Methionine supplementation for multi-organ dysfunction in MetRS-related pulmonary alveolar proteinosis.

INTRODUCTION: Pulmonary alveolar proteinosis related to mutations in the methionine tRNA synthetase (MARS1) gene is a severe, early-onset disease that results in death before the age of 2 years in one-third of patients. It is associated with a liver disease, growth failure and systemic inflammation. As methionine supplementation in yeast models restored normal enzymatic activity of the synthetase, we studied the tolerance, safety and efficacy of daily oral methionine supplementation in patients with severe and early disease. METHODS: Four patients received methionine supplementation and were followed for respiratory, hepatic, growth and inflammation-related outcomes. Their course was compared to those of historical controls. Reactive oxygen species production by patient monocytes before and after methionine supplementation was also studied. RESULTS: Methionine supplementation was associated with respiratory improvement, clearance of the extracellular lipoproteinaceous material and discontinuation of whole-lung lavage in all patients. The three patients who required oxygen or noninvasive ventilation could be weaned off within 60 days. In addition, liver dysfunction, inflammation and growth delay improved or resolved. At a cellular level, methionine supplementation normalised the production of reactive oxygen species by peripheral monocytes. CONCLUSION: Methionine supplementation was associated with important improvements in children with pulmonary alveolar proteinosis related to mutations in the MARS1 gene. This study paves the way for similar strategies for other tRNA synthetase deficiencies.

Syzygium aromaticum aqueous extract inhibits human neutrophils myeloperoxidase and protects mice from LPS-induced lung inflammation.

CONTEXT: Syzygium aromaticum (L.) Merr. & Perry (Myrtaceae), commonly known as clove, originally found in the Muluku Islands in East Indonesia, is widely used as a spice and has numerous medicinal properties. OBJECTIVE: This study investigated the antioxidant potential of S. aromaticum aqueous extract (SAAE) in vitro and its protective effects on lipopolysaccharide (LPS)-induced lung inflammation in mice. MATERIAL AND METHODS: Neutrophils were isolated from healthy donors and reactive oxygen species (ROS) generation was measured by luminol-amplified chemiluminescence. Superoxide anion generation was detected by cytochrome c reduction assay. H2O2 was detected by DCFH fluorescence assay. Myeloperoxidase (MPO) activity was mesured by tetramethyl benzidine oxidation method. To study the anti-inflammatory activity of SAAE, lung inflammation was induced in mice (BALB/c) by intra-tracheal instillation of lypopolysaccharide (5 µg/mouse), and SAAE (200 mg/kg body weight) was injected intraperitoneally prior to LPS administration. Bronchoalveolar lavage and lung tissue were collected to assess inflammatory cells count and total protein content. Metalloproteinases activity was detected by zymography technique. RESULTS: SAAE inhibited luminol-amplified chemiluminescence of resting neutrophils and N-formyl-methionyl-leucyl-phenylalanine- or phorbol myristate acetate-stimulated neutrophils, with an inhibitory effect starting at a concentration as low as 0.5 µg/mL. Moreover, SAAE reduced significantly MPO activity and it exhibits a dose-dependent action (IC50 = 0.5 µg/mL). In vivo results showed that SAAE decreased markedly neutrophil count (From 61% to 15%) and proteins leakage into bronchoalveolar lavage fluid. Gelatin zymography assay showed that S. aromaticum inhibited MMP-2 (15%) and MMP-9 (18%) activity in lung homogenates. DISCUSSION AND CONCLUSION: Our results suggest that the anti-inflammatory activity of SAAE, in vivo, is due to the inhibition of ROS production and metalloproteinases activity via its action on MPO. According to these findings, SAAE could be a potential source of new compounds with anti-inflammatory activity.

Chemical constituents and pharmacological actions of carob pods and leaves (Ceratonia siliqua L.) on the gastrointestinal tract: A review.

