hemorrhage severity, severity of pain, and severity of itching to 0–1, 1, and 1 after 6 days, respectively. In conclusion, patients treated with HPC had a significant clinical improvement in all disease severity parameters compared to placebo. In vitro evaluations proved HPC to have significant antimicrobial, anti-inflammatory, and vasoconstriction effects. Therefore, HPC represents an interesting alternative treatment for hemorrhoidal disease.

Antioxidant Properties of Ester Derivatives of Cinnamic and Hydroxycinnamic Acids in Nigella sativa and Extra-Virgin Olive Oils-Based Emulsions

New hydrophobic derivatives of cinnamic and hydroxycinnamic (ferulic and cumaric) acids obtained by chemical esterification of the carboxylic group with C10 linear alcohol were studied to evaluate their antioxidant capacity toward the superoxide anion and hydrogen peroxide in physiological buffer and in extra-virgin olive oil (EVO) or Nigella sativa oils. Results showed that cumaric and ferulic acids have higher antioxidants activity against superoxide anion and hydrogen peroxide than the other compounds. Cumaric acid and its C10-ester derivative were selected to be incorporated into EVO or Nigella sativa oil-based emulsions. The prepared emulsions had a comparable particle size distribution (in the range of 3–4 µm) and physical stability at least up to three months. Nigella sativa oil-based emulsions loaded with cumaric acid or its C10-ester showed a higher capacity to scavenger superoxide anion and hydrogen peroxide than EVO oil-based emulsions. In conclusion, cumaric acid or its C10-ester could promote the antioxidant properties of Nigella sativa oil when formulated as emulsions.