In Vivo Subacute Toxicity and Antidiabetic Effect of Aqueous Extract of Nigella sativa

Phytochemicals and their Potential Mechanisms against Insulin Resistance

Insulin's inception dates back to 1921 and was unveiled through a momentous revelation. Diabetes is a dangerous, long-term disease in which the body fails to generate enough insulin or utilize the insulin it creates adequately. This causes hyperglycemia, a state of high blood sugar levels, which can even put a person into a coma if not managed. Activation of the insulin receptor corresponds to two crucial metabolic functions, i.e., uptake of glucose and storage of glycogen. Type 2 diabetes mellitus (T2DM) exists as one of the most challenging medical conditions in the 21st century. The sedentary lifestyle and declining quality of food products have contributed to the rapid development of metabolic disorders. Hence, there is an urgent need to lay some reliable, significant molecules and modalities of treatment to combat and manage this epidemic. In this review, we have made an attempt to identify and enlist the major phytoconstituents along with the associated sources and existing mechanisms against insulin resistance. The conducted study may offer potential sustainable solutions for developing and formulating scientifically validated molecules and phytoconstituents as formulations for the management of this metabolic disorder.

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.

Co-administration of Pterocarpus marsupium Extract and Glibenclamide Exhibits Better Effects in Regulating Hyperglycemia and Associated Changes in Alloxan-induced Diabetic Mice

BACKGROUND

Diabetes mellitus (DM) is a well-known global metabolic disorder. For its treatment, glibenclamide (GLB) is very often prescribed. However, herbal drugs are considered effective and better alternatives due to their low risk of side effects. This study was conducted to determine the combined effects of GLB and Pterocarpus marsupium (PM, a commonly available Indian herb) extract for the effective and safe treatment of hyperglycemia in the mouse model.

METHODS

Healthy adult male mice were distributed into five groups (n=7 in each group). Group I acted as the control, whereas groups II, III, IV, and V were considered experimental groups which received a single dosage (150 mg/kg body weight) of alloxan (ALX) intraperitoneally (i.p.). In addition, groups III, IV, and V received a pre-standardized dose of GLB (500 μg/kg body weight), PM extract (150 mg/kg body weight), and GLB+PM, respectively, at the same doses as used in individual treatment, after the seventh day of ALX administration for 15 days and the alterations in different DM related parameters were evaluated.

RESULTS

ALX-induced hyperglycemia and other adverse effects were nearly normalized by GLB and PM co-treatment as evidenced by marked suppression in glucose, triglyceride, total-cholesterol, lipid-peroxidation, and lipid-hydroperoxides with an increase in antioxidants status and liver glycogen content. The positive effects were more pronounced when both GLB and PM were given, as compared to that of either of the drugs, administered alone. Liver ultra-structure, analyzed through histology and transmission electron microscopy revealed normalization of the ALX-induced damaged hepatocytes. The presence of epicatechin, the major phytoconstituent of the PM extract, as confirmed by high-performance liquid chromatography (HPLC), is responsible for its antioxidative and glucose-lowering activities.

CONCLUSION

These findings reveal that PM, along with GLB, exhibits synergistic and better effects than the individual drug in regulating hyperglycemia and associated changes in alloxan-induced mice.

Potential health benefits of Nigella sativa on diabetes mellitus and its complications: A review from laboratory studies to clinical trials

This review aims to gather and summarize up-to-date information on the potential health benefits of Nigella sativa (NS) on diabetes mellitus (DM) and its complications from different animal models, clinical trials and in vitro studies. DM is one of the most prevalent metabolic disorders resulting from chronic hyperglycaemia due to problems in insulin secretion, insulin action or both. It affects people regardless of age, gender and race. The main consequence of DM development is the metabolic dysregulation of glucose homeostasis. Current treatments for DM include pharmacological therapy, insulin and diabetic therapy targeting β cells. Some of these therapeutic approaches are promising; however, their safety and effectiveness remain elusive. Since ancient times, medicinal plants have been used and proven effective against diseases. These plants are believed to be effective and benefit physiological and pathological processes, as they can be used to prevent, reduce or treat multiple diseases. Nigella sativa Linn. is an annual indigenous herbaceous plant belonging to Ranunculaceae, the buttercup family. NS exhibits multifactorial activities; it could ameliorate oxidative, inflammatory, apoptotic and insulinotropic effects and inhibit carbohydrate digestive enzymes. Thus, this review demonstrates the therapeutic potential of NS that could be used as a complement or adjuvant for the management of DM and its complications. However, future research should be able to replicate and fill in the gaps of the study conducted to introduce NS safely to patients with DM.

Chemical Composition Related to Antimicrobial Activity of Moroccan Nigella sativa L. Extracts and Isolated Fractions

Background

Nigella sativa L. (NS) is an aromatic and medicinal plant commonly used in Mediterranean cuisine. Its grains contain a large amount of fixed oil and have many therapeutic virtues and medicinal properties (antioxidant, antidiabetic, antimicrobial, and anticancer).

