Nigella sativa inhibits intestinal glucose absorption and improves glucose tolerance in rats

The effect of Nigella sativa supplementation on glycemic status in adults: An updated systematic review and meta-analysis of randomized controlled trials

This systematic review and meta-analysis of randomized controlled trials (RCTs) sought to evaluate the effects of Nigella sativa (N. sativa) consumption on glycemic index in adults. A systematic literature search up to December 2023 was completed in PubMed, Scopus, and Web of Science, to identify eligible RCTs. Random effects models were assessed based on the heterogeneity tests, and pooled data were determined as weighted mean differences with a 95 % confidence interval. Finally, a total of 30 studies were found to be eligible for this meta-analysis. The pooled results using random effects model indicated that N. sativa supplementation significantly reduced FBS (SMD: -1.71; 95 % CI: -2.11, -1.31, p <0.001; I2= 92.7 %, p-heterogeneity <0.001) and HA1c levels (SMD: -2.16; 95 % CI: -3.04, -1.29, p <0.001; I2= 95.7 %, p-heterogeneity <0.001) but not effect on insulin (SMD = 0.48; 95 % CI: -0.53, 1.48, P = 0.353; I2= 96.1 %, p-heterogeneity <0.001), and HOMA-IR (SMD: -0.56; 95 % CI: -1.47, 0.35, p=0.229; I2= 95.0 %, p-heterogeneity <0.001).Overall, the evidence supports the consumption of N. sativa to reduce FBS and HA1c levels. Additional research, featuring extended durations and robust study designs, is necessary to determine the ideal dosage and duration of N. sativa supplementation for achieving a positive impact on glycemic markers.

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.

Vasorelaxant effects of biochemical constituents of various medicinal plants and their benefits in diabetes

Endothelial function plays a pivotal role in cardiovascular health, and dysfunction in this context diminishes vasorelaxation concomitant with endothelial activity. The nitric oxide-cyclic guanosine monophosphate pathway, prostacyclin-cyclic adenosine monophosphate pathway, inhibition of phosphodiesterase, and the opening of potassium channels, coupled with the reduction of calcium levels in the cell, constitute critical mechanisms governing vasorelaxation. Cardiovascular disease stands as a significant contributor to morbidity and mortality among individuals with diabetes, with adults afflicted by diabetes exhibiting a heightened cardiovascular risk compared to their non-diabetic counterparts. A plethora of medicinal plants, characterized by potent pharmacological effects and minimal side effects, holds promise in addressing these concerns. In this review, we delineate various medicinal plants and their respective biochemical constituents, showcasing concurrent vasorelaxant and anti-diabetic activities.

The Effect of Therapeutic Doses of Culinary Spices in Metabolic Syndrome: A Randomized Controlled Trial

Non-communicable diseases (NCDs) place a significant burden on global health and the healthcare systems which support it. Metabolic syndrome is a major risk factor for a large number of NCDs; however, treatments remain limited. Previous research has shown the protective benefits of edible dietary spices on key components of metabolic syndrome. Therefore we performed a 12-week double-blind, placebo-controlled, randomized, clinical trial to evaluate the effect of ginger (Zingiber officinale), cinnamon (Cinnamomum), and black seed (Nigella sativa) consumption on blood glucose, lipid profiles, and body composition in 120 participants with, or at risk of, metabolic syndrome. Each participant consumed 3 g/day of powder (spice or placebo). Data related to different parameters were collected from participants at the baseline, midpoint, and endpoint of the intervention. Over the 12-week interventions, there was an improvement in a number of biochemical indices of metabolic syndrome, including fasting blood glucose, HbA1c, LCL, and total cholesterol associated with supplementation with the spices when compared to a placebo. This study provides evidence to support the adjunct use of supplementation for those at risk of metabolic syndrome and its sequelae.

Sublingual Administration of Teucrium Polium-Loaded Nanofibers with Ultra-Fast Release in the Treatment of Diabetes Mellitus: In Vitro and In Vivo Evaluation

In this study, Teucrium polium (TP) methanolic extract, which has antidiabetic activity and protects the β-cells of the pancreas, was loaded in polyethylene oxide/sodium alginate nanofibers by electrospinning and administered sublingually to evaluate their effectiveness in type-2 diabetes mellitus (T2DM) by cell culture and in vivo studies. The gene expressions of insulin, glucokinase, GLUT-1, and GLUT-2 improved in TP-loaded nanofibers (TPF) on human beta cells 1.1B4 and rat beta cells BRIN-BD11. Fast-dissolving (<120 s) sublingual TPF exhibited better sustainable anti-diabetic activity than the suspension form, even in the twenty times lower dosage in streptozotocin/nicotinamide-induced T2DM rats. The levels of GLP-1, GLUT-2, SGLT-2, PPAR-γ, insulin, and tumor necrosis factor-alpha were improved. TP and TPF treatments ameliorated morphological changes in the liver, pancreas, and kidney. The fiber diameter increased, tensile strength decreased, and the working temperature range enlarged by loading TP in fibers. Thus, TPF has proven to be a novel supportive treatment approach for T2DM with the features of being non-toxic, easy to use, and effective.

The Use of Nigella sativa in Cardiometabolic Diseases

Nigella sativa L. is an herb that is commonly used in cooking and in traditional medicine, particularly in Arab countries, the Indian subcontinent, and some areas of eastern Europe. Nigella sativa is also called "black cumin" or "black seeds", as the seeds are the most-used part of the plant. They contain the main bioactive component thymoquinone (TQ), which is responsible for the pleiotropic pharmacological properties of the seeds, including anti-oxidant, anti-inflammatory, anti-hypertensive, anti-hepatotoxic, hypoglycemic, and lipid-lowering properties. In this narrative review, both the potential mechanisms of action of Nigella sativa and the fundamental role played by pharmaceutical technology in optimizing preparations based on this herb in terms of yield, quality, and effectiveness have been outlined. Moreover, an analysis of the market of products containing Nigella sativa was carried out based on the current literature with an international perspective, along with a specific focus on Italy.

