Effect of alpha-tocopherol on the expression of hepatic vascular stress genes in response to sepsis

The Interplay of Oxidative Stress and ROS Scavenging: Antioxidants as a Therapeutic Potential in Sepsis

Oxidative stress resulting from the disproportion of oxidants and antioxidants contributes to both physiological and pathological conditions in sepsis. To combat this, the antioxidant defense system comes into the picture, which contributes to limiting the amount of reactive oxygen species (ROS) leading to the reduction of oxidative stress. However, a strong relationship has been found between scavengers of ROS and antioxidants in preclinical in vitro and in vivo models. ROS is widely believed to cause human pathology most specifically in sepsis, where a small increase in ROS levels activates signaling pathways to initiate biological processes. An inclusive understanding of the effects of ROS scavenging in cellular antioxidant signaling is essentially lacking in sepsis. This review compiles the mechanisms of ROS scavenging as well as oxidative damage in sepsis, as well as antioxidants as a potent therapeutic. Direct interaction between ROS and cellular pathways greatly affects sepsis, but such interaction does not provide the explanation behind diverse biological outcomes. Animal models of sepsis and a number of clinical trials with septic patients exploring the efficiency of antioxidants in sepsis are reviewed. In line with this, both enzymatic and non-enzymatic antioxidants were effective, and results from recent studies are promising. The usage of these potent antioxidants in sepsis patients would greatly impact the field of medicine.

Eupatilin: a natural pharmacologically active flavone compound with its wide range applications

Eupatilin (5,7-dihydroxy-3',4',6-trimethoxyflavone) is a pharmacologically active flavone which has been isolated from a variety of medicinal plants. Eupatilin is known to possess various pharmacological properties such as anti-cancer, anti-oxidant, and anti-inflammatory. It is speculated that eupatilin could be subjected to structural optimization for the synthesis of derivative analogs to reinforce its efficacy, to minimize toxicity, and to optimize absorption profiles, which will ultimately lead towards potent drug candidates. Although, reported data acclaim multiple pharmacological activities of eupatilin but further experimentations on its molecular mechanism of action are yet mandatory to elucidate full spectrum of its pharmacological activities.

Topical Application of Eupatilin Ameliorates Atopic Dermatitis-Like Skin Lesions in NC/Nga Mice

Background

Atopic dermatitis (AD) is an inflammatory skin disorder with severe pruritus. Despite advancements in medicine, therapeutic treatments for AD are still limited. Eupatilin (5,7-dihydroxy-30,40,6-trimethoxyflavone) is one of the lipophilic flavonoids from Artemisia umbelliformis Lam. and Artemisia genipi Weber.

Objective

Although it has been reported to act a role in improving inflammation, its action on AD is uncertain. In this study, we examined the role of eupatilin on AD-like skin lesions in NC/Nga mice.

Methods

2,4-dinitrochlorobenzene was repeatedly applied to the ear of NC/Nga mice to produce AD-like skin lesions. Eupatilin (1%, once a day for 5 consecutive days/week) was applied topically for four weeks for the evaluation of its therapeutic effects.

Results

1% eupatilin cream significantly reduced the clinical severity score of AD-like lesions, compared to the vehicle (p<0.005). A histopathological analysis revealed that 1% eupatilin cream significantly decreased the mast cell infiltration as well as inflammatory cell infiltration, compared to the vehicle (p<0.005). We showed that 1% eupatilin cream significantly reduced the expression of thymic stromal lymphopoietin, tumor necrosis factor-α, interleukin-4, and interleukin-19, but not interferon-γ, compared to the vehicle (p<0.005).

Conclusion

Considering the therapeutic reaction of eupatilin on AD-like lesions as in this study, the substance has a promising to be an adjuvant topical agent for the control of AD.