Carob tree, Ceratonia siliqua L., is a medicinal plant used in Tunisian traditional medicine for the treatment of the gastro-intestinal (GI) disorders. In this respect, a relatively large number of scientific publications on the carob tree have been published in recent years. Therefore, the present review was aimed to analyze the traditional uses, phytochemical constituents and pharmacological activities of Ceratonia siliqua on the GI tract. Indeed, previous investigations on the carob pods and leaves have revealed the presence of a number of compounds including high amounts of carbohydrates, dietary fibers, minerals, polyphenols, flavonoids and low amounts of protein and lipids. This plant possesses anti-inflammatory, antimicrobial, anti-diarrheique, antioxidant, anti-ulcer, anti-constipation and anti-absorptive of glucose activities in the gastrointestinal tract. Based on the chemical and pharmacological characteristics of C. siliqua, we concluded that this species has beneficial preventive and therapeutic properties, especially, in digestive tract.

Anvillea garcinii extract inhibits the oxidative burst of primary human neutrophils.

BACKGROUND: Anvillea garcinii Coss. & Durieu (Anv) plant is used as a traditional North African medicine against several diseases associated with inflammation. At inflammatory sites, reactive oxygen species (ROS) produced in excess by activated phagocyte NADPH oxidase (NOX2) can accentuate inflammatory responses. Thus, we investigated if Anv-water soluble polysaccharides could modulate primary human neutrophil oxidative burst in vitro. METHODS: Human neutrophils were isolated from fresh whole blood and O2.- generation was measured by cytochrome c reduction assays. Western blots were used to analyse the translocation of PKC, p47phox (a key component of NOX2 activity) to neutrophil plasma membrane. Also, myeloperoxidase (MPO) release in the extracellular medium was studied by western blots. Flow cytometric analysis was used to detect CD11b membrane expression. RESULTS: Water soluble polysaccharides from Anv dose-dependently inhibited N-formyl-methionyl-leucyl-phenylalanine (fMLF)- and phorbol myristate acetate (PMA)-induced O2.- generation by human neutrophils. Moreover, Anv-polysaccharides strongly inhibited PMA-induced PKCß and p47phox translocation to membranes and p47phox phosphorylation on Ser328, a main PKC target. In contrast, polysaccharides extract from Zygophyllum gaetulum plant, which is also used as a traditional North African medicine against inflammatory diseases, was ineffective on this PKCß-p47phox pathway. Further, Anv inhibited important neutrophil degranulation markers corresponding to myeloperoxidase (MPO) release and CD11b membrane expression. CONCLUSION: The process of down-regulating NADPH oxidase by polysaccharides extracts from Anv provides new insights into the mechanism of Anv's anti-inflammatory actions.

Protective Effect of Ceratonia siliqua L. Against a Dextran Sulfate Sodium-Induced Alterations in Liver and Kidney in Rat.

The aim of the present study is to investigate the potential protective role of Ceratonia siliqua L. against dextran sodium sulfate (DSS)-induced oxidative damage and inflammation in liver and kidney of rats. The hepatotoxicity and nephrotoxicity were induced in rats by oral administration of synthetic DSS (5%) in the drinking water for over 7 days. However, carob pods aqueous extract (CPAE; 50 and 100 mg/kg body weight) was given by oral administration for 21 days. Myeloperoxidase (MPO) activity, malondialdehyde, H2O2 content, as well as the levels of antioxidant enzymes in organs were measured to observe the possible mechanisms. As a result, the CPAE counteracted DSS-induced increase of MPO activity, lipoperoxidation, and the activity of antioxidant enzymes, such as superoxide dismutase and catalase (CAT). DSS administration increased also in the organs hydrogen peroxide (H2O2) and free iron levels, whereas the CPAE pretreatment reversed all intracellular mediator perturbations. It was concluded that the CPAE exerted a potential protective effect against DSS-induced inflammation and oxidative stress in the rat organs. Consequently, it is essential that adequate care is taken when we use carob pods for patients with hepatotoxicity and nephrotoxicity.