Traditional Herbal Medications Utilized in the Indian Medical System forthe Management of Diabetes: An Updated Review and Clinical Implications

Phytomedicine, also called botanical medicine, is the practice of using plants to treat disease. Diabetes, for example, has been treated and prevented with herbal medication for a lot longer than Western medicine. Worldwide, diabetes has become a major health concern. The management of diabetes and hyperglycemia, two of the most common public health threats, is far from ideal. When hyperglycemia persists or is not under control, diabetes-related complications, like blindness, lower limb amputations, renal disease, and cardiovascular disease, play a significant role in the morbidity and mortality of the disease. Although chemicals and biochemical agents can assist in managing diabetes, there is currently no complete cure for the disease. Herbal remedies are one of many methods that can be used to treat and prevent diabetes and its subsequent problems. Numerous traditional treatments have been discovered for diabetes as a result of extensive research efforts. However, there are many factors to consider when deciding which herbs to use, such as the patient's financial status, the presence or absence of co-morbidities, and the accessibility, cost-effectiveness, and safety profile of the herbs. This article focuses on the use of herbal and natural remedies in the treatment and prevention of diabetes, the mechanisms by which these remedies lower blood glucose levels, and the specific herbal items now utilized in the management of diabetes.

Potential Pharmacological Applications of Nigella Seeds with a Focus on Nigella sativa and Its Constituents against Chronic Inflammatory Diseases: Progress and Future Opportunities

The leading cause of death worldwide has been identified as chronic illnesses, according to the World Health Organization (WHO). Chronic inflammatory conditions such as asthma, cancer, diabetes, heart disease, and obesity account for three out of every five deaths. Although many people benefit from using nonsteroidal anti-inflammatory medicines (NSAIDs) for pain and inflammation relief, there are significant adverse effects to using these medications. Medicinal plants possess anti-inflammatory properties with minimal or no side effects. Nigella sativa (NS), also known as black cumin, is one of the plants used in traditional medicine the most. Many studies on the NS have shown that their therapeutic properties are attributed to the seed, oil, and secondary metabolites. This plant has been studied extensively and has many medical uses, such as anti-inflammatory. NS or its phytochemical compounds, such as thymoquinone, can cause cell apoptosis via oxidative stress, block efflux pumps, enhance membrane permeability, and exert potent biocidal effects. Notwithstanding the extensively documented anti-inflammatory effectiveness observed in the experimental model, the precise mechanisms underlying its anti-inflammatory effects in diverse chronic inflammatory diseases and its multi-targeting characteristics remain largely unexplored. This review examines NS or its secondary metabolites, a valuable source for the therapeutic development of chronic inflammatory diseases. Most clinical studies were done for diabetes and cardiovascular disease; therefore, more studies are required to examine the NS extracts and phytoconstituents to treat cancer, obesity, diabetes, asthma, neurological disorders, and COVID-19. This study will be a significant resource for clinicians and biologists seeking a pharmaceutical solution for inflammatory diseases.

Recent Progress on Microtubule Degradation Agents

Targeted protein degradation (TPD) has emerged as the most promising approach for the specific knockdown of disease-associated proteins and is achieved by exploiting the cellular quality control machinery. TPD technologies are highly advantageous in overcoming drug resistance as they degrade the whole target protein. Microtubules play important roles in many cellular processes and are among the oldest and most well-established targets for tumor chemotherapy. However, the development of drug resistance, risk of hypersensitivity reactions, and intolerable toxicities severely restrict the clinical applications of microtubule-targeting agents (MTAs). Microtubule degradation agents (MDgAs) operate via completely different mechanisms compared with traditional MTAs and are capable of overcoming drug resistance. The emergence of MDgAs has expanded the scope of TPD and provided new avenues for the discovery of tubulin-targeted drugs. Herein, we summarized the development of MDgAs, and discussed their degradation mechanisms, mechanisms of action on the binding sites, potential opportunities, and challenges.

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.

A Review of the Potential Health Benefits of Nigella sativa on Obesity and Its Associated Complications

Obesity has become a worldwide epidemic and its prevalence continues to increase at an alarming rate. It is considered a major risk factor for the development of several comorbidities, including type 2 diabetes, stroke, other cardiovascular diseases and even cancer. Conventional treatments for obesity, such as dietary interventions, exercise and pharmacotherapy, have proven to have limited effectiveness and are often associated with undesirable side effects. Therefore, there is a growing interest in exploring alternative therapeutic approaches. Nigella sativa (NS), a medicinal plant with multiple pharmacological properties, has gained attention due to its potential role in the treatment of obesity and its associated complications. The aim of this review is therefore to assess the effects of NS on obesity and its complications and to provide insights into the underlying mechanisms. From this review, NS appears to play a complementary or supportive role in the treatment of obesity and its complications. However, future studies are needed to verify the efficacy of NS in the treatment of obesity and its complications and to prove its safety so that it can be introduced in patients with obesity.

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.

The Effectiveness of Nigella sativa and Ginger as Appetite Suppressants: An Experimental Study on Healthy Wistar Rats

Background

Obesity is a global pandemic that is associated with high morbidity and mortality. Natural herbs are commonly used for weight reduction and appetite suppression. Therefore, we aim to investigate the role and mechanism of Nigella sativa (NS) and ginger on weight reduction and appetite regulation.

Methods

This experimental study was performed at Imam Abdulrahman Bin Faisal University. Twenty-five female rats were distributed into 5 groups: NS (oral 1000mg/kg), Ginger (500 mg/kg), NS-ginger (both interventions), a positive control (intraperitoneal 50 μg/kg Liraglutide), and a negative control. Each intervention was given for 9 weeks. Food intake and body weight were assessed weekly. Serum lipid profile and peptides involved in appetite control (cholecystokinin (CCK), glucagon-like peptide 1(GLP-1), gastric inhibitory polypeptide (GIP), ghrelin, peptide YY, and orexin) were assayed at the end of the experiment.

Results

None of the interventions showed a statistically significant difference regarding food consumption or weight gain (p > 0.05). However, the three interventions significantly reduced total cholesterol (TC), NS and NS-ginger significantly increased HDL, NS increased ghrelin and ginger increased orexin.

Conclusion

The present dose and duration of NS, ginger, or in combination did not demonstrate a significant change in body weight or food consumption in comparison to the negative or positive controls. However, NS or ginger has improved the lipid profile by reducing TC and increasing HDL. In addition, NS or ginger can influence some of the peptides involved in appetite regulation such as the increase in ghrelin induced by NS and the reduction of orexin induced by ginger. We believe that these latter effects are novel and might indicate a promising effect of these natural products on appetite regulation.

