Sodium houttuyfonate inhibits LPS-induced inflammatory response via suppressing TLR4/NF-ĸB signaling pathway in bovine mammary epithelial cells.

Mastitis is an inflammatory reaction caused by microorganisms in the mammary gland which usually leads to the decrease of the dairy production. It vastly makes bad effect on the cattle industry all over the world. Nowadays, an increasing number of scientists keep a watchful eye on natural compounds to prevent mastitis. Sodium houttuyfonate (SH) has been reported to have antibacterial and anti-inflammatory effects. This experiment aimed to investigate the anti-inflammatory properties of SH on LPS-stimulated primary bovine mammary epithelial cells (bMEC). The effects of SH on TNF-α, IL-1ß, and IL-6 production were detected by qRT-PCR. Western blot analysis was used for detecting the effects of SH on TLR4/NF-κB signal pathways. The results showed that SH significantly inhibited LPS-stimulated TNF-α, IL-1ß and IL-6 production. Furthermore, SH significantly inhibited LPS-induced TLR4 expression and NF-ĸB activation. In summary, these results suggested that SH inhibited LPS-induced inflammatory response by inhibiting TLR4/NF-ĸB signaling pathway. SH is a potential agent for the treatment of mastitis.

Induction of omega 6 inflammatory pathway by sodium metabisulfite in rat liver and its attenuation by ghrelin.

BACKGROUND: Sodium metabisulfite is commonly used as preservative in foods but can oxidize to sulfite radicals initiating molecular oxidation. Ghrelin is a peptide hormone primarily produced in the stomach and has anti-inflammatory effects in many organs. This study aimed to assess endogenous omega-3 (n-3) and omega-6 (n-6) polyunsaturated fatty acids (PUFAs) in rat peripheral organs following sodium metabisulfite treatment and determine the possible effect of ghrelin on changes in n-6 inflammatory pathway. METHODS: Male Wistar rats included in the study were allowed free access to standard rat chow. Sodium metabisulfite was given by gastric gavage and ghrelin was administered intraperitoneally for 5 weeks. Levels of arachidonic acid (AA, C20:4n-6), dihomo-gamma-linolenic acid (DGLA, C20:3n-6), eicosapentaenoic acid (EPA, C20:5n-3) and docosahexaenoic acid (DHA, C22:6n-3) in liver, heart and kidney tissues were determined by an optimized multiple reaction monitoring (MRM) method using ultra fast-liquid chromatography (UFLC) coupled with tandem mass spectrometry (MS/MS). Cyclooxygenase (COX) and prostaglandin E2 (PGE2) were measured in tissue samples to evaluate changes in n-6 inflammatory pathway. RESULTS: Omega-6 PUFA levels, AA/DHA and AA/EPA ratio were significantly increased in liver tissue following sodium metabisulfite treatment compared to controls. No significant change was observed in heart and kidney PUFA levels. Tissue activity of COX and PGE2 levels were also significantly increased in liver tissue of sodium metabisulfite treated rats compared to controls. Ghrelin treatment decreased n-6 PUFA levels and reduced COX and PGE2 levels in liver tissue of sodium metabisulfite treated rats. CONCLUSION: Current results suggest that ghrelin exerts anti-inflammatory action through modulation of n-6 PUFA levels in hepatic tissue.

Ghrelin inhibits sodium metabisulfite induced oxidative stress and apoptosis in rat gastric mucosa.

This study aimed to investigate the effect of ghrelin administration on sulfite induced oxidative and apoptotic changes in rat gastric mucosa. Forty male albino Wistar rats were randomized into control (C), sodium metabisulfite (Na2S2O5) treated (S), ghrelin treated (G) and, Na2S2O5+ghrelin treated (SG) groups. Sodium metabisulfite (100 mg/kg/day) was given by gastric gavage and, ghrelin (20 µg/kg/day) was given intraperitoneally for 5 weeks. Plasma-S-sulfonate level was increased in S and SG groups. Na2S2O5 administration significantly elevated total oxidant status (TOS) levels while depleting total antioxidant status (TAS) levels in gastric mucosa. Ghrelin significantly decreased gastric TOS levels in the SG group compared with the S group. Additionally, TAS levels were found to be higher in SG group in reference to S group. Na2S2O5 administration also markedly increased the number of apoptotic cells, cleaved caspase-3 and PAR expression (PARP activity indicator) and, decreased Ki67 expression (cell proliferation index) in gastric mucosal cells. Ghrelin treatment decreased the number apoptotic cells, cytochrome C release, PAR and, caspase-3 expressions while increasing Ki67 expression in gastric mucosa exposed to Na2S2O5. In conclusion, we suggest that ghrelin treatment might ameliorate ingested-Na2S2O5 induced gastric mucosal injury stemming from apoptosis and oxidative stress in rats.