Potential application of benzo(a)pyrene-associated adducts (globin or lipid) as blood biomarkers for target organ exposure and human risk assessment

In order to investigate the potential application of blood biomarkers as surrogate indicators of carcinogen-adduct formation in target-specific tissues, temporal formation of benzo[a]pyrene (BaP)-associated DNA adducts, protein adducts, or lipid damage in target tissues such as lung, liver, and kidney was compared with globin adduct formation or plasma lipid damage in blood after continuous intraperitoneal (ip) injection of [(3)H]BaP into female ICR mice for 7 d. Following treatment with [(3)H]BaP, formation of [(3)H]BaP-DNA or -protein adducts in lung, liver, and kidney increased linearly, and persisted thereafter. This finding was similar to the observed effects on globin adduct formation and plasma lipid damage in blood. The lungs contained a higher level of DNA adducts than liver or kidneys during the treatment period. Further, the rate of cumulative adduct formation in lung was markedly greater than that in liver. Treatment with a single dose of [(3)H]BaP indicated that BaP-globin adduct formation and BaP-lipid damage in blood reached a peak 48 h after treatment. Overall, globin adduct formation and lipid damage in blood were significantly correlated with DNA adduct formation in the target tissues. These data suggest that peripheral blood biomarkers, such as BaP-globin adduct formation or BaP-lipid damage, may be useful for prediction of target tissue-specific DNA adduct formation, and for risk assessment after exposure.

FOXL2 molecular testing in ovarian neoplasms: diagnostic approach and procedural guidelines

A single, recurrent somatic point mutation (402C→G) in FOXL2 has been described in almost all adult-type granulosa cell tumors but not other ovarian neoplasms. Histopathological features of adult-type granulosa cell tumors can be mimicked by a variety of other tumors, making diagnosis of adult-type granulosa cell tumor challenging. It has been suggested that molecular testing for FOXL2 mutation might be a useful tool in the diagnosis of adult-type granulosa cell tumors. The aim of this study was to demonstrate how testing for the FOXL2 mutation can be used in a gynecological pathology consultation service and to establish clear procedural guidelines for FOXL2 testing. Immunohistochemistry for FOXL2 was done using an anti-FOXL2 polyclonal antiserum. If immunohistochemistry was positive, FOXL2 mutation status was subsequently analyzed using a TaqMan assay. A dilution experiment was done to assess the sensitivity and minimum tumor cellularity requirements for our TaqMan assay. Twenty problematic cases were assessed, where the differential diagnosis after the initial investigations included adult-type granulosa cell tumors. Differential diagnoses included: thecoma, Sertoli-Leydig cell tumor, juvenile granulosa cell tumor, endometrial stromal sarcoma and others. In all cases, FOXL2 immunohistochemistry was positive and in six samples the FOXL2 mutation was detected, thus confirming a diagnosis of adult-type granulosa cell tumor. The TaqMan assay was able to reliably detect the FOXL2 mutation with input DNA in the range of 2.5-20 ng, and with a minimum of 25% tumor cell nuclei. The analysis of the FOXL2 mutational status in clinical samples is a useful diagnostic tool in situations where the differential diagnosis is between adult-type granulosa cell tumor and other ovarian tumors. The TaqMan assay requires a minimum of 2.5 ng DNA, with optimal assay performance for 5 to 10 ng DNA input. Laser capture or needle-macrodissection should be undertaken to enrich samples with tumor cell content below 25%.

DNA extract characterization process for microbial detection methods development and validation

Background

Quantitative polymerase chain reaction (qPCR) assays used in pathogen detection require rigorous methods development including characterizing DNA extraction products. A DNA extract characterization process is demonstrated using DNA extracted from five different cells types (two Gram-negatives: Escherichia coli, and Burkholderia thailandensis, spores and vegetative cells from the Gram-positive Bacillus cereus, and yeast Saccharomyces cerevisiae) with six different methods.

