Increased renal ANP synthesis, but decreased or unchanged cardiac ANP synthesis in water-deprived and salt-restricted rats

Increased renal ANP synthesis, but decreased or unchanged cardiac ANP synthesis in water-deprived and salt-restricted rats.BackgroundExperiments were performed to examine the effect of water deprivation and salt restriction on ANP synthesis in the kidneys and hearts of normal rats.MethodsA 4-day water deprivation (WD) and 7-day salt restriction (SR; 0.01% NaCl) were performed in 12 and 14 rats, respectively. Atrial natriuretic peptide (ANP) mRNA expression in the kidney was assessed with reverse transcription-polymerase chain reaction coupled with Southern blot hybridization, while the ANP mRNA in the hearts was measured by Northern blot hybridization. ANP and angiotensin II concentrations in the extracted plasma were measured by radioimmunoassay. The molecular form of renal ANP-like protein was characterized by reverse phase—high-performance liquid chromatography (RP-HPLC).ResultsRenal outer and inner medullary ANP mRNA showed a respective 11-fold and ninefold increase in WD rats, and an eightfold and fivefold increase in SR rats as compared to corresponding control groups. Inversely, cardiac atrial ANP mRNA and plasma ANP were decreased in WD rats, whereas they did not change in the SR group. Plasma angiotensin II concentration increased in conjunction with the decrease of urine sodium excretion in both groups. RP-HPLC analysis revealed a 45% extraction of ANP in the WD rat kidneys, whereas only 3% ANP in the control kidneys migrated in a molecular form similar to cardiac atrial proANP.ConclusionsOur results demonstrate that water deprivation and salt restriction markedly enhance renal ANP mRNA, whereas water deprivation suppresses cardiac atrial ANP mRNA and plasma ANP concentrations. The current study indicates that renal ANP and cardiac atrial ANP appear to be two distinct systems regulated by different mechanisms and possibly exhibiting different intra-renal paracrine and systemic endocrine functions

Pioglitazone retrieves hepatic antioxidant DNA repair in a mice model of high fat diet

<p>Abstract</p> <p>Background</p> <p>Pioglitazone was reported to improve hepatic steatosis and necroinflammation in human studies. To investigate whether the hepato-protective effect of pioglitazone was associated with an improvement of antioxidant defense mechanism, oxidative DNA damage and repair activity were determined in a high fat diet model. Male C57BL/6 mice were respectively fed with a 30% fat diet, the same diet with pioglitazone 100 mg/kg/day, or a chow diet as control for 8 weeks. Tissue oxidative stress was indicated by malondialdehyde concentration. Oxidative DNA damage was detected by immunohistochemical 8-oxoG staining. Enzymatic antioxidant defense was detected by the real-time PCR of superoxide dismutase (<it>Sod1, Sod2</it>) and DNA glycosylase (<it>Ogg1, MutY</it>). Oxidative DNA repair was detected by immunohistochemical staining and western blotting of OGG1 expression.</p> <p>Results</p> <p>Our results show that hepatic steatosis was induced by a high-fat diet and improved by adding pioglitazone. Malondialdehyde concentration and 8-oxoG staining were strongly increased in the high-fat diet group, but attenuated by pioglitazone. Gene expressions of antioxidant defense mechanism: <it>Sod1, Sod2, Ogg1 </it>and <it>MutY </it>significantly decreased in the high-fat diet group but reversed by pioglitazone co-administration.</p> <p>Conclusion</p> <p>The attenuation of hepatic oxidative DNA damage by pioglitazone in a high-fat diet may be mediated by up-regulation of the antioxidant defense mechanism and oxidative DNA repair activity. The diminution of oxidative damage may explain the clinical benefit of pioglitazone treatment in patients with non-alcoholic fatty liver disease.</p

Association of ORAI1 Haplotypes with the Risk of HLA-B27 Positive Ankylosing Spondylitis

Ankylosing spondylitis (AS) is a chronic inflammation of the sacroiliac joints, spine and peripheral joints. The aetiology of ankylosing spondylitis is still unclear. Previous studies have indicated that genetics factors such as human leukocyte antigen HLA-B27 associates to AS susceptibility. We carried out a case-control study to determine whether the genetic polymorphisms of ORAI1 gene, a major component of store-operated calcium channels that involved the regulation of immune system, is a susceptibility factor to AS in a Taiwanese population. We enrolled 361 AS patients fulfilled the modified New York criteria and 379 controls from community. Five tagging single nucleotides polymorphisms (tSNPs) at ORAI1 were selected from the data of Han Chinese population in HapMap project. Clinical statuses of AS were assessed by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), and Bath Ankylosing Spondylitis Global Index (BAS-G). Our results indicated that subjects carrying the minor allele homozygote (CC) of the promoter SNP rs12313273 or TT homozygote of the SNP rs7135617 had an increased risk of HLA-B27 positive AS. The minor allele C of 3′UTR SNP rs712853 exerted a protective effect to HLA-B27 positive AS. Furthermore, the rs12313273/rs7135617 pairwise allele analysis found that C-G (OR 1.69, 95% CI 1.27, 2.25; p = 0.0003) and T-T (OR 1.75, 95% CI 1.36, 2.27; p<0.0001) haplotypes had a significantly association with the risk of HLA-B27-positive AS in comparison with the T-G carriers. This is the first study that indicate haplotypes of ORAI1 (rs12313273 and rs7135617) are associated with the risk of HLA-B27 positive AS

In vitro anti-diabetic effect and chemical component analysis of 29 essential oils products

Twenty-nine commercial essential oil (EO) products that were purchased from the Taiwan market, including three different company-made Melissa officinalis essential oils, were assayed on their glucose consumption activity and lipid accumulation activity on 3T3-L1 adipocytes. The EOs of M. officinalis were significantly active in both model assays. By contrast, EOs of peppermint, lavender, bergamot, cypress, niaouli nerolidol, geranium-rose, and revensara did not increase glucose consumption activity from media, but displayed inhibited lipid accumulation activity (65–90% of lipid accumulation vs. the control 100%). Because of the promising activity of M. officinalis EOs, three different products were collected and compared for their gas chromatography chemical profiles and bioactivity. The Western blot data suggest that the key factors of the adenosine monophosphate-activated protein kinase/acetyl-CoA carboxylase pathway can be mediated by M. officinalis EOs. Together with biodata, gas chromatography–mass spectrometry profiles suggested mixtures of citrals and minor compounds of M. officinalis EOs may play an important role on effect of antidiabetes

DAD fingerprint of an analyzed sample of mulberry leaf extract together with the chromatograms at λ = 326.3 nm (used for determination of 1) and λ = 353.0 nm (used for determination of 2 and 3) and UV spectra of each compound (Fig. 2A), and results of the peak purity testing for compounds 1–3 (Fig. 2B).

<p>In <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0050619#pone-0050619-g002" target="_blank"><b>Fig. 2B</b></a>, peak areas where purity was found over 99.9% (green) are represented as mean of percentages ± SD; n = 3.</p