The effect of sodium metabisulfite on visual evoked potentials in rats with hypercholesterolemia.

This study aimed to investigate the effects of hypercholesterolemia on visual evoked potentials (VEPs) and sulfite additional effects. Rats were assigned as follows: control (C), sulfite (S), hypercholesterolemia (H), vitamin E (E), sulfite + vitamin E (SE), hypercholesterolemia + sulfite (HS), hypercholesterolemia + vitamin E (HE), and hypercholesterolemia + sulfite + vitamin E (HSE). Hypercholesterolemic diet led significant increase in plasma cholesterol levels of rats. Brain thiobarbituric acid reactive substances (TBARS) levels were significantly increased in S, E, SE, HE and HSE groups compared with C. TBARS levels were increased in HE and HSE groups as compared to HS group. Nitrite levels were decreased in S, SE, H, HS and HSE groups compared with C. Nitrite level was notably increased in the HE group compared with H group. Sulfite exposure prolonged N1 and P3 latencies of VEP in group S compared with C. Prolonged VEP latencies by sulfite were significantly decreased by vitamin E in SE group. Cholesterol rich diet increased VEP latencies in comparison with control latencies. Sulfite gave rise to an additional increase in P3 latency in HS group compared with H group. Vitamin E-treated animals had notably shortened latencies of VEP components in HE and HSE groups according to the H and HS groups, respectively.

Epigallocatechin-3-gallate protects Na+ channels in rat ventricular myocytes against sulfite.

Sulfite (bisulfite/sulfite) can affect voltage-gated sodium (Na(+)) channels (VGSC) in a concentration-dependent manner in isolated rat ventricular myocytes. In this study, the effect of epigallocatechin-3-gallate (EGCG) on VGSC in isolated ventricular myocytes was studied. Ventricular myocytes were exposed to 10 microM bisulfite/sulfite for 10 min, and EGCG was then administered in different concentrations (10, 30, 50 microg ml(-1)). Decreased activity of superoxide dismutase, catalase (CAT) and glutathione peroxidase (GPx) was observed after bisulfite/sulfite exposure, with significant increase in Na(+) currents (I (Na)) and alterations in half-activation voltage and half-inactivation voltage. Intracellular reactive oxygen species (ROS) such as hydrogen peroxide (H(2)O(2)), hydroxyl (OH(.)), and superoxide anion (O (2) (.-) ) were increased. After EGCG treatment, activity of the aforementioned enzymes increased while the ROS level decreased. The effects progressed with increasing amounts of EGCG, up to a level similar to blank control at the dose of 50 microg ml(-1) EGCG, EGCG also reduced the I (Na) and reversed the alterations in half-activation voltage and half-inactivation voltage. In conclusion, EGCG could protect Na(+) channels in rat ventricular myocytes against the oxidative damage induced by sulfite as a scavenger of the ROS.

Sulfite is generated from PAPS by activated neutrophils.

We previously reported that neutrophils produce sulfite in response to stimulation with lipopolysaccharide, and sulfite production is dependent on inorganic sulfate contained in culture media. Microorganisms such as yeast assimilate sulfate, during which process sulfite is generated by reduction of 3'-phosphoadenosine 5'-phosphosulfate (PAPS), an activated sulfate donor. However, little is known about how sulfite is produced in mammalian cells. In the current study, we demonstrated that chlorate, a specific inhibitor for PAPS synthesis, significantly suppressed production of sulfite by activated neutrophils obtained from rat peritoneal cavity that had been injected with glycogen to induce inflammation. Addition of excess amounts of PAPS could partially overcome the inhibitory effect of chlorate. Moreover, sulfite production from PAPS was clearly demonstrated in the cytosolic fraction of activated neutrophils. These findings strongly suggest that sulfite is generated, at least in part, from PAPS by activated neutrophils.