Biological Properties, Phenolic Profile, and Botanical Aspect of Nigella sativa L. and Nigella damascena L. Seeds: A Comparative Study

The use of Nigella seeds in the food, pharmaceutical, and cosmetic fields is common, since the iniquity and the virtues of these plants are directly related to their characteristic phytochemical composition. This investigation focused on the comparative study of the botanical aspect, phenolic profile, and in vitro and in vivo biological activities of Nigella sativa L. (NS) and Nigella damascena L. (ND) seeds. The macro- and micro-morphological properties of these seeds were studied, and the key dissimilarities between them were clearly illustrated. The phytochemical contents and phenolic profiles were determined, and the in vitro antioxidant activity was assessed using four methods. The in vivo antioxidant and biochemical parameters of the blood of supplemented mice were determined. The results of the macro- and micro-structure analysis revealed differences between the two plants. Here, ND is characterized by higher phytochemical contents and the best antioxidant activities. The HPLC analysis indicated the presence of nine compounds, namely seven phenolic acids, particularly hydroxybenzoic and caffeic acids, and two flavonoids. The administration of ND extract to mice for 21 days at a concentration of 500 mg/kg allowed a substantial amelioration of plasma antioxidant properties. In addition, the extracts ameliorate blood parameters (cholesterol, triglycerides, glycemia, and urea). Furthermore, the antimicrobial activity of extracts demonstrated their effects on Staphylococcus and Aspergillus. Nigella seeds, in particular ND, expressed considerable in vitro antioxidant properties and demonstrated significant amelioration of mice blood properties. Consequently, these species can serve as a valuable source of compounds with various applications.

Effect of Nigella Sativa in Improving Blood Glucose Level in T2DM: Systematic Literature Review of Randomized Control Trials

BACKGROUND

Diabetes mellitus is a highly prevalent condition that affects people of all ages, races, and genders. Medicinal herbs have received a lot of attention from researchers, and they have suggested it to be a good adjuvant to oral diabetes medications because of their combined effects.

OBJECTIVES

The purpose of this systematic review is to summarize the available evidences and literature of Randomized Control Trials (RCTs) on Nigella sativa (NS) in the management of Type 2 Diabetes Mellitus (T2DM).

METHODS

A computerised database search was performed to obtain the relevant clinical trial studies. We searched the following PubMed and Google Scholar databases. Randomized controlled trials (RCTs) comparing NS versus any treatment for the management of T2DM in adults were eligible for inclusion.

RESULTS

A total of 7 articles were retrieved for interpretation, complete assessment and data extraction in this systematic review. This systematic review seeks to give thorough information on the effects of NS on glucose and insulin profile status in patients with T2DM.

INTERPRETATION & CONCLUSION

Different mechanisms are proposed which contribute to the anti-diabetic activity of NS. Various outcome parameters evaluated demonstrate a significant improvement in the management of T2DM and its complications upon intervention with NS.

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.

Anti-diabetic Potential of some Spices Commonly used in Diet with other Pharmacological Activities: A Review

Background::

Diabetes mellitus is a chronic metabolic disorder, the prevalence of which is increasing alarmingly throughout the world and imposes a serious impact on the health of the population as well as national economies. Effective management and primary prevention are essential to decrease the burden of diabetes faced by all nations. Although different therapies are available for diabetes, no known therapy can completely cure the disease, and many of them have a number of side effects with other limitations like long-term treatment, expensiveness, and less availability. Hence, the present review has given an emphasis on common dietary materials to find out a readily available source of anti-diabetic agents.

Objective:

The purpose of this work is to explore the anti-diabetic properties of certain spices which are most frequently used in Bangladesh and reported for their use in traditional treatment of diabetes and/or investigated scientifically for anti-diabetic activity.

Methods:

Two electronic databases, namely Pub Med and Google Scholar, were used for conducting a comprehensive search to collect information and data.

Results:

In this review, a total of 10 spices have been compiled with a brief description of their origin, part used, chemical constituents, mechanism of action, methods of experiment, model animals, and reported beneficial effects in diabetes with other pharmacological activities.

Conclusion:

The observed results of this study indicate the possibility of developing a therapeutic strategy called alternative and complementary medicine for the management of diabetes. The results also provide a starting point for researchers working with bioactive dietary plants with anti-diabetic potential.

Nigella sativa supplementation improves cardiometabolic indicators in population with prediabetes and type 2 diabetes mellitus: A systematic review and meta-analysis of randomized controlled trials

Objective

Nigella sativa (N. sativa) from the family Ranunculaceae has medicinal properties. Previous studies have reported promising findings showing that N. sativa may benefit cardiometabolic health; however, current evidence on its cardiometabolic effects on those with prediabetes and type 2 diabetes mellitus (T2DM) is still unclear. Hence, we conducted a systematic review and meta-analysis to assess the efficacy of N. sativa on cardiometabolic parameters in population with prediabetes and T2DM.

Methods

PubMed/Medline, ISI Web of Science, Scopus, and Cochrane library were systematically searched up to June 20, 2022. Meta-analyses using random-effects models were used.

Results

Eleven randomized controlled trials (RCTs) were included in the meta-analysis. N. sativa intervention resulted in significant changes in fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), c-reactive protein (CRP), and malondialdehyde (MDA), without overall changes in glucose levels after oral glucose tolerance test (OGTT), fasting insulin, homeostatic model assessment of insulin resistance (HOMA-IR), triglyceride, high-density lipoprotein cholesterol (HDL-C), and body mass index (BMI) when compared with the control group. In subgroup analyses, N. sativa supplementation enhanced serum levels of HDL-C in subjects with baseline HDL-C lower than 40 mg/dL. Furthermore, HOMA-IR and BMI values decreased in the N. sativa-supplemented group compared with the control group, when the length of follow-up was more than 8 weeks and the dose was more than 1 g/day for N. sativa supplementation, respectively.

Conclusion

Our findings indicate that N. sativa supplementation may effectively improve cardiometabolic profiles in individuals with prediabetes and T2DM.

The effect of nigella supplementation on blood pressure: A systematic review and dose-response meta-analysis

This study was performed to assess the effect of nigella supplementation on blood pressure levels among the adult population. A comprehensive search was carried out through PubMed, Scopus, Web of Science, and Cochrane Library by using relevant keywords to find out the randomized clinical trials evaluating the effect of nigella administration on systolic blood pressure (SBP) and diastolic blood pressure (DBP). A random-effect model was applied to achieve the overall effect size. Subgroup analysis and meta-regression were used to explore the source of heterogeneity and the effects of the possible moderators. Of the twenty-two trials that were eligible for the present study, seventeen studies consisting of 1048 participants were included in the meta-analysis. The results indicated that nigella administration could significantly reduce both SBP (-4.58 mmHg; 95%CI: -6.22, -2.94) and DBP (-3.08 mmHg; 95%CI: -4.62, -1.55). Subgroup analysis did not show any superiority between subgroups of variables. Dose-response analysis detected a nonlinear association between dose and duration of administration and change in blood pressure outcomes, highlighting that maximum SBP and DBP reduction was experienced at 2000 mg/day and 8 weeks of nigella administration, respectively. The present study suggests that nigella supplementation can be beneficial for managing blood pressure.

