Elucidation of mechanisms of actions of thymoquinone-enriched methanolic and volatile oil extracts from Nigella sativa against cardiovascular risk parameters in experimental hyperlipidemia

Protective effect of thymoquinone nanoemulsion in reducing the cardiotoxic effect of 5-fluorouracil in rats

5-Fluorouracil (5-FU), which is one of the most widely used chemotherapy drugs, has various side effects on the heart. Thymoquinone (TMQ), the main bioactive component of Nigella sativa, has antioxidant and protective effects against toxicity. In this study, we investigated the protective effect of thymoquinone against cardiotoxicity caused by 5-FU in vitro and in vivo models. H9C2 cells were exposed to 5-FU and TMQ, and cell viability was evaluated in their presence. Also, 25 male Wistar rats were divided into five control groups, 5-FU, 2.5, and 5 mg TMQ in nanoemulsion form (NTMQ) + 5-FU and 5 mg NTMQ. Cardiotoxicity was assessed through electrocardiography, cardiac enzymes, oxidative stress markers, and histopathology. 5-FU induced cytotoxicity in H9c2 cells, which improved dose-dependently with NTMQ cotreatment. 5-FU caused body weight loss, ECG changes (increased ST segment, prolonged QRS, and QTc), increased cardiac enzymes (aspartate aminotransferase [AST], creatine kinase-myocardial band [CK-MB], and lactate dehydrogenase [LDH]), oxidative stress (increased malondialdehyde, myeloperoxidase, nitric acid; decreased glutathione peroxidase enzyme activity), and histological damage such as necrosis, hyperemia, and tissue hyalinization in rats. NTMQ ameliorated these 5-FU-induced effects. Higher NTMQ dose showed greater protective effects. Thus, the results of our study indicate that NTMQ protects against 5-FU cardiotoxicity likely through antioxidant mechanisms. TMQ warrants further research as an adjuvant to alleviate 5-FU chemotherapy side effects.

Protective potential of thymoquinone against cadmium, arsenic, and lead toxicity: A short review with emphasis on oxidative pathways

Heavy metals are among the most important environmental pollutions used in various industries. Their extensive use has increased human susceptibility to different chronic diseases. Toxic metal exposure, especially cadmium, arsenic, and lead, causes oxidative damages, mitochondrial dysfunction, and genetic and epigenetic modifications. Meanwhile, thymoquinone (TQ) is an effective component of Nigella sativa oil that plays an important role in preventing the destructive effects of heavy metals. The present review discusses how TQ can protect various tissues against oxidative damage of heavy metals. This review is based on the research reported about the protective effects of TQ in the toxicity of heavy metals, approximately the last 10 years (2010-2021). Scientific databases, including Scopus, Web of Science, and PubMed, were searched using the following keywords either alone or in combination: cadmium, arsenic, lead, TQ, and oxidative stress. TQ, as a potent antioxidant, can distribute to cellular compartments and prevent oxidative damage of toxic metals. However, depending on the type of toxic metal and the carrier system used to release TQ in biological systems, its therapeutic dosage range may be varied.

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.

The cellular mechanism of antipsychotic-induced myocarditis: A systematic review

Antipsychotic drug-induced myocarditis is a serious and potentially fatal adverse drug reaction characterized by inflammation of the heart muscle (myocardium) that typically develops within the first month after commencing an antipsychotic drug. Although the precise mechanism of this severe adverse drug reaction is unknown, multiple theories have been proposed with varying levels of support from cellular or animal studies. We conducted a systematic review, in accordance with PRISMA guidelines, of published preclinical and clinical studies investigating the cellular mechanism by which antipsychotic drugs induce myocarditis. A literature search including all studies available before December 10, 2022, yielded 15 studies that met our inclusion criteria. Antipsychotics examined in the included studies included clozapine (n = 13), ziprasidone (n = 1), amisulpride (n = 1), haloperidol (n = 1), levomepromazine (n = 1), olanzapine (n = 1), and sertindole (n = 1). The evidence suggests several overlapping mechanistic cascades involving: (1) increased levels of catecholamines, (2) increased proinflammatory cytokines, (3) increased reactive oxygen species (ROS), (4) reduced antioxidant levels and activity, and (5) mitochondrial damage. Notable limitations such as, a focus on clozapine, sample heterogeneity, and use of supratherapeutic doses will need to be addressed in future studies. Discovery of the mechanism by which antipsychotic drugs induce myocarditis will allow the development of clinically-useful biomarkers to identify those patients at increased risk prior to drug exposure. The development or repurposing of therapeutics to prevent or treat drug-induced myocarditis will also be possible and this will enable increased and safe use of antipsychotics for those patients in need.

Efficacy of nigella sativa oil on endothelial function and atherogenic indices in patients with coronary artery diseases: A randomized, double-blind, placebo-control clinical trial

A therapeutic compound with antioxidant and anti-inflammatory effects might be a practical approach in endothelial dysfunction caused by oxidation and inflammation associated with atherosclerosis. Therefore, we aim to examine the efficacy of Nigella sativa (NS) oil supplementation on endothelial function and atherogenic indices in coronary artery disease (CAD) patients. Sixty individuals aged between 35 to 65 years old were recruited and divided into two groups, receiving either 2 g/daily of NS oil or sunflower oil as the placebo for 8 weeks. Serum levels of adhesion molecules, oxidative markers, and atherogenic parameters were evaluated at the starting point and the end of supplementation. Serum levels of vascular cell adhesion protein 1 (sVCAM-1) [-264.44 95% C, (156.83, 372.04)], intercellular adhesion molecule 1 (sICAM-1) [-132.38 95% C, (40.64, 224.1)], and malondialdehyde (MDA) [-0.21 95% C, (0.03, 0.40)] declined significantly following NS supplementation, while total antioxidant capacity increased [0.03 95% C, (0.03, 0.16)]. NS oil supplementation demonstrated a potential beneficial effect on endothelial function by reducing ICAM-1, VCAM-1 levels and affecting oxidative markers. However, further studies are necessary to elucidate NS oil as a therapeutic agent and complementary therapy in patients with stable CAD.