Results

DNA extract quantity (concentration and extraction efficiency) and quality (purity and intactness) varied by cell type and extraction method enabling the demonstration of different DNA characterization methods. DNA purity was measured using UV spectroscopy, where the A₂₆₀/A₂₈₀ and A₂₆₀/A₂₃₀ ratios are indicators of different contaminants. Reproducibility of UV spectroscopy measurements decreased for DNA concentrations less than 17.5 ng/μL. Forty-seven extracts had concentrations greater than 17.5 ng/μL, 25 had A₂₆₀/A₂₈₀ above 2.0, and 28 had A₂₆₀/A₂₃₀ ratios below 1.8 indicating RNA and polysaccharide contamination respectively. Based on a qPCR inhibition assay the contaminants did not inhibit PCR. Extract intactness was evaluated using microfluidic gel electrophoresis. Thirty-five samples had concentrations above the limit of quantification (LOQ, roughly 11 ng/ μL), 93.5% of the DNA was larger than 1kb and 1% was smaller than 300 bp. Extract concentrations ranged from 1502.2 ng/μL to below the LOQ when UV spectroscopy, fluorometry, and qPCR were used. LOQ for UV spectroscopic and fluorometric measurements were 3.5 ng/μL and 0.25 ng/μL respectively. The qPCR LOQ varied by cell type (5.72 × 10^-3 ng/μL for E. coli, 2.66 × 10^-3 ng/μL, for B. cereus, 3.78 × 10^-3 ng/μL for B. thailandensis, and 7.67 × 10^-4 ng/μL for S. cerevisiae). A number of samples were below the UV spectroscopy (n = 27), flurometry (n = 15), and qPCR (n = 3) LOQ.

Conclusion

The presented DNA extract characterization process provides measures of DNA quantity and quality applicable to microbial detection methods development and validation studies. Evaluating DNA quality and quantity results in a better understanding of process LOD and contributing factors to suboptimal assay performance. The samples used demonstrated the use of different DNA characterization methods presented but did not encompass the full range of DNA extract characteristics.

The new vitamin E derivative, ETS-GS, protects against cecal ligation and puncture-induced systemic inflammation in rats

Sepsis-related systemic inflammation frequently occurs in the critical care setting. Systemic inflammation is implicated in the progression of organ injury, which is associated with a high mortality rate. Recently, vitamin E and glutamic acid have been reported to attenuate inflammation. We therefore investigated whether the vitamin E derivative, ETS-GS, could inhibit the secretion of cytokines and high-mobility group box 1 (HMGB1), and thereby reduce organ damage in a rat model of cecal ligation and puncture (CLP)-induced sepsis. Male Wistar rats weighing 250-300 g were used. Rats received water or ETS-GS (10 mg/kg) by oral administration for 3 weeks, and then sepsis was induced by CLP under sevoflurane anesthesia. Serum levels of interleukin-6, tumor necrosis factor-α, and HMGB1 were determined at 3, 6, and 12 h after CLP; lung histology was assessed at 12 h. Histology results showed markedly reduced interstitial edema and leukocytic infiltration in lung tissue harvested at 12 h in ETS-GS-treated mice compared with untreated controls. ETS-GS treatment also attenuated the CLP-induced increase in serum levels of cytokines and HMGB1. To investigate the mechanisms by which ETS-GS exerts its anti-inflammatory effects, the phosphorylation of Akt, IκBα, and mitogen-activated protein kinase (MAPK) was assessed in mouse macrophage RAW264.7 cells stimulated with LPS, with and without ETS-GS. In these in vitro studies, ETS-GS-induced phosphoinositide 3-kinase (PI3K)-Akt phosphorylation and inhibited IκBα and MAPK phosphorylation. ETS-GS blocked the CLP-induced septic shock response and protected against acute lung injury. This mechanism appeared to be mediated by the induction of PI3K-Akt and the inhibition of IκBα and MAPK phosphorylation. Given these results, ETS-GS shows promise as a potential therapeutic agent for sepsis.

