Expression of Nitric Oxide Synthase and Nitric Oxide Levels in Peripheral Blood Cells and Oxidized Low-Density Lipoprotein Levels in Saliva as Early Markers of Severe Dengue.

BACKGROUND: Severe dengue (SD), experienced by only a fraction of dengue patients, can be lethal. Due to the lack of early markers that can predict the evolution of SD, all dengue patients have to be monitored under hospital care. We discovered early oxidative stress markers of SD to identify patients who can benefit from early intervention before the symptoms appear. METHODS: The expression of inducible nitric oxide synthase (iNOS) in peripheral blood cells (PBC), nitric oxide (NO), and oxidized low-density lipoprotein (oxLDL) levels in plasma and saliva collected at early stages of dengue infection from 20 nonsevere dengue fever (DF) patients and 20 patients who later developed SD were analyzed in a retrospective nested case-control study. RESULTS: The expression of iNOS is significantly (P < 0.05) lower in patients who developed SD than in DF patients at admission within 4 days from fever onset. Median plasma NO concentration within 4 days from fever onset is also significantly (P < 0.05) lower in patients who developed SD (17.9 ± 1.6 µmol/L) than DF (23.0 ± 2.1 µmol/L). Median oxLDL levels in plasma within 3 days from fever onset is significantly (P < 0.05) lower in patients who developed SD (509.4 ± 224.1 ng/mL) than DF (740.0 ± 300.0 ng/mL). Median salivary oxLDL levels are also significantly (P < 0.05) lower in patients who developed SD (0.8 ± 0.5 ng/mL) than DF (3.6 ± 2.6 ng/mL) within 4 days from fever onset. CONCLUSIONS: These findings suggest that the expression of iNOS (73% sensitivity, 86% specificity) and plasma NO (96% sensitivity, 61% specificity at 22.3 µmol/L; P < 0.05) may serve as early markers of SD within 3 days from fever onset. Salivary oxLDL levels may serve as early noninvasive markers of SD with a sensitivity and specificity, respectively, of 57% and 91% at 0.9 ng/mL; 76% and 55% at 2.3 ng/mL; and 100% and 50% at 4.6 ng/mL (P < 0.05) within 4 days from fever onset.

Effect of chain length and saturation of the fatty acids in dietary triglycerides on lipid metabolism in Wistar rats.

We investigated the effect of the chain length and the degree of saturation of fatty acids in dietary triglycerides on serum lipid profiles and hepatic lipid metabolism in Wistar rats. Fat component of the basal diet (soybean oil) was replaced with fats with fatty acids of different chain lengths and saturation and the serum lipids were monitored for 150 days. Principal component (PC) analysis of serum lipid components was related to chain length and saturation. The combined effect of chain length and saturation on PC 1 scores was evaluated by multiple regression analysis. The results indicated that average chain length of the fatty acids of triglycerides has a higher influence on the quality of serum lipid parameters than the average degree of saturation. Expression of selected genes responsible for lipid metabolism showed similar trends in medium chain saturated and long chain polyunsaturated diet groups. PRACTICAL APPLICATIONS: Dietary lipids contain a wide range of saturated and unsaturated fatty acids with different chain lengths. Overall contribution of these different fatty acids decides the health effects of the lipids in the diet. Present study shows that the fats with medium chains and higher degree of saturation and fats with long chains and higher degree of unsaturation (lower degree of saturation) affect serum lipid parameters and expression of hepatic genes involved in the lipid metabolism in a similar manner. Such information is important for physicians to plan dietary schemes to improve the nutritional health and manage the noncommunicable diseases.

Differential expression of microRNA, miR-150 and enhancer of zeste homolog 2 (EZH2) in peripheral blood cells as early prognostic markers of severe forms of dengue.

BACKGROUND: Dengue presents a wide clinical spectrum. Most patients recover following a self-limiting non-severe clinical course. A small proportion of patients progress to severe disease, mostly characterized by plasma leakage with or without hemorrhage. Early symptoms of severe dengue (SD) are similar to those of non-severe dengue fever (DF). Severe symptoms manifest after 3-5 days of fever, which can be life threatening due to lack of proper medications and inability to distinguish severe cases during the early stages. Early prediction of SD in patients with no warning signs who may later develop severe infection is very important for proper disease management to alleviate related complications and mortality. microRNA are small non-coding RNA molecules that regulate post-transcriptional gene expression. Due to the remarkable stability and the role of microRNA in gene expression, altered expression of microRNA was evaluated to explore clinically relevant prognostic markers of severe dengue. METHODS: The relative expression of microRNA hsa-let-7e (let-7e), hsa-miR-30b-5p (miR-30b), hsa-miR-30e-3p (miR-30e), hsa-miR-33a (miR-33a), and hsa-miR-150-5p (miR-150) and several putative target genes in peripheral blood cells (PBC) collected from 20 DF and 20 SD positive patients within 4 days from fever onset was evaluated by quantitative reverse transcription PCR (qRT-PCR). RESULTS: miR-150 showed significant (P < 0.01) up regulation in PBC of SD patients compared to DF patients during the acute phase of infection. Expression of enhancer of zeste homolog 2 (EZH2) was significantly (P < 0.01) down regulated indicating that genes involved in epigenetic regulation are also differentially expressed in SD patients during the early stage of infection. CONCLUSIONS: Differential expression of microRNA miR-150 and the putative target gene EZH2 may serve as reliable biomarkers of disease severity during early stages of dengue infection.