Natural essential oils: A promising strategy for treating cardio-cerebrovascular diseases

ETHNOPHARMACOLOGICAL RELEVANCE

Essential oils (EO) are volatile compounds obtained from different parts of natural plants, and have been used in national, traditional and folk medicine to treat various health problems all over the world. Records indicate that in history, herbal medicines rich in EO have been widely used for the treatment of CVDs in many countries, such as China.

AIM OF THE STUDY

This review focused on the traditional application and modern pharmacological mechanisms of herbal medicine EO against CVDs in preclinical and clinical trials through multi-targets synergy. Besides, the EO and anti-CVDs drugs were compared, and the broad application of EO was explained from the properties of drugs and aromatic administration routes.

MATERIALS AND METHODS

Information about EO and CVDs was collected from electronic databases such as Web of Science, ScienceDirect, PubMed, and China National Knowledge Infrastructure (CNKI). The obtained data sets were sequentially arranged for better understanding of EO' potential.

RESULTS

The study showed that EO had significant application in CVDs at different countries or regions since ancient times. Aiming at the complex pathological mechanisms of CVDs, including intracellular calcium overload, oxidative stress, inflammation, vascular endothelial cell injury and dysfunction and dyslipidemia, we summarized the roles of EO on CVDs in preclinical and clinical through multi-targets intervention. Besides, EO had the dual properties of drug and excipients. And aromatherapy was one of the complementary therapies to improve CVDs.

CONCLUSIONS

This paper reviewed the EO on traditional treatment, preclinical mechanism and clinical application of CVDs. As important sources of traditional medicines, EO' remarkable efficacy had been confirmed in comprehensive literature reports, which showed that EO had great medicinal potential.

Effects of turmeric (Curcuma longa) and its constituent (curcumin) on the metabolic syndrome: An updated review

Metabolic syndrome (MS) involves people with the following risk factors: obesity, hypertension, high glucose level and hyperlipidemia. It can increase the risk of heart disease, stroke and type 2 diabetes mellitus. The prevalence of MS in the world's adult population is about 20%-25%. Today, there is much care to use medicinal plants. Turmeric (Curcuma longa) as well as curcumin which is derived from the rhizome of the plant, has been shown beneficial effects on different components of MS. Thus, the purpose of this manuscript was to introduce different in vitro, in vivo and human studies regarding the effect of turmeric and its constituent on MS. Moreover, different mechanisms of action by which this plant overcomes MS have been introduced. Based on studies, turmeric and its bioactive component, curcumin, due to their anti-inflammatory and antioxidant properties, have antidiabetic effects through increasing insulin release, antihyperlipidemic effects by increasing fatty acid uptake, anti-obesity effects by decreasing lipogenesis, and antihypertensive effects by increasing nitric oxide. According to several in vivo, in vitro and human studies, it can be concluded that turmeric or curcumin has important values as a complementary therapy in MS. However, more clinical trials should be done to confirm these effects.

A review on hypo-cholesterolemic activity of Nigella sativa seeds and its extracts

Nigella sativa (N. sativa) (Family Ranunculaceae) is a popular therapeutic herb in many parts of the world. It is widely used in traditional medical systems such as Unani, Ayurveda and Siddha. Seeds and oil have a long history of folkloric use in many medicinal and culinary systems. The seeds of N. sativa have long been used to treat a variety of illnesses and disorders. Studies on N. sativa and its therapeutic potential have been investigated. This includes anti-diabetic, anticancer, immune-modulatory, analgesic, antimicrobial, anti-inflammatory, spasmolytic, bronchodilator, hepato-protective, renal protective, gastro-protective, antioxidant properties, and several others. Nigella sativa contains thymoquinone. This is a bioactive component of the essential oil with medicinal benefits. Therefore, it is of interest to report a comprehensive data on the therapeutic usefulness of N. sativa in hypo-cholesterolemic activity.

Thymoquinone reduces mitochondrial damage and death of cardiomyocytes induced by clozapine

The generation of a reactive nitrenium ion by microsomal/mitochondrial cytochrome P450 (CYPs) from clozapine (CLZ) has been suggested as the main cause of cardiotoxicity by this drug. Previous studies indicated that thymoquinone (TQ) as an active constituent of Nigella sativa has pharmacological effects such as antioxidant, reactive oxygen species (ROS) scavenger, and inhibitory effect on CYPs enzymes. Therefore, we hypothesized that TQ with these pharmacological effects can reduce CLZ-induced toxicity in isolated cardiomyocytes and mitochondria. Rat left ventricular cardiomyocytes and mitochondria were isolated by collagenase perfusion and differential centrifugation respectively. Then, isolated cardiomyocytes and mitochondria were pretreated with different concentrations of TQ (1, 5, and 10 μmol/l) for 30 min and then followed by exposure to CLZ (50 μmol/l) for 6 h. After 6 h of incubation, using biochemical evaluations and flow cytometric analysis, the parameters of cellular toxicity including cytotoxicity, the level of oxidized/reduced glutathione (GSH/GSSG), malondialdehyde (MDA), reactive oxygen species (ROS) formation, lysosomal membrane integrity, mitochondria membrane potential (ΔΨm) collapse, and mitochondrial toxicity including succinate dehydrogenase (SDH) activity and mitochondrial swelling were analyzed. We observed a significant toxicity in isolated cardiomyocytes and mitochondria after exposure with CLZ which was related to ROS formation, oxidative stress, GSH depletion, lysosomal and mitochondrial damages, and mitochondrial dysfunction and swelling, while TQ pretreatment reverted the above toxic effect of CLZ on isolated cardiomyocytes and mitochondria. Our results indicate that TQ prevents and reverses CLZ-induced cytotoxicity and mitochondrial damages in isolated cardiomyocytes and mitochondria, providing an experimental basis for clinical treatment on CLZ-induced cardiotoxicity.

