TNF and COVID-19: Furthermore, natural compounds such as gamma-oryzanol (the main bioactive constituent from rice bran and germ) have been introduced as a possible adjunctive therapy to prevent the cytokine storm in COVID-19 patients, as this compound positively increases the expression of PPARγ in adipose tissue and as a result reduces the levels of inflammatory cytokines including TNF-α, IL6, and MCP1 (157).