Differences in anti-inflammatory effect of immature and mature of Rubus coreanus fruits on LPS-induced RAW 264.7 macrophages via NF-κB signal pathways

Rubus urticifolius Compounds with Antioxidant Activity, and Inhibition Potential against Tyrosinase, Melanin, Hyaluronidase, Elastase, and Collagenase

In our study, using chromatographic techniques, we isolated three bioactive compounds, which were structurally elucidated as (E)-2-(3-(3,4-dimethoxyphenyl)acrylamido)-N-methylbenzamide (1), 4-Hydroxyquinoline-2-carboxylic acid (2), and (E)-2-Cyano-3-(4-hydroxyphenyl)acrylic acid (3), using spectroscopic methods. The anti-melanogenic, anti-inflammatory, antioxidant, and anti-aging properties were evaluated in vitro by measuring the activity of pharmacological targets including tyrosinase, melanin, NF-κB, hyaluronidase, elastase, collagenase, and Nrf2. Our results show that compound 1 is the most active with IC50 values of 14.19 μM (tyrosinase inhibition), 22.24 μM (melanin inhibition), 9.82-12.72 μM (NF-κB inhibition), 79.71 μM (hyaluronidase inhibition), 80.13 μM (elastase inhibition), 76.59 μM (collagenase inhibition), and 116-385 nM (Nrf2 activation) in the THP-1, HEK001, WS1, and HMCB cells. These findings underscore the promising profiles of the aqueous extract of R. urticifolius at safe cytotoxic concentrations. Additionally, we report, for the first time, the isolation and characterisation of these nitrogenous compounds in the R. urticifolius species. Finally, compound 1, isolated from R. urticifolius, is a promising candidate for the development of more effective and safer compounds for diseases related to skin pigmentation, protection against inflammation, and oxidative stress.

Effect of Immature Rubus occidentalis on Postoperative Pain in a Rat Model

Background and Objectives: This study aimed to identify the analgesic properties of immature Rubus occidentalis extract (iROE) using a postoperative-pain rat model. We also aimed to compare the analgesic effects of iROE to those of mature R. occidentalis extract (mROE) and examine the proinflammatory cytokine response and associated underlying mechanisms. Materials and Methods: In adult male Sprague Dawley rats, acute postoperative pain was induced through plantar hind-paw incisions. After the plantar incisions were made, the rats were intraperitoneally administered with normal saline or various doses of iROE and mROE to investigate and compare the analgesic effects of iROE and mROE. The mechanisms underlying iROE-induced analgesia were investigated via post-incisional administration of yohimbine, dexmedetomidine, prazosin, naloxone, atropine, or mecamylamine, followed by iROE. Mechanical withdrawal threshold (MWT) evaluations with von Frey filaments were carried out at different time points. Serum levels of tumor necrosis factor α, interleukin (IL)-1β, and IL-6 were measured to assess inflammatory responses. Multivariate analysis of variance (MANOVA) and linear mixed-effects model (LMEM) analysis were used to analyze the analgesic effect data. Results: The MWTs demonstrated significant increases in iROE in a dose-dependent manner up to 2 h after the plantar incisions were made. An LMEM analysis demonstrated that iROE yielded a significantly greater analgesic effect than mROE, but there was no significant difference between the two according to MANOVA. Dexmedetomidine enhanced the MWT-confirmed iROE response, while yohimbine and naloxone diminished it. Administration of iROE significantly attenuated the post-incisional increases in serum IL-1β and IL-6 levels. Conclusions: The iROE demonstrated analgesic and anti-inflammatory effects in a rat model of incisional pain, which were more pronounced than those associated with mROE. The analgesic activity of iROE may be associated with α₂-adrenergic and opioid receptors.

Effectiveness of maturity of Rubus occidentalis on hyperalgesia induced by acidic saline injection in rats

Background

Rubus occidentalis, also known as black raspberry, contains several bioactive components that vary depending on the maturity of the fruit. The goal of this study was to evaluate the efficacy of immature Rubus occidentalis extract(iROE) on acid-induced hyperalgesia, investigate the mechanism involved, and compare the antihyperalgesic effect of immature and mature ROEs.

Methods

In adult male Sprague-Dawley rats, chronic muscle pain was induced via two injections of acidic saline into one gastrocnemius muscle. To evaluate the dose response, the rats were injected intraperitoneally with 0.9% saline or iROE (10, 30, 100, or 300 mg/kg) following hyperalgesia development. To evaluate the mechanism underlying iROE-induced analgesia, the rats were injected intraperitoneally with saline, yohimbine 2 mg/kg, dexmedetomidine 50 μg/kg, prazosin 1 mg/kg, atropine 5 mg/kg, mecamylamine 1 mg/kg, or naloxone 5 mg/kg 24 h after hyperalgesia development, followed by iROE 300 mg/kg administration. To compare immature versus mature ROE, the rats were injected with mature ROE 300 mg/kg and immature ROE 300 mg/kg after hyperalgesia development. For all experiments, the mechanical withdrawal threshold(MWT) was evaluated using von Frey filaments before the first acidic saline injection, 24 h after the second injection, and at various time points after drug administration. Data were analysed using multivariate analysis of variance(MANOVA) and the linear mixed-effects model(LMEM). We compared the MWT at each time point using analysis of variance with the Bonferroni correction.