Cholesterol-lowering activity of natural mono- and sesquiterpenoid compounds in essential oils: A review and investigation of mechanisms using in silico protein-ligand docking

Mono- and sesquiterpenoids are the main chemical constituents of essential oils. Essential oils and their constituents have received increasing attention for lipid-lowering properties in both cell and animal models. Despite the chemical diversity of essential oil compounds, the effects of many of these compounds on cholesterol metabolism are highly similar. In this report, we review the literature regarding the effects of essential oils and their terpenoid constituents on cholesterol homeostasis, and explore likely mechanisms using protein-ligand docking. We identified 98 experimental and seven clinical studies on essential oils, isolated compounds, and blends; 100 of these described improvements either in blood cholesterol levels or in sterol metabolic pathways. Our review and docking analysis confirmed two likely mechanisms common to many essential oil compounds: (1) direct agonism of peroxisome-proliferator-activated receptors, and (2) direct interaction with sterol-sensing domains, motifs found in key sterol regulatory proteins including sterol regulatory element binding protein cleavage activating protein and HMG-CoA reductase. Notably, these direct interactions lead to decreased transcription and accelerated degradation of HMG-CoA reductase. Our work suggests that terpene derivatives in essential oils have cholesterol-lowering activity and could potentially work synergistically with statins, however, further high quality studies are needed to establish their clinical efficacy.

Amelioration effect of black seed oil against high-fat diet-induced obesity in rats through Nrf2/HO-1 pathway

Obesity is a chronic inflammatory disease that represents a risk factor for number of diseases including diabetes, steatohepatitis, and cancer. Using safe natural compounds to ameliorate obesity and its related metabolic syndrome is an interesting spot for research. We investigated the regulatory role and the underlying mechanism of black seed oil (BSO) on high-fat diet (HFD)-induced obesity in rats. The study included two models: the first one aimed to study the prophylactic effect of BSO (BSO administration for 10 weeks along with HFD) while the second one aimed to study the treatment role of BSO (BSO administration starting from the 10th week for 4 weeks along with HFD). BSO significantly decreased insulin resistance and body weight characteristics in both models. It also normalized lipid profile. Moreover, histopathological examination confirmed these results as BSO significantly decreased adipocyte size and hepatic lipid deposition. Besides, BSO alleviated HFD-induced oxidative stress as indicated by significant increase in the total antioxidant capacity and significant decrease in liver malondialdehyde. Moreover, BSO decreased significantly liver gluconeogenic enzymes mRNA expressions (phosphoenolpyruvate carboxykinase and glucose-6-phosphatase) and increased significantly heme oxygenase-1 (HO-1), nuclear factor erythroid-2-related factor-2 (Nrf2) and insulin receptor mRNA expressions. In conclusion, BSO represents a natural therapy that has the ability to prevent and treat HFD-induced obesity in rats that may be mediated through Nrf2/HO-1 pathway's activation and insulin receptor expression's increase. To our best knowledge, this study represents a novel study that investigates the regulatory role of BSO on Nrf2 pathway in preventing and treating HFD-induced obesity. PRACTICAL APPLICATIONS: Black seed oil is a natural available safe supplement, thus it can be used for prevention from obesity and even treatment of obesity and obesity related complications. Introducing of black seed oil in the treatment regimen of obese patients may be promising.

Therapeutic perspective of thymoquinone: A mechanistic treatise

The higher utilization of fruits and vegetables is well known to cure human maladies due to the presence of bioactive components. Among these compounds, thymoquinone, a monoterpene and significant constituent in the essential oil of Nigella sativa L., has attained attention by the researchers due to their pharmacologies perspectives such as prevention from cancer, antidiabetic and antiobesity, prevention from oxidative stress and cardioprotective disorder. Thymoquinone has been found to work as anticancer agent against different human and animal cancer stages including propagation, migration, and invasion. Thymoquinone as phytochemical also downregulated the Rac1 expression, mediated the miR-34a upregulation, and increased the levels of miR-34a through p53, as well as also regulated the pro- and antiapoptotic genes and decreased the phosphorylation of NF-κB and IKKα/β. In addition, thymoquinone also lowered the metastasis and ERK1/2 and PI3K activities. The present review article has been piled by adapting narrative review method and highlights the diverse aspects of thymoquinone such as hepatoprotective, anti-inflammatory, and antiaging through various pathways, and further utilization of this compound in diet has been proven effective against different types of cancers.

Phytotherapy for Cardiovascular Disease: A Bench-to-Bedside Approach

At present, cardiovascular disease (CVD) remains the leading cause of morbidity and mortality worldwide, and global trends suggest that this panorama will persist or worsen in the near future. Thus, optimization of treatment strategies and the introduction of novel therapeutic alternatives for CVD represent key objectives in contemporary biomedical research. In recent years, phytotherapy-defined as the therapeutic use of whole or minimally modified plant components-has ignited large scientific interest, with a resurgence of abundant investigation on a wide array of medicinal herbs (MH) for CVD and other conditions. Numerous MH have been observed to intervene in the pathophysiology of CVD via a myriad of molecular mechanisms, including antiinflammatory, anti-oxidant, and other beneficial properties, which translate into the amelioration of three essential aspects of the pathogenesis of CVD: Dyslipidemia, atherosclerosis, and hypertension. Although the preclinical data in this scenario is very rich, the true clinical impact of MH and their purported mechanisms of action is less clear, as large-scale robust research in this regard is in relatively early stages and faces important methodological challenges. This review offers a comprehensive look at the most prominent preclinical and clinical evidence currently available concerning the use of MH in the treatment of CVD from a bench-to-bedside approach.

Effects of Nigella sativa oil and thymoquinone against bisphenol A-induced metabolic disorder in rats

The underlying mechanisms of bisphenol A (BPA)-induced metabolic disorder and the protective impact of Nigella sativa oil (NSO) and thymoquinone (TQ) against BPA-induced metabolic disorder were investigated. Rats were treated as follows: Control, BPA (10 mg/kg), TQ (2 mg/kg), NSO (84 μL/kg), BPA + TQ (0.5, 1, 2 mg/kg), and BPA + NSO (21, 42, 84 μL/kg). BPA was administered by gavage, while, TQ and NSO were injected intraperitoneally (daily, 54 days). The weight, blood pressure, serum parameters [glucose, lipid profile, hepatic enzymes, insulin, interlukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), leptin, adiponectin], malondialdehyde (MDA), glutathione (GSH) and insulin signaling pathways [insulin receptor substrate (p-IRS,IRS); kinase (p-Akt,Akt); glycogen synthase kinase (p-GS3K,GS3K)] were measured. BPA increased the blood pressure, MDA, lipid profile, hepatic enzymes, insulin, IL-6, TNF-α, and leptin, and decreased the GSH and phosphorylated forms of IRS, Akt, GS3K but did not alter weight, glucose, IRS, AKT, and GS3K in the liver. Administration of NSO or TQ with BPA reduced the blood pressure, liver level of MDA, lipid profile, hepatic enzymes, insulin, IL-6, TNF-α, leptin, and increased the liver level of GSH and p-IRS, p-AKT, p-GS3K. TQ and NSO are thought to be effective in controlling metabolic disorders induced by BPA.

