Silk fibroin hydrogel containing Sesbania sesban L. extract for rheumatoid arthritis treatment.

PURPOSE: Rheumatoid arthritis, a chronic and progressive inflammation condition in the joints, has significantly reduced the patient quality of life and life expectancy. Crucially, there is no complete therapy for this disease, and the current treatments possess numerous side effects. Thus, novel therapeutic approach is necessary. To that end, this study developed novel silk fibroin in-situ hydrogel containing Sesbania sesban L. extract, a plant with high anti-inflammatory actions that are beneficial for rheumatoid arthritis treatments. METHODS: The hydrogels were manufactured using simple method of spontaneous gelation at different temperature. The gel properties of morphology, gelation time, viscosity, gel strength, stability, drug loading capacity, drug release rate, and in-vitro anti-inflammatory activity were investigated with appropriate methods. RESULTS: The optimal formulation had highly porous structure, with a gelation time of 0.5 h at room temperature and bodily temperature of 37 °C, a viscosity of 2530 ± 50 cP, a gel strength of 1880.14 ± 35.10 g, and a physical stability of >6 months. Moreover, the hydrogel contained the Sesbania sesban L. leaf extract with a total phenolic content of 92.8 ± 8.30 mg GAE/g, and sustained the release rate for >20 days, followed the Higuchi model. Regarding the in-vitro activities, all formulations were nontoxic to the RAW 264.7 cell line and demonstrated comparable anti-inflammatory activity to the free extract, in terms of the NO reduction levels. CONCLUSION: Conclusively, the systems possessed potential properties to be further investigated to become a prospective rheumatoid arthritis treatment.

Effects of Launaea sarmentosa Extract on Lipopolysaccharide-Induced Inflammation via Suppression of NF-κB/MAPK Signaling and Nrf2 Activation.

Launaea sarmentosa has been extensively used as a nutrient herb in traditional Vietnamese remedies for the treatment of various diseases, especially inflammatory diseases. However, no detailed research has been conducted examining the molecular mechanisms involved in the suppression of inflammatory response. Here, we studied the effects of L. sarmentosa methanol extract on lipopolysaccharide (LPS)-induced inflammation using RAW 264.7 macrophages. The extract demonstrated potent antioxidant activity owing to the presence of polyphenolic and flavonoid components. Pretreatment with the extract inhibited LPS-mediated secretion of nitric oxide, reactive oxygen species, and tumor necrosis factor-α as well as the expression of inflammatory cytokines. Furthermore, the activation of the nuclear factor-kappa B pathway and phosphoinositide-3-kinase/protein kinase B pathways was blocked by the extract by inhibiting Akt phosphorylation. Additionally, the mitogen-activated protein kinase pathway was suppressed, and endoplasmic reticulum stress was attenuated. Furthermore, the extract promoted the activity of nuclear factor erythroid-2-related factor 2 resulting in the up-regulation of heme oxygenase-1 pathway, leading to the suppression of oxidative stress and inflammatory response. Taken together, the results indicate that L. sarmentosa exhibits anti-inflammatory effects, and hence, can be further developed as a novel drug for the treatment of diseases associated with excessive inflammation.

Anti-Inflammatory Effects of Lasia spinosa Leaf Extract in Lipopolysaccharide-Induced RAW 264.7 Macrophages.

Lasia spinosa (L.) Thwaites was used as a traditional medicine to treat many inflammatory diseases for centuries. However, its effects on the inflammatory response are not yet characterized. In this study, we investigated the anti-inflammatory activities of L. spinosa leaf extract in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. We found that ethanol extracts of L. spinosa leaves showed anti-oxidant activity due to the presence of high levels of polyphenolic compounds. Treatment with the leaf extract significantly repressed the production of inflammatory mediators such as nitric oxide and reactive oxygen species and the expression of pro-inflammatory cytokines in the LPS-stimulated RAW 264.7 cells. Moreover, L. spinosa leaf extract treatment prevented activation of the nuclear factor-kappa B pathway by inhibiting nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) degradation. Furthermore, the mitogen-activated kinase and phosphoinositide-3-kinase/protein kinase B (PI3K/Akt) pathways were suppressed upon treatment with the leaf extract. In addition to suppressing inflammatory factors, the extract also activated the nuclear factor erythroid 2-related factor 2/heme-oxygenase-1 pathway. We propose that L. spinosa leaf extract has the potential as an effective therapeutic agent for alleviating oxidative stress and excessive inflammation.