Reversal of methylprednisolone effects in allergen-exposed female BALB/c mice

Pharmacokinetic Study of Intranasal Dexamethasone and Methylprednisolone Compared with Intravenous Administration: Two Open-Label, Single-Dose, Two-Period, Two-Sequence, Cross-Over Study in Healthy Volunteers

Dexamethasone (DXM) and methylprednisolone (MEP) are potent glucocorticoids used to control several inflammatory conditions. Evidence of delayed DXM reaching the central nervous system (CNS) as well as tachyphylaxis and systemic, undesirable side effects are the main limitations of peripheral delivery. Intranasal administration offers direct access to the brain as it bypasses the blood-brain barrier. The Mucosal Atomization Device is an optimal tool that can achieve rapid absorption into the CNS and the bloodstream across mucosal membranes. This study was designed to evaluate and compare the bioavailability of DXM and MEP after intranasal versus intravenous administration. Two open-label, balanced, randomized, two-treatment, two-period, two-sequence, single-dose, crossover studies were conducted, which involved healthy male and female adult volunteers. After intranasal administration, DXM and MEP were detected in plasma after the first sampling time. Mean peak concentrations of DXM and MEP were 86.61 ng/mL at 60 min and 843.2 ng/mL at 1.5 h post-administration, respectively. DXM and MEP showed high absolute bioavailability, with values of 80% and 95%, respectively. No adverse effects were observed. DXM and MEP systemic bioavailability by intranasal administration was comparable with the intravenous one, suggesting that the intranasal route can be used as a non-invasive and appropriate alternative for systemic drug delivery.

Anti-Inflammatory Food in Asthma Prepared from Combination of Raphanus sativus L., Allium hookeri, Acanthopanax sessiliflorum, and Dendropanax morbiferus Extracts via Bioassay-Guided Selection

Asthma is a highly prevalent inflammatory disease of the respiratory airways and an increasing health risk worldwide. Hence, finding new strategies to control or attenuate this condition is necessary. This study suggests nutraceuticals that are a combination of herbal plant extracts prepared from Acanthopanax sessiliflorum (AS), Codonopsis lanceolate (CL), Dendropanax morbiferus (DM), Allium hookeri (AH), and Raphanus sativus L. (RS) that can improve immunomodulatory ability through the detoxification and diuresis of air pollutants. Herbal parts (AH whole plant, RS and CL roots, AS and DM stems, and DM leaves) were selected, and four types of mixtures using plant extracts were prepared. Among these mixtures, M2 and M4 exhibited antioxidant activities in potent 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and 1,1-diphenyl-β-picrylhydrazine (DPPH) radical assays. Moreover, M4 exhibited a marked increase in glutathione S-transferase (GST) activity and significantly inhibited the inflammatory mediator, nitric oxide (NO) and proinflammatory cytokines, interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α generation. Furthermore, M4 exhibited the strongest antioxidant, hepatoprotective, and anti-inflammatory effects and was selected to prepare the product. Before manufacturing the product, we determined that the active mixture, M4, inhibited gene expression and generation of proinflammatory cytokines IL-1β, IL-6 and TNF-α in ovalbumin (OVA)-, lipopolysaccharide (LPS)-, and particulate matter (PM)-induced asthmatic rat models. The granular product (GP) was manufactured using M4 along with additives, i.e., lactose, oligosaccharide, stevioside extract, and nutmeg seed essential oils (flavor masking), in a ratio of 1:4 using a granulation machine, dried and ultimately packaged. The GP inhibited the generation of proinflammatory cytokines IL-1β, IL-6 and TNF-α in OVA-, LPS- and PM-induced asthmatic rat models. These results suggest that GP prepared from a combination of herbal plants (AS, CL, DM, AH and RS) is a potent functional food with anti-inflammatory activity that can be used to treat asthma caused by ambient air pollutants.

Immunomodulatory and anti-inflammatory effects of Aerva lanata in ovalbumin induced allergic asthmatic mice

ETHNOPHARMACOLOGICAL RELEVANCE

Aerva lanata Linn. (A. lanata) is traditionally used for cough, sore throat and asthma.

