Saffron for "toning down" COVID-19-related cytokine storm: Hype or hope? A mini-review of current evidence.

AIM: To assess the potential role of saffron in downregulating inflammation and cytokine storm during COVID-19. MAIN FINDINGS: Three main compounds of saffron, i.e., crocetin esters, picrocrocin, and safranal, present strong antioxidant and anti-inflammatory action for several disease states (e.g., Alzheimer's, cancer, and depression) but have also been studied in COVID-19. In particular, based on our comprehensive review of both in vitro and in silico studies, saffron's essential oils and other constituents appear to have both immunomodulatory and anti-asthmatic actions; these actions can be particularly helpful to treat patients with respiratory symptoms due to COVID-19. Moreover, crocin appears to reduce the COVID-19-related cytokine cascade and downregulate angiotensin-converting enzyme 2 (ACE2) gene expression. Last, in silico studies suggest that saffron's astragalin and crocin could have inhibitory actions on SARS-CoV-2 protease and spike protein, respectively. CONCLUSION: Saffron represents a promising substance for toning down cytokine storm during COVID-19, as well as a potential preventive treatment for COVID-19. However, appropriate randomized clinical trials, especially those using biomarkers as surrogates to assess inflammatory status, should be designed in order to assess the clinical efficacy of saffron and allow its use as an adjunct treatment modality, particularly in resource-poor settings where access to drugs may be limited

<i style="mso-bidi-font-style:normal"><span style="font-size:11.0pt;mso-bidi-font-size:10.0pt;font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";mso-bidi-font-family:"Times New Roman"; mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language:AR-SA" lang="EN-US">In vitro</span></i><span style="font-size:11.0pt;mso-bidi-font-size: 10.0pt;font-family:"Times New Roman";mso-fareast-font-family:"Times New Roman"; mso-bidi-font-family:"Times New Roman";mso-ansi-language:EN-US;mso-fareast-language: EN-US;mso-bidi-language:AR-SA" lang="EN-US"> antimicrobial, antioxidant, and antiviral activities of the essential oil and various extracts from <i style="mso-bidi-font-style:normal">Thymus nummularis </i>M. Bieb.</span>

403-410<span style="font-size:11.0pt;mso-bidi-font-size: 10.0pt;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" mso-bidi-font-family:"times="" roman";mso-ansi-language:en-us;mso-fareast-language:="" en-us;mso-bidi-language:ar-sa"="" lang="EN-US">This study is designed to determine the in vitro antioxidant, antimicrobial and antiviral activities of hexane, chloroform, water extracts and essential oils of Thymus nummularis M. Bieb. Chemical composition of essential oil was determined by employing GC-MS and GC-FID analyses; thymol being the main component in 58 %<i style="mso-bidi-font-style: normal">. The oil and extracts were screened for their possible antioxidant activities by two complementary test systems, namely DPPH free radical scavenging and β-Carotene color bleaching test – a spectrophotometric method. The highest free radical scavenging activity was observed in the essential oil (IC50: 2.3 μg/ml) whilst, in β-Carotene color bleaching test, chloroform extract showed superiority<i style="mso-bidi-font-style: normal">, with an inhibition rate at 79.95 %. Antibacterial and antifungal activities of the extracts were also evaluated and among which the essential oil exerted better activity against all microorganisms tested except for Pseudomonas aeruginosa. Nevertheless, none was effective against test viruses, namely HSV and Influenza.</span