Eeva Moilanen

Probiotics in the management of atopic eczema

Over the last two decades the incidence of allergic diseases has increased in industrialized countries, and consequently new approaches have to be explored.

Anti-Inflammatory Effects of Flavonoids: Genistein, Kaempferol, Quercetin, and Daidzein Inhibit STAT-1 and NF-κB Activations, Whereas Flavone, Isorhamnetin, Naringenin, and Pelargonidin Inhibit only NF-κB Activation along with Their Inhibitory Effect on iNOS Expression and NO Production in Activated Macrophages

In inflammation, bacterial products and proinflammatory cytokines induce the formation of large amounts of nitric oxide (NO) by inducible nitric oxide synthase (iNOS), and compounds that inhibit NO production have anti-inflammatory effects. In the present study, we systematically investigated the effects of 36 naturally occurring flavonoids and related compounds on NO production in macrophages exposed to an inflammatory stimulus (lipopolysaccharide, LPS), and evaluated the mechanisms of action of the effective compounds. Flavone, the isoflavones daidzein and genistein, the flavonols isorhamnetin, kaempferol and quercetin, the flavanone naringenin, and the anthocyanin pelargonidin inhibited iNOS protein and mRNA expression and also NO production in a dose-dependent manner. All eight active compounds inhibited the activation of nuclear factor-κB (NF-κB), which is a significant transcription factor for iNOS. Genistein, kaempferol, quercetin, and daidzein also inhibited the activation of the signal transducer and activator of transcription 1 (STAT-1), another important transcription factor for iNOS. The present study characterises the effects and mechanisms of naturally occurring phenolic compounds on iNOS expression and NO production in activated macrophages. The results partially explain the pharmacological efficacy of flavonoids as anti-inflammatory compounds.

Nitric Oxide in Inflammation and Immune Response

This short review deals with the role of a recently found signalling molecule, nitric oxide (NO), in inflammatory and immune responses. NO regulates inflammatory erythema and oedema and has cytotoxic action against micro-organisms. In some instances (such as reperfusion injury) NO has cytoprotective properties. Production of large amounts of NO by activated macrophages accounts for their ability to suppress lymphocyte proliferation. NO synthesis in lymphocytes is questionable but cytokines secreted by activated lymphocytes regulate NO synthesis by macrophages. Constitutive NO synthase is activated in neutrophils in response to inflammatory stimuli and NO has diverse, often biphasic effects on neutrophil functions. Increased concentrations of nitrite and nitrate (metabolites of NO) are present in arthritic joints. NO is synthesized not only by migrated inflammatory cells but also by articular chondrocytes and inflamed synovial membrane. In the inflamed joint, NO regulates the synthesis of several inflammatory mediators and functions of inflammatory cells. In addition, NO seems to mediate some destructive effects of proinflammatory cytokines such as interleukin-1. In conclusion, NO regulates several humoral and cellular responses in inflammation, having both anti-inflammatory and proinflammatory properties depending on the type and phase of the inflammatory reaction.

Inhibition by nitric oxide-donors of human polymorphonuclear leucocyte functions.

1 The study was designed to test the hypothesis that nitric oxide (NO)‐releasing compounds increase guanosine 3′:5′‐cyclic monophosphate (cyclic GMP) production in human polymorphonuclear leucocytes (PMNs) and concomitantly inhibit PMN functions, i.e. leukotriene B4 (LTB4) synthesis, degranulation, chemotaxis and superoxide anion (O2−) release. The effects of two new NO‐releasing compounds, GEA 3162 and GEA 5024 were compared to 3‐morpholino‐sydnonimine (SIN‐1) and S‐nitroso‐N‐acetyl‐penicillamine (SNAP). 2 GEA 3162 and GEA 5024 (1–100 μm) inhibited Ca ionophore A23187‐induced LTB4 and β‐glucuronidase release, chemotactic peptide FMLP‐induced chemotaxis and opsonized zymosan‐triggered chemiluminescence dose‐dependently in human PMNs. SIN‐1 and SNAP were weaker inhibitors. 3 Cellular cyclic GMP production was increased after exposure to NO‐donors concomitantly with the inhibition of PMN functions. No alterations in the levels of adenosine 3′:5′‐cylic monophosphate (cyclic AMP) were detected. 4 The results suggest that NO, possibly through increased cyclic GMP, inhibits the activation of human PMNs and may thus act as a local modulator in inflammatory processes.

