Dictamnus dasycarpus Turcz. attenuates airway inflammation and mucus hypersecretion by modulating the STAT6-STAT3/FOXA2 pathway

BACKGROUND

Effects of Dictamnus dasycarpus Turcz. on allergic asthma and their underlying mechanisms remain unclarified. Thus, we investigated the effects of D. dasycarpus Turcz. water extract (DDW) on mucus hypersecretion in mice with ovalbumin (OVA)-induced asthma and human bronchial epithelial cells.

METHODS

BALB/c mice were used to establish an OVA-induced allergic asthma model. Mice were grouped into the OVA sensitization/challenge, 100 and 300 mg/kg DDW treatment, and dexamethasone groups. In mice, cell counts in bronchoalveolar lavage fluid (BALF), serum and BALF analyses, and histopathological lung tissue analyses were performed. Furthermore, we confirmed the basic mechanism in interleukin (IL)-4/IL-13-treated human bronchial epithelial cells through western blotting.

RESULTS

In OVA-induced asthma mice, DDW treatment reduced inflammatory cell number and airway hyperresponsiveness and ameliorated histological changes (immune cell infiltration, mucus secretion, and collagen deposition) in lung tissues and serum total immunoglobulin E levels. DDW treatment lowered BALF IL-4, IL-5, and IL-13 levels; reduced levels of inflammatory mediators, such as thymus- and activation-regulated chemokine, macrophage-derived chemokine, and interferon gamma-induced protein; decreased mucin 5AC (MUC5AC) production; decreased signal transducer and activator of transcription (STAT) 6 and STAT3 expression; and restored forkhead box protein A2 (FOXA2) expression. In IL-4/IL-13-treated human bronchial epithelial cells, DDW treatment inhibited MUC5AC production, suppressed STAT6 and STAT3 expression (related to mucus hypersecretion), and increased FOXA2 expression.

CONCLUSIONS

DDW treatment modulates MUC5AC expression and mucus hypersecretion by downregulating STAT6 and STAT3 expression and upregulating FOXA2 expression. These findings provide a novel approach to manage mucus hypersecretion in asthma using DDW.

Therapeutic effects of Pulsatilla koreana Nakai extract on ovalbumin-induced allergic rhinitis by inhibition of Th2 cell activation and differentiation via the IL-4/STAT6/GATA3 pathway

Allergic rhinitis (AR), caused by immunoglobulin E (IgE)-mediated inflammation, generally occurs in the upper respiratory tract. T helper type 2 (Th2) cell-mediated cytokines, including interleukin (IL)-4, IL-5, and IL-13, are important factors in AR pathogenesis. Despite various treatment options, the difficulty in alleviating AR and pharmacological side effects necessitate development of new therapies. The root of Pulsatilla koreana Nakai (P. koreana), a pasque flower, has been used as a herbal medicine. However, its effects on AR remain unclear; therefore, we aimed to explore this subject in the current study. The therapeutic effects of P. koreana water extract (PKN) on the pathophysiological functions of the nasal mucosa was examined in ovalbumin (OVA)-induced AR mice. The effect of PKN on Th2 activation and differentiation was evaluated using concanavalin A-induced splenocytes and differentiated Th2 cells from naïve CD4⁺ T cells. We also investigated the effect of changes in JAK/STAT6/GATA3 signaling on IL-4-induced Th2 cells. In OVA-induced AR mice, PKN administration alleviated allergic nasal symptoms and decreased the total number of immune cells, lymphocytes, neutrophils, and eosinophils in nasal lavage fluid; serum levels of OVA-specific IgE, histamine, and IL-13 were also significantly reduced. PKN also ameliorated OVA-induced nasal mucosal tissue thickening by inhibiting inflammation and goblet cell hyperplasia. PKN treatment significantly inhibited Th2 activity and differentiation through the IL-4/STAT-6/GATA3 pathway in Th2 cells. PKN is an effective AR treatment with the potential to improve patients' daily lives by regulating the allergic inflammatory response induced by Th2 cells.

