The Protective Effects of Pharmacologic Postconditioning of Hydroalcoholic Extract of Nigella sativa on Functional Activities and Oxidative Stress Injury During Ischemia-Reperfusion in Isolated Rat Heart

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.

Novel, Innovative Models to Study Ischemia/Reperfusion-Related Redox Damage in Organ Transplantation

The implementation of ex vivo organ machine perfusion (MP) into clinical routine undoubtedly helped to increase the donor pool. It enables not just organ assessment, but potentially regeneration and treatment of marginal organs in the future. During organ procurement, redox-stress triggered ischemia-reperfusion injury (IRI) is inevitable, which in addition to pre-existing damage negatively affects such organs. Ex vivo MP enables to study IRI-associated tissue damage and its underlying mechanisms in a near to physiological setting. However, research using whole organs is limited and associated with high costs. Here, in vitro models well suited for early stage research or for studying particular disease mechanisms come into play. While cell lines convince with simplicity, they do not exert all organ-specific functions. Tissue slice cultures retain the three-dimensional anatomical architecture and cells remain within their naïve tissue-matrix configuration. Organoids may provide an even closer modelling of physiologic organ function and spatial orientation. In this review, we discuss the role of oxidative stress during ex vivo MP and the suitability of currently available in vitro models to further study the underlying mechanisms and to pretest potential treatment strategies.

Prevention and Treatment of Cardiovascular Diseases with Plant Phytochemicals: A Review

Cardiovascular diseases (CVDs) are the world's leading killers, accounting for 30% deaths. According to the WHO report, CVDs kill 17.9 million people per year, and there will be 22.2 million deaths from CVD in 2030. The death rates rise as people get older. Regarding gender, the death rate of women by CVD (51%) is higher than that of men (42%). To decrease and prevent CVD, most people rely on traditional medicine originating from the plant (phytochemicals) in addition to or in preference to commercially available drugs to recover from their illness. The CVD therapy efficacy of 92 plants, including 15 terrestrial plants, is examined. Some medicinal plants well known to treat CVD are, Daucus carota, Nerium oleander, Amaranthus Viridis, Ginkgo biloba, Terminalia arjuna, Picrorhiza kurroa, Salvia miltiorrhiza, Tinospora cordifolia, Mucuna pruriens, Hydrocotyle asiatica, Bombax ceiba, and Andrographis paniculate. The active phytochemicals found in these plants are flavonoids, polyphenols, plant sterol, plant sulphur compounds, and terpenoids. A general flavonoid mechanism of action is to prevent low-density lipoprotein oxidation, which promotes vasodilatation. Plant sterols prevent CVD by decreasing cholesterol absorption in the blood. Plant sulphur compound also prevent CVD by activation of nuclear factor-erythroid factor 2-related factor 2 (Nrf2) and inhibition of cholesterol synthesis. Quinone decreases the risk of CVD by increasing ATP production in mitochondria while terpenoids by decreasing atherosclerotic lesion in the aortic valve. Although several physiologically active compounds with recognized biological effects have been found in various plants because of the increased prevalence of CVD, appropriate CVD prevention and treatment measures are required. More research is needed to understand the mechanism and specific plants' phytochemicals responsible for treating CVD.

Diabetic cardiomyopathy was attenuated by cinnamon treatment through the inhibition of fibro-inflammatory response and ventricular hypertrophy in diabetic rats

Diabetic cardiomyopathy (DCM) is a chronic complication of diabetes that emphasizes the urgency of developing new drug therapies. With an illustrious history in traditional medicine to improve diabetes, cinnamon has been shown to possess blood lipids lowering effects and antioxidative and anti-inflammatory properties. However, the extent to which it protects the diabetic heart has yet to be determined. Forty-eight rats were administered in the study and grouped as: control; diabetic; diabetic rats given 100, 200, or 400 mg/kg cinnamon extract, metformin (300 mg/kg), valsartan (30 mg/kg), or met/val (combination of both drugs), via gavage for six weeks. Fasting blood sugar (FBS) and markers of cardiac injury including creatine kinase-muscle/brain (CK-MB), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) were evaluated in blood samples. Malondialdehyde (MDA) levels, the total contents of thiol, superoxide dismutase (SOD), and catalase (CAT) activities were measured. Histopathology study and gene expression measurement of angiotensin II type 1 receptor (AT1), atrial natriuretic peptide (ANP), beta-myosin heavy chain (β-MHC), and brain natriuretic peptide (BNP) were done on cardiac tissue. FBS and cardiac enzyme indicators were reduced in all treated groups. A reduction in MDA level and enhancement in thiol content alongside with increase of SOD and CAT activities were observed in extract groups. The decrease of inflammation and fibrosis was obvious in treated groups, notably in the high-dose extract group. Furthermore, all treated diabetic groups showed a lowering trend in AT1, ANP, β-MHC, and BNP gene expression. Cinnamon extract, in addition to its hypoglycemic and antioxidant properties, can prevent diabetic heart damage by alleviating cardiac inflammation and fibrosis. PRACTICAL APPLICATIONS: This study found that cinnamon extract might protect diabetic heart damage by reducing inflammation and fibrosis in cardiac tissue, in addition to lowering blood glucose levels and increasing antioxidant activity. Our data imply that including cinnamon in diabetic participants' diets may help to reduce risk factors of cardiovascular diseases.

