Highlights• The majority of cases were in the age group of 50 to 60 years of old.•A total of 2964 cases of COVID-19 were investigated. J o u r n a l P r e -p r o o fThe datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Treatment of osteoarthritis (OA) is challenging owing to the inefficacy and long-term adverse events of currently available medications including non-steroidal anti-inflammatory drugs. Curcuminoids are polyphenolic phytochemicals with established anti-inflammatory properties and protective effects on chondrocytes. The aim of this study is to investigate the clinical efficacy of curcuminoids in patients suffering from knee OA. A pilot randomized double-blind placebo-control parallel-group clinical trial was conducted among patients with mild-to-moderate knee OA. Patients were assigned to curcuminoids (1500 mg/day in 3 divided doses; n = 19) or matched placebo (n = 21) for 6 weeks. Efficacy measures were changes in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), visual analogue scale (VAS) and Lequesne's pain functional index (LPFI) scores during the study. There was no significant difference in age, gender, body mass index, and VAS, WOMAC and LPFI scores between the study groups at baseline (p > 0.05). Treatment with curcuminoids was associated with significantly greater reductions in WOMAC (p = 0.001), VAS (p < 0.001) and LPFI (p = 0.013) scores compared with placebo. With respect to WOMAC subscales, there were significant improvements in the pain and physical function scores (p < 0.001) but not stiffness score (p > 0.05). There was no considerable adverse effect in both groups. To conclude, curcuminoids represent an effective and safe alternative treatment for OA.

Oxidative stress is implicated in the pathogenesis of osteoarthritis. Curcuminoids are natural polyphenols with strong antioxidant capacity and may thus be helpful in the treatment of osteoarthritis. The present randomized double-blind placebo-controlled trial investigated the efficacy of curcuminoids in reducing systemic oxidative burden in patients suffering from knee osteoarthritis. Forty patients with mild-to-moderate primary knee osteoarthritis were given curcuminoid capsules (1500 mg/day in 3 divided doses; n = 19) or matched placebo capsules (n = 21) for a period of 6 weeks. Curcuminoids were co-administered with piperine (15 mg/day) in order to improve the bioavailability. Serum activities of superoxide dismutase (SOD) and concentrations of reduced glutathione (GSH) and malonedialdehyde (MDA) were determined spectrophotometrically at baseline and at the end of the treatment period in both groups. Serum activities of SOD as well as GSH and MDA concentrations were comparable between the study groups at baseline (p > 0.05). There was a significant elevation in serum SOD activities (mean change: 2.94 ± 3.73 vs. -0.38 ± 1.33; p < 0.001), a borderline significant elevation in GSH concentrations (mean change: 1.39 ± 2.78 vs. -0.02 ± 1.62; p = 0.064) and a significant reduction in MDA concentrations (mean change: -5.26 ± 4.46 vs. -2.49 ± 3.81; p = 0.044) in the curcuminoids compared with the placebo group. Changes in serum activities of SOD and concentrations of GSH and MDA during the course of trial were significantly correlated. Short-term supplementation with curcuminoids attenuates systemic oxidative stress in patients with osteoarthritis. These antioxidant effects may account for the reported therapeutic effects of curcuminoids in relieving osteoarthritis symptoms.

Background : Melatonin has been known as an anti-inflammatory agent and immune modulator that may address progressive pathophysiology of coronavirus disease 2019 (COVID-19).Aim of the study. To evaluate the clinical efficacy of adjuvant, use of melatonin in patients with COVID-19. Methods : This single-center, double-blind, randomized clinical trial included 74 hospitalized patients with confirmed mild to moderate COVID-19 at Baqiyatallah Hospital in Tehran, Iran, from April 25, 2020–June 5, 2020. Patients were randomly assigned in a 1:1 ratio to receive standard of care and standard of care plus melatonin at a dose of 3 mg three times daily for 14 d. Clinical characteristics, laboratory, and radiological findings were assessed and compared between two study groups at baseline and post-intervention. Safety and clinical outcomes were followed up for four weeks. Results : A total of 24 patients in the intervention group and 20 patients in the control group completed the treatment. Compared with the control group, the clinical symptoms such as cough, dyspnea, and fatigue, as well as the level of CRP and the pulmonary involvement in the intervention group had significantly improved (p <0.05). The mean time of hospital discharge of patients and return to baseline health was significantly shorter in the intervention group compared to the control group (p <0.05). No deaths and adverse events were observed in both groups. Conclusions : Adjuvant use of melatonin has a potential to improve clinical symptoms of COVID-19 patients and contribute to a faster return of patients to baseline health.

Significant improvement in clinical symptoms of OA in curcuminoid-treated subjects cannot be attributed to the systemic anti-inflammatory effects of these phytochemicals.