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Two novel strains, designated 11W25H-1T and 8H24J-4-2T, were isolated from surface-sterilized plant tissues collected from the Taklamakan Desert in the Xinjiang Uygur Autonomous Region, China. The strains were characterized by a polyphasic approach in order to clarify their taxonomic positions. They were Gram-stain positive, aerobic, non-motile, non-spore-forming and rod-shaped. The 16S rRNA gene sequences of the strains showed highest similarities with Labedella gwakjiensis KCTC 19176T (99.2% and 98.9%, respectively) and Labedella endophytica CPCC 203961T (98.9% and 99.0%, respectively). The sequence similarity between strains 11W25H-1T and 8H24J-4-2T was 99.4%. Phylogenetic analyses based on 16S rRNA gene sequences and single-copy phylogenetic marker genes (pMGs) showed that the two strains belonged to the genus Labedella and formed a separate cluster from the closest species L. gwakjiensis KCTC 19176T and L. endophytica CPCC 203961T. Genomic analyses, including average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH), clearly separated the strains from each other and from the other species of the genus Labedella with values below the thresholds for species delineation. The two strains showed chemotaxonomic characteristics and phenotypic properties in agreement with the description of the genus Labedella and also confirmed the differentiation from the closest species. The data demonstrated that strains 11W25H-1T and 8H24J-4-2T represented two novel species of the genus Labedella, for which the names Labedella phragmitis sp. nov. (type strain 11W25H-1T = JCM 33144T = CGMCC 1.16700T) and Labedella populi sp. nov. (type strain 8H24J-4-2T = JCM 33143T = CGMCC 1.16697T) are proposed.

Background Apolipoprotein E4 (APOE4) allele is an important risk factor for breast cancer and affects clearance of chylomicron remnants. Tamoxifen therapy increases serum triglyceride levels and sometimes inducing severe hypertriglyceridemia in breast cancer patients. Methods Thirty-three women with breast cancer were recruited to examine the APOE polymorphism and fasting plasma lipid profiles before and after tamoxifen treatment for 6 months. Results We found that plasma lipid profiles changed in accordance with the APOE4 allele after tamoxifen treatment for 6 months. Especially plasma triglyceride levels significantly decreased in the APOE4-positive patients (p = 0.025), while there was no change in APOE4-negative patients (p = 0.189). The total plasma cholesterol levels were reduced in APOE-4 positive patients after 6-month tamoxifen treatment (p = 0.014). The levels of plasma low density lipoprotein cholesterol and high density lipoprotein cholesterol significantly decreased in both APOE4-negative and APOE4-positive patients. Conclusions These findings indicate that the effects of tamoxifen on plasma triglyceride levels are modified by APOE polymorphism. Breast cancer patients with APOE4 allele have low plasma triglyceride levels when receiving tamoxifen therapy. Therefore, we suggest that APOE gene polymorphism is a critical validation before tamoxifen treatment in breast cancer patients.

The effects of different dietary ratios of polyunsaturated fatty acids (PUFAs) and monounsaturated fatty acids (MUFAs) to saturated fatty acids (SFAs) [(PUFA+MUFA)/SFA] on plasma and hepatic lipids, the activities of hepatic regulatory enzymes of cholesterol metabolism, and low-density lipoprotein (LDL) uptake of hepatocytes and Kupffer cells were examined. In this study, 2 different types of diets that had the same PUFA/SFA ratio of 1.0 but each with different (PUFA+MUFA)/SFA ratios of 1.4 (diet 1, control) and 5.7 (diet 2), respectively, were fed to rats. Rats fed with diet 2 showed significantly increased plasma total triacylglycerol (TAG; 21%), very low density lipoprotein (VLDL) TAG (28%), and VLDL cholesterol (113%) levels compared with those fed with diet 1. Plasma LDL cholesterol concentration was not different between the 2 dietary groups of rats. Rats fed with diet 2 also had significantly increased hepatic cholesteryl ester concentrations (155%) and excreted less neutral sterol (35%) compared with rats in the diet 1 group. The activities of hepatic acyl coenzyme A (CoA):cholesterol acyltransferase and cholesterol 7 α -hydroxylase for rats in diet group 2 were significantly increased (38% and 39%, respectively), and hepatic 3-hydroxy-3-methylglutaryl CoA reductase activity decreased (21%) compared with the values in diet group 1. Uptake of LDL by hepatocytes (106%) and Kupffer cells (140%) was higher in rats fed with diet 2 compared with rats fed with diet 1. In summary, the diet with a high ratio (PUFA+MUFA)/SFA increased plasma total TAG, VLDL TAG, and VLDL cholesterol concentrations and liver cholesteryl ester by elevating hepatic acyl CoA:cholesterol acyltransferase and 7 α -hydroxylase activities, lowering hepatic 3-hydroxy-3-methylglutaryl CoA reductase activity, and increasing LDL uptake by hepatocytes and Kupffer cells.

To determine whether high polyunsaturated and monounsaturated fatty acid to saturated fatty acid [(P+M)/S] ratio in diets increases plasma lipoprotein lipids and reduces the hepatic hypertriglyceridemic effect of dietary cholesterol, we compared plasma lipoproteins and liver lipids in 64 rats. Rats were fed diets with the same polyunsaturated fatty acids/saturated fatty acids (P/S) ratio of 1.0, but different (P+M)/S ratios of 1.5, 2, 4, or 5.7 without (experiment 1) or with 1% cholesterol supplement (experiment 2). We found that the plasma total cholesterol (C), and low density lipoprotein (LDL)-C concentrations were significantly higher in rats fed with the (P+M)/S ratio of 5.7 compared with rats fed with the (P+M)/S ratio of 1.5 or 2.0. As to the very low density lipoprotein (VLDL)-C, rats fed with 5.7 or 4.0 ratio had higher concentration than rats fed with 1.5 or 2.0 ratio. With 1% choesterol supplement, when rats were fed with the ratio of (P+M)/S which increased from 1.5, 2, 4 to 5.7, there was a progressive increase in plasma total cholesterol (P=0.0001), total triacylglycerol (TAG, P=0.0091), total phospholipid (PL, P=0.0006), VLDL-C (P=0.0001), VLDL-TAG (P=0.0119), VLDL-PL (P=0.0013), LDL-C (P=0.0001), LDL-TAG (P=0.0006), and LDL-PL (P=0.0001) concentrations. There was also a progressive increase in liver C level (P=0.005) and decrease in liver TAG level (P=0.004) with 1% C supplement. However, without 1% cholesterol supplement, no such a trend was found for plasma total, lipoproteins, and liver lipids. We conclude that high (P+M)/S ratio increases plasma VLDL and LDL lipids and reduces the hepatic hypertriglyceridemic effect of dietary cholesterol in rats. These results suggest that the higher (P+M)/S ratio is more cholesterolemic and hepatocholesterolemic than lower (P+M)/S ratio in rats fed with high-cholesterol diet.