Leptin enhances synthesis of proinflammatory mediators in human osteoarthritic cartilage--mediator role of NO in leptin-induced PGE2, IL-6, and IL-8 production.

Obesity is an important risk factor for osteoarthritis (OA) in weight-bearing joints, but also in hand joints, pointing to an obesity-related metabolic factor that influences on the pathogenesis of OA. Leptin is an adipokine regulating energy balance, and it has recently been related also to arthritis and inflammation as a proinflammatory factor. In the present paper, the effects of leptin on human OA cartilage were studied. Leptin alone or in combination with IL-1 enhanced the expression of iNOS and COX-2, and production of NO, PGE2, IL-6, and IL-8. The results suggest that the effects of leptin are mediated through activation of transcription factor nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) pathway c-Jun NH2-terminal kinase (JNK). Interestingly, inhibition of leptin-induced NO production with a selective iNOS inhibitor 1400 W inhibited also the production of IL-6, IL-8, and PGE2, and this was reversed by exogenously added NO-donor SNAP, suggesting that the effects of leptin on IL-6, IL-8, and PGE2 production are dependent on NO. These findings support the idea of leptin as a factor enhancing the production of proinflammatory factors in OA cartilage and as an agent contributing to the obesity-associated increased risk for osteoarthritis.

Effects of probiotic therapy on the activity and activation of mild rheumatoid arthritis-a pilot study

Objective: To study the effects of Lactobacillus rhamnosus GG (LGG) on rheumatoid arthritis (RA). Methods: Twenty‐one RA patients were randomised to receive 2 capsules of LGG or a placebo twice daily in double‐blind fashion for 12 months. Arthritis activity was evaluated by clinical examination, HAQ index, and laboratory tests (e.g. ESR, CRP, pro‐ and anti‐inflammatory cytokines). Results: There were no statistical differences in the clinical parameters, biochemical variables and HAQ index between the study groups over the intervention period. The mean number of tender and swollen joints decreased from 8.3 to 4.6 in the Lactobacillus group and from 5.5 to 4.8 in the placebo group (p=0.41). According to the global assessment the RA activity was reduced in 71% (LGG group) vs. 30% (controls) (p=0.15). Serum IL‐1β increased slightly in the LGG group (p=0.07), but no differences were seen in IL‐6, TNF‐α, MPO, IL‐10 or 1L‐12. Conclusions: Although there were no statistical significant differences in the activity of RA, more subjects in the LGG group reported subjective well being. More studies on the effects of probiotic bacteria in RA are needed.

Increased alveolar nitric oxide concentration in asthmatic patients with nocturnal symptoms.

Nocturnal asthma symptoms and impaired lung function at night are related to inflammatory activity in the peripheral lung compartment. Exhaled nitric oxide (NO) measurement at multiple exhalation flow rates can be used to separately assess alveolar and bronchial NO production and inflammation. The authors hypothesised that asthmatic patients with nocturnal symptoms have a higher alveolar NO concentration than those with only daytime symptoms. The authors asked 40 patients with newly-diagnosed steroid-naïve asthma about their nocturnal asthma symptoms through the use of a written questionnaire. Alveolar NO concentration and bronchial NO flux were assessed in the 40 asthmatics and 40 healthy controls. Nineteen of the 40 patients reported nocturnal symptoms. Patients with nocturnal symptoms had a higher alveolar NO concentration (1.7±0.3 (mean±sem) parts per billion (ppb)) than patients without nocturnal symptoms (0.8±0.3 ppb, p=0.012) or healthy controls (1.0±0.1 ppb, p=0.032). Bronchial NO flux was higher both in patients with (2.4±0.4 nL·s−1, p<0.001) and without (2.6±0.4 nL·s−1, p<0.001) nocturnal symptoms, compared to controls (0.7±0.1 nL·s−1). Nocturnal symptoms in asthmatic patients are related to a higher alveolar nitric oxide concentration. The results suggest that assessment of alveolar nitric oxide concentration can be used to detect the parenchymal inflammation in asthmatic patients with nocturnal symptoms.

Breast milk fatty acids, eicosanoids, and cytokines in mothers with and without allergic disease.

