Sensitization of GSH synthesis by curcumin curtails acrolein-induced alveolar epithelial apoptosis via Keap1 cysteine conjugation: A randomized controlled trial and experimental animal model of pneumonitis.

INTRODUCTION: Epidemiological studies have reported an association between exposures to ambient air pollution and respiratory diseases, including chronic obstructive pulmonary disease (COPD). Pneumonitis is a critical driving factor of COPD and exposure to air pollutants (e.g., acrolein) is associated with increased incidence of pneumonitis. OBJECTIVES: Currently available anti-inflammatory therapies provide little benefit against respiratory diseases. To this end, we investigated the preventive role of curcumin against air pollutant-associated pneumonitis and its underlying mechanism. METHODS: A total of 40 subjects was recruited from Chengdu, China which is among the top three cities in terms of respiratory mortality related to air pollution. The participants were randomly provided either placebo or curcumin supplements for 2 weeks and blood samples were collected at the baseline and at the end of the intervention to monitor systemic markers. In our follow up mechanistic study, C57BL/6 mice (n = 40) were randomly allocated into 4 groups: Control group (saline + no acrolein), Curcumin only group (curcumin + no acrolein), Acrolein only group (saline + acrolein), and Acrolein + Curcumin group (curcumin + acrolein). Curcumin was orally administered at 100 mg/kg body weight once a day for 10 days, and then the mice were subjected to nasal instillation of acrolein (5 mg/kg body weight). Twelve hours after single acrolein exposure, all mice were euthanized. RESULTS: Curcumin supplementation, with no noticeable adverse responses, reduced circulating pro-inflammatory cytokines in association with clinical pneumonitis as positive predictive while improving those of anti-inflammatory cytokines. In the pre-clinical study, curcumin reduced pneumonitis manifestations by suppression of intrinsic and extrinsic apoptotic signaling, which is attributed to enhanced redox sensing of Nrf2 and thus sensitized synthesis and restoration of GSH, at least in part, through curcumin-Keap1 conjugation. CONCLUSIONS: Our study collectively suggests that curcumin could provide an effective preventive measure against air pollutant-enhanced pneumonitis and thus COPD.

Long-term cysteine fortification impacts cysteine/glutathione homeostasis and food intake in ageing rats.

PURPOSE: Healthy ageing is associated with higher levels of glutathione. The study aimed to determine whether long-term dietary fortification with cysteine increases cysteine and glutathione pools, thus alleviating age-associated low-grade inflammation and resulting in global physiological benefits. METHODS: The effect of a 14-week dietary fortification with cysteine was studied in non-inflamed (NI, healthy at baseline) and in spontaneously age-related low-grade inflamed (LGI, prefrail at baseline) 21-month-old rats. Fifty-seven NI rats and 14 LGI rats received cysteine-supplemented diet (4.0 g/kg of free cysteine added to the standard diet containing 2.8 g/kg cysteine). Fifty-six NI rats and 16 LGI rats received a control alanine-supplemented diet. RESULTS: Cysteine fortification in NI rats increased free cysteine (P < 0.0001) and glutathione (P < 0.03) in the liver and the small intestine. In LGI rats, cysteine fortification increased total non-protein cysteine (P < 0.0007) and free cysteine (P < 0.03) in plasma, and free cysteine (P < 0.02) and glutathione (P < 0.01) in liver. Food intake decreased over time in alanine-fed rats (r² = 0.73, P = 0.0002), whereas it was constant in cysteine-fed rats (r² = 0.02, P = 0.68). Cysteine fortification did not affect inflammatory markers, mortality, body weight loss, or tissue masses. CONCLUSION: Doubling the dietary intake of cysteine in old rats increased cysteine and glutathione pools in selected tissues. Additionally, it alleviated the age-related decline in food intake. Further validation of these effects in the elderly population suffering from age-related anorexia would suggest a useful therapeutic approach to the problem.

Aged garlic extract reduces blood pressure in hypertensives: a dose-response trial.

