Effects of different concentrations of mannitol on gene expression in Stevia rebaudiana Bertoni.

Stevia rebaudiana Bertoni is one of the most important herbal sweetener plants from Asteracea family that have a lot of Steviol glycosides. Among different methods, tissue culture is the best way with high efficiency that is useful for studying stress tolerance mechanisms to obtain drought tolerance of stevia. For this purpose, different concentrations of mannitol (0, 10, 20, 30, 40, 50 mg/l) were used as various treatments in the culture medium of stevia. According to the results, the highest level of UGT85C2 gene expression (1.181 Total lab unit) was seen in plants grown under 30 mg/l mannitol treatment and the lowest level of this gene expression (0.603 Total lab unit) was observed under 40 mg/l mannitol treatment. However, the highest level of KO gene expression (1.323 Total lab unit) was observed under 20 mg/l mannitol. It shows stevia growth is affected by osmotic stress. Water deficiency has a negative impact on Stevia. However, the expression of genes had increased by particular mannitol concentrations. Actually, stevia can survive under various abiotic stresses.

Does vitamin D deficiency contribute to higher disease activity in patients with spondyloarthritis?

INTRODUCTION: This study aimed to compare serum vitamin D levels in Spondyloarthritis (SpA) patients and control group and to evaluate the associations between vitamin D and disease activity in SpA patients. METHODOLOGY: In this study, 86 SpA patients according to the International Criteria and 117 age and sex-matched healthy controls were included. In patients, clinical examination was performed and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Bath Ankylosing Spondylitis Functional Index (BASFI) were recorded. Serum 25(OH)D3 concentration was measured using ELISA kit. RESULTS: Serum 25(OH)D3 levels in SpA patients were significantly lower than healthy controls (p < 0.001). Vitamin D deficiency and insufficiency frequency in the SpA group was significantly more than control group (p < 0.001). No significant difference was observed in the activity of SpA in different serum levels of 25(OH)D. Also, no significant correlations were observed between serum 25(OH)D3 with clinical findings as well as with BASDAI and BASFI (P > 0.05). DISCUSSION AND CONCLUSION: Although our study revealed lower serum 25(OH)D3 levels in SpA patients compared to healthy controls, there were not any significant correlations between its serum levels with severity of disease. However, correction of vitamin D status may be beneficial in controlling inflammation and disease activity.