Anti-cytokine Storm Activity of Fraxin, Quercetin, and their Combination on Lipopolysaccharide-Induced Cytokine Storm in Mice: Implications in COVID-19.

Background: Cytokine release syndrome (CRS) is the leading cause of mortality in advanced stages of coronavirus patients. This study examined the prophylactic effects of fraxin, quercetin, and a combination of fraxin+quercetin (FQ) on lipopolysaccharide-induced mice. Methods: Sixty mice were divided into six groups (n=10) as follows: control, LPS only, fraxin (120 mg/Kg), quercetin (100 mg/Kg), dexamethasone (5 mg/Kg), and FQ. All treatments were administered intraperitoneally (IP) one hour before induction by LPS (5 mg/Kg) IP injection. Twenty-four hours later, the mice were euthanized. Interleukin one beta (IL-1ß), interleukin 6 (IL-6), and tumor necrosis factor-alpha (TNF-α) were quantified using an enzyme-linked immunosorbent assay (ELISA), and lung and kidney tissues were examined for histopathological alterations. This study was conducted at Al-Nahrain University, Baghdad, Iraq, in 2022. Results: FQ reduced IL-1ß (P<0.001). All treatments significantly suppressed IL-6, fraxin, quercetin, dexamethasone, and FQ, all with P<0.001. The TNF-α level was reduced more with dexamethasone (P<0.001) and quercetin (P<0.001). Histopathological scores were significantly reduced mainly by quercetin and FQ in the lungs with scores of 12.30±0.20 (P=0.093), and 15.70±0.20 (P=0.531), respectively. The scores were 13±0.26 (P=0.074) and 15±0.26 (P=0.222) for quercetin and FQ in the kidneys, respectively. Conclusion: All used treatments reduced proinflammatory cytokine levels and protected against LPS-induced tissue damage.

Fraxin in Combination with Dexamethasone Attenuates LPS-Induced Liver and Heart Injury and Their Anticytokine Activity in Mice.

Background: Cytokine storm syndrome (CSS) is a major cause of morbidity and mortality in people suffering from hyperinflammatory status, which diverse etiological factors, including pathogens, therapeutic interventions, malignancies, and autoimmune disorders, can instigate. Since there is limited research on the antioxidant properties of fraxin and no studies have investigated its potential as an anticytokine storm agent, it is important to note that most studies have primarily focused on proinflammatory cytokines such as IL-1ß, IL-6, and TNFα during cytokine storm. However, little research discusses the role of chemokines, particularly IL-8, during cytokine storms. Therefore, further investigation is warranted into the role of fraxin as an anticytokine storm agent and the involvement of IL-8 in cytokine storms. The present study examines the preventive efficacy of fraxin and the combination of fraxin and dexamethasone (FD) in mitigating lipopolysaccharide-induced systemic inflammation in mice caused by Escherichia coli, 055: B5. Methods: Five groups of ten mice were randomly assigned: LPS only group (5 mg/kg, intraperitoneally i.p.), control (normal saline N.S. 1 ml/kg, i.p.), concentrations were selected based on previous literature, fraxin (120 mg/kg, i.p.), dexamethasone (5 mg/kg, i.p.), fraxin + dexamethasone (FD) (60 mg/kg + 2.5 mg/kg, i.p.), administered one hour before LPS injection (5 mg/kg,i.p.), animals were euthanized next day, and interleukin-8 (IL-8) was quantified in serum using an enzyme-linked immunosorbent assay. The liver and heart tissues underwent histopathological analysis to assess morphological changes. For data analysis using ANOVA and Tukey post hoc tests, the Kruskal-Wallis and Mann-Whitney U tests were employed to analyze the histological results. Results: A significant decline in IL-8 levels was recorded in the treatment groups almost to the same degree (p < 0.001), and the percentage of inhibition of IL-8 for fraxin, dexamethasone, and FD was 93%.92.4%, and 93%, respectively, compared to the LPS-only group. Histopathological scores were significantly reduced in liver and heart tissue (P < 0.05). Conclusions: All interventions used in this study significantly reduced interleukin-8 (IL-8) levels and reduced LPS-induced liver and cardiac damage. The combination (FD) did not result in an evident superiority of either agent. More research is required to identify the possible usefulness of these agents in treating hyperinflammatory diseases, such as cytokine storms, in future clinical practice.