BACKGROUND/OBJECTIVES: Hypertension affects about 30% of adults worldwide. Garlic has blood pressure-lowering properties and the mechanism of action is biologically plausible. Our trial assessed the effect, dose-response, tolerability and acceptability of different doses of aged garlic extract as an adjunct treatment to existing antihypertensive medication in patients with uncontrolled hypertension. SUBJECTS/METHODS: A total of 79 general practice patients with uncontrolled systolic hypertension participated in a double-blind randomised placebo-controlled dose-response trial of 12 weeks. Participants were allocated to one of three garlic groups with either of one, two or four capsules daily of aged garlic extract (240/480/960 mg containing 0.6/1.2/2.4 mg of S-allylcysteine) or placebo. Blood pressure was assessed at 4, 8 and 12 weeks and compared with baseline using a mixed-model approach. Tolerability was monitored throughout the trial and acceptability was assessed at 12 weeks by questionnaire. RESULTS: Mean systolic blood pressure was significantly reduced by 11.8±5.4 mm Hg in the garlic-2-capsule group over 12 weeks compared with placebo (P=0.006), and reached borderline significant reduction in the garlic-4-capsule group at 8 weeks (-7.4±4.1 mm Hg, P=0.07). Changes in systolic blood pressure in the garlic-1-capsule group and diastolic blood pressure were not significantly different to placebo. Tolerability, compliance and acceptability were high in all garlic groups (93%) and highest in the groups taking one or two capsules daily. CONCLUSIONS: Our trial suggests aged garlic extract to be an effective and tolerable treatment in uncontrolled hypertension, and may be considered as a safe adjunct treatment to conventional antihypertensive therapy.

Healthy and adverse effects of plant-derived functional metabolites: the need of revealing their content and bioactivity in a complex food matrix.

In recent years, both food quality and its effect on human health have become a fundamental issue all over the world. As a consequence of this new and increased awareness, American, European, and Asian policymakers have strongly encouraged the research programs on food quality and safety thematic. Attempts to improve human health and to satisfy people's desire for healthcare without intake of pharmaceuticals, has led the food industry to focus attention on functional or nutraceutical food. For a long time, compounds with nutraceutical activity have been produced chemically, but the new demands for a sustainable life have gradually led the food industry to move towards natural compounds, mainly those derived from plants. Many phytochemicals are known to promote good health, but, sometimes, undesirable effects are also reported. Furthermore, several products present on the market show few benefits and sometimes even the reverse - unhealthy effects; the evidence of efficacy is often unconvincing and epidemiological studies are necessary to prove the truth of their claims. Therefore, there is a need for reliable analytical control systems to measure the bioactivity, content, and quality of these additives in the complex food matrix. This review describes the most widespread nutraceutics and an analytical control of the same using recently developed biosensors which are promising candidates for routine control of functional foods.

A maxed-out liver: a case of acute-on-chronic liver failure.

A 51-year-old man from Puerto Rico with Child-Turcotte-Pugh Class C decompensated cirrhosis due to genotype 1a chronic hepatitis C was referred for worsening jaundice and diuretic-resistant ascites. He began experiencing symptoms of hepatic decompensation 5 months prior to referral with new-onset ascites and spontaneous bacterial peritonitis, evolving into diuretic-resistant ascites, increasing jaundice, and a MELD increase from 12 to 29. During his hospitalization, his MELD score increased to >40 from a rapidly increasing international normalized ratio (INR) and evolving type 1 hepatorenal syndrome. Clinically, the patient appeared quite well despite such a high MELD score. After an extensive pretransplant evaluation and exclusion of infection, he underwent successful orthotopic liver transplantation. After histologic examination of the explanted liver, he subsequently admitted to 5 months of daily use of a detoxifying supplement known as MaxOne (®), containing D-ribose- L-cysteine, consistent with a drug-induced acute-on-chronic liver failure. The use of complementary and alternative medicines and its potential for causing drug-induced liver injury and acute-on chronic liver failure requires a high index of suspicion and increased awareness among health care providers.

Excess dietary L-cysteine causes lethal metabolic acidosis in chicks.