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

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

The protective effect of Nigella sativa seeds against monosodium glutamate-induced hepatic dysfunction in rats

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MSG-challenged rats were characterized by hepatic dysfunction and redox imbalance along with increased programmed cell death.

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The negative consequences of MSG consumption have been partially overcome by the nutritional inclusion of NSS.

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NSS restores the redox potential and ameliorates the histopathological deteriorations and apoptosis in the liver.

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These outcomes are of major importance in paving the road towards the incorporation of NSS as a candidate strategy against MSG-related abnormalities.

Monosodium glutamate (MSG) is one of the most commonly used feed additives which poses a threat to public health. Nigella sativa is a promising natural approach in this issue due to its antioxidant, hypolipidemic, and cytoprotective characters. Here, we investigated the potential protective effect of Nigella sativa seed (NSS) against MSG-induced hepatotoxicity in rats. To accomplish this objective, fifteen adult Wistar albino rats were randomly and equally divided into three groups for 21 days: the control group received no treatment, MSG group supplemented with MSG at a dose of 30 g/kg feed, and MSG + NSS group supplemented with MSG at the same previous dose together with NSS at a dose of 30 g/kg feed. NSS succeeded in boosting serum alkaline phosphatase activity and total cholesterol, triglycerides, and glucose levels. It reduced lipid peroxides in the serum and down-regulated glutathione reductase and superoxide dismutase 2 immuno-expression in the hepatic cells. NSS intervention provided cytoprotection by improving the histo-architecture of the liver and reducing the number of apoptotic cells. NSS was effective in protecting against the hepatotoxicity of MSG through its antioxidant and anti-apoptotic effects. These findings are of utmost significance in directing the attention towards the incorporation of NSS in our food industry as well as a health remedy in traditional medicine to fight MSG-related hepatic abnormalities.

An Overview on the Therapeutic Function of Foods Enriched with Plant Sterols in Diabetes Management

Diabetes is one of the most significant health issues across the world. People identified with diabetes are more vulnerable to various infections and are at a greater risk of developing cardiovascular diseases. The plant-based food we consume often contains many sterol-based bioactive compounds. It is well documented that these compounds could effectively manage the processes of insulin metabolism and cholesterol regulation. Insulin resistance followed by hyperglycemia often results in oxidative stress level enhancement and increased reactive oxygen species production. At the molecular level, these changes induce apoptosis in pancreatic cells and hence lead to insulin insufficiency. Studies have proved that plant sterols can lower inflammatory and oxidative stress damage connected with DNA repair mechanisms. The effective forms of phyto compounds are polyphenols, terpenoids, and thiols abundant in vegetables, fruits, nuts, and seeds. The available conventional drug-based therapies for the prevention and management of diabetes are time-consuming, costly, and with life-threatening side effects. Thereby, the therapeutic management of diabetes with plant sterols available in our daily diet is highly welcome as there are no side effects. This review intends to offer an overview of the present scenario of the anti-diabetic compounds from food ingredients towards the therapeutic beneficial against diabetes.

Antihyperglycemic Effect of Lavandula pedunculata: In Vivo, In Vitro and Ex Vivo Approaches

Lavandula pedunculata (Mill.) Cav. (LP) is one of lavender species traditionally used in Morocco to prevent or cure diabetes, alone or in the form of polyherbal preparations (PHP). Therefore, the primary objective of this study was to test the antihyperglycemic effect of the aqueous extract of LP, alone and in combination with Punica granatum L. (PG) and Trigonella foenum-graecum L. (FGK). The secondary objective was to explore some mechanisms of action on the digestive functions. The antihyperglycemic effect of the aqueous extract of LP, alone and in combination with PG and FGK, was studied in vivo using an oral glucose tolerance test (OGTT). In addition, LP extract was tested on the activities of some digestive enzymes (pancreatic α-amylase and intestinal α-glucosidase) in vitro and on the intestinal absorption of glucose ex vivo using a short-circuit current (I_sc) technique. Acute and chronic oral administration of LP aqueous extract reduced the peak of the glucose concentration (30 min, p < 0.01) and the area under the curve (AUC, p < 0.01). The effect of LP + PG was at the same amplitude to that of the positive control Metformin (MET). LP aqueous extract inhibited the pancreatic α-amylase with an IC₅₀ almost identical to acarbose (0.44 ± 0.05 mg/mL and 0.36 ± 0.02 mg/mL, respectively), as well as the intestinal α-glucosidase, (IC₅₀ = 131 ± 20 µg/mL) and the intestinal glucose absorption (IC₅₀ = 81.28 ± 4.01 µg/mL) in concentration-dependent manners. LP aqueous extract exhibited potent actions on hyperglycemia, with an inhibition on digestive enzymes and glucose absorption. In addition, the combination with PG and FGK enhanced oral glucose tolerance in rats. These findings back up the traditional use of LP in type 2 diabetes treatment and the effectiveness of the alternative and combinative poly-phytotherapy (ACPP).

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

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

Therapeutic Screening of Herbal Remedies for the Management of Diabetes

The study of diabetes mellitus (DM) patterns illustrates increasingly important facts. Most importantly, they include oxidative stress, inflammation, and cellular death. Up to now, there is a shortage of drug therapies for DM, and the discovery and the development of novel therapeutics for this disease are crucial. Medicinal plants are being used more and more as an alternative and natural cure for the disease. Consequently, the objective of this review was to examine the latest results on the effectiveness and protection of natural plants in the management of DM as adjuvant drugs for diabetes and its complex concomitant diseases.