Chamomile decoction extract inhibits human neutrophils ROS production and attenuates alcohol-induced haematological parameters changes and erythrocytes oxidative stress in rat.

BACKGROUND: The aim of this study was to evaluate the protective effects of subacute pre-treatment with chamomile (Matricaria recutita L.) decoction extract (CDE) against stimulated neutrophils ROS production as well as ethanol (EtOH)-induced haematological changes and erythrocytes oxidative stress in rat. METHODS: Neutrophils were isolated and ROS generation was measured by luminol-amplified chemiluminescence. Superoxide anion generation was detected by the cytochrome c reduction assay. Adult male wistar rats were used and divided into six groups of ten each: control, EtOH, EtOH + various doses of CDE (25, 50, and 100 mg/kg, b.w.), and EtOH+ ascorbic acid (AA). Animals were pre-treated with CDE extract during 10 days. RESULTS: We found that CDE inhibited (P ≤ 0.0003) luminol-amplified chemiluminescence of resting neutrophils and N-formyl methionylleucyl-phenylalanine (fMLF) or phorbolmyristate acetate (PMA) stimulated neutrophils, in a dose-dependent manner. CDE had no effect on superoxide anion, but it inhibited (P ≤ 0.0004) H2O2 production in cell free system. In vivo, CDE counteracted (P ≤ 0.0034) the effect of single EtOH administration which induced (P < 0.0001) an increase of white blood cells (WBC) and platelets (PLT) counts. Our results also demonstrated that alcohol administration significantly (P < 0.0001) induced erythrocytes lipoperoxidation increase and depletion of sulfhydryl groups (-SH) content as well as antioxidant enzyme activities as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). More importantly, we found that acute alcohol administration increased (P < 0.0001) erythrocytes and plasma hydrogen peroxide (H2O2), free iron, and calcium levels while the CDE pre-treatment reversed increased (P ≤ 0.0051) all these intracellular disturbances. CONCLUSIONS: These findings suggest that CDE inhibits neutrophil ROS production and protects against EtOH-induced haematologiacal parameters changes and erythrocytes oxidative stress. The haematoprotection offered by chamomile might involve in part its antioxidant properties as well as its opposite effect on some intracellular mediators such as H2O2, free iron, and calcium.

Gastroprotective effect of carob (Ceratonia siliqua L.) against ethanol-induced oxidative stress in rat.

BACKGROUND: We aimed in the present study, at investigating the gastroprotective effect of carob pods aqueous extract (CPAE) against ethanol-induced oxidative stress in rats as well as the mechanism implicated. METHODS: Adult male wistar rats were used and divided into six groups of ten each: control, EtOH (80% v/v, 4 g/kg b.w.), EtOH 80% + various doses of CPAE (500, 1000 and 2000 mg/kg, b.w.) and EtOH + Famotidine (10 mg/kg, p.o.) Animals were perorally (p.o.) pre-treated with CPAE during 15 days and intoxicated with a single oral administration of EtOH (4 g/kg b.w.) for two hours. RESULTS: The colorimetric analysis demonstrated that the CPAE exhibited an importance in vitro antioxidant activity against ABTS and DPPH radicals. We found that CPAE pretreatment in vivo, protected against EtOH-induced macroscopic and histological changes induced in stomach mucosa. Carob extract administration also protected against alcohol-induced volume gastric juice decrease. More importantly, We showed that CPAE counteracted EtOH-induced gastric lipoperoxidation, reversed the decrease of sulfhydryl groups (-SH) an hydrogen peroxide (H2O2) levels, and prevented the depletion of antioxidant enzyme activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). CONCLUSIONS: These findings suggest that CPAE exerted a potential gastro-protective effect against EtOH-induced oxidative stress in rats, due in part, to its antioxidants properties.