Aim

The aim of this work is to study the antimicrobial activity of Nigella sativa L. extracts and separated fractions on various pathogenic strains and to correlate that with its chemical composition.

Methods

Extracts from Moroccan Nigella sativa seeds were extracted using successive organic solvents, and their hexane and acetone extracts were separated by column chromatography. The chemical composition of extracts, fractions, and essential oil was determined by GC-MS and HPLC-DAD. Extracts and fractions were evaluated for antimicrobial activity through disk diffusion against Gram-positive bacteria (Staphylococcus aureus, Bacillus cereus, and Listeria innocua), Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa), and yeast (Candida pelliculosa) for 1 mg/mL concentration. Bacterial strains were followed to study their behaviors over time in different concentrations. The minimum inhibitory concentration of Nigella sativa essential oil was determined against Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Candida albicans. Results and Conclusion. Although hexane extract was active against both types of bacteria (Gram+ and Gram−), some of its fractions were specifically active against only one type. Fraction (SH4) had the highest activity (15 mm inhibitory diameter). Acetone extract was nonactive but surprisingly resulted in specific active fractions, and the most interesting one was (SA7) that had an inhibitory diameter of 13 mm. This antibacterial effect was related to fatty acids (linoleic and palmitic acids) in (SH4) and 17 pentatriacontene in (SA7). Moreover, the antifungal activity of hexane fractions (10–13 mm) was higher than hexane extract (8 mm), but for acetone, it was the opposite. Acetone extract had a higher activity (18 mm) than its fractions (8–12 mm), except for (SA7) (19 mm). Those inhibitions were attributed to gallic acid, cysteine, and apigenin in acetone extract and cysteine with ascorbic acid in fraction (SA7). Antifungal activity of the essential oil was more pronounced than the antibacterial one. Indeed, determined MICs in the first case were on the microgram scale (MIC = 8 μg/mL, Candida albicans), while in the second case, they were on the milligram scale (MIC = 0.96 mg/mL for Staphylococcus aureus, 0.5 mg/mL for Bacillus cereus, and 0.68 mg/mL for Escherichia coli). This antifungal activity was attributed to three major compounds beta-cymene, alpha-thujene, origanene, and thymoquinone. Results of strains behavior over time at different concentrations of the fractions showed all the curves went through a maximum around 20 hours and had a delay of expression of 5 hours at the start. Taking all results into count, Nigella sativa L. extracts and/or derived principles could form promising antimicrobial agents for therapeutical and industrial uses.

Black Cumin (Nigella sativa L.): A Comprehensive Review on Phytochemistry, Health Benefits, Molecular Pharmacology, and Safety

Mounting evidence support the potential benefits of functional foods or nutraceuticals for human health and diseases. Black cumin (Nigella sativa L.), a highly valued nutraceutical herb with a wide array of health benefits, has attracted growing interest from health-conscious individuals, the scientific community, and pharmaceutical industries. The pleiotropic pharmacological effects of black cumin, and its main bioactive component thymoquinone (TQ), have been manifested by their ability to attenuate oxidative stress and inflammation, and to promote immunity, cell survival, and energy metabolism, which underlie diverse health benefits, including protection against metabolic, cardiovascular, digestive, hepatic, renal, respiratory, reproductive, and neurological disorders, cancer, and so on. Furthermore, black cumin acts as an antidote, mitigating various toxicities and drug-induced side effects. Despite significant advances in pharmacological benefits, this miracle herb and its active components are still far from their clinical application. This review begins with highlighting the research trends in black cumin and revisiting phytochemical profiles. Subsequently, pharmacological attributes and health benefits of black cumin and TQ are critically reviewed. We overview molecular pharmacology to gain insight into the underlying mechanism of health benefits. Issues related to pharmacokinetic herb-drug interactions, drug delivery, and safety are also addressed. Identifying knowledge gaps, our current effort will direct future research to advance potential applications of black cumin and TQ in health and diseases.

Hepatic adverse drug reactions in Malaysia: An 18-year review of the national centralized reporting system

PURPOSE

To determine the incidence, demographic profile, background of reporters, causative agents, severity and clinical outcomes of hepatic adverse drug reaction (ADR) reports in Malaysia using the national ADR reporting database.

METHODS

The ADR reports recorded between 2000 and 2017 were retrospectively analysed to identify hepatic ADR reports. The trend and characteristics of hepatic ADR cases were described. Multivariate disproportionality analysis of the causative agents was performed to generate signals of hepatic ADRs.