A 72-h time-course study was conducted to elucidate the physiological mechanism underlying cysteine (Cys) toxicity in chicks beginning at 8-d posthatch. Biochemical markers quantified in plasma and liver samples collected from chicks receiving 30 g/kg excess dietary Cys were compared with baseline measurements from chicks receiving an unsupplemented corn-soybean meal diet over a 72-h feeding period. Concomitant with chick mortality were indices of acute metabolic acidosis, including a rapid increase (P < 0.001) in anion gap that resulted from a reduction (P < 0.001) in plasma HCO(3)(-) of approximately 40% and a 2.8-fold increase (P < 0.001) in plasma sulfate in chicks receiving excess Cys. Additionally, provision of 30 g/kg excess Cys resulted in a 1.5-fold increase (P < 0.05) in hepatic oxidized glutathione compared with the 0-h control time-point. Excess dietary Cys did not affect plasma free Met, but plasma free Cys increased (P < 0.05) from 89 to 107 mumol/L at 12 h and remained elevated through 36 h. Strikingly, ingestion of 30 g/kg excess Cys caused more than a doubling (P < 0.001) of plasma free cystine, the oxidized form of Cys, beginning 12 h after initiating the study, and it remained elevated throughout the 72-h feeding period. Taken together, these data suggest that ingestion of 30 g/kg excess l-Cys causes both acute metabolic acidosis and oxidative stress in young chicks when fed a nutritionally adequate, corn-soybean meal diet.

A case with life-threatening interstitial pneumonia associated with bucillamine treatment.

We report a case of bucillamine-induced interstitial pneumonia accompanied by severe hypoxemia in an 83-year-old woman who had rheumatoid arthritis. Respiratory failure worsened even after withdrawal of bucillamine and administration of high-dose corticosteroids, and mechanical ventilation was required. A review of 15 cases with bucillamine-induced pulmonary injury suggests that advanced age may be associated with the development of severe interstitial pneumonia. Bucillamine can cause corticosteroid-resistant and life-threatening lung injury, especially in the elderly.

Evidence of a novel docetaxel sensitizer, garlic-derived S-allylmercaptocysteine, as a treatment option for hormone refractory prostate cancer.

The recent introduction of docetaxel in the treatment of hormone refractory prostate cancer (HRPC) has made a small but significant impact on patient survival. However, its effect is limited by intolerance and resistance. The aim of our study was to investigate if the garlic-derived compound, S-allylmercaptocysteine (SAMC), was able to act as a docetaxel sensitizing agent. First, the effect of SAMC on docetaxel sensitivity was examined on 3 HRPC cell lines by colony forming assay. We found that SAMC increased the efficacy of docetaxel on colony forming inhibition by 9-50% compared to single agent treatment. Second, using the HRPC CWR22R nude mice model, we found that the combination of SAMC and docetaxel was 53% more potent than docetaxel alone (p = 0.037). In addition, there was no additive toxicity in the mice treated with the combination therapy evidenced by histological and functional analysis of liver, kidney and bone marrow. These results suggest that SAMC is able to increase the anticancer effect of docetaxel without causing additional toxic effect in vivo. Third, flow cytometry and Western blotting analysis on HRPC cell lines demonstrated that SAMC promoted docetaxel-induced G2/M phase cell cycle arrest and apoptotic induction. In addition, immunohistochemistry on CWR22R xenograft revealed a suppression of Bcl-2 expression and upregulation of E-cadherin in the SAMC and docetaxel treated animals. These results suggest that SAMC may promote docetaxel-induced cell death through promoting G2/M cell cycle arrest and apoptosis. Our study implies a potential role for SAMC in improving docetaxel based chemotherapy for the treatment of HRPC.

Proteomics of S-(1, 2-dichlorovinyl)-L-cysteine-induced acute renal failure and autoprotection in mice.

