SARS-CoV-2 is a betacoronavirus causing severe inflammatory pneumonia, so that excessive inflammation is considered a risk factor for the disease. According to reports, cytokine storm is strongly responsible for death in such patients. Some of the consequences of severe inflammation and cytokine storms include acute respiratory distress syndrome, acute lung injury, and multiple organ dysfunction syndromes. Phylogenetic findings show more similarity of the SARS-CoV-2 virus with bat coronaviruses, and less with SARS-CoV. Quercetin is a carbohydrate-free flavonoid that is the most abundant flavonoid in vegetables and fruits and has been the most studied to determine the biological effects of flavonoids. Inflammasomes are cytosolic multi-protein complexes assembling in response to cytosolic PAMP and DAMPs, whose function is to generate active forms of cytokines IL-1β and IL-18. Activation or inhibition of the NLRP3 inflammasome is affected by regulators such as TXNIP, SIRT1 and NRF2. Quercetin suppresses the NLRP3 inflammasome by affecting these regulators. Quercetin, as an anti-inflammatory, antioxidant, analgesic and inflammatory compound, is probably a potential treatment for severe inflammation and one of the main life-threatening conditions in patients with COVID-19.

Curcumin is the effective ingredient of turmeric, sometimes used as a painkiller in traditional medicine. It has extensive biological properties such as anti‐inflammatory and antioxidant activities. SARS‐CoV‐2 is a betacoronavirus developing severe pneumonitis. Inflammasome is one of the most important components of innate immunity, which exacerbates inflammation by increasing IL‐1β and IL‐18 production. Studies on viral infections have shown overactivity of inflammasome and thus the occurrence of destructive and systemic inflammation in patients. NLRP3 inflammasome has been shown to play a key role in the pathogenesis of viral diseases. The proliferation of SARS‐CoV‐2 in a wide range of cells can be combined with numerous observations of direct and indirect activation of inflammasome by other coronaviruses. Activation of the inflammasome is likely to be involved in the formation of cytokine storm. Curcumin regulates several molecules in the intracellular signal transduction pathways involved in inflammation, including IBB, NF‐kBERK1,2, AP‐1, TGF‐β, TXNIP, STAT3, PPARγ, JAK2‐STAT3, NLRP3, p38MAPK, Nrf2, Notch‐1, AMPK, TLR‐4 and MyD‐88. Due to anti‐inflammatory and anti‐inflammasome properties without any special side effects, curcumin can potentially play a role in the treatment of COVID‐19 infection along with other drug regimens.

Immune dysregulation has been identified as a critical cause of the most common types of cardiovascular diseases (CVDs). Notably, the innate and adaptive immune responses under physiological conditions are typically regulated with high sensitivity to avoid the exacerbation of inflammation, but any dysregulation can probably be associated with CVDs. In this respect, progranulin (PGRN) serves as one of the main components of the regulation of inflammatory processes, which significantly contributes to the immunopathogenesis of such disorders. PGRN has been introduced among the secreted growth factors as one related to wound healing, inflammation, and human embryonic development, as well as a wide variety of autoimmune diseases. The relationship between the serum PGRN and TNF-α ratio with the spontaneous bacterial peritonitis constitute one of the independent predictors of these conditions. The full-length PGRN can thus effectively reduce the calcification of valve interstitial cells, and the granulin precursor (GRN), among the degradation products of PGRN, can be beneficial. Moreover, it was observed that, PGRN protects the heart against ischemia-reperfusion injury. Above all, PGRN also provides protection in the initial phase following myocardial ischemia-reperfusion injury. The protective impact of PGRN on this may be associated with the early activation of the PI3K/Akt signaling pathway. PGRN also acts as a protective factor in hyperhomocysteinemia, probably by down-regulating the wingless-related integration site Wnt/β-catenin signaling pathway. Many studies have further demonstrated that SARS-CoV-2 (COVID-19) has dramatically increased the risks of CVDs due to inflammation, so PGRN has drawn much more attention among scholars. Lysosomes play a pivotal role in the inflammation process, and PGRN is one of the key regulators in their functioning, which contributes to the immunomodulatory mechanism in the pathogenesis of CVDs. Therefore, investigation of PGRN actions can help find new prospects in the treatment of CVDs. This review aims to summarize the role of PGRN in the immunopathogenesis of CVD, with an emphasis on its treatment.