Mycobacteria store triacylglycerols (TGs) in the form of intracellular lipid droplets (LDs) during hypoxia-induced nonreplicating persistence. These bacteria are phenotypically drug-resistant and therefore are believed to be the cause for prolonged tuberculosis treatment. LDs are also associated with bacilli in tuberculosis patient sputum and hypervirulent strains.
View Article and Find Full Text PDFZhongguo Zhong Yao Za Zhi
February 2010
In the trials of multi-glycoside of Tripterygium wilfordii (GTW) in the field of pharmacodynamics, some clinical characteristics and symptoms, such as proteinuria, hematuria,joint pain, and skin damage, could be improved in the patients with various diseases including proliferative glomerulonephritis, lupus nephritis, rheumatoid arthritis, psoriasis and other immune-related diseases. In this review, it has been also reported to discuss the effects of GTW and Triptolide (T4), which is a bioactive component in GTW on anti-inflammatory, immunosuppression, and protection of epithelial cell in kidney. On the other hand, it is possible to have some beneficial effects on organ transplant rejection, tumor growth and anti-fertility.
View Article and Find Full Text PDFDespite apolipoprotein E's important role in cholesterol transport and metabolism in the brain as well as its influence on Alzheimer's disease, the impact of the human APOE genotype on cholesterol metabolism in brain has not been fully examined. This study was carried out to investigate APOE genotype effects on oxysterols measured. In this study the measurement of cholesterol and several oxysterols in the brains of human APOE epsilon2, epsilon3 and epsilon4 knock-in mice at 8 weeks and 1 year of age using gas chromatography mass spectrometry (GC-MS) demonstrated no APOE genotype or age effect on total brain cholesterol and the oxysterol 24-hydroxycholesterol.
View Article and Find Full Text PDFIt is known that apolipoprotein E (ApoE) is essential for normal lipid metabolism. ApoE is the major apolipoprotein in the central nervous system and plays a key role in neurobiology by mediating the transport of cholesterol, phospholipids, and sulfatides. We therefore examined APOE epsilon2, epsilon3, and epsilon4 knock-in mice, using electrospray ionization mass spectrometry to determine if APOE genotype or age leads to altered levels in the brain of a number of glycerophospholipids (phosphatidylinositol, PI; phosphatidylethanolamine, PE; phosphatidic acid, PA, phosphatidylserine, PS; phosphatidylcholine, PC), sphingolipids (sphingomyelin, SM; ceramide, Cer), cholesterol, and triacylglycerols.
View Article and Find Full Text PDFA group of phosphoinositide 3-kinase (PI3K) inhibitors, such as 3-methyladenine (3-MA) and wortmannin, have been widely used as autophagy inhibitors based on their inhibitory effect on class III PI3K activity, which is known to be essential for induction of autophagy. In this study, we systematically examined and compared the effects of these two inhibitors on autophagy under both nutrient-rich and deprivation conditions. To our surprise, 3-MA is found to promote autophagy flux when treated under nutrient-rich conditions with a prolonged period of treatment, whereas it is still capable of suppressing starvation-induced autophagy.
View Article and Find Full Text PDFPhosphate is an essential nutrient for plant viability. It is well-established that phosphate starvation triggers membrane lipid remodeling, a process that converts significant portion of phospholipids to non-phosphorus-containing galactolipids. This remodeling is mediated by either phospholipase C (PLC) or phospholipase D (PLD) in combination with phosphatidate phosphatase (PAP).
View Article and Find Full Text PDFThe accumulation of misfolded secreted IgM in the endoplasmic reticulum (ER) of X-box binding protein 1 (XBP-1)-deficient B cells has been held responsible for the inability of such cells to yield plasma cells, through the failure to mount a proper unfolded protein response. LPS-stimulated B cells incapable of secreting IgM still activate the XBP-1 axis normally, as follows: XBP-1 is turned on by cues that trigger differentiation and not in response to accumulation of unfolded IgM, but the impact of XBP-1 deficiency on glycoprotein folding and assembly has not been explored. The lack of XBP-1 compromised neither the formation of functional hen egg lysozyme-specific IgM nor the secretion of free kappa-chains.