AIM OF STUDY

The aim of the present study was to investigate the immunomodulatory and anti-inflammatory potentials of A. lanata in allergic asthmatic mice.

MATERIALS AND METHODS

BALB/c mice were administered with three different (methanol, n-hexane and ethyl acetate) extracts of A. lanata two weeks after immunization with ovalbumin and continued for 7 days. Inflammatory cells count was estimated in blood and broncho-alveolar lavage fluid (BALF). RT-PCR was used to find out mRNA expression levels of inflammatory mediators. GC-MS analysis was also carried out.

RESULTS

Among three extracts of A. lanata, ethyl acetate extract ameliorated (p < 0.001) count of inflammatory cells both blood and BALF remarkably. This study indicated that ethyl acetate extract of A. lanata lowered (p < 0.001) the level of inflammatory modulator TNF-α and IgE antibodies. A. lanata reduced (p < 0.001) interleukin 4, 5, 13 and enhanced (p < 0.001) expression levels of AQP1 and AQP5 in asthmatic mice. GC-MS analysis of ethyl acetate fraction indicated the presence of various anti-oxidant phyto-constituents. The groups treated with A. lanata improved inflammatory, goblet cells hyperplasia scoring and alveolar thickening.

CONCLUSIONS

The anti-asthmatic effect of A. lanata might be contributed by the suppression of edema, pro-inflammatory cytokines and IgE antibodies, and elevation of aquaporin expression levels, suggesting future study and clinical trials to propose it as a candidate to treat allergic asthma. The anti-oxidant phytochemicals present in A. lanata might be responsible for such potential.

Oxyresveratrol ameliorates allergic airway inflammation via attenuation of IL-4, IL-5, and IL-13 expression levels

AIM

Oxyresveratrol is known to possess anti-inflammatory property. Current study investigates the immunosuppressive effect of oxyresveratrol by using mouse model of ovalbumin (OVA)-induced allergic airway inflammation.

METHODS

BALB/c mice were randomly divided into five groups having 8 mice in each group. Treatment with low dose (7 mg/kg) and high dose (15 mg/kg) of oxyresveratrol, and methylprednisolone (15 mg/kg; standard drug) was started 2 week after immunization of mice with ovalbumin and continued for 7d. Ovalbumin was also injected into pinna of right ear 24h before sacrificing the mice to evaluate delayed type hypersensitivity (DTH). H&E and PAS staining were used for histopathological evaluation of lungs. Reverse transcription polymerase chain reaction followed by gel electrophoresis were used for evaluation of mRNA expression levels of IL-4, IL-5, and IL-13.

RESULTS

Oxyresveratrol significantly reduced total leucocyte count in both blood and bronchoalveolar lavage fluid (BALF). Treatment with oxyresveratrol normalized altered eosinophil and neutrophil counts in both blood and BALF. OVA-specific T-cell response was also significantly inhibited by oxyresveratrol. A significant attenuation of inflammatory cell infiltration and goblet cell hyperplasia was observed after treatment with oxyresveratrol. Data showed that oxyresveratrol significantly suppressed Th2 (T helper cells) type immune response which was obvious by the reduction in mRNA expression levels of IL-4, IL-5, and IL-13. Similarly, treatment with methylprednisolone also significantly reduced all the immunomodulatory and inflammatory parameters.

CONCLUSIONS

Our study demonstrates that oxyresveratrol ameliorates allergic asthma. The anti-asthmatic activity might in part occur via the down regulation of IL-4, IL-5, and IL-13 expression levels.

Zingiber officinale ameliorates allergic asthma via suppression of Th2-mediated immune response

CONTEXT

Ginger has been used commonly in the traditional system of medicine for the treatment of respiratory disorders.

OBJECTIVE

The present study investigates the immunosuppressive activity of ginger by using the mouse model of ovalbumin-induced allergic asthma.