Mice with heterozygous deficiency of lipoic acid synthase have an increased sensitivity to lipopolysaccharide-induced tissue injury

Alpha-lipoic acid (1, 2-dithiolane-3-pentanoic acid; LA), synthesized in mitochondria by LA synthase (Lias), is a potent antioxidant and a cofactor for metabolic enzyme complexes. In this study, we examined the effect of genetic reduction of LA synthesis on its antioxidant and anti-inflammatory properties using a model of LPS-induced inflammation in Lias+/- mice. The increase of plasma proinflammatory cytokine, TNF-alpha, and NF-kappaB at an early phase following LPS injection was greater in Lias+/- mice compared with Lias+/+ mice. The circulating blood white blood cell (WBC) and platelet counts dropped continuously during the initial 4 h. The counts subsequently recovered partially in Lias+/+ mice, but the recovery was impaired totally in Lias+/- mice. Administration of exogenous LA normalized the recovery of WBC counts in Lias+/- mice but not platelets. Enhanced neutrophil sequestration in the livers of Lias+/- mice was associated with increased hepatocyte injury and increased gene expression of growth-related oncogene, E-selectin, and VCAM-1 in the liver and/or lung. Lias gene expression in tissues was 50% of normal expression in Lias+/- mice and reduced further by LPS treatment. Decreased Lias expression was associated with diminished hepatic LA and tissue oxidative stress. Finally, Lias+/- mice displayed enhanced mortality when exposed to LPS-induced sepsis. These data demonstrate the importance of endogenously produced LA for preventing leukocyte accumulation and tissue injury that result from LPS-induced inflammation.

Antioxidant supplementation in sepsis and systemic inflammatory response syndrome

OBJECTIVE

Summarize the current knowledge about oxidative stress-related organ dysfunction in inflammatory and septic conditions, and its potential prevention and treatment by antioxidants in critically ill patients, focusing on naturally occurring antioxidants and clinical trials.

STUDY SELECTION

PubMed, MEDLINE, and personal database search.

SYNTHESIS

Plasma concentrations of antioxidant micronutrients are depressed during critical illness and especially during sepsis. The causes of these low levels include losses with biological fluids, low intakes, dilution by resuscitation fluids, as well as systemic inflammatory response syndrome-mediated redistribution of micronutrients from plasma to tissues. Numerous clinical trials have been conducted, many of which have shown beneficial effects of supplementation. Interestingly, among the candidates, glutamine, glutathione, and selenium are linked with the potent glutathione peroxidase enzyme family at some stage of their synthesis and metabolism.

CONCLUSIONS

Three antioxidant nutrients have demonstrated clinical benefits and reached level A evidence: a) selenium improves clinical outcome (infections, organ failure); b) glutamine reduces infectious complication in large-sized trials; and c) the association of eicosapentaenoic acid and micronutrients has significant anti-inflammatory effects. Other antioxidants are still on the clinical benchmark level, awaiting well-designed clinical trials.

Analysis of chemical and metabolic components in traditional Chinese medicinal combined prescription containing Radix Salvia miltiorrhiza and Radix Panax notoginseng by LC-ESI-MS methods

High-performance liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) methods were developed for the analysis of chemical and metabolic components in traditional Chinese medicinal combined prescription containing Radix Salvia miltiorrhiza and Radix Panax notoginseng (commonly known as Fufang Danshen prescription, FDP). The HPLC experiments used a reversed-phase Zorbax C(18) column with the column temperature at 30 degrees C and a binary mobile phase system consisting of aqueous formic acid (0.1%, v/v) and acetonitrile using a gradient elution at the flow rate of 1.0 mL/min. The ESI-MS was operated with a single-quadrupole mass spectrometer in both negative and positive ion modes. 36 major chromatographic peaks of FDP, including 14 saponins, 13 phenolic acids and nine diterpenoid quinones were characterized by their MS spectra and in comparison with some of the reference standards. In addition, after oral administration of extraction of FDP, the rat's plasma, urine and feces were also analyzed; 53 metabolic components including 30 original components and 23 transformative components of FDP were detected, and possible metabolic pathways of some components in FDP were given. The analysis of chemical and metabolic components in FDP by HPLC-MS methods could be a useful means of identifying the multi-components of FDP and to hint at their possible metabolic mechanism of action in the body.