Gleditsia sinensis Lam. aqueous extract attenuates nasal inflammation in allergic rhinitis by inhibiting MUC5AC production through suppression of the STAT3/STAT6 pathway

Allergic rhinitis (AR), a chronic respiratory inflammatory disease, is among the most common chronic diseases reported worldwide. Mucus hypersecretion is a critical feature of AR pathogenesis. Although the Gleditsia sinensis extract has several beneficial effects on human health, its effects on allergic inflammation have not yet been investigated. In this study, we examined the effects of G. sinensis aqueous extract (GSAE) on nasal inflammation in an ovalbumin (OVA)-induced AR mouse model. GSAE was administered orally for 1 week and then the clinical nasal symptoms were evaluated. The levels of histamine, OVA-specific immunoglobulin (Ig) E, and interleukin (IL)-13 were measured in the serum using an enzyme-linked immunosorbent assay (ELISA). Inflammatory cells were then counted in the nasal lavage fluid (NALF) and histopathology in the nasal epithelium was evaluated. STAT3/STAT6 phosphorylation was examined in primary human nasal epithelial cells (HNEpCs) using western blot analysis. Oral administration of GSAE to OVA-induced AR mice alleviated nasal clinical symptoms and reduced OVA-specific immunoglobulin E, interleukin (IL)-13, and histamine levels. The accumulation of eosinophils in nasal lavage fluid, nasal mucosa, mast cells, goblet cells, and mucin 5AC (MUC5AC) in the nasal epithelium was also inhibited by GSAE. Treatment with GSAE inhibited the production of MUC5AC in IL-4/IL-13-stimulated primary human nasal epithelial cells through the signal transducer and activator of transcription (STAT)3/STAT6 signaling pathway. These results indicated that GSAE reduces nasal inflammation suggesting that it is a potential treatment option for AR.

Caesalpinia sappan Linn. Ameliorates Allergic Nasal Inflammation by Upregulating the Keap1/Nrf2/HO-1 Pathway in an Allergic Rhinitis Mouse Model and Nasal Epithelial Cells

Allergic rhinitis (AR) is a common upper-airway inflammatory disease of the nasal mucosa caused by immunoglobulin (IgE)-mediated inflammation. AR causes various painful clinical symptoms of the nasal mucosa that worsen the quality of daily life, necessitating the urgent development of therapeutic agents. Herein, we investigated the effects of Caesalpinia sappan Linn. heartwood water extract (CSLW), which has anti-inflammatory and antioxidant properties, on AR-related inflammatory responses. We examined the anti-inflammatory and anti-allergic effects of CSLW in ovalbumin (OVA)-induced AR mice and in primary human nasal epithelial cells (HNEpCs). Administration of CSLW mitigated allergic nasal symptoms in AR mice, decreased total immune cell and eosinophil counts in nasal lavage fluid, and significantly reduced serum levels of OVA-specific IgE, histamine, and Th2 inflammation-related cytokines. CSLW also inhibited the infiltration of several inflammatory and goblet cells, thereby ameliorating OVA-induced thickening of the nasal mucosa tissue. We found that CSLW treatment significantly reduced infiltration of eosinophils and production of periostin, MUC5AC, and intracellular reactive oxygen species through the Keap1/Nrf2/HO-1 pathway in HNEpCs. Thus, our findings strongly indicate that CSLW is a potent therapeutic agent for AR and can improve the daily life of patients by controlling the allergic inflammatory reaction of the nasal epithelium.

Angelica gigas extract ameliorates allergic rhinitis in an ovalbumin-induced mouse model by inhibiting Th2 cell activation

BACKGROUND

Allergic rhinitis (AR) is a well-documented type 2 helper T (Th2) cell-mediated allergic disease that is accompanied by symptoms such as nasal rubbing, sneezing, itching, and rhinorrhea. Angelica gigas (AG) is traditional oriental medicine, and its dried root is widely used for the treatment of anemia, as a sedative, and as a blood tonic.

PURPOSE

The effects of AG on allergic diseases including AR are currently unclear; therefore, we aimed to investigate the effects of AG extract (AG-Ex) in ameliorating AR.

STUDY DESIGN/METHODS

The cytotoxicity of AG-Ex was analyzed by EZ-Cytox or MTS assay in splenocytes, differentiated Th2 cells, and human nasal epithelial cells (HNEpC). The changes of Th2 cells activation were determined by the secretion levels of cytokines and chemokines using cytometric bead array in splenocytes and differentiated Th2 cells. The expression levels of eotaxin-3 and periostin were analyzed using an ELISA. AR was induced by ovalbumin in BALB/c mice and the ameliorating effects of AG-Ex were assessed by their clinical symptoms.

