Preparation, characterization and bioactivities of selenized polysaccharides from Lonicera caerulea L. fruits.

Native polysaccharide was obtained from Lonicera caerulea L. fruits (PLP). Two selenized polysaccharides (PSLP-1 and PSLP-2) were synthesized by the microwave-assisted HNO3-Na2SeO3 method, where the selenium (Se) contents were 228 ± 24 and 353 ± 36 µg/g, respectively. The molecular weights of PLP, PSLP-1, and PSLP-2 were 5.9 × 104, 5.6 × 104, and 5.1 × 104 kDa, respectively. PSLP-1 and PSLP-2 contained the same type of monosaccharides as PLP but with different molar ratios. The main chain structure of the native polysaccharide was not changed after selenization. PLP, PSLP-1, and PSLP-2 contained the same six types of glycosidic bonds. Bioactivity assays revealed that the two selenized polysaccharides possessed better antioxidant activities than PLP, but their bile acid-binding abilities and inhibitory activities on acetylcholinesterase (AChE) had weakened. In summary, PLP, PSLP-1, and PSLP-2 may be promising Se supplements in functional foods and inhibitors for the treatment of AChE.

Activity of terpenes derived from essential oils against Sarcoptes scabiei eggs.

BACKGROUND: The limited ovicidal activity of currently available acaricides is a significant obstacle to efficacious scabies treatment. Several essential oils or their respective components have proved to be active against the eggs of arthropods, mainly lice and ticks. Information on the activity of these oils and/or components against the eggs of mites remains very limited. The aim of this study was to assess the activity of six terpenes (carvacrol, eugenol, geraniol, citral, terpinen-4-ol and linalool) commonly found in essential oils against the eggs of Sarcoptes scabiei. METHODS: Sarcoptes eggs were exposed to paraffin oil containing 1, 2.5, or 5% of each terpene tested. After a 12-h exposure period, the eggs were washed and placed in paraffin oil for hatching. Embryonic development following treatment was assessed every day to determine the stage of developmental arrest. RESULTS: The median effective concentration to obtain 50% egg mortality (EC50) was 0.5, 0.9, 2.0, 4.8, 5.1 and 9.8% for carvacrol, eugenol, geraniol, citral, terpinen-4-ol and linalool, respectively. The microscopic images of eggs after each treatment indicated that these six terpenes may act by penetrating through the aeropyles on the egg surface. CONCLUSIONS: In conclusion, carvacrol, eugenol and geraniol possess significant ovicidal activities, which should be considered as promising ovicidal agents for the treatment of scabies.

Yishen-tongbi decoction inhibits excessive activation of B cells by activating the FcγRIIb/Lyn/SHP-1 pathway and attenuates the inflammatory response in CIA rats.

Rheumatoid arthritis (RA) is a chronic autoimmune disease. Strong evidence supports that excessive activation of B cells plays a critical role in the pathogenesis of RA. Fc gamma receptor b (FcγRIIb) is the B cell inhibitory receptor and inhibits BCR (B cell receptor) signalling in part by selectively dephosphorylating CD19 which is considered a co-receptor for BCR and is essential for B cell activation. Our previous study demonstrated that a FcγRIIb I232T polymorphism presented a strong genetic link to RA and may lead to the excessive activation of B cells. Therefore, novel therapeutic strategies and drugs that can effectively inhibit the excessive activation of B cells by regulating the FcγRIIb are necessary for the treatment of RA. Therefore, we used Burkitt's lymphoma ST486 human B cells (lacking endogenous FcγRIIb) transfected with the 232Thr loss-of-function mutant to construct a FcγRIIb mutant cell line (ST486), and we demonstrated that YSTB treatment not only reduced proliferation and promoted apoptosis in ST486 cells but also did so in a dose-dependent manner. Furthermore, the intracellular Ca2+ flux of ST486 cells was decreased after treatment with YSTB, inhibiting the excessive activation of ST486 cells, and these effects correlated with the CD19/FcγRIIb-Lyn-SHP-1 pathways. Our data showed that YSTB treatment inhibited the expression of phosphorylated CD19 and upregulated the protein expression of FcγRIIb, Lyn, and SHP-1. Additionally, the CIA model was established to explore the anti-inflammatory and inhibitory effects of YSTB on bone destruction, and we found that YSTB decreased the paw oedema and arthritis index (AI) in CIA rats. It is worth mentioning that YSTB clearly decreased the AI earlier than methotrexate (MTX) (day 10 vs 16). Moreover, synovial hyperplasia, inflammatory cell infiltration and cartilage surface erosion in CIA rats were noticeably reduced after treatment with YSTB as evidenced by histopathological examination. Finally, we found that YSTB treatment suppressed bone erosion and joint space score (JNS) in CIA rats as evidenced by radiographic assessment. In summary, these data suggest that YSTB has great therapeutic potential for RA treatment.