Aloe vera as an herbal medicine in the treatment of metabolic syndrome: A review

Metabolic syndrome (MS) is a highly prevalent health problem worldwide and is associated with different risk factors, including hyperglycemia, dyslipidemia, hypertension, and obesity. This condition increases the risk of developing type II diabetes mellitus and cardiovascular problems. The MS is one of the most important health concerns in industrialized countries and mainly results from a sedentary lifestyle, high levels of subjective stress, and unhealthy diets. Nowadays, the identification of appropriate health care approaches, such as herbal medicines, with fewer side effects is more favorable, especially with regard to the adverse effects of chemical drugs. Aloe barbadensis Miller known as Aloe vera is a useful plant with two major parts, including leaves that contain high concentrations of anthraquinone compounds and a clear gel. The gel is used as a food with several beneficial properties, such as antiinflammatory, antioxidant, antiviral, antibacterial, and wound-healing features. Other effects of A. vera, such as its lipid-lowering, antihypertensive, antidiabetic, antiobesity, and cardioprotective impacts, have been demonstrated in several studies. The present study was conducted to review the evidence on the pharmacological effects of A. vera on the different components of MS.

Nigella sativa L. seed regulated eNOS, VCAM-1 and LOX-1 genes expression and improved vasoreactivity in aorta of diabetic rat

ETHNOPHARMACOLOGICAL RELEVANCE

Nigella sativa L. seed has been widely used in traditional medicine for the treatment of diabetes. The major reason for vascular complications in diabetic patients is endothelial dysfunction. However, the impact of N. sativa seed on endothelial dysfunction in diabetes remains unclear.

AIM OF THE STUDY

This study was conducted to evaluate the effect of the hydroalcoholic extract of N. sativa seed on eNOS, VCAM-1, and LOX-1 genes expression and the vasoreactivity of aortic rings to acetylcholine (Ach) in streptozotocin (STZ)-induced diabetic rat.

MATERIALS AND METHODS

Treated rats received N. sativa seed extract (100, 200, and 400 mg/kg) daily by gavage for 6 weeks. The fasting blood glucose and lipids were measured and atherogenic index of plasma (AIP) was calculated. The endothelium-dependent vasoreactivity responses of isolated aortic rings were evaluated in the presence of cumulative concentrations of Ach (10^-8-10^-5 M). eNOS, VCAM-1, and LOX-1 genes expression in aortic tissue was assessed by using real time polymerase chain reaction (PCR).

RESULTS

Male diabetic Wistar rats treated with N. sativa seed extract for six weeks reduced serum glucose and lipids and improved AIP. The vasorelaxant responses of aortic rings to Ach were markedly improved. N. sativa seed significantly increased eNOS in mRNA expression level and function, while it decreased VCAM-1 and LOX-1 expressions in vascular cells of aortic tissue which assessed only in mRNA level.

CONCLUSIONS

The results of this study showed that N. sativa seed more likely, has antidiabetic and antihyperlipidemic properties and improved vasoreactivity, endothelial dysfunction, and vascular inflammation in diabetic rats' aorta.

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

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

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

Context. Nigella sativa seeds are usually used as traditional medicine for a wide range of therapeutic purposes. Objective. To investigate the subacute toxicity of NS aqueous extract and select its lowest dose to study its antidiabetic effect. Methods. 5 AqE.NS doses (2, 6.4, 21, 33, and 60 g/Kg) were daily administered to mice by gavage. Biochemical parameters measurements and histological study of the liver and the kidney were performed after 6 weeks of supplementation. Thereafter, and after inducing diabetes by alloxan, rats were treated by 2 g/Kg of AqE.NS during 8 weeks. Metabolic parameters were measured on sera. A horizontal electrophoresis of plasmatic lipoprotein was conducted. Glycogen, total lipids, and triglycerides were measured in the liver. TBARS were evaluated on adipose tissue, liver, and pancreas. Results. AqE.NS showed no variation in urea and albumin at the 5 doses, but hepatotoxicity from 21 g/Kg was confirmed by histopathological observations of the liver. In diabetic rats, AqE.NS significantly decreased glycemia, TG, T-cholesterol, LDL-c, and TBARS and showed a restored insulinemia and a significant increase in HDL-c. Results on the liver indicated a decrease in lipids and a possible glycogenogenesis. Conclusion. AqE.NS showed its safety at low doses and its evident antihyperglycemic, antihyperlipidemic, and antioxidant effect.

Andrographolide, a New Hope in the Prevention and Treatment of Metabolic Syndrome

Recently, the use of plant-derived medicines is increasing interest in the prevention and treatment of a variety of disorders including metabolic syndromes. Metabolic syndrome is one of the major risk factors for cardiovascular diseases (CVDs) and incidence of mortality worldwide. Scientific evidence suggests that Andrographis paniculata and its derived components, especially andrographolide (AGL) and its analogs/derivatives have a broad spectrum of biological activities. This review aims to sketch the activity of AGL and its analogs/derivatives against the components of metabolic syndromes such as diabetes, hyperlipidemia, hypertension, and obesity. Additionally, AGL activity against CVDs is also summarized. The finding suggests that AGL and its analogs/derivatives have a potential role in the management of metabolic syndrome; however, more studies should be conducted to evaluate their effectiveness.

Thymoquinone reduces kidney damage in apolipoprotein E-deficient mice fed a high-cholesterol diet

Hypercholesterolemia is a well-established risk factor for kidney injury that can lead to chronic kidney disease (CKD). Thymoquinone may be a potential therapeutic agent for kidney damage from hypercholesterolemia.