Antidiabetic Activity of Nigella Sativa (Black Seeds) and Its Active Constituent (Thymoquinone): A Review of Human and Experimental Animal Studies

The use of herbal medicine to manage chronic conditions including diabetes has become a recent global trend. Diabetes mellitus (DM) is a group of metabolic disorders characterized by hyperglycemia. The present review is aimed to analyze the antidiabetic activity of N. sativa as many type 2 diabetic patients use it as a complementary therapy along with their modern allopathic medications or as an alternative therapy. The literature was reviewed in databases like Medline/PubMed Central/PubMed, Google Scholar, Science Direct, EBSCO, Scopus, Web of science, EMBASE, Directory of open access journals (DOAJ), and reference lists to identify relevant articles supporting the use of N. sativa in diabetes management. Numerous clinical and animal studies have demonstrated the antidiabetic efficacy of black seeds (N. sativa) and its major bioactive constituent thymoquinone. Based on these findings patients with diabetes may use N. sativa as an adjuvant therapy, which may help to reduce the dose and incidence of adverse effects of modern antidiabetic medicines.

Chemical Composition Analysis Using HPLC-UV/GC-MS and Inhibitory Activity of Different Nigella sativa Fractions on Pancreatic α-Amylase and Intestinal Glucose Absorption

Nigella sativa (NS) is a well-known plant for its various benefits and multiuse in traditional medicine. This study is aimed at investigating the chemical composition of the different NS fractions by using GC-MS for the esterified fatty acids or HPLC-UV for organic fraction and at evaluating the inhibitory effect on pancreatic α-amylase (in vitro, in vivo) and intestinal glucose absorption. Among all the investigated fractions, it was shown that they are rich with different molecules of great interest. The n-hexane fraction was characterized by the presence of linoleic acid (44.65%), palmitic acid (16.32%), stearic acid (14.60%), and thymoquinone (8.7%), while among the identified peaks in EtOH fraction we found catechin (89.03 mg/100 g DW), rutin (6.46 mg/100 g DW), and kaempferol (0.032 mg/100 g DW). The MeOH fraction was distinguished with the presence of gallic acid (19.91 mg/100 g DW), catechin (13.79 mg/100 g DW), and rutin (21.07 mg/100 g DW). Finally, the aqueous fraction was marked by the existence of different molecules; among them, we mention salicylic acid (32.26 mg/100 g DW), rutin (21.46 mg/100 g DW), and vanillic acid (3.81 mg/100 g DW). Concerning the inhibitory effect on pancreatic α-amylase, it was found that in the in vitro study, the best IC₅₀ registered were those of EtOH (0.25 mg/ml), MeOH (0.10 mg/ml), aqueous (0.031 mg/ml), and n-hexane fraction (0.76 mg/ml), while in the in vivo study an important inhibition of α-amylase in normal and diabetic rats was observed. Finally, the percentage of intestinal glucose absorption was evaluated for all tested extracts and it was ranging from 24.82 to 60.12%. The results of the present study showed that the NS seed fractions exert an interesting inhibitory effect of α-amylase and intestinal glucose absorption activity which could be associated with the existent bioactive compounds. Indeed, these compounds can be used as antidiabetic agents because of their nontoxic effect and high efficacy.

Effect of Nigella sativa oil extract on cardiometabolic risk factors in type 2 diabetes: A randomized, double-blind, placebo-controlled clinical trial

The objective of this study was to determine the effects of Nigella sativa oil extract on cardiometabolic risk factors in people with type 2 diabetes (T2D). A randomized, controlled, clinical trial was conducted on 43 patients with T2D (23 women and 20 men; aged 53.5 ± 7.4 years). The intervention group (N = 23) received two 500-mg per day soft gel capsules containing Nigella sativa oil extract and the control group (N = 20) received two identical placebo soft gel capsules containing sunflower oil per day for the same period, 8 weeks. Pre- and post-intervention cardiometabolic risk factors were measured. Compared with the placebo, the N. sativa oil significantly decreased FBS (p = .03(, HbA1c (p = .001), total cholesterol (p = .04), TG (p = .003), LDL-c (p = .001), BMI (p < .001), waist circumference (p < .001), SBP (p = .001), and DBP (p = .002). HOMA-IR (p = .51) and HDL-c (p = .91) did not change significantly following Nigella sativa supplementation. Nigella sativa oil exerted beneficial effects on glycemic control, serum lipid profile, blood pressure, and body weight among people with T2D. Further long-term trials in the future may help confirm the current therapeutic benefits of Nigella sativa in T2D.

Ethnobotanical Survey of Medicinal Plants Used by Traditional Healers to Treat Diabetes in the Taza Region of Morocco

Type 2 diabetes is one of the noncommunicable diseases that is becoming a pandemic in Africa. In Morocco, traditional healers have started to use herbal medicines for the treatment of diabetes either individually or in combination with food. The current study aimed to perform an ethnobiological survey of antidiabetic plants use in the Taza region of Morocco. A total of 193 traditional healers were interviewed using a semistructured questionnaire. Data collected were analyzed utilizing the use value (UV), fidelity level (FL), and relative frequency citation (RFC) indices. Forty-six plant species belonging to 28 families were recorded for the treatment of diabetes in the Taza region of Morocco. The most frequently cited plant species are Salvia officinalis, Marrubium vulgare, and Ajuga iva. Lamiaceae, Asteraceae, and Fabaceae were the most reported families. Leaves are the most used part of plants to prepare drugs, the decoction is the preferred mode of preparation, and remedies are often administered orally. Interestingly, Cytisus battandieri, Urginea maritima, Plantago ovata, and Ziziphus jujuba were reported as new medicinal plants used to treat diabetes in the Taza region of Morocco. People in the Taza region still rely on indigenous plants for their basic healthcare needs. Further research should be carried out to validate the antidiabetic effect of the newly reported plant species. This validation can be investigated by the determination of bioactive compounds and evaluation of their in vitro and in vivo antidiabetic effects.

Effects of Nigella sativa oil supplementation on selected metabolic parameters and anthropometric indices in patients with coronary artery disease: A randomized, double-blind, placebo-controlled clinical trial

Various metabolic parameters are risk factors related to the amplified risk of atherosclerotic cardiovascular disease. A wide variety of data exist on Nigella sativa (NS) and metabolic parameters. The current study is designed to examine NS supplementation on lipid profile, blood pressure, glycemic control, anthropometric indices, and insulin resistance in individuals with coronary artery disease (CAD). In a randomized, double-blind, placebo-controlled clinical trial, 60 patients with CAD received either 2 g of NS oil or sunflower oil as a placebo for 8 weeks. Biochemical and anthropometric measurements were assessed. NS significantly reduced weight (-1.82 Kg; 95% C, [2.72, 4.13]), body mass index (-0.67 kg/m² ; 95% C, [0.33, 1.01]), waist circumference (-2.15 cm; 95% C, [1.06, 3.23]), hip circumference (-1.26 cm; 95% C, [0.61, 1.910]), waist-to-hip ratio (0.008; 95%C, [0.001, 0.01]), systolic (-9.52 mmHg; 95% C, [7.14, 11.9]), diastolic blood pressure (-8.26 mmHg; 95% C, [4.89, 11.62]), and fasting blood glucose (FBS) (-4.32 mg/dl; 95% C, [-0.51, 9.15]) as compared with the placebo group. The results indicate a potential beneficiary effect of NS on the metabolic parameters in CAD patients including improvements in anthropometric indices, blood pressure, and FBS.

