Incorporation of branched-chain fatty acid into cellular lipids and caspase-independent apoptosis in human breast cancer cell line, SKBR-3

BACKGROUND: 13-Methyltetradecanoic acid (13-MTD), an iso-C15 branched- chain saturated fatty acid, has been shown to induce apoptotic cell death of numerous human cancer cells. However, the mechanism for the induction of apoptosis has not been fully understood. This study described the incorporation of 13-MTD into cellular lipid of SKBR-3 breast cancer cells and apoptosis related event to gain more insight into the mechanism action of this fatty acid. RESULTS: Treatment of SKBR-3 cells with 13-MTD lowered the cell viability and induced apoptosis. Proportion of 13-MTD in the glycerolipids increased to saturation level within 6 hours. Triacylglycerol contained 13-MTD in higher concentration than phospholipid with positional preference to sn-2. 13-MTD caused no changes in the caspase activity and its gene expression. Furthermore, addition of caspase-inhibitor to culture medium did not prevent the cells from the cytotoxicity of 13-MTD. No-increase in the cellular calcium level was also noted with 13-MTD treatment. However, 13-MTD disrupted the mitochondrial integrity in 4 hours, and increased the nuclear translocation of apoptosis inducing factor. CONCLUSION: These results showed that 13-MTD disrupted the mitochondrial integrity, and induced apoptosis via caspase-independent death pathway

Salicylic Acid: An All-Rounder in Regulating Abiotic Stress Responses in Plants

Salicylic acid (SA) is an endogenous growth regulator of phenolic nature and also a signaling molecule, which participates in the regulation of physiological processes in plants such as growth, photosynthesis, and other metabolic processes. Several studies support a major role of SA in modulating the plant response to various abiotic stresses. It is a well-founded fact that SA potentially generates a wide array of metabolic responses in plants and also affects plant-water relations. This molecule also found to be very active in mitigating oxidative stress under adverse environmental conditions. Since abiotic stress remained the greatest constraints for crop production worldwide, finding effective approaches is an important task for plant biologists. Hence, understanding the physiological role of SA would help in developing abiotic stress tolerance in plants. In this chapter, we will shed light on the recent progress on the regulatory role of SA in mitigating abiotic stress

Approaches to Enhance Salt Stress Tolerance in Wheat

Wheat is consumed as a staple food by more than 36% of world population. Wheat provides nearly 55% of the carbohydrates and 20% of the food calories consumed globally. The productivity of wheat is often adversely affected by salt stress which is associated with decreased germination percentage, reduced growth, altered reproductive behavior, altered enzymatic activity, disrupted photosynthesis, damage of ultrastructure of cellular components, hormonal imbalance, and oxidative stress. Different approaches have been adopted to improve plant performance under salt stress: introduction of genes, screening of better performing genotypes, and crop improvement through conventional breeding methods which are often not so successful and suitable due to time-consuming or reduction of plant vigor with the succession of time. Uses of exogenous phytoprotectants, seed priming, nutrient management, and application of plant hormone are convenient for improving plant performances. This chapter reviews the mechanism of damage of wheat plants under salt stress and also the recent approaches to improve growth and productivity of salt-affected wheat plants emphasizing the use of exogenous phytoprotectants from the available literature

Salinity Alters the Polyisoprenoid Alcohol Content and Composition of Both Salt-Secreting and Non–Salt-Secreting Mangrove Seedlings

The effects of salinity on the polyisoprenoid alcohol content and composition of the salt-secreting mangrove species Avicennia marina and Sonneratia alba and the non–salt-secreting species Bruguiera gymnorrhiza and Kandelia obovata were studied. The seedlings of mangroves were grown for 5 months under 0% and 3% salt concentrations. The occurrence, content, and distribution of four mangrove seedlings were analyzed by two-dimensional thin layer chromatography. The structural groups of the polyprenols and dolichols in the leaves and roots were classified into two types (I and II). In type I, dolichols predominated over polyprenols (more than 90%), whereas in type II, the occurrence of both polyprenols and dolichols was observed. Polyprenols were not detected in the leaves of A. marina and B. gymnorrhiza under 0% salt (control), but were detected in small amounts in K. obovata leaves; however, significant amounts were found in the 3% salinity group. This finding in A. marina, B. gymnorrhiza, and K. obovata leaves implies a change to the structural group: under 0% salt concentrations, the groups are classified as type I, but become type II under 3% salt concentrations. The occurrence of ficaprenol (C50–55) was found only in the leaves of the non–salt-secreting species B. gymnorrhiza and K. obovataunder 3% salinity and not in the salt-secreting species A. marina or S. alba. It is noteworthy that the polyisoprenoid type in the roots of the four species showed no change under salinity; the two salt-secreting species A. marina and S. alba contained type I under 0% and 3% salt concentrations. On the other hand, type II polyisoprenoids were identified in the non–salt-secreting species B. gymnorrhiza and K. obovata under 0% and 3% salinity conditions. This finding suggested that polyisoprenoids play a protective role against salinity in the mangrove leaves of both salt-secreting and non–salt-secreting species

Effect of purified soluble polysaccharides extracted from gray oyster mushroom [Pleurotus sajor-caju (Fr.) Sing.] on 3t3-L1 adipocytes