Anti-arthritogenic and cardioprotective action of hesperidin and daidzein in collagen-induced rheumatoid arthritis

Atherosclerosis has been linked to chronic inflammatory processes. Changes in the levels of lipoproteins, especially low-density lipoprotein or its variants, as well as inflammatory markers are risk factors for the atherosclerosis. In the present study, an experimental model of rheumatoid arthritis was developed by administrating collagen suspension intradermally in the tail region of Wistar albino rats. At the same time, a suspension of hesperidin (50 mg/kg body weight) and daidzein (20 mg/kg body weight) was orally administrated. The compounds were given in the morning and evening for 21 days. Levels of inflammatory markers in the homogenate of knee joints of experimental rats as well as plasma lipoproteins were investigated. The administration of hesperidin and daidzein caused significant (p < 0.001) decrease in articular elastase activity, TNF-α, and malondialdehyde levels. Further, arthritis scoring and histological findings supported the anti-inflammatory actions of the test compounds. Interestingly, the test compounds also lowered the plasma low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and triglyceride but increased the level of high-density lipoprotein cholesterol. The test compounds thus ameliorated the risk factors of atherosclerosis. Furthermore, antioxidant roles of hesperidin as well as daidzein were evident from decrease in free radical load demonstrated as increase in total antioxidant level in plasma of arthritic animals treated with hesperidin and daidzein. In a separate in vitro experiment, enhanced free radical scavenging activity of hesperidin was demonstrated against 2,2-diphenyl-1-picrylhydrazyl and 2,2-azinobis-3-ethylbenzothiazoline-6-sulfonic acid. The anti-inflammatory, hypolipidemic, and antioxidant actions of the naturally occurring test compounds, particularly hesperidin, seem to be quite effective against rheumatoid arthritis and atherosclerosis. Thus, their consumption may be helpful in prevention or at least delaying the onset of these diseases in susceptible individuals.

Minimization of the Risk of Diabetic Microangiopathy in Rats by Nigella sativa

BACKGROUND

Microangiopathy is a chronic diabetic complication resulting from metabolic derangements, oxidative stress, and increased pro-inflammatory cytokine production. Nigella sativa Linn. is used as an herbal medicine that exerts hypoglycemic, antilipidemic, anti-inflammatory, and antioxidant effects.

OBJECTIVE

To examine the effects of N. sativa extract on cutaneous microvascular changes in diabetic rats.

MATERIALS AND METHODS

Sprague-Dawley rats were randomly assigned into the following four groups: Untreated and N. sativa-treated normal controls and untreated and N. sativa-treated rats with streptozotocin-induced diabetes. A cold-pressed N. sativa extract was then orally administered (1000 mg/kg/day). After 8 weeks of treatment, the glucose, glycosylated hemoglobin (HbA1c), tumor necrosis factor-alpha (TNF-α), insulin levels, and lipid profile were determined in cardiac blood. Dermal capillary wall thickness was measured in tail skin sections stained with periodic acid-Schiff. Endothelial apoptosis was morphologically evaluated by hematoxylin and eosin staining.

RESULTS

Diabetes significantly reduced the circulating insulin and low-density lipoprotein levels and caused elevations in the glucose, HbA1c, and triglyceride levels, accompanied by a slight increase in total cholesterol levels and no change in the high-density lipoprotein and TNF-α levels. Capillary basement membrane thickening and a decreased capillary luminal diameter despite no evidence of endothelial cell apoptosis were also observed. N. sativa treatment of diabetic rats reduced the mean HbA1c concentration by 1.4%, enlarged the capillary lumens, and tended to attenuate dermal capillary basement membrane thickening without affecting the lipid profile or TNF-α level.

CONCLUSION

Our results indicate that N. sativa may be used to minimize the risk of diabetic microangiopathy, potentially due in part to its glycemic control activity.

SUMMARY

Diabetes causes dermal capillary basement membrane thickening and a decreased capillary luminal diameterNigella sativa treatment of diabetic rats enlarged the capillary lumens and tended to attenuate dermal capillary basement membrane thickeningN. sativa treatment of diabetic rats reduced the mean glycosylated hemoglobin concentration by 1.4%, which exceeds the necessary reduction previously described to decrease the risk of diabetic microangiopathy, without affecting the lipid profile or tumor necrosis factor-alpha levelN. sativa improves rat diabetic microangiopathy, potentially due in part to its glycemic control activity. Abbreviations used: H and E: Hematoxylin and eosin, HbA1c: Glycosylated hemoglobin, HDL-C: High-density lipoprotein cholesterol, LDL-C: Low-density lipoprotein cholesterol, PAS: Periodic acid-Schiff, STZ: Streptozotocin.

Nigella sativa (black seed) effects on plasma lipid concentrations in humans: A systematic review and meta-analysis of randomized placebo-controlled trials

The effects of Nigella sativa (NS) on plasma lipid concentrations are controversial. A systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to obtain a conclusive result in humans. PubMed-Medline, SCOPUS, Web of Science, and Google Scholar databases were searched (up to August 2015) to identify RCTs investigating the impact of NS on total cholesterol, LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), and triglycerides concentrations. A random-effects model and the generic inverse variance weighting method were used for quantitative data synthesis. Meta-regression, sensitivity analysis, and publication bias assessments were performed using standard methods. A total of 17 RCTs examining the effects of NS on plasma lipid concentrations were included. Meta-analysis suggested a significant association between NS supplementation and a reduction in total cholesterol (weighed-mean-difference [WMD]: -15.65mg/dL, 95% CI: -24.67, -6.63, p=0.001), LDL-C (WMD: -14.10mg/dL, 95% CI: -19.32, -8.88, p<0.001), and triglyceride levels (WMD: -20.64mg/dL, 95% CI: -30.29, -11.00, p<0.001). No significant effect on HDL-C concentrations (WMD: 0.28mg/dL, 95% CI: -1.96, 2.53, p=0.804) was found. A greater effect of NS seed oil versus seed powder was observed on serum total cholesterol and LDL-C levels, and an increase in HDL-C levels was found only after NS seed powder supplementation. NS has a significant impact on plasma lipid concentrations, leading to lower total cholesterol, LDL-C, and TG levels while increased HDL-C is associated with NS powder only. Further RCTs are needed to explore the NS benefits on cardiovascular outcomes.

