**4. The immunomodulation effect**

The immunomodulation effect may be useful in controlling the cytokine storm that occurs late among critically ill SARS-CoV-2 infected patients.

It was reported among several patients. A noticeable elevation of both IL-6 and IL-10 levels in response to SARS-CoV-2 infection. Virus results in the increase in cytokines IL-6 and IL-10 [4]. This immune reaction may lead to a cytokine storm then followed by a failure of several body organs, which may lead to death. It was suggested that some chloroquine derivatives may retain immunomodulatory activity and may be able to subdue the reactions of an immune response. This may help in early intervention as well as avoid the most likely bad scenario of the infection to a life-threatening status [5].

Pro-inflammatory cytokines, for example, IL-6 and IL-10, may result in expression induced by LPS. However, modulating several intracellular signaling pathways in macrophages and halting LPS-induced cytokines production by decreasing the mRNA stability by suppressing ERK1/2 activation. This hypothesis could be accomplished by a series of naturally isolated compounds, for example, luteolin, syringic acid, apigenin, curcumin, and lichochalcone, at the transcriptional level [6].

Complestan Eurystan A

#### *Antiviral Drugs - Intervention Strategies*

In *conclusion*, there is always hope to find potent, safe, and economic therapeutic agents for the treatment and management of COVID-19 outbreak from the commonly abundant natural products, such as phytosterols, alpha-ketoamides, and flavonoids. However, these findings need further investigation and experimental studies to be approved, but this could open the door for the utilization of abundantly available natural products to provide a therapeutic strategy via developing safe, effective, and economic drugs against this pandemic.
