Vinpocetine, a phosphodiesterase 1 inhibitor, mitigates atopic dermatitis-like skin inflammation.

Atopic dermatitis (AD) is the most common inflammatory pruritic skin disease worldwide, characterized by the infiltration of multiple pathogenic T lymphocytes and histological symptoms such as epidermal and dermal thickening. This study aims to investigate the effect of vinpocetine (Vinp; a phosphodiesterase 1 inhibitor) on a 1-chloro-2,4-dinitrobenzene (DNCB)-induced AD-like model. DNCB (1%) was administered on day 1 in the AD model. Subsequently, from day 14 onward, mice in each group (Vinp-treated groups: 1 mg/kg and 2 mg/kg and dexamethasone- treated group: 2 mg/kg) were administered 100 µl of a specific drug daily, whereas 0.2% DNCB was administered every other day for 30 min over 14 days. The Vinp-treated groups showed improved Eczema Area and Severity Index scores and trans-epidermal water loss, indicating the efficacy of Vinp in improving AD and enhancing skin barrier function. Histological analysis further confirmed the reduction in hyperplasia of the epidermis and the infiltration of inflammatory cells, including macrophages, eosinophils, and mast cells, with Vinp treatment. Moreover, Vinp reduced serum concentrations of IgE, interleukin (IL)-6, IL-13, and monocyte chemotactic protein-1. The mRNA levels of IL-1ß, IL-6, Thymic stromal lymphopoietin, and transforming growth factor-beta (TGF-ß) were reduced by Vinp treatment. Reduction of TGF-ß protein by Vinp in skin tissue was also observed. Collectively, our results underscore the effectiveness of Vinp in mitigating DNCB-induced AD by modulating the expression of various biomarkers. Consequently, Vinp is a promising therapeutic candidate for treating AD.

Antiinflammatory effect of the ethanolic extract of Korean native herb Potentilla rugulosa Nakai in Bisphenol-a-stimulated A549 cells.

Potentilla rugulosa Nakai (P. rugulosa) is a perennial herb in the Rosaceae family and found in the Korean mountains. Previously, our findings demonstrated that P. rugulosa contains numerous polyphenols and flavonoids exhibiting important antioxidant and anti-obesity bioactivities. Bisphenol A (BPA) is a xenoestrogen that was shown to produce pulmonary inflammation in humans. However, the mechanisms underlying BPA-induced inflammation remain to be determined. The aim of this study was to examine whether ethanolic extract of P. rugulosa exerted an inhibitory effect on BPA-induced inflammation utilizing an adenocarcinoma human alveolar basal epithelial cell line A549. The P. rugulosa extract inhibited BPA-mediated cytotoxicity by reducing levels of reactive oxygen species (ROS). Further, P. rugulosa extract suppressed the upregulation of various pro-inflammatory mediators induced by activation of the nuclear factor kappa-light-chain-enhancer of activated B cell (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. In addition, inhibition of the NF-κB and MAPK signaling pathways by P. rugulosa extract was found to occur via decrease in the transcriptional activity of NF-κB. Further, blockade of phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and stress-activated protein kinase/Jun N-terminal kinase (SAPK/JNK) was noted. Thus, our findings suggest that the ethanolic extract of P. rugulosa may act as a natural anti-inflammatory therapeutic agent.

Targeting IKKß Activity to Limit Sterile Inflammation in Acetaminophen-Induced Hepatotoxicity in Mice.

The kinase activity of inhibitory κB kinase ß (IKKß) acts as a signal transducer in the activating pathway of nuclear factor-κB (NF-κB), a master regulator of inflammation and cell death in the development of numerous hepatocellular injuries. However, the importance of IKKß activity on acetaminophen (APAP)-induced hepatotoxicity remains to be defined. Here, a derivative of caffeic acid benzylamide (CABA) inhibited the kinase activity of IKKß, as did IMD-0354 and sulfasalazine which show therapeutic efficacy against inflammatory diseases through a common mechanism: inhibiting IKKß activity. To understand the importance of IKKß activity in sterile inflammation during hepatotoxicity, C57BL/6 mice were treated with CABA, IMD-0354, or sulfasalazine after APAP overdose. These small-molecule inhibitors of IKKß activity protected the APAP-challenged mice from necrotic injury around the centrilobular zone in the liver, and rescued the mice from hepatic damage-associated lethality. From a molecular perspective, IKKß inhibitors directly interrupted sterile inflammation in the Kupffer cells of APAP-challenged mice, such as damage-associated molecular pattern (DAMP)-induced activation of NF-κB activity via IKKß, and NF-κB-regulated expression of cytokines and chemokines. However, CABA did not affect the upstream pathogenic events, including oxidative stress with glutathione depletion in hepatocytes after APAP overdose. N-acetyl cysteine (NAC), the only FDA-approved antidote against APAP overdose, replenishes cellular levels of glutathione, but its limited efficacy is concerning in late-presenting patients who have already undergone oxidative stress in the liver. Taken together, we propose a novel hypothesis that chemical inhibition of IKKß activity in sterile inflammation could mitigate APAP-induced hepatotoxicity in mice, and have the potential to complement NAC treatment in APAP overdoses.