Sulfite and membrane energization induce two different active states of the Paracoccus denitrificans F0F1-ATPase.

Activation of the latent ATPase activity of inside-out vesicles from plasma membranes of Paracoccus denitrificans was studied. Several factors were found to induce activation: heat, membrane energization by succinate oxidation, methanol, oxyanions (sulfite, phosphate, arsenate, bicarbonate) and limited proteolysis with trypsin. Among the oxyanions, sulfite induced the higher increase in ATPase activity. Sulfite functioned as a nonessential activator that slightly modified the affinity for ATP and increased notoriously the Vmax. There was a competitive effect between sulfite, bicarbonate and phosphate for ATPase activation; their similar chemical geometry suggests that these oxyanions have a common binding site on the enzyme. Dithiothreitol did not affect the ATPase activity. ATPase activation by sulfite was decreased by uncoupler, enhanced by trypsin and inhibited by ADP, oligomycin and venturicidin. In contrast, activation induced by succinate was less sensitive to ADP, oligomycin, venturicidin and trypsin. It is proposed that the active states induced by sulfite and succinate reflect two conformations of the enzyme, in which the inhibitory subunit epsilon is differently exposed to trypsin.

Enhancement of the growth of Helicobacter pylori in Brucella broth by hydrogen peroxide.

We found that a sub-lethal concentration of hydrogen peroxide (HPOx) enhanced the growth of Helicobacter pylori in Brucella broth supplemented with 10% fetal bovine serum (BB/FBS). The enhancement was evident at 0.1 mM HPOx and reached a maximun at 3.5 mM. The growth stimulation was dependent on the basal media used; when brain heart infusion broth (BHIB) was used instead of BB, the growth was not altered regardless of the presence or absence of HPOx. Furthermore, the growth in BHIB/FBS was comparable to that in BB/FBS plus 3.5 mM HPOx. This suggested that the enhancement of growth by HPOx resulted from the derepression of the inhibitory factor existing in BB by HPOx. The inhibitory substance seemed to be bisulfite salt since the bacteria grew to a similar extent in bisulfite-less Brucella broth (BLBB0)/FBS compared to the bacterial growth in BHIB/FBS and BB/FBS plus HPOx. These results indicate that the detoxification of bisulfite in BB can be easily achieved by simply adding HPOx to the medium, which causes the oxidation of bisulfite to bisulfate, a less-toxic compound to the bacterial growth. Since we also found that the morphology and cellular protein profile of BB/FBS-cultured bacteria were apparently different from those cultured in BLBB/FBS, we propose that the use of BB for primary isolation and cultivation of H. pylori should be limited on certain occasions, or if necessary, BB can be used after detoxification of the bisulfite by the addition of a low concentration of HPOx.

Effect of acetazolamide and amiloride against sodium metabisulphite-induced bronchoconstriction in mild asthma.

BACKGROUND: Inhaled frusemide but not bumetanide, another loop diuretic, reduces bronchial responsiveness to sodium metabisulphite (MBS). To investigate whether the effect of frusemide could be mediated through mechanisms other than Na+/K+/Cl- cotransporter inhibition, the effects of amiloride--an inhibitor of sodium channels in the airway epithelium--and of acetazolamide--a specific inhibitor of carbonic anhydrase--against MBS challenge were studied. METHODS: In two separate randomised double blind placebo controlled studies, 10 subjects with mild asthma attended on four separate occasions to inhale 7.5 mg amiloride or matched placebo, and 500 mg acetazolamide or placebo, immediately before MBS challenge. The concentration of MBS required to cause a 20% fall in baseline FEV1 (PC20) was measured. RESULTS: Amiloride and acetazolamide had no effect on baseline FEV1. Amiloride had no effect against MBS challenge, but acetazolamide increased -log PC20 from a mean (SE) of 0.75 (0.09) to 0.98 (0.06) representing a 0.77 (0.24) doubling dose increase. CONCLUSIONS: These results suggest that carbonic anhydrase activity in the airways, but not sodium flux, modulates bronchial responsiveness to MBS challenge. The action of frusemide is not likely to involve inhibition of carbonic anhydrase activity.