Thymoquinone alleviates nonalcoholic fatty liver disease in rats via suppression of oxidative stress, inflammation, apoptosis

Nonalcoholic steatohepatitis (NAFLD) is a progressive form of liver disease that leads to advanced fibrosis. The present study was designed to assess the hepatoprotective effect of thymoquinone (TQ) on liver functions, insulin resistance, and PPAR-γ expression in NAFLD. Rats were divided into two main groups: one fed with normal rat chow diet and the other with high-fat high-cholesterol diet group for 6 weeks. Every group was subdivided into three subgroups (n = 8): treated with saline, low dose TQ (10 mg/kg), high dose TQ (20 mg/kg). High fat high cholesterol diet caused marked liver damage as noted in histopathology and significant increase in liver index, liver enzymes. There was significant increase in the insulin resistance, serum cholesterol, triglyceride, PPAR-γ gene overexpression with significant decrease in HDL. Additionally, oxidative stress increased by measuring MDA associated with significant decrease in serum total antioxidant capacity. As markers of inflammation, hepatic TNF-α was significantly increased with decrease in IL10. Further, there was increase in BAX protein with decrease in Bcl as compared to control group. This model of 6 weeks high-fat high-cholesterol diet showed minimal fibrosis as noticed by increase MMP2 and Masson trichrome satin. Co-treatment with TQ improved all previous parameters. High dose was more effective, although mostly non-statistically significant. TQ may have a promising agent to improve hepatic steatosis, oxidative stress; inflammatory, apoptotic status, fibrosis and so prevent liver damage in patients with NAFLD. Although PPAR-γ was significantly under-expressed by TQ, insulin resistance was improved significantly suggesting a role of liver damage.

Nigella sativa seed decreases endothelial dysfunction in streptozotocin-induced diabetic rat aorta

OBJECTIVE

Diabetes is an important risk factor for cardiovascular events. The great percent of morbidity in patients with diabetes is due to endothelial dysfunction. The present study investigated the effects of hydroalcholic extract of Nigella sativa (N. sativa) on contractile and dilatation response of isolated aorta in streptozotocin (STZ)-induced diabetic rat.

MATERIALS AND METHODS

Rats were divided into six experimental groups (control, untreated STZ-diabetic, and N. sativa hydroalcholic extract or metformin-treated diabetic rats). Treated rats received N. sativa extract (100, 200, and 400 mg/kg) or metformin (300 mg/kg) by gavage, daily for 6 weeks. Isolated rat thoracic rings were mounted in an organ bath system then contractile and dilatation responses induced by phenylephrine (PE), acetylcholine (ACh), potassium chloride (KCl), and sodium nitroprusside (SNP) were evaluated in different situations.

RESULTS

The lower concentrations of N. sativa seed extract (DE 100 and DE 200) and metformin significantly reduced the contractile responses to higher concentrations of PE (10(-6) - 10(-5) M) compared to diabetic group (p<0.05 to p<0.01). The relaxation response to Ach 10(-8) M, was increased in DE 200 and metformin groups compared to diabetic group (p<0.05). The relaxation responses to Ach 10(-7) - 10(-5) M were significantly higher in all treated groups compared to diabetic group (p<0.05 to p<0.001).

CONCLUSION

Chronic administration of N. sativa seed extract has a significant hypoglycemic effect and improves aortic reactivity to vasoconstrictor and vasodilator agents in STZ-induced diabetic rats.

Ameliorative effects of Nigella sativa on dyslipidemia

INTRODUCTION

Dyslipidemia is an established risk factor for ischemic heart disease. Nigella sativa (NS) is a medicinal plant that has been used for the treatment and prevention of a variety of diseases, in particular hyperlipidemia.

METHODS

We reviewed the existing literature published until 2014 by using the following keywords: ''Nigella sativa'', ''black cumin'', ''black seeds'', ''thymoquinone'', and ''lipid''.

RESULTS

In the conducted studies, different preparations of NS including seed powder (100 mg-20 g daily), seed oil (20-800 mg daily), thymoquinone (3.5-20 mg daily), and seed extract (methanolic extract especially), were shown to reduce plasma levels of total cholesterol, low-density lipoprotein cholesterol (LDL-C) and triglycerides, but the effect on high-density lipoprotein cholesterol (HDL-C) was not significant. NS and thymoquinone have been reported to be safe and well tolerated with no severe adverse effect. In clinical trials, NS was found to be effective when added as adjunct to standard antihyperlipidemic and antidiabetic medications. Lipid-modifying effects of NS could be attributed to the inhibition of intestinal cholesterol absorption, decreased hepatic cholesterol synthesis, and up-regulation of LDL receptors.

CONCLUSIONS

Overall, the evidence from experimental and a clinical studies suggests that NS seeds are a promising natural therapy for dyslipidemic patients.

Herbs with anti-lipid effects and their interactions with statins as a chemical anti- hyperlipidemia group drugs: A systematic review

BACKGROUND

The present systematic review aimed to express the clinical anti-lipid effects of different types of herbs, as well as described studied interactions between herbal remedies and prescribed drugs for hyperlipidemic patients which were based on in vitro experiments, animal studies, and empirical clinical experiences.

METHODS

For this systematic review, we explored 2183 published papers about herbal drugs interactions from November 1967 to August 2014, fulfilling eligibility criteria by searching in some databases such as Web of Science, Medline, Scopus, Embase, Cinahl, and the Cochrane database. The main keywords used for searching included: herbal medicine, herbs, statin, lipid, and herb-drug interaction.

RESULTS

Among published articles about herb-drug interactions, 185 papers met the initial search criteria and among them, 92 papers were potentially retrievable including a description of 17 herbs and medicinal plants. In first step and by reviewing all published manuscripts on beneficial effects of herbs on serum lipids level, 17 herbs were described to be effective on lipid profile as lowering serum triglyceride, total cholesterol, low-density lipoprotein cholesterol as well as increasing serum high-density lipoprotein level. Some herbs such as celery could even affect the hepatic triglyceride concentrations. The herbal reaction toward different types of statins is varied so that grapefruit or pomegranate was interacted with only some types of statins, but not with all statin types. In this context, administration of herbal materials can lead to decreased absorption of statins or decreased the plasma concentration of these drugs.