Results

The iROE 300 mg/kg injection resulted in a significant increase in MWT compared with the control, iROE 30 mg/kg, and iROE 100 mg/kg injections at ipsilateral and contralateral sites. The iROE injection together with yohimbine, mecamylamine, or naloxone significantly decreased the MWT compared with iROE alone, whereas ROE together with dexmedetomidine significantly increased the MWT. According to MANOVA, the effects of immature and mature ROEs were not significantly different; however, the LMEM presented a significant difference between the two groups.

Conclusions

Immature R. occidentalis showed antihyperalgesic activity against acid-induced chronic muscle pain, which may be mediated by the α2-adrenergic, nicotinic cholinergic, and opioid receptors. The iROE displayed superior tendency regarding analgesic effect compared to mature ROE.

Water Extract of Rubus coreanus Prevents Inflammatory Skin Diseases In Vitro Models

Atopic dermatitis (AD) is a chronic inflammatory skin disease caused by immune hypersensitivity reaction. The cause of AD is unclear, but its symptoms have a negative effect on quality of life; various treatment methods to alleviate these symptoms are underway. In the present study, we aimed to evaluate in vitro antioxidant and anti-inflammatory effects of Rubus coreanus water extract (RCW) on AD. Total phenolic compounds and flavonoid content of RCW were 4242.40 ± 54.84 mg GAE/g RCE and 1010.99 ± 14.75 mg CE/g RCW, respectively. RCW reduced intracellular reactive oxygen species level and increased the action of antioxidant enzymes, such as catalase, superoxide dismutase, and glutathione peroxidase in tumor necrosis factor-α (TNF-α)/interferon-γ (IFN-γ)-stimulated HaCaT cells. Moreover, mRNA expression of the pro-inflammatory cytokines, including TNF-α, interleukin-1β, and interleukin-6, was downregulated by RCW in the TNF-α/IFN-γ-stimulated cells. The levels of inflammatory chemokines (thymus- and activation-regulated chemokine; eotaxin; macrophage-derived chemokine; regulated on activation, normal T-cell expressed and secreted; and granulocyte-macrophage colony-stimulating factor) and intercellular adhesion molecule-1 were decreased in the TNF-α/IFN-γ-stimulated HaCaT cells after RCW treatment. Additionally, the mRNA expression levels of filaggrin and involucrin, proteins that form the skin, were increased by RCW. Furthermore, RCW inhibited the nuclear factor kappa-light-chain-enhancer of the activated B cells pathway in the TNF-α/IFN-γ-stimulated HaCaT cells. Collectively, the present investigation indicates that RCW is a potent substance that inhibits AD.

Heat Treatment Improves UV Photoprotective Effects of Licorice in Human Dermal Fibroblasts

External stimulation of the skin by ultraviolet B (UVB) radiation induces oxidative stress or inflammation, causing skin aging and skin cancer. Glycyrrhiza uralensis (licorice) has been used as a medicinal plant for its antioxidant, anti-inflammatory, antiviral, antimicrobial, anticarcinogenic, and hepatoprotective properties. The present study analyzed the effects of thermal processing on the bioactivities of licorice. Heat-treated licorice (HL) extracts had better antioxidant and anti-inflammatory activities than non-treated licorice (NL) extract. HL extracts also had higher total phenol contents than NL extract. In particular, contents of isoliquiritigenin, an antioxidant and anti-inflammatory substance of licorice, increased in proportion to the skin-protection effects of HL extracts. Heat treatment increased the contents of phenolic compounds such as isoliquiritigenin in licorice extract, which improved the UV photoprotective effect of licorice in human dermal fibroblasts.

Rubi Fructus Water Extract Alleviates LPS-Stimulated Macrophage Activation via an ER Stress-Induced Calcium/CHOP Signaling Pathway

