Quercetin-Induced Enhancement of Nasal Epithelial Cells' Ability to Produce Clara Cell 10-kD Protein In Vitro and In Vivo.

Background: Quercetin, a polyphenolic flavonoid found in various plants and foods, is known to have antioxidant, antiviral and anticancer effects. Although quercetin is well known to exert anti-inflammatory and anti-allergic effects, the precise mechanisms by which quercetin favorably modifies the clinical status of allergic diseases, such as allergic rhinitis (AR), remain unclear. The present study examined whether quercetin could modulate the production of the endogenous anti-inflammatory molecule, Clara cell 10-kD protein (CC10), in vitro and in vivo. Methods: Human nasal epithelial cells (1 × 105 cells/mL) were stimulated with 20 ng/mL of tumor necrosis factor-alpha (TNF) in the presence of quercetin for 24 h. CC10 levels in culture supernatants were examined by ELISA. Sprague Dawley rats were sensitised with toluene 2,4-diisocyanate (TDI) by intranasal instillation of 10% TDI in ethyl acetate at a volume of 5.0 µL once daily for five days. This sensitisation procedure was repeated after an interval of two days. The rats were treated with different dosages of quercetin once daily for five days starting on the 5th day following the second sensitization. Nasal allergy-like symptoms induced by the bilateral application of 5.0 µL of 10% TDI were assessed by counting sneezing and nasal-rubbing behaviours for 10 min immediately after the TDI nasal challenge. The levels of CC10 in nasal lavage fluids obtained 6 h after TDI nasal challenge were examined using ELISA. Results: The treatment of cells with low doses of quercetin (<2.5 µM) scarcely affected TNF-induced CC10 production from nasal epithelial cells. However, the ability of nasal epithelial cells to produce CC10 after TNF stimulation significantly increased on treatment with quercetin doses (>5.0 µM). The oral administration of quercetin (>25 mg/kg) for five days significantly increased the CC10 content in nasal lavage fluids and attenuated the nasal symptoms induced by the TDI nasal challenge. Conclusions: Quercetin inhibits AR development by increasing the ability of nasal epithelial cells to produce CC10.

Relationship Between Resilience and Perceived Control After Acute Coronary Syndrome: A Prospective Study.

BACKGROUND: Patients with acute coronary syndrome report poor health-related quality of life and decreased levels of perceived control. Perceived control is a person's belief that they can cope with negative events. Resilience is an adaptation that gives people the capacity to recover from difficult situations, and higher levels of resilience may impact recovery after an acute event. OBJECTIVE: The aim of this study was to analyze the relationship between resilience, perceived control, and health outcomes of patients hospitalized with acute coronary syndrome within 6 months of discharge. METHODS: Data were collected prospectively from adult patients hospitalized with acute coronary syndrome in 3 university hospitals in the Tokyo Metropolitan area, Japan. All data were collected between December 2015 and December 2019. The Sukemune-Hiew Resilience Test (part 1) was used to measure resilience, which includes 3 domains of social support, self-efficacy, and sociality. The Control Attitudes Scale-Revised was used to measure perceived control. Linear regression and path analysis were used to statistically analyze the relationship among variables. RESULTS: Higher resilience, especially self-efficacy, was associated with higher perceived control during admission. Higher resilience, especially social support, during admission was associated with perceived control at 6 months after adjusting for income and education. Higher resilience during admission was associated with better perceived control at 3 months, which was associated with better health outcomes at 6 months. Higher income and lower depression were related to higher resilience. CONCLUSIONS: Nurses should make sure patients with depression, low income, and low social support are connected with appropriate treatment and social support resources.

Factors related to perceived control and health-related quality of life of patients after acute coronary syndrome during admission and after discharge.

AIM: To explore the relationship between demographic factors, acute coronary syndrome-related factors, perceived control and health-related quality of life during admission, 3 months and 6 months after discharge, in patients with acute coronary syndrome. METHODS: Participants were recruited for this longitudinal study after admission for acute coronary syndrome in three university hospitals in the Tokyo metropolitan area, Japan. Self-administered questionnaires included demographic data, perceived control, health-related quality of life, acute coronary syndrome symptoms, fatigue, depression and anxiety. RESULTS: Participants (N = 137) had an average age of 62.8 (SD 11.6) years and 80.3% were male. As a result of Path analysis, higher perceived control (ß = 0.258, p = .001), lower anxiety (ß = -0.226, p = .009) and lower fatigue (ß = -0.231, p = .010), were significantly related to better health-related quality of life (General health). Only annual income was significantly related to perceived control (ß = 0.187, p = .029). Eighty-two (59.9%) participants at 3 months and 54 (39.4%) participants at 6 months completed the questionnaires. Perceived control (F = 7.074, p = .001) and General health (χ2 = 10.22, p = .006) significantly increased over the 6 months. Perceived control during admission was significantly related with health-related quality of life at 3 months. Perceived control at 3 months was significantly related with health-related quality of life at 6 months. CONCLUSION: Perceived control was an important factor for health-related quality of life of the Japanese patients with acute coronary syndrome. It is necessary to investigate whether nursing interventions to enhance perceived control lead to improvement of health-related quality of life.

Quercetin Enhances the Thioredoxin Production of Nasal Epithelial Cells In Vitro and In Vivo.

Background: Thioredoxin (TRX) acts as both a scavenger of reactive oxygen species (ROS) and an immuno-modulator. Although quercetin has been shown to favorably modify allergic rhinitis (AR) symptoms, its influence on TRX production is not well defined. The present study was designed to examine whether quercetin could favorably modify AR symptoms via the TRX production of nasal epithelial cells in vitro and in vivo. Methods: Human nasal epithelial cells (HNEpCs) were stimulated with H2O2 in the presence of quercetin. TRX levels in 24-h culture supernatants were examined with ELISA. BALB/c male mice were intraperitoneally sensitized to ovalbumin (OVA) and intranasally challenged with OVA every other day, beginning seven days after the final sensitization. The mice were orally administered quercetin once a day for five consecutive days, beginning seven days after the final sensitization. Nasal symptoms were assessed by counting the number of sneezes and nasal rubbing behaviors during a 10-min period immediately after the challenge. TRX levels in nasal lavage fluids obtained 6 h after the challenge were examined by ELISA. Results: Treatment with 1.0 nM quercetin increased H2O2-induced TRX levels. The oral administration of 20.0 mg/kg of quercetin significantly inhibited nasal symptoms after the challenge. The same dose of quercetin significantly increased TRX levels in nasal lavage fluids. Conclusions: Quercetin's ability to increase TRX production may account, at least in part, for its clinical efficacy toward AR.