Lemongrass (Cymbopogon citratus) oil: A promising miticidal and ovicidal agent against Sarcoptes scabiei.

BACKGROUND: Essential oils may represent an alternative strategy for controlling scabies, a neglected tropical disease caused by the infestation of mite from the species Sarcoptes scabiei. Lemongrass (Cymbopogen citratus) oil is reported to possess pharmacological properties including antiparasitc, antioxidant, antimicrobial and anti-inflammatory. The aim of the present study was to assess the potential efficacy of lemongrass oil against the mites and eggs of Sarcoptes scabiei. METHODOLOGY/PRINCIPAL FINDINGS: Mass spectrometry analysis confirmed that the main component presented in lemongrass oil was citral. Lemongrass oil at concentrations of 10% and 5% killed all Sarcoptes mites within 10 and 25 min, respectively. The median lethal concentration value was 1.37%, 1.08%, 0.91%, 0.64%, and 0.48% at 1, 3, 6, 12, and 24 h, respectively. Lemongrass oil at all concentrations (10%, 5%, 1%, 0.5%, 0.1%) was able to significantly decrease the hatching rate of Sarcoptes eggs. CONCLUSIONS/SIGNIFICANCE: Lemongrass oil should be considered as a promising miticidal and ovicidal agent for scabies control.

Evaluating the therapeutic efficacy of the Chinese herbal medicine Yishen Tongbi decoction in patients with active rheumatoid arthritis: protocol for a randomized, controlled, noninferiority trial.

BACKGROUND: Rheumatoid arthritis (RA) is a common chronic autoimmune disease that seriously affects the quality of life of patients because of damage to joints. Presently, RA is mainly treated with disease-modifying antirheumatic drugs (DMARDs) or biological agents; however, they offer limited efficacy in some patients. Therefore, additional therapeutic strategies need to be developed. Yishen Tongbi decoction is a traditional Chinese medicine formulation widely used to treat RA in China. However, currently, there is insufficient evidence to recommend its use for the treatment of RA. Therefore, we aim to verify the efficacy of Yishen Tongbi decoction to treat RA by a noninferiority trial, and to provide a basis for its use with a full-scale clinical trial. METHODS/DESIGN: One hundred eligible patients with RA will be randomized into two groups of 50 patients. One group will receive Yishen Tongbi decoction and placebo replacing methotrexate (MTX), while the other group will receive MTX and placebo replacing Yishen Tongbi decoction. Patient's whose visual analogue scale score for pain is greater than 40 mm will be administered nonsteroidal anti-inflammatory drugs (such as enteric-coated diclofenac sodium, 25 mg three times a day); administration of all medications will be recorded. The clinical indicators of patients and their disease activity will be assessed at baseline and at 4, 12 and 24 weeks after treatment initiation. The primary outcome of efficacy will be the proportion of patients who demonstrate a favourable response based on their Clinical Disease Activity Index score at 24 weeks after treatment. All adverse events will be reported. DISCUSSION: Traditional Chinese medicine theory and modern western medicine research have identified the efficacy of Yishen Tongbi decoction to treat RA. Previous clinical observation and efficacy trials of Yishen Tongbi decoction in animal models for the treatment of RA has demonstrated significant effect. Because of the potential benefits of Yishen Tongbi decoction in the treatment of patients with RA, we designed this double-blind, prospective, randomized controlled trial; the results and conclusions of the trail will be published after the completion of the study. TRIAL REGISTRATION: Chinese Clinical Trials Registry, ChiCTR1900024902. Registered on 3 August 2019.