Inhibition of sodium metabisulphite induced bronchoconstriction by frusemide in asthma: role of cyclooxygenase products.

BACKGROUND: Inhaled frusemide inhibits airway responses to sodium metabisulphite and other indirect bronchial challenges in asthma by undetermined mechanisms which may relate to its ability to stimulate prostaglandin release. Inhalation of sodium metabisulphite provokes indirect bronchoconstriction, possibly by activating sensory nerves. To investigate the role of cyclooxygenase products in the airway actions of frusemide and sodium metabisulphite, the effects of a potent cyclooxygenase inhibitor, flurbiprofen, alone and in combination with frusemide were investigated against airway responsiveness to sodium metabisulphite. METHODS: In a double blind double placebo controlled study, 12 mild asthmatic subjects attended on four occasions to undergo three inhalation challenges with sodium metabisulphite. A baseline challenge was performed one hour before oral intake of flurbiprofen 200 mg or matched placebo, and two hours before inhalation of frusemide 40 mg or matched placebo. A second challenge was performed immediately after inhalation of frusemide (two hours after flurbiprofen) with a further challenge three hours later. The log concentration provoking a 20% fall in FEV1 (log PC20) was used to assess airway responsiveness to sodium metabisulphite. RESULTS: Frusemide caused an immediate 1.9 doubling dose protection and a lesser 0.7 doubling dose protection at three hours. This protection was enhanced by flurbiprofen at both time points to 2.7 (early) and 1.9 (late) doubling doses. In addition, flurbiprofen alone significantly reduced airway responsiveness to sodium metabisulphite by 1.1 doubling doses at both two and five hours. CONCLUSIONS: The generation of bronchoprotective prostaglandins is unlikely to underlie the inhibitory action of frusemide against airway responsiveness to sodium metabisulphite. Endogenous contractile prostaglandins within the airways may be involved in the bronchoconstrictor response to sodium metabisulphite.

Protective effect of loop diuretics, piretanide and frusemide, against sodium metabisulphite-induced bronchoconstriction in asthma.

We determined whether the loop diuretic, piretanide, had a similar inhibitory action against sodium metabisulphite (MBS)-induced bronchoconstriction in asthmatic subjects as frusemide and, if so, its duration of action. In the first study, we compared the effect of inhaled placebo, piretanide (24 mg), or frusemide (40 mg), on the provocative concentration of MBS needed to cause a 20% fall in baseline forced expiratory volume in one second (FEV1) (PC20MBS) in 12 mild asthmatic subjects before, immediately after, and at 1.5, 3, 6, and 24 h, after inhalation. Both piretanide and frusemide induced a significant diuresis lasting at least 24 h. Frusemide caused a mean 3.8 fold (95% confidence interval: 2.3-6.3 fold), piretanide a 2.5 fold (1.8-3.4 fold) and placebo a 1.7 fold (1.5-1.9 fold) increase in PC20MBS. The effects of frusemide and piretanide were significantly greater than that of placebo. At later time points, tachyphylaxis to the bronchoconstrictor effects of MBS was observed during the placebo limb. In the second study, we measured PC20MBS at 90 min after inhalation of either placebo, piretanide (24 mg), or frusemide (40 mg). No significant difference in PC20MBS was observed. We conclude that piretanide in addition to frusemide significantly inhibits MBS-induced bronchoconstriction and that this action is short-lived over less than 90 min. Frusemide was more potent in inhibiting MBS-induced bronchoconstriction despite causing a smaller diuretic effect than piretanide. The basic mechanism of action of the loop diuretics in the airways remains unclear.

The effect of amiloride on the airway response to metabisulphite in asthma: a negative report.