Anti-inflammatory effects of Athyrium yokoscense extract via inhibition of the Erk1/2 and NF-κB pathways in bisphenol A-stimulated A549 cells.

Bisphenol A is an environmental endocrine disruptor that has similar functions to estrogen in humans. However, few studies have investigated pulmonary inflammation induced by BPA, and the effect of Athyrium yokoscense extract on this inflammatory response is unknown. In this study, we investigated this effect in A549 human alveolar epithelial cells. BPA at concentrations higher than 100 µM were cytotoxic to A549 cells at 24 and 48 h after treatment; however, AYE (100 µg/mL) had a protective effect against BPA-induced cytotoxicity. AYE also inhibited the generation of intracellular reactive oxygen species, expressions of cyclooxygenase-2 and extracellular signal-regulated kinase1/2 proteins, activities of phospholipase A2, COX-2, nuclear factor kappa-light-chain-enhancer of activated B cells, and proinflammatory mediators including prostaglandin E2, tumor necrosis factor-α, and interleukin-6 induced by BPA in A549 cells. This study demonstrated that BPA, which induces chronic lung disease, causes oxidative stress and inflammatory response in lung epithelial cell line, and found that AYE reduces BPA-induced oxidative stress and inflammatory response by down-regulating the Erk1/2 and NF-κB pathways.

Extract of Pinus densiflora needles suppresses acute inflammation by regulating inflammatory mediators in RAW264.7 macrophages and mice.

CONTEXT: Pinus densiflora Siebold & Zucc. (Pinaceae) needle extracts ameliorate oxidative stress, but research into their anti-inflammatory effects is limited. OBJECTIVE: To investigate antioxidant and anti-inflammatory effects of a Pinus densiflora needles (PINE) ethanol extract in vitro and in vivo. MATERIALS AND METHODS: We measured levels of reactive oxygen species (ROS), superoxide dismutase (SOD) and inflammatory mediators in lipopolysaccharide (LPS)-stimulated RAW264.7 cells at various PINE concentrations (25, 50 and 100 µg/mL; but 6.25, 12.5 and 25 µg/mL for interleukin-1ß and prostaglandin E2 (PGE2)). Thirty ICR mice were randomized to six groups: vehicle, control, PINE pre-treatment (0.1, 0.3 and 1 mg/left ear for 10 min followed by arachidonic acid treatment for 30 min) and dexamethasone. The posttreatment ear thickness and myeloperoxidase (MPO) activity were measured. RESULTS: PINE 100 µg/mL significantly decreased ROS (IC50, 70.93 µg/mL, p < 0.01), SOD (IC50, 30.99 µg/mL, p < 0.05), malondialdehyde (p < 0.01), nitric oxide (NO) (IC50, 27.44 µg/mL, p < 0.01) and tumour necrosis factor-alpha (p < 0.05) levels. Interleukin-1ß (p < 0.05) and PGE2 (p < 0.01) release decreased significantly with 25 µg/mL PINE. PINE 1 mg/ear inhibited LPS-stimulated expression of cyclooxygenase-2 and inducible NO synthase in RAW264.7 macrophages and significantly inhibited ear oedema (36.73-15.04% compared to the control, p < 0.01) and MPO activity (167.94-105.59%, p < 0.05). DISCUSSION AND CONCLUSIONS: PINE exerts antioxidant and anti-inflammatory effects by inhibiting the production of inflammatory mediators. Identified flavonoids such as taxifolin and quercetin glucoside can be attributed to effect of PINE.

Effects of vinpocetine on atopic dermatitis after administration via three different routes in HR-1 hairless mice.

This study aimed to examine the effects of vinpocetine on atopic dermatitis (AD) by administering it via oral, intraperitoneal, and topical routes to HR-1 hairless mice. AD was induced in the mice for five weeks with ovalbumin, and vinpocetine was administered twice daily through each route of administration for two weeks after the induction of AD. Vinpocetine (20, 10, and 2 mg/kg) was administered by oral, intraperitoneal, and topical routes, respectively. The administration of vinpocetine suppressed the increase in serum immunoglobulin (Ig) E and IgG1 levels and the production of interleukin (IL)-4 and IL-13-cytokines linked to T helper 2 cells in skin tissue. In addition, the invasion of inflammatory cells, including eosinophils, into the skin tissue was reduced, and changes in skin structure were also suppressed. These results show the potential for the use of vinpocetine in patients with AD and even for targeted treatment against PDE. In most of the experiments, symptom relief in the groups receiving oral and topical vinpocetine was slightly superior to that in the group receiving vinpocetine intraperitoneally. In particular, topical application of vinpocetine was found to be the most effective route when considering the dose of vinpocetine used in each route.