CONCLUSION

Various types of herbs can potentially reduce serum lipid profile with the different pathways; however, the herb-drug interactions may decrease pharmacological therapeutic effects of anti-hyperlipidemic drugs that should be considered when approved herbs are prescribed.

Comparative Studies on Polyphenolic Composition, Antioxidant and Diuretic Effects of Nigella sativa L. (Black Cumin) and Nigella damascena L. (Lady-in-a-Mist) Seeds

This study was performed to evaluate the phenolic profile, antioxidant and diuretic effects of black cumin and lady-in-a-mist seeds. In the phenolic profile, differences between the two species are significant. Qualitative and quantitative analyses of the phenolic compounds were performed using a HPLC-UV/MS method. Hyperoside was the only identified flavonoid glycoside (1.08 ± 0.01 μg∙g⁻¹ dw plant material), in the N. damascena extract. Regarding the flavonol profile, kaempferol was identified before the hydrolysis, only in the N. sativa extract (6.06 ± 0.02 μg∙g⁻¹ dw plant material) and quercetin only in N. damascena seeds (14.35 ± 0.02 μg∙g⁻¹ dw plant material). The antioxidant potential of the two species was tested through several electron transfer assays, which indicated, excepting for the FRAP assay, N. damascena as exhibiting a higher free radical scavenging activity. The diuretic activity of the two extracts was tested using a rat-experimental model on acute diuresis. Administration of the ethanolic extract of N. sativa (100 mg∙kg⁻¹) resulted in a significant increase in urine volume, although less than found with the reference drug; in addition N. damascena extract did not present a diuretic effect. In reference to the elimination of Na⁺, K⁺ and uric acid, the black cumin extract exhibited a higher natriuretic than kaluretic effect and a similar uricosuric effect with control and N. damascena. For N. damascena, the Na⁺/K⁺ ratio was sub unitary, but not due to an increasing of the kaluretic effect, but mostly to a decrease of Na⁺ excretion.

Hypocholesterolemic and choleretic effects of three dimethoxycinnamic acids in relation to 2,4,5-trimethoxycinnamic acid in rats fed with a high-cholesterol/cholate diet

BACKGROUND

2,4,5-Trimethoxycinnamic acid (2,4,5-TMC) is the major and non-toxic metabolite of α-asarone, which retains hypocholesterolemic and choleretic activities. We compared the activities of 2,4,5-TMC with those of 2,4-dimethoxycinnamic acid (2,4-DMC), 3,4-DMC and 3,5-DMC, to understand the role of the methoxyls on carbons 2, 4 and 5 on the pharmacologic properties of these compounds.

METHODS

The methoxycinnamic acids were administered to high-cholesterol/cholate-fed rats. We measured bile flow, and quantified bile acids, phospholipids and cholesterol in bile, and cholesterol and cholesterol-lipoproteins in serum. The inhibition of HMG-CoA reductase by the methoxycinnamic acids was evaluated in vitro.

RESULTS

The four methoxycinnamic acids decreased serum cholesterol, without affecting the concentration of HDL-cholesterol. 2,4,5-TMC produced the highest decrease in LDL-cholesterol, 73.5%, which exceeds the range of statins (20-40%), and produced the highest inhibition of the activity of HMG-CoA reductase. 3,4-DMC produced the highest increase in bile flow, bile acids and phospholipids concentrations, and reduction in bile cholesterol, which led to a decrease in the biliary cholesterol saturation index.

CONCLUSIONS

2,4,5-TMC (which has three methoxyls) had the highest hypocholesterolemic activity, while 3,4-DMC, which lacks the methoxyl in carbon 2 but conserves the two other methoxyls in an adjacent position, had the highest choleretic activity and a probable cholelitholytic activity. In methoxycinnamic acids with two methoxyls in non-adjacent positions (2,4-DMC and 3,5-DMC), the hypocholesterolemic and choleretic activities were not as evident. 2,4,5-TMC and 3,4-DMC, which did not cause liver damage during the treatment period, should be further explored as a hypocholesterolemic and choleretic compounds in humans.

The relaxant effect of Nigella sativa on smooth muscles, its possible mechanisms and clinical applications

Nigella sativa (N. sativa) is a spice plant which has been traditionally used for culinary and medicinal purposes. Different therapeutic properties including the beneficial effects on asthma and dyspnea, digestive and gynecology disorders have been described for the seeds of N. sativa. There is evidence of the relaxant effects of this plant and some of its constituents on different types of smooth muscle including rabbit aorta, rabbit jejunum and trachea. The relaxant effect of N. sativa could be of therapeutic importance such as bronchodilation in asthma, vasodilation in hypertension and therapeutic effect on digestive or urogenital disorders. Therefore in the present article, the relaxant effects of N. sativa and its constituents on smooth muscles and its possible mechanisms as well as clinical application of this effect were reviewed.

A review of the effects of Nigella sativa L. and its constituent, thymoquinone, in metabolic syndrome

BACKGROUND

Metabolic syndrome is an important risk factor for cardiovascular disease (CVD) occurrence and mortality. CVDs are leading cause of death worldwide. Recently, there has been an increasing interest in the use of herbal medicines with more efficiency and minimal undesirable effects than chemical drugs for a variety of disorders including CVD. Nigella sativa and its active constituent, thymoquinone, have been documented to exhibit antidiabetic, antiobesity, hypotensive and hypolipidemic properties.

AIM

In this review, we discussed the most relevant articles to find out the role of N. sativa in different components of metabolic syndrome and CVD risk factors including high blood pressure, obesity, dyslipidemia and high blood glucose.

CONCLUSIONS

This review suggests a potential role of N. sativa and TQ in the management of metabolic syndrome, however more studies should be conducted to evaluate their effectiveness.

Induction of apolipoprotein A-I gene expression by black seed (Nigella sativa) extracts

CONTEXT

Black seed [Nigella sativa L. (Ranunculaceae)] has been shown in animal models to lower serum cholesterol levels.

OBJECTIVES

In order to determine if extracts from black seed have any effects on high-density lipoprotein (HDL), we characterized the effects of black seed extract on apolipoprotein A-I (apo A-I) gene expression, the primary protein component of HDL.