Previous studies (Vaidya VS, Shankar K, Lock EA, Bucci TJ, Mehendale HM. Toxicol Sci 74: 215-227, 2003; Korrapati MC, Lock EA, Mehendale HM. Am J Physiol Renal Physiol 289: F175-F185, 2005; Korrapati MC, Chilakapati J, Lock EA, Latendresse JR, Warbritton A, Mehendale HM. Am J Physiol Renal Physiol 291: F439-F455, 2006) demonstrated that renal repair stimulated by a low dose of S-(1,2-dichlorovinyl)l-cysteine (DCVC; 15 mg/kg i.p.) 72 h before administration of a normally lethal dose (75 mg/kg i.p.) protects mice from acute renal failure (ARF) and death (autoprotection). The present study identified the proteins indicative of DCVC-induced ARF and autoprotection in male Swiss Webster mice. Renal dysfunction and injury were assessed by plasma creatinine and histopathology, respectively. Whole-kidney homogenates were run on two-dimensional gel electrophoresis gels, and the expression of 18 common proteins was maximally changed (> or =10-fold) in all the treatment groups and they were conclusively identified by liquid chromatography tandem mass spectrometry. These proteins were mildly downregulated after low dose alone and in autoprotected mice in contrast to severe downregulation with high dose alone. Glucose-regulated protein 75 and proteasome alpha-subunit type 1 were further investigated by immunohistochemistry for their localization in the kidneys of all the groups. These proteins were substantially higher in the proximal convoluted tubular epithelial cells in the low-dose and autoprotected groups compared with high-dose alone group. Proteins involved in energetics were downregulated in all the three groups of mice, leading to a compromise in cellular energy. However, energy is recovered completely in low-dose and autoprotected mice. This study provides the first report on proteomics of DCVC-induced ARF and autoprotection in mice and reflects the application of proteomics in mechanistic studies as well as biomarker development in a variety of toxicological paradigms.

Augmentation of CD8 and CD4 lymphocytes subsets in AIDS infected children after treatment with a non-toxic chelating agents compound--Rodilemid.

Twelve children were included into the protocol, 5 in March 1989 and 7 in April 1993. All of them were HIV 1 positive and had diarrhoea, important adenopathy and opportunistic infections. Seven out of 12 patients had an immunological monitoring. One out of 12 children with B hepatitis died with liver cirrhosis. Eleven children had a clear improvement in their clinical course, during the treatment. Five out of 7 patients had a significant increase of the CD4 lymphocytes at 4 and 7 months follow-up. Four patients had an important and significant increase of the CD8 count at 4 months and 6 out of 7 patients at 7 months. Interestingly, in 4 out of 7 patients after 7 months treatment we observed higher than normal value of the CD8 count. Variations observed for CD8 population compared to CD4 were more important.

Ultrastructural alterations in testes from rats treated with cysteine.

Cysteine administration in relatively large doses has been repetitively employed as preventive agent against chemically induced cell injury or as radioprotector. In this work we report that administration of a dose standard for those purposes (1.9 gr/kg, po in water) causes significant ultrastructurally evident alterations in testes at 24h. Damage involves Sertoli cells and spermatids. Alterations found in the former include dilatation of nuclear membrane and of the smooth (SER) and rough endoplasmic reticulum (RER) and detachment of ribosomes from RER. Cytoplasm appeared more sparse and electron lucent than in controls and contained more lipid droplets and lysosomes. Mitochondria exhibited alterations in shape and size. Damage in spermatids consisted of the appearance of irregular shape of the nucleus and alterations in their acrosomal caps. There was no histochemical evidence for either calcium accumulation or lipid peroxidation occurrence in testes of cysteine-treated animals. Results indicate that the large doses of cysteine employed in prevention of radiation or chemical effects is able to cause injury to Sertoli cells of the testes. Damage observed does not reach irreversible stages but may be sufficient to lead to production of abnormal spermatids.

Responses to oral methionine supplementation in sheep fed on kale (Brassica oleracea) diets containing S-methyl-L-cysteine sulphoxide.