The effects of BRL-50481 on ovalbumin-induced asthmatic lung inflammation exacerbated by co-exposure to Asian sand dust in the murine model.

Asian sand dust (ASD), which mainly originates in China and Mongolia in the spring and blows into Korea, can exacerbate respiratory and immunological diseases. This study aims to observe effects of co-exposure to ASD on ovalbumin (OVA)-induced asthmatic lung inflammation and of treatment with a phosphodiesterase 7 (PDE7) inhibitor in a mouse model. The challenge with OVA increased airway hyperresponsiveness (AHR) and inflammatory cell infiltration into the lung tissue. Interleukin (IL)-13, tumor necrosis factor-alpha, monocyte-protein-1, mucin, and antigen-specific IgE and IgG1 production increased in mouse serum. The co-exposure of ASD significantly exacerbated these effects in this asthma model. Notably, the administration of a PDE7 inhibitor, BRL-50481 (BRL), significantly reduced AHR, infiltration of inflammatory cells into the lungs, and the levels of type 2 T helper cell-related cytokines, antigen-specific immunoglobulins, and mucin. Thus, the administration of BRL ameliorated OVA-induced allergic asthmatic responses exacerbated by co-exposure to ASD. This study suggests that PDE7 inhibition can be a therapeutic strategy for inflammatory lung diseases and asthma via the regulation of T lymphocytes and reduction of IL-13, and, consequently, mucin production.

Organic acid conjugated phenolic compounds of hardy kiwifruit (Actinidia arguta) and their NF-κB inhibitory activity.

Nine new compounds, argutinosides A-I (1-9) together with 20 known compounds (10-29), were isolated from the fruits of Actinidia arguta. Using spectral analysis, the structures of the isolated compounds were identified as 10 succinic acid derivatives, 11 quinic acid derivatives, two shikimic acid derivatives and six citric acid derivatives. The NF-κB transcriptional inhibitory activity of the compounds was evaluated using RAW 264.7 macrophages cells induced by lipopolysaccharide. Among four groups of different organic acid derivatives, the quinic acid derivatives inhibited NF-κB transcriptional activity with an IC50 value of 4.0 µM. Fruit is rich in organic acid and secondary metabolites, which differ depending on the type of fruit. Our present study showed the presence of various organic acids conjugates including nine new 2-methylsuccinic acid phenolic conjugates in kiwiberry and compared their biological activities. This will contribute to application of kiwiberry and also the diversity of different fruits.

α-Viniferin Improves Facial Hyperpigmentation via Accelerating Feedback Termination of cAMP/PKA-Signaled Phosphorylation Circuit in Facultative Melanogenesis.

Rationale: cAMP up-regulates microphthalmia-associated transcription factor subtype M (MITF-M) and tyrosinase (Tyro) in the generation of heavily pigmented melanosomes. Here, we communicate a therapeutic mechanism of hyperpigmented disorder by α-viniferin, an active constituent of Caragana sinica. Methods: We used cAMP-elevated melanocyte cultures or facial hyperpigmented patches for pigmentation assays, and applied immunoprecipitation, immunobloting, RT-PCR or reporter gene for elucidation of the antimelanogenic mechanism. Results:C. sinica or α-viniferin inhibited melanin production in α-melanocyte-stimulating hormone (α-MSH)-, histamine- or cell-permeable cAMP-activated melanocyte cultures. Moreover, topical application with C. sinica containing α-viniferin, a standard in quality control, decreased melanin index on facial melasma and freckles in patients. As a molecular basis, α-viniferin accelerated protein kinase A (PKA) inactivation via the reassociation between catalytic and regulatory subunits in cAMP-elevated melanocytes, a feedback loop in the melanogenic process. α-Viniferin resultantly inhibited cAMP/PKA-signaled phosphorylation of cAMP-responsive element-binding protein (CREB) coupled with dephosphorylation of cAMP-regulated transcriptional co-activator 1 (CRTC1), thus down-regulating expression of MITF-M or Tyro gene with decreased melanin pigmentation. Conclusion: This study assigned PKA inactivation, a feedback termination in cAMP-induced facultative melanogenesis, as a putative target of α-viniferin in the treatment of melanocyte-specific hyperpigmented disorder. Finally, C. sinica containing α-viniferin was approved as an antimelanogenic agent with topical application in skin hyperpigmentation.