Despite the availability of antibiotics and vaccines, many intractable infectious diseases still threaten human health across the globe. Uncontrolled infections can lead to systemic inflammatory response syndrome and the excessive production of inflammatory cytokines, known as a cytokine storm. As cytokines also play necessary and positive roles in fighting infections, it is important to identify nontoxic and anti-inflammatory natural products that can modulate cytokine production caused by infections. Rubi Fructus, the unripe fruits of Rubus coreanus Miquel, are known to possess antioxidative properties. In this study, the effect of the water extract of Rubi Fructus (RF) on the lipopolysaccharide (LPS)-induced inflammatory response in RAW 264.7 macrophages was investigated using biochemical and cell biology techniques. Our data indicated that RF inhibits p38 phosphorylation, intracellular calcium release, and the production of nitric oxide (NO), interleukin (IL)-6, monocyte chemotactic activating factor (MCP)-1, tumor necrosis factor (TNF)-α, leukemia inhibitory factor (LIF), lipopolysaccharide-induced CXC chemokine (LIX), granulocyte-colony stimulating factor (G-CSF), granulocyte macrophage colony-stimulating factor (GM-CSF), vascular endothelial growth factor (VEGF), macrophage colony-stimulating factor (M-CSF), macrophage inflammatory protein (MIP)-1α, MIP-1β, MIP-2, and regulated on activation, normal T cell expressed and secreted (RANTES) in LPS-treated macrophages. In addition, we observed decreasing mRNA expression of Chop, Camk2a, Stat1, Stat3, Jak2, Fas, c-Jun, c-Fos, Nos2, and Ptgs2 without cytotoxic effects. We concluded that RF demonstrated immunoregulatory activity on LPS-stimulated macrophages via an endoplasmic reticulum (ER) stress-induced calcium/CCAAT-enhancer-binding protein homologous protein (CHOP) pathway and the Janus kinase (JAK)/signal transducers and activators of transcription (STAT) pathway.

4'-O-β-D-glucosyl-5-O-methylvisamminol ameliorates imiquimod-induced psoriasis-like dermatitis and inhibits inflammatory cytokines production by suppressing the NF-κB and MAPK signaling pathways

Psoriasis is a chronic inflammatory skin disorder in humans, and the inflammatory reaction plays an important role in development and onset of psoriasis. 4'-O-β-D-glucosyl-5-O-methylvisamminol (4GMV) is one of the major active chromones isolated from Saposhnikoviae divaricata (Turcz.) Schischk, which has been reported to exhibit excellent anti-inflammatory activities. However, the possible therapeutic effect on psoriasis and underlying mechanism has not been reported. Thus, the aim of this study was to investigate the protective effect of 4GMV on the imiquimod (IMQ)-induced psoriasis-like lesions in BALB/c mice and the anti-inflammatory effect on the lipopolysaccharide (LPS)-induced inflammation in RAW264.7 macrophages. The results demonstrated that 4GMV decreased IMQ-induced keratinocyte proliferation and inflammatory cell infiltration. Moreover, 4GMV treatment significantly inhibited the production of NO, PEG 2, and cytokines such as interleukin (IL)-1β, IL-6, interferon (IFN)-γ, and IL-22 in LPS-stimulated RAW264.7 macrophages. 4GMV also suppressed the LPS-upregulated protein expressions of iNOS and COX-2 in a dose-dependent manner. Furthermore, qRT-PCR analysis showed that 4GMV down-regulated the mRNA level of IL-1β and IL-6 expression. Further studies by western blot indicated that 4GMV inhibited the activation of upstream mediator NF-κB by suppressing the expression of TLR4 and the phosphorylation of IκBα and p65. The phosphorylation of JNK, p38, and ERK were also markedly reversed by 4GMV in LPS-treated RAW264.7 macrophages. Taken together, these results demonstrated that 4GMV showed a protective effect in IMQ-induced psoriasis-like mice and inhibited inflammation through the NF-κB and MAPK signaling pathways, indicating that 4GMV might be a potential therapeutic drug for psoriasis.

Anti-Toxoplasma activity and chemical compositions of aquatic extract of Mentha pulegium L. and Rubus idaeus L.: An in vitro study

This study aimed to determine the chemical compositions of crude aquatic extracts of M. pulegium L. and R. idaeus L., and their anti-Toxoplasma activity. Crude aquatic extraction of aerial parts of R. idaeus L. and M. pulegium L. was performed. GC-MS and HTPLC analyses were carried out. MTT assay was performed on Vero cells treated by different concentrations (Log -10 from 10-1 to 10-6) of the extracts. The anti-Toxoplasma activity of the concentrations was investigated using vital staining. Menthol (99.23%) and limonene (0.227%) were the major compounds of the aquatic extract of M. pulegium L. Phytochemical compositions of R. idaeus L. were terpenoids, esterols, and flavonoids. The cell toxicity of M. pulegium L. was lower than R. idaeus L. (CC50 > 10-2 versus. ≥ 10-4). Aquatic extract of M. pulegium L. showed higher anti-Toxoplasma activity (LC50 ≥ 10-6) than R. idaeus L. (LC50 ≥ 10-5). Statistically significant cell toxicity and anti-Toxoplasma activity (p < .05) were seen regarding the different concentrations of R. idaeus L. and M. pulegium L. Both R. idaeus L. and M. pulegium L. revealed anti-Toxoplasma activities. Cell toxicity of R. idaeus L. was significantly higher than M. pulegium L. M. pulegium L. extract could be more applicable due to its lower cell toxicity.