RESULTS

The secretion of Th2 cytokines such as IL-4, IL-5, and IL-13 was inhibited by the AG-Ex treatment in the splenocytes and differentiated Th2 cells. The treatment also suppressed allergic responses including the secretion of eotaxin-3 and periostin in human nasal epithelial cells (HNEpC). Moreover, the administration of AG-Ex to the OVA-induced AR mice improved their clinical symptoms, including behavioral tests, immune cell counts, histopathological analysis, and changes in serum parameters.

CONCLUSION

The results of this study suggest that AG-Ex ameliorates AR by inhibiting Th2 cell activation and could thus be utilized as a treatment for Th2-mediated allergic diseases in the future.

Gardenia jasminoides Attenuates Allergic Rhinitis-Induced Inflammation by Inhibiting Periostin Production

Allergic rhinitis (AR) is a chronic inflammatory condition affecting the nasal mucosa of the upper airways. Herein, we investigated the effects of extracts from Gardenia jasminoides (GJ), a traditional herbal medicine with anti-inflammatory properties, on AR-associated inflammatory responses that cause epithelial damage. We investigated the inhibitory effects of water- and ethanol-extracted GJ (GJW and GJE, respectively) in an ovalbumin-induced AR mouse model and in splenocytes, differentiated Th2 cells, and primary human nasal epithelial cells (HNEpCs). Administering GJW and GJE to ovalbumin-induced AR mice improved clinical symptoms including behavior (sneezing and rubbing), serum cytokine levels, immune cell counts, and histopathological marker levels. Treatment with GJW and GJE reduced the secretion of Th2 cytokines in Th2 cells isolated and differentiated from the splenocytes of these mice. To investigate the underlying molecular mechanisms of AR, we treated IL-4/IL-13-stimulated HNEpCs with GJW and GJE; we found that these extracts significantly reduced the production of mitochondrial reactive oxygen species via the uncoupling protein-2 and periostin, a biomarker of the Th2 inflammatory response. Our results suggest that GJ extracts may potentially serve as therapeutic agents to improve the symptoms of AR by regulating the Th2 inflammatory response of the nasal epithelium.

Anti-allergic effects of Asarum heterotropoides on an ovalbumin-induced allergic rhinitis murine model

Allergic rhinitis (AR) is a common chronic respiratory disease. Asarum heterotropoides (AH) is predicted to be a treatment for allergic diseases, but its therapeutic effect is unclear. We aimed to determine the anti-allergic effects of AH in mice with ovalbumin (OVA)-induced AR. OVA-induced AR mouse model was constructed, and AH was orally administered for a week; next, nasal clinical symptoms were evaluated. The levels of serum histamine, OVA-specific IgE, and IL-13 were measured by ELISA. Inflammatory cells, including leukocytes, neutrophils, eosinophils, and macrophages were counted in the nasal lavage fluid (NALF). Histopathological examinations of the nasal tissues were performed using H&E, Giemsa, and PAS staining. The production of periostin and eotaxin-3 from AH-treated human nasal epithelial cells (HNEpCs) in vitro, was measured using ELISA. Oral administration of AH alleviated allergic symptoms in mice with AR; significantly decreased levels of allergic mediators, such as serum histamine and OVA-specific IgE. The decrease in allergic symptoms positively correlated with the decrease in serum allergic mediators. The NALF of AH-treated AR mice demonstrated lower number of eosinophils. AH demonstrated a capacity to reduce the infiltration of mast cells, eosinophils, and goblet cells, thereby resulting in thinner nasal tissues. Moreover, treatment of HNEpCs with AH demonstrated suppressed production of periostin and eotaxin-3. AH exerts a therapeutic effect in modulating AR through multi-target and multi-function influence on regulating B cells, mast cells, eosinophils, goblet cells, and epithelial cells.

