Efficacy of Qingpeng ointment (a Tibetan medicine) for acute gouty arthritis: a multi-center, randomized, double-blind, placebo-controlled trial.

BACKGROUND: This study aims to assess the efficacy and safety of Qingpeng ointment (QPO), a Tibetan medicine for alleviating symptoms in individuals with acute gouty arthritis (AGA). METHODS: This study was a randomized, double-blind, placebo-controlled trial that involved individuals with AGA whose joint pain, as measured on a visual analog scale (VAS) from 0 to 10, was equal to or greater than 3. The participants were randomly assigned to either the QPO or the placebo group and received their respective treatments twice daily for seven consecutive days. In case of intolerable pain, the participants were allowed to use diclofenac sodium sustained-release tablets as a rescue medicine. The primary outcomes measured were joint pain and swelling, while the secondary outcomes included joint mobility, redness, serum uric acid levels, C-reactive protein levels, and the amount of remaining rescue medicine. Any adverse events that occurred during the trial were also recorded. RESULTS: A total of 203 cases were divided into two groups, with balanced baselines: 102 in the QPO group and 101 in the placebo group. For joint pain, differences between the groups were notable in the VAS scores [1.75 (0, 3.00) versus 2.00 (1.00, 3.50); P = 0.038], changes in VAS [5.00 (3.00, 6.00) versus 4.00 (2.00, 6.00); P = 0.036], and disappearance rate [26.47% compared to 15.84%; P = 0.046] after treatment. Concerning joint swelling, significant between-group differences were observed in the VAS scores [1.00 (0, 2.30) versus 2.00 (0.70, 3.00); P = 0.032] and disappearance rate [33.33% compared to 21.78%; P = 0.046] at treatment completion. The QPO group exhibited a statistically significant mobility improvement compared to the placebo group (P = 0.004). No significant differences were found in other secondary outcomes. Five patients, four from the QPO group and one from the other, encountered mild adverse events, primarily skin irritation. All of these cases were resolved after dosage reduction or discontinuation of the medication. CONCLUSIONS: Compared to the placebo, QPO exhibits positive effects on AGA by alleviating pain, reducing swelling, and enhancing joint mobility, without causing significant adverse effects. TRIAL REGISTRATION: ISRCTN34355813. Registered on 25/01/2021.

The inhibition of advanced glycation end-products by five fractions and three main flavonoids from Camellia nitidissima Chi flowers.

Camellia nitidissima Chi (CNC), belonging to Camellia genus (Theaceae family), is a medicinal and edible plant in China. Among the whole plant, the CNC flowers are especially precious, but the biological activities and the compositions of the CNC flowers are unknown. In this study, inhibiting effects on the formation of advanced glycation end-products (AGEs) of five CNC flowers fractions and three isolated compounds were investigated, these three compounds are two flavonoid glycosides and one flavanol, namely kaempferol 3-O-[2,3,4-Tri-O-acetyl-α-L-rhamnopyranosyl-(1→3)-2,4-di-O-acetyl-α-L-rhamnopyranosyl-(1→6)]-ß-D-glucopyranoside, kaempferol 3-O-[2,3,4-Tri-O-acetyl-α-L-rhamnopyranosyl-(1→3)-4-O-acetyl-α-L-rhamnopyranosyl-(1→6)]-ß-D-glucopyranoside and catechin. Among these five fractions, the ethyl acetate fraction showed the highest total phenolic contents and inhibiting effects on AGE formation. Bovine serum albumin (BSA)-glucose and BSA-methylglyoxal assay showed that the ethyl acetate fraction inhibited AGE formation by 74.49% and 34.3% at 1 mg/mL, respectively. As the main components, these three compounds also showed remarkable inhibiting effects on AGE formation by scavenging methylglyoxal, next two catechin-carbonyl adducts were identified using HPLC-ESI-MS/MS. The results showed that the CNC flowers had remarkable inhibiting effects on the formation of AGEs. The primary structure-activity relationship showed (1) the glycosides could reduce the inhibiting effects compared to kaempferol and (2) the acetyl at position 2‴ in compound 1 had no remarkable influence of the inhibiting effects on AGE formation compared to compound 2.