View Article and Find Full Text PDFBurkholderia pseudomallei, the etiological agent of melioidosis, is a facultative intracellular pathogen. As B. pseudomallei is a gram-negative bacterium, its outer membrane contains lipopolysaccharide (LPS) molecules, which have been shown to have low-level immunological activities in vitro.
View Article and Find Full Text PDFZhongguo Zhong Yao Za Zhi
April 2009
The pathomechanisms of the progression of chronic kidney disease (CKD) include glomerulosclerosis, renal interstitial fibrosis and renal arteriosclerosis. Chinese herbal medicine can delay the progression of CKD by ameliorating the harmful factors of these pathological changes, such as podocyte and slit diaphragm injury, nephrotoxicity of proteinuria, hyperactivity of renin-angiotensin-aldosterone system, cytokines over-expression, tubular epithelial myofibroblast transdifferentiation, hyperlipidemia and hypertension.
View Article and Find Full Text PDFMycobacteria store triacylglycerols (TGs) under various stress conditions, such as hypoxia, exposure to nitric oxide, and acidic environments. These stress conditions are known to induce nonreplicating persistence in mycobacteria. The importance of TG accumulation and utilization during regrowth is not clearly understood.
View Article and Find Full Text PDFVery long-chain polyunsaturated fatty acids (VLC-PUFAs), such as docosahexaenoic acid (DHA) and docosapentaenoic acid (DPA), have recently made it to the realm of "magical molecules" based on their multiple presumably beneficial effects in biological systems, making these PUFAs particularly interesting in biomedicine. Their specific biological functions, however, remain enigmatic. Here we provide evidence derived from studies in the amoeba Chaos that indicates a structural role for omega-6 DPA in cell membrane organization, which may help to explain the multiple diverse effects of VLC-PUFA in healthy and diseased states.
View Article and Find Full Text PDFRecently, there has been considerable interest in a possible link between changes in brain polyunsaturated fatty acids, neural membrane phospholipid degradation, serotonergic neurotransmission, and depression. The present study aims to examine effects of antidepressants on lipids in different regions of the brain at individual molecular species level, using the novel technique of lipidomics. Balb/C mice received daily intraperitoneal (i.
View Article and Find Full Text PDFThe mitochondrial inner membrane contains different translocator systems for the import of presequence-carrying proteins and carrier proteins. The translocator assembly and maintenance protein 41 (Tam41/mitochondrial matrix protein 37) was identified as a new member of the mitochondrial protein translocator systems by its role in maintaining the integrity and activity of the presequence translocase of the inner membrane (TIM23 complex). Here we demonstrate that the assembly of proteins imported by the carrier translocase, TIM22 complex, is even more strongly affected by the lack of Tam41.
View Article and Find Full Text PDFRetroviruses acquire a lipid envelope during budding from the membrane of their hosts. Therefore, the composition of this envelope can provide important information about the budding process and its location. Here, we present mass spectrometry analysis of the lipid content of human immunodeficiency virus type 1 (HIV-1) and murine leukemia virus (MLV).
View Article and Find Full Text PDFUnderstanding the mechanisms underlying lipid-induced cell death has significant implications in both cell biology and human diseases. Previously, we showed that fission-yeast Schizosaccharomyces pombe cells deficient in triacylglycerol synthesis display apoptotic markers upon entry into stationary phase. Here, we characterize the sequential molecular events that take place at the onset of cell death in S.