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

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

Effect of Nigella sativa in the treatment of nonalcoholic fatty liver disease: A systematic review and meta-analysis of randomized controlled trials

The effectiveness of Nigella sativa (NS) treatment for nonalcoholic fatty liver disease (NAFLD) remains controversial. This systematic review, and meta-analysis, was conducted to evaluate potential benefits of NS for NAFLD. Up to June 11, 2020, randomized controlled trials (RCTs) evaluating NS for the treatment of NAFLD were searched and included from PubMed, Embase, Cochrane Library, and Web of science. Mean differences (MD) or risk ratio (RR) and 95% confidence intervals (CI) were calculated. Six articles from five trails with a total of 358 participants were included. Although NS has no beneficial effect on the levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL), triglyceride (TG), insulin, and tumor necrosis factor α (TNF-α), its supplementation did improve the levels of alanine transaminase (ALT), aspartate transaminase (AST), fasting blood sugar (FBS), high-density lipoprotein cholesterol (HDL), high-sensitivity C reactive protein (hs-CRP), and grade of fatty liver compared with placebo. In summary, this study showed that NS supplementation was effective in the treatment of NAFLD and could improve the levels of ALT, AST, FBS, HDL, and hs-CRP in patients with NAFLD, as well as the severity of NAFLD. High-quality large sample RCTs are necessary to confirm the benefit of NS supplementation for NAFLD.

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

BACKGROUND

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

OBJECTIVE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

The Effect of Hydro-Alcoholic Extract of Nigella sativa on Bmp7 and Bmp8b Expression in Rats Fed with a High-Fat Diet

Background: Bone morphogenetic protein7 (BMP7) and bone morphogenetic protein 8b (BMP8b) can induce browning of white adipose tissue. Objectives: The present study aimed to investigate the antioxidative effects of hydro-alcoholic extract of Nigella sativa on the repair of oxidative damage caused by a high-fat diet. Also, Bmp7 and Bmp8b gene expressions were investigated on white adipose tissue of the rats and then compared with metformin effects. Methods: Eighty rats were divided into two groups of prevention and treatment; then each set was divided into four sub-groups based on the administered diet (i.e., ordinary, fat, metformin, and extract of Nigella sativa). Lipid profile, paraoxonase1, malondialdehyde (MDA), HDL, and antioxidant capacity were measured in serum samples, and relative Bmp7 and Bmp8b gene expressions were calculated in white adipose tissue. Results: For both prevention and treatment sets, the weight of rats who received a high-fat diet decreased more compared to those in the normal diet group. The weight of rats who received metformin or nigella extract was also decreased compared to the high-fat diet group. MDA was also increased, but total antioxidant capacity and catalase were decreased in rats of the high-fat diet group compared to the normal diet group. MDA was also declined in nigella receiving rats, but liver PON1 activity, total antioxidant capacity, and catalase were increased, compared to the second group (P < 0.05). In the prevention and treatment set, Bmp8b gene expression was increased in the metformin and Nigella sativa groups, whereas it was decreased among those who received a high-fat diet. Bmp7 gene expression was decreased in the high-fat diet set, but metformin and Nigella sativa extract didn’t influence Bmp7 gene expression. Conclusions: This study demonstrated that Nigella sativa extract has a protective role against oxidative stress in a high-fat diet.

A comprehensive insight into potential roles of Nigella sativa on diseases by targeting AMP-activated protein kinase: a review

OBJECTIVES

Nigella sativa (NS) is a known medicinal herb with numerous therapeutic effects such as antidiabetic, anti-proliferative, anti-inflammatory, and anti-cancer activities. It has been indicated that NS can regulate cellular metabolism by adjusting transduction signaling pathways. Adenosine monophosphate-activated protein kinase (AMPK) is one of the main physiological processes, such as energy hemostasis, cellular metabolism, and autophagy regulators. Herb-derived medicines have always been considered as one of the main AMPK activators, and surprisingly recent data has demonstrated that it can be a target for NS and its derivatives.

EVIDENCE ACQUISITION

The literature search was conducted in PubMed, SCOPUS, Embase, ProQuest, and Google Scholar electronic resources. Published articles up to September 2020 were considered, and those of which investigated Nigella sativa effects on the AMPK pathway after meeting the inclusion criteria were included.

RESULTS

The search was performed on several online databases such as PubMed, Scopus, Embase, ProQuest, and Google Scholar from inception until January 2020. Among the initial search, 245 studies were found. After removing duplicated data and meeting the inclusion criteria, only 14 studies were selected. They included the effects of NS and its bioactive compounds as anti-hyperglycemic (n = 5), on liver function (n = 4), cancers (n = 3), and on Neuroinflammation and Atherosclerosis (n = 2). Most of the included studies are animals or in-vitro investigations.

CONCLUSION

In this review, we discuss the latest findings on the molecular mechanism of NS effecting the AMPK signaling pathway. We also focus on the therapeutic effects of NS, including the prevention and treatment of metabolic and pro-inflammatory disease by targeting the AMPK pathway.

The Effect of Nigella Sativa on Renal Oxidative Injury in Diabetic Rats

Oxidative stress plays a key role in the evolution of diabetes complications. The current study looked into the potential effects of the hydroalcoholic extract of Nigella sativa on the oxidative injury of the rat kidneys in diabetic animals. The animals were placed into five study groups in a random manner as follows: (1) control, (2) diabetic, (3 and 4) treatment with two doses of N. sativa extract (200 and 400 mg/kg), and (5) treatment with metformin (300 mg/kg). The time course of administration was six weeks. The malondialdehyde (MD A) and total thiol groups, as well as the superoxide dismutase and catalase activities, were also assessed in the renal tissue and lipid profile in serum. In the diabetic groups, the level of MDA significantly increased (P < 0.01) and antioxidant levels decreased compared to the control (P < 0.05). In treated rats with N. sativa, the antioxidant status of renal tissue was improved (P < 0.05 to P < 0.001). The lipid profile also improved in the rats treated with the extract (P < 0.001). Our findings suggest that long-term administration of N. sativa in diabetic rats induced by streptozotocin can improve the status of the oxidative stress in kidney tissue.