Inhibitory Effects of Two Varieties of Tunisian Pomegranate (Punica granatum L.) Extracts on Gastrointestinal Transit in Rat.

The present study was undertaken to determine whether total and methanol juice extracts of two Tunisian Pomegranate (Punica granatum L.) varieties (Garsi and Gabsi) protect against diarrhea as well as their effects on gastrointestinal transit (GIT) in healthy rats. In this respect, male Wistar rats were used and divided into control- and pomegranate-treated groups. The antidiarrheal activity was evaluated using the castor oil-induced diarrhea method and the GIT was assessed using charcoal meal. Our results showed that total and methanol P. granatum juice extracts produced a significant dose-dependent protection against castor oil-induced diarrhea. Pomegranate extracts and juice also decreased the GIT significantly and dose dependently. Importantly, the Garsi variety appeared to be more effective than the Gabsi variety on these two parameters. These findings suggest that pomegranate extracts have a potent antidiarrheal property in rats confirming their efficiency in the Tunisian traditional medicine.

Chemical composition, antioxidant properties and hepatoprotective effects of chamomile (Matricaria recutita L.) decoction extract against alcohol-induced oxidative stress in rat.

The present study assessed the chemical composition, antioxidant properties, and hepatoprotective effects of subacute pre-treatment with chamomile (Matricaria recutita L.) decoction extract (CDE) against ethanol (EtOH)-induced oxidative stress in rats. The colorimetric analysis demonstrated that the CDE is rich in total polyphenols, total flavonoids and condensed tannins, and exhibited an important in vitro antioxidant activity. The use of LC/MS technique allowed us to identify 10 phenolic compounds in CDE. We found that CDE pretreatment, in vivo, protected against EtOH-induced liver injury evident by plasma transaminases activity and preservation of the hepatic tissue structure. The CDE counteracted EtOH-induced liver lipoperoxidation, preserved thiol -SH groups and prevented the depletion of antioxidant enzyme activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). We also showed that acute alcohol administration increased tissue and plasma hydrogen peroxide (H(2)O(2)), calcium and free iron levels. More importantly, CDE pre-treatment reversed all EtOH-induced disturbances in intracellular mediators. In conclusion, our data suggest that CDE exerted a potential hepatoprotective effect against EtOH-induced oxidative stress in rat, at least in part, by negatively regulating Fenton reaction components such as H(2)O(2) and free iron, which are known to lead to cytotoxicity mediated by intracellular calcium deregulation.

Effects of dates pulp extract and palm sap (Phoenix dactylifera L.) on gastrointestinal transit activity in healthy rats.

The current study was performed to measure the chemical composition and the effects of dates pulp extract and palm sap on gastrointestinal transit (GIT) activity in healthy adult rats. In this respect, male Wistar rats fasted for 24 hours were used and received per orally (p.o.) sodium chloride (NaCl) (0,9%) (control group) or various doses of dates pulp extract (150 and 300 mg/kg, body weight [b.w.]) and palm sap (0.4 and 4 mL/kg, b.w.). Two other groups of rats (batch tests) received, respectively, clonidine (an alpha-2 adrenergic agonist, 1 mg/kg, b.w.) and yohimbine (an alpha-2 adrenergic antagonist, 2mg/kg, b.w.). Chemical analysis showed that the dates pulp extract is more rich in sugars and minerals, especially potassium and sucrose, as compared with palm sap composition. On the other hand, in vivo study showed that the aqueous dates pulp extract significantly, and dose dependently, increased the GIT activity while the palm sap slightly increased it. Moreover, a converse effect has been observed using clonidine (decreased 68%) and yohimbine (increased 33%) on the GIT activity. These findings suggest that dates pulp extract and palm sap have a stimulating effect on GIT activity in rats and confirm their use in traditional Tunisian medicine for the treatment of constipation.

