Melatonin and REGN-CoV2 combination as a vaccine adjuvant for Omicron variant of SARS-CoV-2.

The omicron variant (B.529) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which emerged in late 2021, caused panic worldwide due to its contagiousness and multiple mutations in the spike protein compared to the Delta variant (B.617.2). There is currently no specific antiviral available to treat Coronavirus disease 2019 (COVID-19). However, studies on neutralizing monoclonal antibodies (mAb) developed to fight COVID-19 are growing and gaining traction. REGN-COV2 (Regeneron or imdevimab-casirivimab combination), which has been shown in recent studies to be less affected by Omicron's RBD (receptor binding domain) mutations among other mAb cocktails, plays an important role in adjuvant therapy against COVID-19. On the other hand, it is known that melatonin, which has antioxidant and immunomodulatory effects, can prevent a possible cytokine storm, and other severe symptoms that may develop in the event of viral invasion. Along with all these findings, we believe it is crucial to evaluate the use of melatonin with REGN-COV2, a cocktail of mAbs, as an adjuvant in the treatment and prevention of COVID-19, particularly in immunocompromised and elderly patients.

Possible cytoprotective mechanisms of oxytocin against 5-fluorouracil-induced gastrointestinal mucositis.

Gastrointestinal mucositis is a common and dose-limiting side effect characterized by ulcerative lesions in the mucosa of the digestive tract in patients receiving anticancer drugs such as 5-fluorouracil (5-FU), a potent antineoplastic drug. Several protocols have reported the efficacy of therapeutic interventions to prevent this side effect, although complete success has not yet been achieved and mucositis remains one of the most serious complications associated with 5-FU therapy. Oxytocin, a well-known antistress agent, has been reported to have comparable effects to ranitidine. Previous studies have shown that oxytocin inhibits gastric acid secretion and the expression of proinflammatory cytokines in rats. If oxytocin can reduce stress-induced ulcers via antioxidant, antiapoptotic, and anti-inflammatory pathways, then it may have a dose-dependent effect on gastrointestinal mucositis caused by 5-FU.

Antidepressant effect of Gentiana olivieri Griseb. in male rats exposed to chronic mild stress.

Background: The flowering parts of Gentiana olivieri, known as 'Afat' in the southeastern Anatolia region of Turkey, are used as a tonic, an appetizer, and for the treatment of several mental disorders, including depression. The purpose of this study is to investigate the antidepressant effect of G. olivieri ethanol extract (GOEE) in a chronic mild stress-induced rat model, which was used to mimic a depressive state in humans, and to compare the effect with that of imipramine.Methods: Male Sprague-Dawley rats were randomly divided into six groups: control, stress, treated with imipramine (positive control) and treated with GOEE at three different (200, 500, 1000 mg/kg) doses groups. The rats in all groups, except the control group, were exposed to chronic mild stress. At the end of the 3-week experimental period, biochemical and behavioral parameters were examined.Results: The results showed that treatment with GOEE or imipramine significantly improved rats' sucrose consumption which was diminished by chronic mild stress, restored serum levels of corticosterone and proinflammatory cytokines (interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α)), prevented the increase of liver index of rats. Moreover, in the hippocampus tissue, decreased serotonin and noradrenaline levels were significantly increased by treatment with GOEE or imipramine, and antioxidant parameters (thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), and glutathione (GSH)) were significantly improved by treatment with GOEE though not with imipramine.Conclusion: The data demonstrate that G. olivieri may exert its antidepressant activity by improving monoaminergic system disorders, and by favorably affecting the antioxidant, inflammatory and the endocrine mechanisms.