Effect of Nigella sativa and Fenugreek on the Pharmacokinetics and Pharmacodynamics of Amlodipine in Hypertensive Rats

BACKGROUND

The present article is related to in-vitro and in-vivo herb-drug interaction studies.

OBJECTIVES

This study aimed to investigate the effect of Nigella sativa and fenugreek on the pharmacodynamics and pharmacokinetics of amlodipine.

METHOD

Hypertensive rats of group-I were treated with amlodipine and rats of group-II and III were treated with N. sativa, and N. sativa + amlodipine and fenugreek, and fenugreek + amlodipine, respectively. Systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean blood pressure (MBP) of group-I, II and III rats were measured by the "tail-cuff system".

RESULTS

N. sativa, as well as fenugreek, reduced the SBP, DBP and MBP. Simultaneously, administration of fenugreek + amlodipine or N. sativa + amlodipine showed better control of BP. Individually, fenugreek, as well as N. sativa, showed a surprising reduction in the heart rate. There was no remarkable effect of any of these two herbs on Cmax, AUC0-t, Kel, and terminal elimination half-life of amlodipine, but fenugreek altered the Tmax of amlodipine significantly, from 2 ± 1.2h in control to 7.2 ± 1.7h in fenugreek treated group, probably by delaying the absorption.

CONCLUSION

Results of pharmacodynamics and pharmacokinetics studies suggested that simultaneous administration of fenugreek or N. sativa with amlodipine improved the pharmacological response of amlodipine in hypertensive rats, though there was no remarkable change in pharmacokinetic parameters (Cmax, Kel, elimination t1/2, and AUC0-t).

Effects of Nigella sativa on glycemic control, lipid profiles, and biomarkers of inflammatory and oxidative stress: A systematic review and meta-analysis of randomized controlled clinical trials

The aim of this systematic review and meta-analysis was to evaluate the effects of Nigella sativa (N. sativa) on glycemic control, lipid profiles, and biomarkers of inflammatory and oxidative stress. Two independent authors systematically examined online databases consisting of, EMBASE, Scopus, PubMed, Cochrane Library, and Web of Science from inception until October 30, 2019. Cochrane Collaboration risk of bias tool was applied to assess the methodological quality of the studied trials. The heterogeneity among the included studies were assessed using the Cochrane's Q test and I-square (I² ) statistic. Data were pooled using a random-effects model and weighted mean difference (WMD) was considered as the overall effect size. A total of 50 trials were included in this meta-analysis. We found a significant reduction in total cholesterol (WMD: -16.80; 95% CI: -21.04, -12.55), triglycerides (WMD: -15.73; 95% CI: -20.77, -10.69), LDL-cholesterol (WMD: -18.45; 95% CI: -22.44, -14.94) and VLDL-cholesterol (WMD: -3.72; 95% CI: -7.27, -0.18) following supplementation with N. sativa. In addition, there was significant reductive effect observed with N. sativa on fasting glucose (WMD: -15.18; 95% CI: -19.82, -10.55) and HbA1C levels (WMD: -0.45; 95% CI: -0.66, -0.23). Effects of N. sativa on CRP (WMD: -3.61; 95% CI: -9.23, 2.01), TNF-α (WMD: -1.18; 95% CI: -3.23, 0.86), TAC (WMD: 0.31; 95% CI: 0.00, 0.63), and MDA levels (WMD: -0.95; 95% CI: -2.18, 0.27) were insignificant. This meta-analysis demonstrated the beneficial effects of N. sativa on fasting glucose, HbA1c, triglycerides, total-, VLDL-, LDL-cholesterol levels.

Effects of Nigella sativa on endothelial dysfunction in diabetes mellitus: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Endothelial dysfunction is involved in lesion generation by the promotion of both early and late mechanism(s) of atherosclerosis such as adhesion molecules up-regulation, increased chemokine secretion and leukocyte adherence, increased cell permeability, enhanced low-density lipoprotein oxidation, cytokine elaboration, platelet activation and vascular smooth muscle cell migration, and proliferation. Nigella sativa is from the Ranunculaceae family which is used in some countries for various medicinal purposes. Nigella sativa seed has been widely used in traditional medicine for the treatment of diabetes.

AIM OF THE REVIEW

This review article summarized the therapeutic effects of Nigella sativa on endothelial dysfunction.

METHODS

Databases such as PubMed, Web of Science, Google Scholar, Scopus, and Iran Medex were considered. The search terms were " Nigella sativa " or "endothelium" and " Diabetes"," endothelial dysfunction ", " Thymoquinone " and " anti-inflammatory effect ".

RESULTS

The current review shows that Nigella sativa and Thymoquinone have a protective effect on endothelial dysfunction induced by diabetes. This is done by several mechanisms such as reduction of inflammatory and apoptotic markers, improving hyperglycemia, hyperlipidemia and antioxidant function, inhibiting platelet aggregation, and regulating eNOS, VCAM-1 and LOX-1 genes expression that involve in the endothelial dysfunction. Thymoquinone also reduces expression and secretion of some cytokines such as MCP-1, interleukin-1β, TNF-α, NF-κB, and Cox-2 that result in anti-inflammation effect.

CONCLUSION

Thymoquinone, the main phenolic terpene found in Nigella sativa, has several important properties such as antidiabetic, anti-inflammatory, and antioxidant activity. Therefore, Nigella sativa can improve endothelial dysfunction.

Potential role of cinnamaldehyde and costunolide to counteract metabolic syndrome induced by excessive fructose consumption

Background

One of the serious public health problems in the world is metabolic syndrome. It includes visceral obesity, dyslipidemia, insulin resistance, hyperglycemia, and hypertension. As a contributor to almost all the classic signs of metabolic syndrome, fructose was the ideal choice. There are certain shortcomings with existing drugs for insulin-resistant treatment. Plants still represent the main source of most available medicines. Cinnamaldehyde (CNA) is an active principle of Cinnamomum zeylanicum. Costunolide (CE) is natural sesquiterpene lactones, which is the main bioactive constituent of Saussurea lappa. The main aim of the present study is to investigate the effect of the synthetic antidiabetic agent (metformin) in comparison with natural constituents (cinnamaldehyde, costunolide) after developing a reliable model for insulin resistance by using high fructose diet (HFD).