Functional mushroom polysaccharides have been known to the Asian traditional medicine for many years. The anti-obesity activity of mushroom polysaccharides has been illustrated both in vivo and in vitro. However, the effect of pure polysaccharides on isolated fat cells has not been demonstrated. In this study, we used hot water and ammonium oxalate to extract polysaccharides from gray oyster mushroom [Pleurotus sajor-caju (Fr.) Sing.] and subsequently purified with enzymatic digestion, solvent extraction and ion-exchange chromatography. One of the fractions, 7S1-1, has the highest yield and purity and contains polysaccharides with the molecular weight around 500 kDa. In addition, Fourier transformed infrared spectroscopy (FTIR) and monosaccharide composition analyses showed that this 7S1-1 sample contains mostly β-glucan and some mannan. We find that the 7S1-1 fraction does not affect the total amount of triglycerides in the 3T3-L1 adipocytes but promotes a release of glycerol of the fat cells, suggesting that the fraction does not inhibit adipogenesis but stimulates lipolysis. Laminarin, a small β-glucan, confers similar results to the 7S1-1 sample, but it could not stimulate lipolysis as well as the 7S1-1 sample. Therefore, these results suggest a potential anti-obesity activity of the mushroom polysaccharides

Morphological and Biochemical Evaluation of the Induction of Atherosclerosis in Japanese Quails

A total of 77 birds were divided into 7 groups which were fed the following diets : Group I, basal ; Group II, 5% corn oil (CO) + 0.5% cholesterol (CH) ; Group III, 5% CO + 2% CH; Group IV, 5% CO + 4% CH; Group V, 15% CO + 0.5% CH ; Group V I, 15% CO + 2% CH; Group VII, 15% CO + 4% CH. Significant increase of serum lipid, accumulation of lipid in the liver, and lipid-rich aortic lesions were produced in Groups IV, VI and VIII. However, hyperlipidemia correlated well with the extent of hepatic lipid accumulation and severity of aortic atherosclerosis in Group VI. Proliferating intimal cells showed positive reaction to antibodies for vimentin and alpha-1-antichymotrypsin implicating an important role of phenotypical transformation of intimal cells from the medial fibroblastic cells in the development of aortic atherosclerosis. These results suggest that Japanese quail is highly susceptible to atherosclerosis, and the optimal dietary level of cholesterol and corn oil is 2% and 15%, respectively to induce lipid-rich aortic lesions in Japanese quail

Tumor-selective cytotoxicity of nitidine results from its rapid accumulation into mitochondria

We identified a nitidine- (NTD-) accumulating organelle and evaluated the net cytotoxicity of accumulated NTD. To evaluate tumor cell selectivity of the drug, we evaluated its selective cytotoxicity against 39 human cancer cell lines (JFCR39 panel), and the profile was compared with those of known anticancer drugs. Organelle specificity of NTD was visualized using organelle-targeted fluorescent proteins. Real-time analysis of cell growth, proliferation, and cytotoxicity was performed using the xCELLigence system. Selectivity of NTD in the JFCR39 panel was evaluated. Mitochondria-specific accumulation of NTD was observed. Real-time cytotoxicity analysis suggested that the mechanism ofNTD-induced cell death is independent of the cell cycle. Short-termtreatment indicated that this cytotoxicity only resulted from the accumulation of NTD into the mitochondria. The results from the JFCR39 panel indicated that NTD-mediated cytotoxicity resulted fromunique mechanisms compared with those of other known anticancer drugs. These results suggested that the cytotoxicity of NTD is only induced by its accumulation in mitochondria.Thedrug triggered mitochondrial dysfunction in less than 2 h. Similarity analysis of the selectivity of NTD in 39 tumor cell lines strongly supported the unique tumor cell specificity of NTD. Thus, these features indicate that NTD may be a promising antitumor drug for new combination chemotherapie

Microsatellite analysis of genetic diversity and structure of Bruguiera gymnorrhiza and Kandelia obovate

Microsatellite loci were used for estimating genetic diversity and structure for three populations of B. gymnorrhiza and K. obovata (Rhizophoracea) in Okinawa, Japan. Thirty propagules of individual samples representing the population of both species were genotyped at five microsatellites. The level of observed heterozygosity (HO) was observed for several population, overall loci, ranged 0.422-0.800 with an average 0.627 for B. gymnorrhiza and 0.477-0.822 with an average 0.665 for K. obovata, indicating both species had relatively low genetic diversity. Both species showed low levels of allelic diversity, 3-5 and 3-5 alleles per locus, respectively. Gene diversitywas also maintained within populations (HS: 0.741 and 0.954). Additionally, an analysis of molecular variance (AMOVA) based on the immeasurable alleles model (F-statistics), for B. gymnorrhiza and K. obovata found that most of the variation resided within individuals in the total populations, i.e. 79.78 % and 69.90 % respectively, and among individuals within populations, i.e.14.30 % and 27.95 % respectively. There was little variation between populations, i.e. 5.92 % and 2.15 % for B. gymnorrhiza and K. obovata, respectively. The high-level genetic differentiation within individuals and populations both species may be due to the geographic range of the species, mating system, and environmental factors