RESULTS

A total of 2090 hepatic ADRs (1.77% of all ADRs) were reported with mortality rate of 12.7% among cases with known clinical outcomes. The incidence of hepatic ADR reporting in Malaysia increased significantly over 18 years from 0.26 to 9.45 per million population (P < .001). Antituberculosis drugs (n = 268, 12.82%) was the most common suspected class of causative agents with a reporting odds ratio (ROR) and 95% CI of 8.39 (7.26-9.70), followed by traditional/complementary medicines or herbal/dietary supplements (TCM/HDS) (n = 235, 11.24%, ROR 3.26 [2.84-3.75]), systemic antibacterials (n = 159, 7.61%, ROR 2.65 [2.25-3.13]), lipid modifying agents (n = 142, 6.79%, ROR 2.21 [1.86-2.63]) and amiodarone (n = 137, 6.56%, ROR 35.25 [28.40-43.75]). Most (72.9%) of the TCM/HDS were not registered with the authorities.

CONCLUSIONS

Hepatic ADR cases have increased significantly in Malaysia, with antituberculosis drugs, systemic antibacterials, and TCM/HDS being the most common causative agents reported. Most TCM/HDS reported to be associated with hepatic ADR were not registered with the authorities.

Nigella sativa (black seed) safety: an overview

Nigella sativa (commonly known as black seed or black cumin), from the family Ranunculaceae, is a plant that grows in countries bordering the Mediterranean Sea. This narrative review discusses the toxicological profile reported by short- to long-term studies that examined different extracts and oils of N. sativa seeds. Scientific databases including Web of Science, PubMed, Scopus, and Google Scholar were searched using appropriate keywords. LD50 for administered N. sativa seed fixed oil varied from 28.8 mL/kg to 3,371 mg/kg in mice, while 21 g/kg of aqueous, methanol, and chloroform extracts of N. sativa did not lead to any mortality. Subacute toxicity evaluations indicated that aqueous, methanol, and chloroform extracts of N. sativa at doses as high as 6 g/kg do not produce toxicity. Investigation of chronic toxicity found that 2 mL/kg of N. sativa fixed oil is slightly toxic. Cytotoxicity studies indicated that N. sativa chloroform and petroleum ether extracts are more cytotoxic than its other extracts. Although studies that assessed N. sativa toxicity generally introduced it as a safe medicinal herb, to draw a more definitive conclusion on its safety, more detailed studies must be conducted.

Effect of Nigella sativa oil supplement on risk factors for cardiovascular diseases in patients with type 2 diabetes mellitus

This study aimed to evaluate the effects of Nigella sativa oil on serum level of systemic inflammation, oxidative stress, fasting blood glucose (FBG), and lipid profile in patients with type 2 diabetes mellitus (T2DM). This double-blind randomized clinical trial study was based on 50 patients with T2DM. Patients were allocated randomly to either N. sativa oil or placebo groups. The intervention group received 1,000 mg N. sativa oil as two capsules, daily for 8 weeks, whereas the placebo group received a corresponding placebo. At baseline and the end of the study, 5 ml blood was collected from each patient after 14-hour fasting for measuring serum C-reactive protein (hs-CRP), malondialdehyde (MDA), FBS, and lipid profile. Analyses covariance was performed to compare investigated parameters between two groups, controlled for relevant covariates. Using N. sativa supplement was significantly associated with decrease in FBS (p < .001), triglyceride (p < .001), total cholesterol (p < .001), low-density lipoprotein cholesterol (p < .001), serum hs-CRP, MDA (p < .001) and increase in serum level of high-density lipoprotein cholesterol (p < .001) in intervention group compared with placebo group. Nigella sativa oil supplement has cardiovascular protective effects in patients with T2DM, by improving the lipid profile and glycemia, by reducing the C-reactive protein level and the lipid peroxidation.

Nigella sativa L. (Black Cumin): A Promising Natural Remedy for Wide Range of Illnesses

The seed of Nigella sativa (N. sativa) has been used in different civilization around the world for centuries to treat various animal and human ailments. So far, numerous studies demonstrated the seed of Nigella sativa and its main active constituent, thymoquinone, to be medicinally very effective against various illnesses including different chronic illness: neurological and mental illness, cardiovascular disorders, cancer, diabetes, inflammatory conditions, and infertility as well as various infectious diseases due to bacterial, fungal, parasitic, and viral infections. In spite of limited studies conducted so far, the promising efficacy of N. sativa against HIV/AIDS can be explored as an alternative option for the treatment of this pandemic disease after substantiating its full therapeutic efficacy. Moreover, the strong antioxidant property of this valued seed has recently gained increasing attention with regard to its potential role as dietary supplement with minimal side effects. Besides, when combined with different conventional chemotherapeutic agents, it synergizes their effects resulting in reducing the dosage of concomitantly used drugs with optimized efficacy and least and/or no toxicity. A number of pharmaceutical and biological properties have been ascribed to seeds of N. sativa. The present review focuses on the profile of high-value components along with traditional medicinal and biological principles of N. sativa seed and its oil so as to explore functional food and nutraceutical potential of this valued herb.