Results

It was found that HFD increased plasma glucose, insulin, glycosylated hemoglobin, HbA1c, serum total cholesterol, LDL-cholesterol, triglyceride, ALT, AST, creatinine, and uric acid. Moreover, HFD decreased hepatic reduced glutathione and superoxide dismutase levels. While oral administration of cinnamaldehyde and costunolide significantly decreased plasma glucose, HbA1c, total cholesterol, LDL-cholesterol, triglyceride, and increased level of hepatic reduced glutathione and superoxide dismutase activity. Also, cinnamaldehyde and costunolide restored the altered plasma levels of ALT, AST, creatinine, and uric acid to normal.

Conclusions

The results of this experimental study showed that cinnamaldehyde and costunolide could be used as safe drugs for treating different abnormalities of metabolic syndrome.

Effects of Nigella Sativa on Type-2 Diabetes Mellitus: A Systematic Review

Diabetes mellitus is one of the most prevalent metabolic disorders that affect people of all genders, ages, and races. Medicinal herbs have gained wide attention from researchers and have been considered to be a beneficial adjuvant agent to oral antidiabetic drugs because of their integrated effects. Concerning the various beneficial effects of Nigella sativa, this systematic review aims to provide comprehensive information on the effects of Nigella sativa on glucose and insulin profile status in humans. A computerized database search performed through Scopus and Medline via Ebscohost with the following set of keywords: Nigella Sativa OR black seed oil OR thymoquinone OR black cumin AND diabetes mellitus OR hyperglycemia OR blood glucose OR hemoglobin A1C had returned 875 relevant articles. A total of seven articles were retrieved for further assessment and underwent data extraction to be included in this review. Nigella sativa was shown to significantly improve laboratory parameters of hyperglycemia and diabetes control after treatment with a significant fall in fasting blood glucose, blood glucose level 2 h postprandial, glycated hemoglobin, and insulin resistance, and a rise in serum insulin. In conclusion, these findings suggested that Nigella sativa could be used as an adjuvant for oral antidiabetic drugs in diabetes control.

Anil Kumar N, Sharopov F, Ramírez-Alarcón K, Ruiz-Ortega A, Abdulmajid Ayatollahi S, Valere Tsouh Fokou P, Kobarfard F, Amiruddin Zakaria Z, Iriti M, Taheri Y, Martorell M, Sureda A, N. Setzer W, Durazzo A, Lucarini M, Santini A, Capasso R, Adrian Ostrander E, -ur-Rahman A, Iqbal Choudhary M, C. Cho W, Sharifi-Rad J. Antidiabetic Potential of Medicinal Plants and Their Active Components

Diabetes mellitus is one of the major health problems in the world, the incidence and associated mortality are increasing. Inadequate regulation of the blood sugar imposes serious consequences for health. Conventional antidiabetic drugs are effective, however, also with unavoidable side effects. On the other hand, medicinal plants may act as an alternative source of antidiabetic agents. Examples of medicinal plants with antidiabetic potential are described, with focuses on preclinical and clinical studies. The beneficial potential of each plant matrix is given by the combined and concerted action of their profile of biologically active compounds.

Effect of Nigella Sativa oil versus metformin on glycemic control and biochemical parameters of newly diagnosed type 2 diabetes mellitus patients

PURPOSE

Nature is a phenomenal treasure of remedies. Numerous previous studies reported that Nigella sativa NS improved glycemic control, reduced insulin resistance, and improved lipid profile. NS was never investigated before as a monotherapy for newly diagnosed type 2 diabetes mellitus T2DM patients. Our aim was to investigate the potential metabolic benefits of NS monotherapy in newly diagnosed T2DM patients.

METHOD

Prospective, open-label randomized clinical trial at outpatient endocrinology clinic at Ain-Shams University hospital. Eligible patients were randomly assigned to either metformin tablets or NS oil capsules. Both groups received treatment for 3 months. Glycemic index (FBG, 2 h pp, A1C, insulin sensitivity %S, secretory function %B, insulin resistance IR), lipid profile (TC, LDL, HDL, TG), liver and kidney functions (AST, ALT, Sr cr), total antioxidant capacity TAC, weight, waist circumference WC and body mass index BMI were assessed at baseline and at the end of treatment period.

RESULTS

A concentration of 1350 mg/day NS in newly diagnosed T2DM patients was inferior to metformin in terms of lowering FBG, 2 h pp, and A1C or increasing %B. However, NS was comparable to metformin in lowering weight, WC, and BMI significantly. NS was comparable to metformin in regards of their effects on fasting insulin, %S, IR, ALT, TC, LDL, HDL, TG, and TAC. Metformin showed significant increase in AST and creatinine which was reserved in NS group.

CONCLUSION

NS administration in newly diagnosed T2DM was tolerable with no side effects as compared to metformin; however, it was inferior to metformin in terms of diabetes management.

Effects of Nigella sativa seeds (black cumin) on insulin secretion and lipid profile: A pilot study in healthy volunteers

It has been claimed that Nigella sativa seeds (NSS), also known as black cumin, have antidiabetic and lipid-lowering properties. Our pilot study investigated the effects of powdered NSS on insulin secretion and lipid profile in healthy male volunteers. We conducted a double-blind, randomized, placebo-controlled 4-week trial in 30 subjects, receiving NSS powder (1 g/day) or placebo orally (15 subjects/group). Insulin secretion as determined by the hyperglycaemic clamp technique, insulin sensitivity as well as cholesterol and triglycerides serum concentrations, were measured before and after treatment. NSS powder administration was clinically well tolerated. It did not modify fasting glycaemia and insulinaemia, and was ineffective on glucose-induced insulin secretion and insulin sensitivity. No significant changes on serum lipids were observed after treatment in any treatment groups, nor between the two treatment groups. However, in the treated group only, there was a significant correlation between total cholesterol change after treatment and its baseline level (r = -0.71, P = 0.006, n = 13), and between low-density lipoprotein (LDL) cholesterol change after treatment and its baseline level (r = -0.74, P = 0.004, n = 13). No such correlations were found for high-density lipoprotein (HDL) cholesterol, and for triglycerides. These results do not confirm any NSS effect on glucose regulation; however, they suggest that NSS powder may be of interest in lowering lipid concentrations in hyperlipidaemic subjects.