Antidiarrheal and antioxidant activities of chamomile (Matricaria recutita L.) decoction extract in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Matricaria recutita L. (Chamomile) has been widely used in the Tunisian traditional medicine for the treatment of digestive system disorders. The present work aims to investigate the protective effects of chamomile decoction extract (CDE) against castor oil-induced diarrhea and oxidative stress in rats. METHODS: The antidiarrheal activity was evaluated using castor oil-induced diarrhea method. In this respect, rats were divided into six groups: Control, Castor oil, Castor oil+Loperamide (LOP) and Castor oil+various doses of CDE. Animals were per orally (p.o.) pre-treated with CDE during 1h and intoxicated for 2 or 4h by acute oral administration of castor oil. RESULTS: Our results showed that CDE produced a significant dose-dependent protection against castor oil-induced diarrhea and intestinal fluid accumulation. On the other hand, we showed that diarrhea was accompagned by an oxidative stress status assessed by an increase of malondialdehyde (MDA) level and depletion of antioxidant enzyme activities as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Castor oil also increased gastric and intestinal mucosa hydrogen peroxide (H2O2) and free iron levels. Importantly, we showed that chamomile pre-treatment abrogated all these biochemical alterations. CONCLUSION: These findings suggested that chamomile extract had a potent antidiarrheal and antioxidant properties in rats confirming their use in traditional medicine.

Efficacy and toxicity of intravenous iron in a mouse model of critical care anemia*.

OBJECTIVE: Anemia is common in critically ill patients, due to inflammation and blood loss. Anemia can be associated with iron deficiency and low serum hepcidin levels. However, iron administration in this setting remains controversial because of its potential toxicity, including oxidative stress induction and sepsis facilitation. The objective of this work was to determine the efficacy and toxicity of iron administration using a mouse model mimicking critical care anemia as well as a model of acute septicemia. DESIGN: Prospective, randomized, open label controlled animal study. SETTING: University-based research laboratory. SUBJECTS: C57BL/6 and OF1 mice. INTERVENTIONS: Intraperitoneal injection of zymosan inducing generalized inflammation in C57BL/6 mice, followed in our full model by repeated phlebotomies. A dose equivalent to 15 mg/kg of ferric carboxymaltose was injected intravenously on day 5. To assess the toxicity of iron in a septicemia model, OF1 mice were simultaneously injected with iron and different Escherichia coli strains. MEASUREMENTS AND MAIN RESULTS: To investigate the effect of iron on oxidative stress, we measured reactive oxygen species production in the blood using luminol-amplified chemiluminescence and superoxide dismutase 2 messenger RNA levels in the liver. These markers of oxidative stress were increased after iron administration in control mice but not in zymosan-treated mice. Liver catalase messenger RNA levels decreased in iron-treated control mice. Iron administration was not associated with increased mortality in the septicemia model or in the generalized inflammation model. Iron increased hemoglobin levels in mice fed with a low iron diet and subjected to phlebotomies and zymosan 2 wks after treatment administration. CONCLUSIONS: Adverse effects of intravenous iron supplementation by ferric carboxymaltose seem to be minimal in our animal models. Furthermore, iron appears to be effective in correcting anemia, despite inflammation. Studies of efficacy and safety of iron in critically ill patients are warranted.

An aqueous pomegranate peel extract inhibits neutrophil myeloperoxidase in vitro and attenuates lung inflammation in mice.