MATERIALS AND METHODS

Treatment with ethanol extract (500 mg/kg) and aqueous extract (720 mg/kg) of rhizomes, and methylprednisolone (5 mg/kg) was initiated 1 week after second sensitization of mice with ovalbumin and continued for 7 d. RT-PCR followed by gel electrophoresis and ELISA were used for the evaluation of mRNA expression levels and protein levels of Th2 type markers, respectively. Lung tissue histopathology was conducted by using H&E and PAS staining.

RESULTS

We observed significant reduction in goblet cell hyperplasia (0.83 ± 0.17 and 1.0 ± 0.26), infiltration of inflammatory cells in airways (0.67 ± 0.33 and 1.0 ± 0.37), and edema with vascular congestion (1.0 ± 0.26 and 1.2 ± 0.17) by both ethanol and aqueous extracts, respectively. A highly significant reduction of total and differential count of eosinophils and neutrophils in BALF, and eosinophil count in blood were also observed. Both extracts significantly inhibited Th2-mediated immune response, which is evident by a decrease in mRNA expression levels of IL-4 and IL-5. Protein levels of IL-4 and IL-5 in BALF, along with total serum IgE levels, were also significantly suppressed by both extracts.

DISCUSSION AND CONCLUSION

Our study validated the traditional use of ginger in respiratory disorders and suggests that ginger reduces allergic airway inflammation, possibly by the suppression of Th2-mediated immune response.

No beneficial effect of general and specific anti-inflammatory therapies on aortic dilatation in Marfan mice

Aims

Patients with Marfan syndrome have an increased risk of life-threatening aortic complications, mostly preceded by aortic dilatation. In the FBN1^C1039G/+ Marfan mouse model, losartan decreases aortic root dilatation. We recently confirmed this beneficial effect of losartan in adult patients with Marfan syndrome. The straightforward translation of this mouse model to man is reassuring to test novel treatment strategies. A number of studies have shown signs of inflammation in aortic tissue of Marfan patients. This study examined the efficacy of anti-inflammatory therapies in attenuating aortic root dilation in Marfan syndrome and compared effects to the main preventative agent, losartan.

Methods and Results

To inhibit inflammation in FBN1^C1039G/+ Marfan mice, we treated the mice with losartan (angiotensin II receptor type 1 inhibitor), methylprednisolone (corticosteroid) or abatacept (T-cell-specific inhibitor). Treatment was initiated in adult Marfan mice with already existing aortic root dilatation, and applied for eight weeks. Methylprednisolone- or abatacept-treated mice did not reveal a reduction in aortic root dilatation. In this short time frame, losartan was the only treatment that significantly reduced aorta inflammation, transforming growth factor-beta (TGF-β) signaling and aortic root dilatation rate in these adult Marfan mice. Moreover, the methylprednisolone-treated mice had significantly more aortic alcian blue staining as a marker for aortic damage.

Conclusion

Anti-inflammatory agents do not reduce the aortic dilatation rate in Marfan mice, but possibly increase aortic damage. Currently, the most promising therapeutic drug in Marfan syndrome is losartan, by blocking the angiotensin II receptor type 1 and thereby inhibiting pSmad2 signaling.

Recurring BALB/c mouse lung inflammatory responses to episodic allergen exposure

This study detailed the sequence of recurring inflammatory events associated with episodic allergen exposures of mice resulting in airway hyperreactivity, sustained inflammation, goblet-cell hyperplasia, and fibrogenesis that characterize a lung with chronic asthma. Ovalbumin (OVA)-sensitized female BALB/c mice were exposed to saline-control or OVA aerosols for 1 h per day for episodes of 3 d/wk for up to 8 wk. Lung inflammation was assessed by inflammatory cell recoveries using bronchoalveolar lavages (BAL) and tissue collagenase dispersions. Cell accumulations were observed within airway submucosal and associated perivascular spaces using immunohistochemical and tinctorial staining methods. Airway responsiveness to methacholine aerosols were elevated after 2 wk and further enhanced to a sustained level after wk 4 and 8. Although by wk 8 diminished OVA-induced accumulations of eosinophils, neutrophils, and monocyte-macrophages were observed, suggesting diminished responsiveness, the BAL recovery of lymphocytes remained elevated. Airway but not perivascular lesions persisted with a proliferating cell population, epithelial goblet-cell hyperplasia, and evidence of enhanced collagen deposition. Examination of lung inflammatory cell content before the onset of the first, second, and fourth OVA exposure episodes demonstrated enhancements in residual BAL lymphocyte and BAL and tissue eosinophil recoveries with each exposure episode. Although tissue monocyte-macrophage numbers returned to baseline prior to each exposure episode, the greatest level of accumulation was observed after wk 4. These results provide the basis for establishing the inflammatory and exposure criteria by which episodic environmental exposures to allergen might result in the development of a remodeled lung in asthma.