Laxative Activity of the Hot-Water Extract Mixture of Hovenia dulcis Thunb. and Phyllostachys pubescens Mazel in Chronic Constipation Model SD Rats

This study examined the laxative effects of hot-water extracts of Hovenia dulcis Thunb. (HD), Phyllostachys pubescens Mazel (PM), and a 2:8 mixture of both (HP) in two chronic constipation models. For the loperamide-induced constipation model, animals were divided into an untreated group, negative control group (loperamide 4 mg/kg), positive control group (bisacodyl 4 mg/kg) group, and six treatment groups (HP 100 or 400, HD 50 or 100, and PM 100 or 400 mg/kg). For the lowfiber diet-induced constipation model, animals were divided into an untreated group (normal diet), negative control group (low-fiber diet), positive control group (Agio granule, 620 mg/kg), and the same treatment groups. Fecal number, weight, fecal water content, and intestinal transit ratio were higher in the groups treated with HP, HD, and PM than in the groups treated with loperamide or lowfiber diet. Thickness of colon mucosa and muscle layers were increased in the treated groups. Colon tension increased in the HP groups, and [Ca2+]i measurements using fura-2 as an indicator showed that HP inhibits ATP-mediated Ca2+ influx in IEC-18 cells. These results showed that the HP mixture has laxative activity by increased mucin secretion and inducing contractile activity and relaxation. It may be a useful therapeutic strategy for ameliorating in chronic constipation.

In vitro and in vivo androgen regulation of Dendropanax morbiferus leaf extract on late-onset hypogonadism

Late-onset hypogonadism (LOH) is associated with advancing age and is caused by a deficiency in serum testosterone levels. The aim of this study was to examine the effect of a Dendropanax morbiferus H.Lév. leaf extract (DME) on LOH using TM3 cells and aging male rats as in vitro and in vivo models, respectively. The in vitro effects of DME on testosterone levels and 3β-hydroxysteroid dehydrogenase (3β-HSD) protein expression in TM3 cells were analyzed. In the in vivo experiments, DME was orally administered to rats at three doses (50, 100, and 200 mg/kg/day) for 4 weeks. DME significantly increased the testosterone levels and 3β-HSD protein expression in TM3 cells. The DME groups showed significantly increased levels of androgenic hormones such as testosterone and dehydroepiandrosterone sulfate. The sex hormone-binding globulin production was significantly lower in the DME groups than that in the control group, while the neurohormone levels in the hypothalamic–pituitary–gonadal axis markedly increased. No significant differences were observed in the glutamic pyruvic transaminase, glutamic oxaloacetic transaminase, and prostate-specific antigen levels among the DME and control groups. The triglyceride and low-density lipoprotein cholesterol levels were significantly lower, while the high-density lipoprotein cholesterol levels were significantly higher in the DME groups than those in the control group. The latency time in the rotarod, treadmill, and swimming tests increased with the DME treatment. Furthermore, the sperm counts in the epididymis markedly increased. These results suggest that DME can be effectively used to alleviate the symptoms of LOH.

In vitro and in vivo androgen regulation of Dendropanax morbiferus leaf extract on late-onset hypogonadism

Late-onset hypogonadism (LOH) is associated with advancing age and is caused by a deficiency in serum testosterone levels. The aim of this study was to examine the effect of a Dendropanax morbiferus H.Lév. leaf extract (DME) on LOH using TM3 cells and aging male rats as in vitro and in vivo models, respectively. The in vitro effects of DME on testosterone levels and 3β-hydroxysteroid dehydrogenase (3β-HSD) protein expression in TM3 cells were analyzed. In the in vivo experiments, DME was orally administered to rats at three doses (50, 100, and 200 mg/kg/day) for 4 weeks. DME significantly increased the testosterone levels and 3β-HSD protein expression in TM3 cells. The DME groups showed significantly increased levels of androgenic hormones such as testosterone and dehydroepiandrosterone sulfate. The sex hormone-binding globulin production was significantly lower in the DME groups than that in the control group, while the neurohormone levels in the hypothalamic-pituitary-gonadal axis markedly increased. No significant differences were observed in the glutamic pyruvic transaminase, glutamic oxaloacetic transaminase, and prostate-specific antigen levels among the DME and control groups. The triglyceride and low-density lipoprotein cholesterol levels were significantly lower, while the high-density lipoprotein cholesterol levels were significantly higher in the DME groups than those in the control group. The latency time in the rotarod, treadmill, and swimming tests increased with the DME treatment. Furthermore, the sperm counts in the epididymis markedly increased. These results suggest that DME can be effectively used to alleviate the symptoms of LOH.