Punica granatum peel aqueous extract (PGE) is widely used to treat disorders such as inflammation, ulcers and infections, but its pharmacological target is not known. In this study we investigated the effect of PGE on human neutrophil reactive oxygen species (ROS) production in vitro and on LPS-induced lung inflammation in vivo in mice. Neutrophils were isolated and ROS generation was measured by luminol-amplified chemiluminescence. Superoxide anion generation was detected by the cytochrome c reduction assay. H(2)O(2) was detected by DCFH fluorescence assay. Myeloperoxidase (MPO) activity was measured by the tetramethyl benzidine oxidation method. Lung inflammation was induced in mice by LPS instillation. PGE inhibited luminol-amplified chemiluminescence of resting neutrophils and N-formyl-methionyl-leucyl-phenylalanine (fMLF)- or phorbol myristate acetate (PMA)-stimulated neutrophils, in a concentration-dependent manner. PGE had no effect on superoxide anion generation, suggesting that it does not directly inhibit NADPH oxidase activity or activation pathways, or scavenge superoxide anions. PGE did not scavenge H(2)O(2) but directly inhibited myeloperoxidase activity in vitro. In vivo studies showed that PGE also attenuated LPS-induced lung inflammation in mice. So this study reveals that PGE inhibits neutrophil MPO activity and attenuates LPS-induced lung inflammation in mice. Inhibition of MPO activity by PGE could explain its anti-inflammatory action.

High hepatic glutathione stores alleviate Fas-induced apoptosis in mice.

BACKGROUND/AIMS: The agonistic Jo2 anti-Fas antibody reproduces human fulminant hepatitis in mice. We tested the hypothesis that enhancing hepatic glutathione (GSH) stores may prevent Jo2-induced apoptosis. METHODS: We fed mice with a normal diet or a sulfur amino acid-enriched (SAA(+)) diet increasing hepatic GSH by 63%, and challenged these mice with Jo2. RESULTS: The SAA(+) diet markedly attenuated the Jo2-mediated decrease in hepatic GSH and the increase in the oxidized glutathione (GSSG)/GSH ratio in cytosol and mitochondria. The SAA(+) diet prevented protein kinase Czeta (PKCzeta) and p47(phox) phosphorylations, Yes activation, Fas-tyrosine phosphorylation, Bid truncation, Bax, and cytochrome c translocations, the mitochondrial membrane potential collapse, caspase activation, DNA fragmentation, hepatocyte apoptosis, and mouse lethality after Jo2 administration. The protective effect of the SAA(+) diet was abolished by a small dose of phorone decreasing hepatic GSH back to the levels observed in mice fed the normal diet. Conversely, administration of GSH monoethyl ester after Jo2 administration prevented hepatic GSH depletion and attenuated toxicity in mice fed with the normal diet. CONCLUSIONS: The SAA(+) diet preserves GSSG/GSH ratios, and prevents PKCzeta and p47(phox) phosphorylations, Yes activation, Fas-tyrosine phosphorylation, mitochondrial permeabilization, and hepatic apoptosis after Fas stimulation. GSH monoethyl ester is also protective, suggesting possible clinical applications.

Antioxidant effect of hydroxytyrosol, a polyphenol from olive oil: scavenging of hydrogen peroxide but not superoxide anion produced by human neutrophils.

Hydroxytyrosol (HT) (also known as dihydroxyphenylethanol (DPE)) is a polyphenol extracted from virgin olive oil. HT is known to exert an antioxidant effect but the mechanism of action and the identity of the reactive oxygen molecule(s) targeted are not known. In this study, we show that HT inhibits luminol-amplified chemiluminescence of human neutrophils stimulated with N-formyl-methionyl-leucyl-phenylalanine (fMLP), phorbol myristate acetate (PMA) and opsonized zymosan. This effect was dose-dependent and occurred immediately after the addition of HT. However, HT had no effect on lucigenin-amplified chemiluminescence, suggesting that it does not inhibit NADPH oxidase activation or scavenge superoxide anions. Furthermore, HT inhibited H(2)O(2)-dependent-dichlorofuoroscein (DCFH) fluorescence of activated neutrophils, as measured by flow cytometry. Finally, HT inhibited luminol-amplified chemiluminescence in a cell-free system consisting of H(2)O(2) and HRPO. These results suggest that HT, a polyphenol derived from olive oil, could exert its antioxidant effect by scavenging hydrogen peroxide but not superoxide anion released during the respiratory burst.