Frusemide, a loop diuretic, has been shown to potently inhibit several indirect bronchoconstrictor challenges in asthma. The mechanism by which nebulized frusemide protects against indirect bronchoconstrictor stimuli in asthma is not known. One mechanism could be related to inhibition of sodium transport. If this is the case, then amiloride, another inhibitor of sodium transport, should also protect against indirect bronchoconstrictor challenges. Ten subjects with mild asthma were administered either 10(-2) M amiloride or placebo, by nebulizer, in a double-blind crossover fashion. After each inhalation, forced expiratory volume in one second (FEV1) was recorded at 10 min intervals for 30 min, after which a metabisulphite challenge was performed. No significant difference in the response to metabisulphite was seen between placebo and amiloride treatment. The mean difference in provocative dose of metabisulphite producing a 20% fall in FEV1 (PD20) between placebo and amiloride was 1.015 doubling doses, 95% confidence interval (95% CI) -0.201 to 2.231, (p = 0.09). This result does not support the hypothesis that frusemide is acting to protect against bronchoconstrictor challenges in asthma by an effect on sodium transport.

Inhibition of inhaled metabisulphite-induced bronchoconstriction by inhaled frusemide and ipratropium bromide.

1. The effect of inhaled frusemide and high dose inhaled ipratropium bromide on bronchoconstriction induced by inhaled metabisulphite was studied in 10 atopic volunteers. 2. Frusemide (40 mg), ipratropium bromide (0.5 mg) or saline placebo were administered by nebuliser in a double-blind fashion, prior to construction of a dose-response curve to metabisulphite (2.5-100 mg ml-1). 3. Geometric mean of the provocative dose of metabisulphite that caused a 35% fall in specific airways resistance (sGaw) after placebo was 13 (95% confidence intervals CI 4-36 mumol) compared with 36 (16-78) mumol after ipratropium bromide and 45 (22-94) mumol after frusemide. 4. Mean maximum fall in sGaw was 49 (40-57)% after placebo, 11 (0-22)% after frusemide and -1 (-25-22)% after ipratropium bromide. 5. Frusemide significantly protected against metabisulphite induced bronchoconstriction (P less than 0.005). The protection from high dose ipratropium bromide was also significant (P less than 0.05), but the response was more variable between subjects.

Asthma with sulfite intolerance in children: a blocking study with cyanocobalamin.

Sulfites have been implicated as the cause of bronchospasm in some subjects with asthma. However, there is still no universally accepted explanation of the pathogenesis of these reactions. We have studied five children with asthma with metabisulfite intolerance confirmed by oral challenge testing. The challenge test with metabisulfite was repeated after premedication of all the patients with 1.5 mg of oral cyanocobalamin. In four of the five patients treated with cyanocobalamin, bronchospasm did not develop in the second metabisulfite challenge. The possible mechanisms are discussed.

Effect of neutral endopeptidase inhibitor on airway function and bronchial responsiveness in asthmatic subjects.

We determined the effect of an inhibitor of neutral endopeptidase, acetorphan, on the skin responses to substance P and on the bronchostrictor effects of sodium metabisulphite aerosol in asthmatic subjects. One hour following ingestion of acetorphan (200 mg) or placebo tablets, cutaneous responses to substance P were performed in four subjects. In seven subjects, bronchial challenge with increasing concentrations of sodium metabisulphite solutions was performed and the concentration required to cause a 20% fall in baseline FEV1 determined (PC20). On the acetorphan day, there was a significant increase in the wheal and flare responses to substance P and to the diluent (0.9% NaCl) alone. However, there was no significant effect of acetorphan on the PC20 metabisulphite. We conclude that metabisulphite airway challenge in vivo may not invoke the release of endogenous neuropeptides. However, the degree of inhibition of neuropeptide breakdown by the oral dose of acetorphan used may not have been optimal.

Salbutamol inhibits metabisulphite-induced bronchoconstriction.

The effect of salbutamol on bronchoconstriction induced by inhaled sodium metabisulphite has been studied in 12 atopic subjects. Salbutamol (200 micrograms, 3.5 x 10(-7) M) and matched placebo were administered by identical metered dose inhaler 15 min before a dose-response to sodium metabisulphite (1.25-100 mg ml-1) was performed. Geometric mean provocative dose of metabisulphite causing a 35% fall in sGaw after placebo pretreatment was 12.8 [5.75-28.1, 95% Cl] mumol, and after salbutamol was 75.9 [46.5-126] mumol. Mean maximum fall in sGaw after placebo pre-treatment was 47.4 [41-53.9]%. At the same metabisulphite concentration mean maximum fall in sGaw after salbutamol was 2.9 [-8.2-14.1]%.