View Article and Find Full Text PDFLipid droplets (LDs) are emerging cellular organelles that are of crucial importance in cell biology and human diseases. In this study, we present our screen of approximately 4,700 Saccharomyces cerevisiae mutants for abnormalities in the number and morphology of LDs; we identify 17 fld (few LDs) and 116 mld (many LDs) mutants. One of the fld mutants (fld1) is caused by the deletion of YLR404W, a previously uncharacterized open reading frame.
View Article and Find Full Text PDFHere, we present an improved method for sensitive profiling of lipids in a single high-performance liquid chromatography-electrospray ionization-quadrupole time of flight mass spectrometry experiment. The approach consists of i) sensitive isocratic elution, which takes advantage of C18 column material that is resistant to increased pH values induced by piperidine, ii) chemometric alignment of mass spectra followed by differential analysis of ion intensities, and iii) semiquantitative analysis of extracted ion chromatograms of interest. A key advantage of this method is its wide applicability to extracts that harbor lipids of considerable chemical complexity.
View Article and Find Full Text PDFSoy sauce is a traditional fermented seasoning in Asian countries, that has high antioxidant activity in vitro and some antioxidant activity in vivo. We attempted to identify the major antioxidants present, using the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay as a guide. 3-Hydroxy-2-methyl-4H-pyran-4-one (maltol) was one of several active compounds found in an ethyl acetate extract of dark soy sauce (DSS) and was present at millimolar concentrations in DSS.
View Article and Find Full Text PDFKainate is a glutamate analog that has been widely used in pharmacological studies of neuronal injury related to ischemic conditions and epilepsy. While altered lipid metabolism has been implicated in kainate action, no study has yet investigated the associated changes in lipid metabolites on a systems scale. Here we describe a mass spectrometry-based approach for profiling of lipid mixtures in a nontargeted fashion.
View Article and Find Full Text PDFCell adhesion and spreading is a crucial step in the metastatic cascade of cancer cells, and interruption of this step is considered to be a logical strategy for prevention and treatment of tumor metastasis. Emodin is the major active component of the rhizome of Rheum palmatum L., with known anticancer activities.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
November 2005
Ulam raja (Cosmos caudatus) is used traditionally for improving blood circulation. In this study, it was found that ulam raja had extremely high antioxidant capacity of about 2,400 mg l-ascorbic acid equivalent antioxidant capacity (AEAC) per 100 g of fresh sample. Antioxidant peaks in extract of ulam raja were firstly characterized using free radical spiking test through high performance liquid chromatography coupled with mass spectrometry (MS).
View Article and Find Full Text PDFIn this study, a new approach was developed for screening and identifying antioxidants in biological samples. The approach was based on significant decreases of the intensities of ion peaks obtained from high-performance liquid chromatography (HPLC) coupled with mass spectrometry (MS) upon reaction with 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radicals. HPLC-MS/MS was further applied to elucidate structures of antioxidant peaks characterized in a spiking test.
View Article and Find Full Text PDFAntioxidants found in fruits and vegetables play an important role via their protective effects against the onset of aging-related chronic diseases. Our previous research has indicated that unripe ciku fruits (Manilkara zapota L.) are an excellent source of antioxidants, with over 3000 mg of L-ascorbic acid equivalent antioxidant capacity (AEAC) per 100 g of fresh sample.
View Article and Find Full Text PDFJ Chromatogr A
September 2004
Major antioxidants of aqueous ethanol extract from Lady's Finger (Hibiscus esculentus Linn) were systematically investigated in this study. Firstly, high-performance liquid chromatography (HPLC) was applied to identify antioxidant peaks in a sample by spiking the sample extract with 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical, which was prepared from manganese dioxide and ABTS. Secondly, in order to identify the elution period of major antioxidant peaks, the antioxidant capacities of different fractions from solid-phase extraction (SPE) were measured, and the chromatograms of fractions were also recorded.
View Article and Find Full Text PDFOur previous study indicated that star fruit (Averrhoa carambola L.) is a very good source of natural antioxidants. However, it was still not clear which compounds were responsible for its antioxidant properties.
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