1. Responses to twice-weekly oral supplementation with 4.0 g methionine were measured with lambs (27 kg) grazing kale (Brassica oleracea) for 10 weeks (Expt 1). In a second experiment with sheep fed on kale at hourly intervals, rumen fractional outflow rates of CrEDTA and ruthenium Tris(1,10 phenanthroline) markers were measured from the rates of decline in their concentrations. Rumen turnover of S-methyl-L-cysteine sulphoxide (SMCO) and of carbohydrate (CHO) constituents were also measured. The kale fed contained 11.4 g SMCO/kg dry matter and the ratio, readily-fermentable: structural CHO was high at 2.9. 2. Severe haemolytic anaemia, associated with low live-weight gain (LWG), occurred in the lambs during the initial 5 weeks of grazing, due to rumen fermentation of SMCO. Oral methionine supplementation raised plasma concentrations of methionine and cysteine, increased wool growth rate, and increased LWG during the initial 5 weeks. Methionine supplementation also increased rumen pool and plasma SMCO concentrations, suggesting reduced rumen SMCO fermentation. 3. In Expt 2, rumen degradation rate of SMCO (1.2/h) was calculated to be twice as fast as that of the most rapidly fermented dietary CHO constituents and eight times faster than the rate of water outflow (0.16/h), thus explaining its virtually complete rumen degradation and toxicity in brassica diets. It was estimated that 1.2 g of each 4.0 g methionine administered would have escaped rumen degradation, due to the high rate of water outflow from the rumen. 4. Disappearance rates of CHO constituents from the rumen were as predicted for normal ruminant diets, showing that rumen metabolism of SMCO did not have a depressive effect.(ABSTRACT TRUNCATED AT 250 WORDS)

Growth depression and tissue reaction to the consumption of excess dietary methionine and S-methyl-L-cysteine.

Similar depressions in growth were observed when rats consumed a 10% casein basal diet containing equal quantities of either methionine or S-methyl-L-cysteine. Supplemental glycine or serine partially alleviated the growth depression caused by the high levels of methionine but were ineffective in alleviating the growth depression caused by high levels of S-methylcysteine. Histological examination of five organs of rats fed the basal, high methionine or high S-methylcysteine diet for 6, 13 or 20 days revealed that only the spleens were affected in that there was erythrocyte engorgement and an accumulation of hemosiderin. The intensity of iron staining in spleens decreased from the second to the third week. The similarity in the depression of growth and splenic damage observed in rats consuming high levels of methionine or S-methylcysteine is consistent with an earlier suggestion that metabolism of the methionine or S-methylcysteine is consistent with an earlier suggestion that metabolism of the methyl group is in some way involved in the toxicity of methionine.

Collagenase inhibitors: rationale for their use in treating corneal ulceration.

Tissue collagenases have been implicated in corneal ulceration in human corneal disease and in ulceration of the rabbit cornea that has served as a model system. Such enzymes from the rabbit and human cornea are inhibited by metal-binding agents of the EDTA type, by thiols, and by the human serum antiprotease alpha2-macroglobulin. Determination of the relative efficacies of collagenase inhibitors indicates that EDTA and Ca-EDTA are about one hundred times more effective on a molar basis than L-cysteine and its derivatives, N-acetyl-L-cysteine and D-penicillamine. The alpha2-macroglobulin on a molar basis, is superior as an inhibitor to the metal-binding agents and thiols. Although Ca may be a necessary cofactor of the corneal collagenases, such a requirement has not been established unequivocally. Inhibition and isotope studies do indicate a requirement for Zn. Thiols are thought to inhibit corneal collagenases by binding to or removing an intrinsic metal cofactor (Zn), and/or possibly by reducing one or more disulfide bonds. Inhibition by both EDTA-type agents and thiols is largely reversible by dialysis. The human alpha2-macroglobulin appears to inhibit corneal colleagenases irreversibly by forming tight complexes with them. Ca-EDTA, cysteine, and acetylcysteine, given as eyedrops, are able to prevent or retard ulceration in the alkali-burned rabbit cornea. They appear to have some efficacy in the prevention of corneal ulceration in humans. EDTA-type compounds are quite stable under routine storage, while acetylcysteine is more stable than cysteine. EDTA is quite toxic and should not be used as eye medication. Ca-EDTA has a low toxicity, and cysteine and acetylcysteine have even lower toxicity. It is not yet certain which inhibitor has the most favorable therapeutic index for clinical use, or is the optimal mode of drug delivery known. However, the collagenase inhibitors seem to have therapeutic promise in the prevention of corneal ulceration.