Effect of inhaled prostaglandin E2 on bronchial reactivity to sodium metabisulphite and methacholine in patients with asthma.

Inhaled frusemide protects against the bronchoconstrictor response to a wide range of stimuli that cause bronchoconstriction by indirect mechanisms. One possible explanation for this protection relates to the known ability of frusemide to enhance synthesis of prostaglandin E2 (PGE2). Studies in vitro suggest that PGE2 might protect against indirectly acting bronchoconstrictor challenges rather than those that act directly on airway smooth muscle, though little is known about the effects of PGE2 in vivo. The effect of inhaled PGE2 on the bronchoconstrictor response to inhaled sodium metabisulphite (a stimulus with an indirect action) and methacholine (which acts directly on airway smooth muscle) was studied in nine patients with asthma. Subjects were studied on four days, inhaling PGE2 (100 micrograms) or placebo in a double blind fashion followed immediately by a cumulative dose challenge with sodium metabisulphite or methacholine. The response to the constrictor stimuli was measured as the provocative dose causing a 20% fall in FEV1 (PD20). There was no significant change in FEV1 after inhaled PGE2 compared with placebo, nor any significant change in the response to methacholine; the geometric mean methacholine PD20 was 0.9 mumol after PGE2 and 0.56 mumol after placebo (mean difference 0.7 (95% confidence limits--0.1, 1.5) doubling doses). PGE2, however, protected against sodium metabisulphite, the geometric mean sodium metabisulphite PD20 being 11.8 mumol after PGE2 and 1.8 mumol after placebo (mean difference 2.5 (95% CL 1.9, 3.1) doubling doses). PGE2 conferred significantly greater protection against sodium metabisulphite than methacholine (mean difference 1.8 (95% CL 0.8, 2.8) doubling doses). This suggests that PGE2, like frusemide, has an inhibitory effect on pathways relevant to the bronchoconstriction induced by sodium metabisulphite, with little or no effect on those relevant to methacholine.

Inhaled sodium metabisulphite induced bronchoconstriction: inhibition by nedocromil sodium and sodium cromoglycate.

1. The effects of nedocromil sodium and sodium cromoglycate on bronchoconstriction induced by inhaled sodium metabisulphite have been studied in eight atopic subjects, three of whom had mild asthma. 2. Nedocromil sodium (4 mg, 7.8 X 10(-6) M), sodium cromoglycate (10 mg, 24.1 X 10(-6) M) and matched placebo were administered by identical metered dose inhalers 30 min before a dose-response to sodium metabisulphite (5-100 mg ml-1) was performed. 3. Maximum fall in sGaw after placebo pre-treatment was -43.9 +/- 3.3% baseline (mean +/- s.e. mean). At the same metabisulphite concentration maximum fall in sGaw after sodium cromoglycate was -13.0 +/- 3.6% and after nedocromil sodium was +4.3 +/- 6.8%. Nedocromil sodium prevented any significant fall in sGaw even after higher concentrations of metabisulphite. 4. Both nedocromil sodium, 4 mg, and sodium cromoglycate, 10 mg, inhibited sodium metabisulphite induced bronchoconstriction but nedocromil sodium was significantly more effective. Relative in vivo potency of the two drugs is broadly in line with other in vivo and in vitro studies.

Bronchoconstriction by nebulized metabisulfite solutions (SO2) and its modification by ipratropium bromide.

A nebulized solution of sodium metabisulfite (MBS) induced bronchoconstriction in nine subjects with asthma. An anticholinergic drug, ipratropium bromide (IPRA), in doses (500 to 700 micrograms) which were found to inhibit methacholine-induced bronchoconstriction, protected three of the nine subjects against nebulized MBS. These results suggest that both cholinergic and non-cholinergic reflex mechanisms are involved in MBS-induced bronchoconstriction.