Camellia sinensis L. alleviates OVA-induced allergic asthma through NF-κB and MMP-9 pathways.

Allergic asthma, a type of chronic airway inflammation, is a global health concern because of its increasing incidence and recurrence rates. Camellia sinensis L. yields a variety type of teas, which are also used as medicinal plants in East Asia and are known to have antioxidant, anti-inflammatory, and immune-potentiating properties. Here, we examined the constituents of C. sinensis L. extract (CSE) and evaluated the protective effects of CSE on allergic asthma by elucidating the underlying mechanism. To induce allergic asthma, we injected the sensitization solution (mixture of ovalbumin (OVA) and aluminum hydroxide) into mice intraperitoneally on days 0 and 14. Then, the mice were exposed to 1% OVA by a nebulizer on days 21 to 23, while intragastric administration of CSE (30 and 100 mg/kg) was performed each day on days 18 to 23. We detected five compounds in CSE, including (-)-epigallocatechin, caffeine, (-)-epicatechin, (-)-epigallocatechin gallate, and (-)-epicatechin gallate. Treatment with CSE remarkably decreased the airway hyperresponsiveness, OVA-specific immunoglobulin E level, and inflammatory cell and cytokine levels of mice, with a decrease in inflammatory cell infiltration and mucus production in lung tissue. Treatment with CSE also decreased the phosphorylation of nuclear factor-κB (NF-κB) and the expression of matrix-metalloproteinase (MMP)-9 in asthmatic mice. Our results demonstrated that CSE reduced allergic airway inflammation caused by OVA through inhibition of phosphorylated NF-κB and MMP-9 expression.

Achyranthis radix Extract Enhances Antioxidant Effect of Placenta-Derived Mesenchymal Stem Cell on Injured Human Ocular Cells.

Age-related ocular diseases such as age-related macular degeneration, glaucoma, and diabetic retinopathy are major causes of irreversible vision impairment in the elderly. Conventional treatments focus on symptom relief and disease slowdown, often involving surgery, but fall short of providing a cure, leading to substantial vision loss. Regenerative medicine, particularly mesenchymal stem cells (MSCs), holds promise for ocular disease treatment. This study investigates the synergistic potential of combining placenta-derived MSCs (PD-MSCs) with Achyranthis radix extract (ARE) from Achyranthes japonica to enhance therapeutic outcomes. In a 24-h treatment, ARE significantly increased the proliferative capacity of PD-MSCs and delayed their senescence (* p < 0.05). ARE also enhanced antioxidant capabilities and increased the expression of regeneration-associated genes in an in vitro injured model using chemical damages on human retinal pigment epithelial cell line (ARPE-19) (* p < 0.05). These results suggest that ARE-primed PD-MSC have the capability to enhance the activation of genes associated with regeneration in the injured eye via increasing antioxidant properties. Taken together, these findings support the conclusion that ARE-primed PD-MSC may serve as an enhanced source for stem cell-based therapy in ocular diseases.

The Inhibition Activity of Natural Methoxyflavonoid from Inula britannica on Soluble Epoxide Hydrolase and NO Production in RAW264.7 Cells.

Soluble epoxide hydrolase (sEH) is an enzyme targeted for the treatment of inflammation and cardiovascular diseases. Activated inflammatory cells produce nitric oxide (NO), which induces oxidative stress and exacerbates inflammation. We identify an inhibitor able to suppress sEH and thus NO production. Five flavonoids 1-5 isolated from Inula britannica flowers were evaluated for their abilities to inhibit sEH with IC50 values of 12.1 ± 0.1 to 62.8 ± 1.8 µM and for their effects on enzyme kinetics. A simulation study using computational chemistry was conducted as well. Furthermore, five inhibitors (1-5) were confirmed to suppress NO levels at 10 µM. The results showed that flavonoids 1-5 exhibited inhibitory activity in all tests, with compound 3 exhibiting the most significant efficacy. Thus, in the development of anti-inflammatory inhibitors, compound 3 is a promising natural candidate.