Revisiting pharmacological potentials of Nigella sativa seed: A promising option for COVID-19 prevention and cure

Abstract

Nigella sativa seed and its active compounds have been historically recognized as an effective herbal panacea that can establish a balanced inflammatory response by suppressing chronic inflammation and promoting healthy immune response. The essential oil and other preparations of N. sativa seed have substantial therapeutic outcomes against immune disturbance, autophagy dysfunction, oxidative stress, ischemia, inflammation, in several COVID-19 comorbidities such as diabetes, cardiovascular disorders, Kawasaki-like diseases, and many bacterial and viral infections. Compelling evidence in the therapeutic efficiency of N. sativa along with the recent computational findings is strongly suggestive of combating emerged COVID-19 pandemic. Also, being an available candidate in nutraceuticals, N. sativa seed oil could be immensely potential and feasible to prevent and cure COVID-19. This review was aimed at revisiting the pharmacological benefits of N. sativa seed and its active metabolites that may constitute a potential basis for developing a novel preventive and therapeutic strategy against COVID-19. Bioactive compounds of N. sativa seed, especially thymiquinone, α-hederin, and nigellidine, could be alternative and promising herbal drugs to combat COVID-19. Preclinical and clinical trials are required to delineate detailed mechanism of N. sativa's active components and to investigate their efficacy and potency under specific pathophysiological conditions of COVID-19.

Keywords: COVID-19; Nigella sativa; SARS-CoV-2 infection; autophagy; immune response; inflammation; oxidative stress.

FIGURE 1

Mechanisms involved in pharmacological effects of N. sativa on COVID‐19. Black cumin seed or its active compounds activate immune cells, initiate antigen presentation system, and make balance between Th1 and Th2 cytokines. The bioactive compounds of black cumin seed increase conversion of LC3II to LC3III, a marker of autophagy activation. Besides, black cumin decreases inflammation, oxidative stress (MDA) and increases anti‐inflammation, ant‐histamine responses, SOD, and GPx. Comorbodities increase the severity of SARS‐CoV‐2 infection. Black cumin may also be beneficial through improving comorbodity situation in SARS‐CoV‐2‐infected patients. CVD, cardiovascular disease; KLD, Kawasaki‐like diseases; PIMS, pediatric inflammatory multisystemic syndrome [Colour figure can be viewed at wileyonlinelibrary.com]