Cytochrome c oxidase subunit 4 isoform 2-knockout mice show reduced enzyme activity, airway hyporeactivity, and lung pathology

Cytochrome c oxidase (COX) is the terminal enzyme of the mitochondrial electron transport chain. The purpose of this study was to analyze the function of lung-specific cytochrome c oxidase subunit 4 isoform 2 (COX4i2) in vitro and in COX4i2-knockout mice in vivo. COX was isolated from cow lung and liver as control and functionally analyzed. COX4i2-knockout mice were generated and the effect of the gene knockout was determined, including COX activity, tissue energy levels, noninvasive and invasive lung function, and lung pathology. These studies were complemented by a comprehensive functional screen performed at the German Mouse Clinic (Neuherberg, Germany). We show that isolated cow lung COX containing COX4i2 is about twice as active (88 and 102% increased activity in the presence of allosteric activator ADP and inhibitor ATP, respectively) as liver COX, which lacks COX4i2. In COX4i2-knockout mice, lung COX activity and cellular ATP levels were significantly reduced (-50 and -29%, respectively). Knockout mice showed decreased airway responsiveness (60% reduced P(enh) and 58% reduced airway resistance upon challenge with 25 and 100 mg methacholine, respectively), and they developed a lung pathology deteriorating with age that included the appearance of Charcot-Leyden crystals. In addition, there was an interesting sex-specific phenotype, in which the knockout females showed reduced lean mass (-12%), reduced total oxygen consumption rate (-8%), improved glucose tolerance, and reduced grip force (-14%) compared to wild-type females. Our data suggest that high activity lung COX is a central determinant of airway function and is required for maximal airway responsiveness and healthy lung function. Since airway constriction requires energy, we propose a model in which reduced tissue ATP levels explain protection from airway hyperresponsiveness, i.e., absence of COX4i2 leads to reduced lung COX activity and ATP levels, which results in impaired airway constriction and thus reduced airway responsiveness; long-term lung pathology develops in the knockout mice due to impairment of energy-costly lung maintenance processes; and therefore, we propose mitochondrial oxidative phosphorylation as a novel target for the treatment of respiratory diseases, such as asthma.

Wnt-4 protects thymic epithelial cells against dexamethasone-induced senescence

Glucocorticoids are widely used immunosuppressive drugs in treatment of autoimmune diseases and hematological malignancies. Glucocorticoids are particularly effective immune suppressants, because they induce rapid peripheral T cell and thymocyte apoptosis resulting in impaired T cell-dependent immune responses. Although glucocorticoids can induce apoptotic cell death directly in developing thymocytes, how exogenous glucocorticoids affect the thymic epithelial network that provides the microenvironment for T cell development is still largely unknown. In the present work, we show that primary thymic epithelial cells (TECs) express glucocorticoid receptors and that high-dosage dexamethasone induces degeneration of the thymic epithelium within 24 h of treatment. Changes in organ morphology are accompanied by a decrease in the TEC transcription factor FoxN1 and its regulator Wnt-4 parallel with upregulation of lamina-associated polypeptide 2α and peroxisome proliferator activator receptor γ, two characteristic molecular markers for adipose thymic involution. Overexpression of Wnt-4, however, can prevent upregulation of adipose differentiation-related aging markers, suggesting an important role of Wnt-4 in thymic senescence.