Vaccinium bracteatum Leaf Extract Reverses Chronic Restraint Stress-Induced Depression-Like Behavior in Mice: Regulation of Hypothalamic-Pituitary-Adrenal Axis, Serotonin Turnover Systems, and ERK/Akt Phosphorylation

The leaves of Vaccinium bracteatum Thunb. are a source of traditional herbal medicines found in East Asia. The present study aimed to evaluate the mechanisms underlying the antidepressant-like effects of water extract of V. bracteatum Thunb. leaves (VBLW) in a mouse model of chronic restraint stress (CRS) and to identify the possible molecular in vitro mechanisms of the neuroprotective effects. The CRS-exposed mice were orally administered VBLW (100 and 200 mg/kg) daily for 21 days consecutively. The behavioral effects of VBLW were assessed through the forced swim test (FST) and the open field test (OFT). The levels of serum corticosterone (CORT), corticotropin releasing hormone (CRH), and adrenocorticotropin hormone (ACTH), brain monoamines, such as serotonin, dopamine, and norepinephrine, and serotonin turnover by tryptophan hydroxylase 2 (TPH2), serotonin reuptake (SERT), and monoamine oxidase A (MAO-A) were evaluated, in addition to the extracellular signal-regulated kinases (ERKs)/protein kinase B (Akt) signaling pathway. CRS-exposed mice treated with VBLW (100 and 200 mg/kg) showed significantly reduced immobility time and increased swimming and climbing times in the FST, and increased locomotor activity in the OFT. Moreover, CRS mice treated with VBLW exhibited significantly decreased CORT and ACTH, but enhanced brain monoamine neurotransmitters. In addition, CRS mice treated with VBLW had dramatically decreased protein levels of MAO-A and SERT, but increased TPH2 protein levels in the hippocampus and the PFC. Similarly, VBLW significantly upregulated the ERKs/Akt signaling pathway in the hippocampus and the PFC. Furthermore, VBLW showed neuroprotective effects via increased CREB phosphorylation in CORT-induced cell injury that were mediated through the ERK/Akt/mTOR signaling pathways. These results suggested that the antidepressant-like effects of VBLW might be mediated by the regulation of the HPA axis, glucocorticoids, and serotonin turnover, such as TPH2, SERT, and MAO-A, as well as the concentration of monoamine neurotransmitters, and the activities of ERK and Akt phosphorylation, which were possibly associated with neuroprotective effects.

Antidepressant-Like Effects of Vaccinium bracteatum in Chronic Restraint Stress Mice: Functional Actions and Mechanism Explorations

The fruit of Vaccinium bracteatum Thunb. (VBF) is commonly known as the oriental blueberry in Korea. The aim of this study was to evaluate the antidepressant-like effects of water VBF extract (VBFW) in a mouse model of chronic restraint stress (CRS) and to identify the underlying mechanisms of its action. The behavioral effects of VBFW were assessed in the forced swim test (FST) and open field test (OFT). The levels of serum corticosterone (CORT), brain monoamines, in addition to the extracellular signal-regulated kinases (ERKs)/protein kinase B (Akt) signaling pathway were evaluated. VBFW treatment significantly reduced the immobility time and increased swimming time in FST without altering the locomotor activity in unstressed mice. Furthermore, CRS mice treated with VBFW exhibited a significantly decreased immobility time in FST and serum CORT, increased locomotor activity in OFT, and enhanced brain monoamine neurotransmitters. Similarly, VBFW significantly upregulated the ERKs/Akt signaling pathway in the hippocampus and PFC. In addition, VBFW may reverse CORT-induced cell death by enhancing cyclic AMP-responsive element-binding protein expression through the up-regulation of ERKs/Akt signaling pathways. In addition, VBFW showed the strong antagonistic effect of the 5-HT[Formula: see text] receptor by inhibiting 5-HT-induced intracellular Ca[Formula: see text] and ERK1/2 phosphorylation. Our study provides evidence that antidepressant-like effects of VBFW might be mediated by the regulation of monoaminergic systems and glucocorticoids, which is possibly associated with neuroprotective effects and antagonism of 5-HT[Formula: see text] receptor.