Thymoquinone ameliorates pressure overload-induced cardiac hypertrophy by activating the AMPK signalling pathway

Prolonged pathological myocardial hypertrophy leads to end‐stage heart failure. Thymoquinone (TQ), a bioactive component extracted from Nigella sativa seeds, is extensively used in ethnomedicine to treat a broad spectrum of disorders. However, it remains unclear whether TQ protects the heart from pathological hypertrophy. This study was conducted to examine the potential utility of TQ for treatment of pathological cardiac hypertrophy and if so, to elucidate the underlying mechanisms. Male C57BL/6J mice underwent either transverse aortic constriction (TAC) or sham operation, followed by TQ treatment for six consecutive weeks. In vitro experiments consisted of neonatal rat cardiomyocytes (NRCMs) that were exposed to phenylephrine (PE) stimulation to induce cardiomyocyte hypertrophy. In this study, we observed that systemic administration of TQ preserved cardiac contractile function, and alleviated cardiac hypertrophy, fibrosis and oxidative stress in TAC‐challenged mice. The in vitro experiments showed that TQ treatment attenuated the PE‐induced hypertrophic response in NRCMs. Mechanistical experiments showed that supplementation of TQ induced reactivation of the AMP‐activated protein kinase (AMPK) with concomitant inhibition of ERK 1/2, p38 and JNK1/2 MAPK cascades. Furthermore, we demonstrated that compound C, an AMPK inhibitor, abolished the protective effects of TQ in in vivo and in vitro experiments. Altogether, our study disclosed that TQ provides protection against myocardial hypertrophy in an AMPK‐dependent manner and identified it as a promising agent for the treatment of myocardial hypertrophy.

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

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

Nigella Plants - Traditional Uses, Bioactive Phytoconstituents, Preclinical and Clinical Studies

Nigella is a small genus of the family Ranunculaceae, which includes some popular species due to their culinary and medicinal properties, especially in Eastern Europe, Middle East, Western, and Central Asia. Therefore, this review covers the traditional uses and phytochemical composition of Nigella and, in particular, Nigella sativa. The pharmacological studies reported in vitro, in vivo, and in humans have also been reviewed. One of the main strength of the use of Nigella is that the seeds are rich in the omega-6 fatty acid linoleic acid and provide an extra-source of dietary phytochemicals, including the bioactive thymoquinone, and characteristics saponins, alkaloids, and flavonoids. Among Nigella species, N. sativa L. is the most studied plant from the genus. Due to the phytochemical composition and pharmacological properties, the seed and seed oil from this plant can be considered as good candidates to formulate functional ingredients on the basis of folklore and scientific knowledge. Nonetheless, the main limations are that more studies, especially, clinical trials are required to standardize the results, e.g. to establish active molecules, dosage, chemical profile, long-term effects and impact of cooking/incorporation into foods.

The molecular mechanism involved in cardioprotection by the dietary flavonoid fisetin as an agonist of PPAR-γ in a murine model of myocardial infarction

The methodology exploring the cardioprotective potential of the flavonoid Fisetin through its ability to modulate PPAR-γ was unraveled in the present study. Computational modelling through molecular docking based binding study of interactions between Fiestin and PPAR-γ revealed the potential role of Fisetin as an agonist of PPAR-γ. A murine model of cardiac ischemia-reperfusion injury was used to explore this further. Male Wistar Rats were randomly assigned to five groups. Fisetin (20 mg/kg; p. o) was administered for 28 days. Ischemia was induced for 45 min on the 29th day followed by 60 min of reperfusion. Fisetin pretreatment upregulated the expression of PPAR-γ in heart tissue significantly Cardioprotection was assessed by measurement of hemodynamic parameters, infarct size, ELISA for oxidative stress, immunohistochemistry and TUNEL assay for apoptosis, and western blot analysis for MAPK proteins and inflammation. PPAR-γ activation by fisetin led to significantly reduced infarct size, suppression of oxidative stress, reduction of cardiac injury markers, alleviation of inflammation, and inhibition of apoptosis The MAPK-based molecular mechanism showed a rise in a key prosurvival kinase, ERK1/ERK2 and suppression of JNK and p38 proteins. The aforementioned beneficial findings of fisetin were reversed on the administration of a specific antagonist of PPAR-γ. In conclusion, through our experiments, we have proved that fisetin protects the heart against ischemia-reperfusion injury and the evident cardioprotection is PPAR-γ dependant. In conclusion, our study has revealed a prime mechanism involved in the cardioprotective effects of fisetin. Hence, Fisetin may be evaluated in further clinical studies as a cardioprotective agent in patients undergoing reperfusion interventions.