Allergic disease (AD), including atopic eczema, asthma, allergic rhinitis, and food allergy, is characterized by an imbalance between cytokines produced by distinct T-helper cell subtypes. Whether this imbalance can be transferred from mother to breast milk remains to be established. The objective was to investigate the concentrations and interactions of nutritional and inflammatory factors in breast milk. Breast milk samples were collected from mothers with AD (n = 43) and without AD (n = 51). The concentrations of transforming growth factor (TGF)-β2, tumor necrosis factor-α, IL-4, IL-10, prostaglandin E2, and cysteinyl leukotrienes were measured by immunoassays and fatty acid composition by gas chromatography. Mothers with AD had a lower concentration of TGF-β2 in breast milk [median (interquartile range), 420 (278–701) ng/L] compared with those without AD [539 (378–1108) ng/L;p = 0.003], whereas other cytokines, prostaglandin E2, and cysteinyl leukotriene concentrations or fatty acid composition were not significantly different between the groups. The breast milk inflammatory factors and fatty acid composition were shown to be related. A positive association was observed between TGF-β2 and the proportion of polyunsaturated fatty acids (p = 0.038) and a negative association between TGF-β2 and the proportion of saturated fatty acids (p = 0.029) in breast milk. The reduced TGF-β2 concentration in the breast milk of mothers with AD may interfere with the development of the mucosal immune system of the breast-fed infant. The observed associations between nutritional and inflammatory factors in breast milk suggest that it may be possible to influence the immunologic properties of breast milk by dietary intervention of the mother.

Inhaled fluticasone decreases bronchial but not alveolar nitric oxide output in asthma

Exhaled nitric oxide (NO) concentration is a noninvasive measure of airway inflammation and is increased in asthma. Inhaled glucocorticoids decrease exhaled NO concentration, but the relative contributions of alveolar and bronchial levels to the decrease in exhaled NO concentration are unknown. Alveolar NO concentration and bronchial NO flux can be separately approximated by measuring exhaled NO at several exhalation flow rates. The effect of steroid treatment on alveolar and bronchial NO output in asthma was studied. Alveolar NO concentration and bronchial NO flux were assessed in 16 patients with asthma before and during treatment with inhaled fluticasone for 8 weeks and in 16 healthy controls. Before the treatment, asthmatics had increased bronchial NO flux (mean+/-SEM: 3.6+/-0.4 versus 0.7+/-0.1 nL x s(-1), p<0.001) but normal alveolar NO concentration (1.2+/-0.5 versus 1.0+/-0.2 parts per billion (ppb), p>0.05) compared with controls. Inhaled fluticasone decreased bronchial NO flux from 3.6+/-0.4 to 0.7+/-0.1 nL x s(-1) (p<0.01) but had no effect on alveolar NO concentration (before: 1.2+/-0.5; after: 1.2+/-0.1 ppb, p>0.05). The forced expiratory volume in one second improved, whereas asthma symptom score and serum levels of eosinophil cationic protein and eosinophil protein X decreased during the treatment. In conclusion, inhaled fluticasone decreases bronchial but not alveolar nitric oxide output simultaneously with clinical improvement in patients with asthma.

ANTI-INFLAMMATORY ACTIVITIES OF EMBLICA OFFICINALIS GAERTN LEAF EXTRACTS

Abstract— Emblica officinalis Gaertn, a tree growing in subtropical and tropical parts of China, India, Indonesia and the Malay Peninsula, has been used for anti‐inflammatory and antipyretic treatments of rural populations in these areas. In the present study, we examined the effects of Emblica officinalis extracts on carrageenan‐ and dextran‐induced rat hind paw oedema. Anti‐inflammatory activity was found in the water fraction of methanol extract of the plant leaves. The effects of the same fraction were tested on the synthesis of mediators of inflammation such as leukotriene B4 (LTB4), platelet‐activating factor (PAF) and thromboxane B2 (TXB2), and on LTB4‐ and N‐formyl‐l‐methionyl‐l‐leucyl‐l‐phenylalanine (FMLP)‐induced migration of human polymorphonuclear leucocytes (PMNs) in‐vitro. The water fraction of the methanol extract inhibited migration of human PMNs in relatively low concentrations. It did not inhibit LTB4 or PAF synthesis in human PMNs or TXB2 synthesis in human platelets during clotting, suggesting that the mechanism of the anti‐inflammatory action found in the rat paw model does not involve inhibition of the synthesis of the measured lipid mediators.