MATERIALS AND METHODS

Hepatocytes (HepG2) and intestinal cells (Caco-2) were treated with black seed extracts, and Apo A-I, peroxisome proliferator-activated receptor α (PPARα), and retinoid-x-receptor α (RXRα) were measured by Western blot analysis. Apo A-I mRNA levels were measured by quantitative real-time polymerase chain reaction and apo A-I gene transcription was measured by transient transfection of apo A-I reporter plasmids.

RESULTS

Extracts from black seeds significantly increased hepatic and intestinal apo A-I secretion, as well as apo A-I mRNA and gene promoter activity. This effect required a PPARα binding site in the apo A-I gene promoter. Treatment of the extract with either heat or trypsin had no effect on its ability to induce apo A-I secretion. Treatment with black seed extract induced PPARα expression 9-fold and RXRα expression 2.5-fold. Furthermore, the addition of PPARα siRNA but not a control siRNA prevented some but not all the positive effects of black seed on apo A-I secretion.

DISCUSSION

Black seed extract is a potent inducer of apo A-I gene expression, presumably by enhancing PPARα/RXRα expression.

CONCLUSIONS

We conclude that black seed may have beneficial effects in treating dyslipidemia and coronary heart disease.

Mitigating role of thymoquinone rich fractions from Nigella sativa oil and its constituents, thymoquinone and limonene on lipidemic-oxidative injury in rats

Therapeutic role of Nigella sativa (NS) seed oil fractions, methanolic extract (ME) and volatile oil (VO) and their constituents, thymoquinone (TQ) and limonene (LMN) in relation to lipidemic-oxidative stress in Wistar rats was determined. The total phenolic contents of NS seed oil and their ME and VO extracts were 320.00 ± 3.00, 300.12 ± 0.04 and 288.41 ± 0.01 mg gallic acid equivalents per 100 g of NS oil, respectively. Their Fe(+2) chelating activities were 870.00 ± 2.00, 222.31 ± 5.80 and 38.59 ± 1.43 mg EDTA equivalents per 100 g of NS oil, respectively. These fractions and compounds exhibited strong antioxidant activities against 2,2-diphenyl-1-picryl hydrazyl, 2,2-azinobis-3-ethylbenzothiazoline-6-sulfonic acid, nitric oxide and hydroxyl radicals. Potential antiperoxidative effects of these fractions and compounds were also observed in liposome, and lipidemic-induced lipid peroxidation in atherogenic suspension fed rats, pretreated with 100 mg ME, 20 mg VO, 10 mg pure TQ or 200 mg LMN for 30 days. ME containing ω-6 linoleic acid and palmitic acid natural compounds was highly effective against lipidemic oxidative stress than VO extract possessing thymol and isothymol phenolic natural antioxidant compounds. TQ, principal compound shared to both the extracts. The test fractions and compounds effectively reduced the erythrocyte and liver lipid peroxidation markers, conjugated diene, lipid hydroperoxide and malondialdehyde to near normal levels in the order ME > TQ > VO > LMN, by directly counteracting free radicals as well as suppressing hepatic HMG-CoA reductase activity. Our findings demonstrated that these natural products, preferably ME possess significant antioxidant activities, and may be recommended as new potential sources of natural antioxidants.

Endothelium-independent vasorelaxant effects of hydroalcoholic extract from Nigella sativa seed in rat aorta: the roles of Ca2+ and K+ channels

Objective. The aim of this study was to elucidate the mechanism(s) responsible for the vasorelaxant effect of Nigella sativa (N. sativa). Methods. The activity of different concentrations of N. sativa extract was evaluated on contractile responses of isolated aorta to KCl and phenylephrine (PE). Results. The extract (2–14 mg/mL) induced a concentration dependent relaxation both in endothelium-intact and endothelium-denuded aortic rings precontracted by PE (10⁻⁶ M) and KCl (6 × 10⁻² M). Extract reduced PE- and KCl-induced contractions in presence of cumulative concentrations of calcium (10⁻⁵–10⁻² M) significantly. L-NAME and indomethacin had no effect on vasorelaxation effect of extract in PE-induced contraction. Diltiazem and heparin reduced significantly this vasorelaxation at a concentration of 14 mg/mL of extract; however, N. sativa-induced relaxation was not affected by ruthenium red. Tetraethylammonium chloride reduced the extract-induced relaxation in concentrations of 2–6 mg/mL of extract significantly but glibenclamide reduced this relaxative effect in all concentrations of extract. Conclusions. The inhibitory effect of N. sativa seed extract on the contraction induced by PE and KCl was endothelium-independent. This relaxation was mediated mainly through the inhibition of Ca²⁺ and K_ATP channels and also intracellular calcium release.

Short-term caraway extract administration improves cardiovascular disease risk markers in streptozotocin-induced diabetic rats: a dose-response study

OBJECTIVE

This study examined the effects of caraway plant on blood levels of glucose, lipid profile, and C-reactive protein in diabetic rats.

METHODS

Thirty two male Wistar rats were randomly divided into four groups: group 1: nondiabetic control rats, group 2: diabetic rats, group 3, and 4 (caraway treated diabetic groups): each rat was treated with caraway at doses of 1 g/kg in group 3 and 2 g/kg in group 4. Diabetes was induced by a single intraperitoneal injection of 60 mg/kg streptozotocin. Caraway was administered as aqueous extract orally once a day for 3 weeks. Finally, blood samples were collected and fasting blood glucose, serum lipid profile, and C-reactive protein levels were determined. Data were analyzed statistically by one-way Analysis of Variance and considered to be significant when p < .05.

RESULTS

Diabetic rats receiving 1 and 2 g/kg caraway extracts had significantly lower total cholesterol (p = .036 and p = .010, respectively), low-density lipoprotein (p = .001 and p = .002, respectively), non-HDL-C (p = .003 and p = .007, respectively), LDL-C to HDL-C ratio (p = .002) and atherogenic index (p = .001) than that of diabetic control rats. Moreover, there were significant changes in fasting blood glucose in diabetic groups treated with 1 and 2 g/kg caraway extracts (p = .001 and p = .027, respectively) compared with the diabetic control. However, caraway did not have any significant effect on C-reactive protein level in diabetic rats.

CONCLUSION

This study suggests that caraway can exhibit blood glucose and lipid lowering activities in diabetes, without any effect on C-reactive protein level.