Ghrelin, Nitrite and Paraoxonase/Arylesterase Concentrations in Cement Plant Workers

Occupational cement dust exposure has been associated with an increased risk of liver abnormalities, pulmonary disorders, and carcinogenesis. Decreased antioxidant capacity and increased plasma lipid peroxidation have been posed as possible causal mechanisms of disease. Accordingly, this study examined the serum paraoxonase (PON1) arylesterase (AE), ghrelin, HDL-C, LDL-C and serum nitrite (NOx) levels in cement dust exposed workers. Twenty-eight volunteer male cement plant workers and 30 volunteer control male workers, aged 29-54 years, participated. The concentrations of serum PON1, AE, NOx, ghrelin, and HDL-cholesterol and LDL-cholesterol were measured in both groups. PON-1, AE, ghrelin and HDL-cholesterol were lower in the cement plant workers than in controls. Serum nitrite (NOx), and LDL-C levels in cement plant workers were higher (p<0.05) than in the control group workers. No correlation was observed between the serum levels of HDL-cholesterol and PON1 and between HDL-cholesterol and ghrelin. A weak negative correlation was detected between the serum ghrelin and NOx. The study results strongly suggest that HDL-paraoxonase, AE, ghrelin, HDL-C, and high NOx, and LDL-C levels may have a role in disease involving oxidative damage. However, some studies are necessary to address the association between occupational dust exposure and respiratory symptoms.

Simultaneous quantification of acylated and desacylated ghrelin in biological fluids

This study reports simultaneous quantification of both acylated and desacylated forms of ghrelin in biological samples, utilizing a reverse-phase high-performance liquid chromatography (HPLC) system. The HPLC assay was also compared with RIA assays in use. Biological samples (serum, saliva, urine, milk) known for the presence of ghrelin were collected from a total of eight post-partum women and eight male volunteers. Analysis of ghrelin with HPLC was also validated for linearity, precision, detection limit and accuracy. An elution time of 6 min was observed for pure (commercial) desacylated human ghrelin and for the same form of the hormone from all body fluids studied. The elution time for acylated pure human ghrelin and that in body fluids, however, was around 16 min. The mean recovery rate was over 90% for both forms with no significant interference. The lowest detectable levels for acylated and desacylated ghrelin with the method used here were 11 (+/-2) and 14 (+/-3) pg mL(-1), respectively. Given its simplicity, accuracy, time and cost-effectiveness, the HPLC method described here for determination of two forms of ghrelin (active and inactive) might prove useful for certain diagnostic purposes.

Ghrelin in plants: what is the function of an appetite hormone in plants?

In the present work, we provide compelling evidence for the expression of a ghrelin-like peptide hormone that has only been associated with animals, in various plant tissues. Ghrelin, the appetite stimulating hormone, has been identified from a number of different species including humans, rat, pig, mouse, gerbil, eel, goldfish, bullfrog and chicken. The study here was conducted using an immunohistochemistry assay to screen whether plants have any ghrelin immunoreactivity. In this respect, Prunus x domestica L. and Marus alba were examined. Immunohistochemistry results showed that there is a strong human ghrelin immunoreactivity substance in the parenchyma cells of these plants. This was entirely unexpected since this hormone was considered to be present solely in animals. Thus, this study is the first to report the presence of a peptide with ghrelin-like activity in plants, a finding that has only been observed in the animal kingdom. RIA analysis confirmed that these plants contain significant amounts of this substance. Furthermore, reverse-phase HPLC analyses of plant extracts showed an elution characteristic of the peptide identical to that of human ghrelin. In general, fruit from both plants had higher levels of the peptide than the vegetative parts.

The Past and Present of Paraoxonase Enzyme: Its Role in the Cardiovascular System and Some Diseases

Although paraoxonase is synthesized in many tissues including the heart, colon, kidneys, lungs, small intestines and brain, its major locus of synthesis is the liver. PON1 is in close association with apolipoproteins and protects LDL against oxidation. It was reported that PON1 quantities dropped to 40 times lower than normal in cardiovascular diseases and diseases like diabetes, ulcerative colitis, Crohn's disease, chronic renal failure, SLE, Behcet's disease, cancer, hepatitis B, obesity, metabolic syndrome, Alzheimer's and dementia. It is speculated that the concerning decline in serum PON1 amount results from single nucleotide polymorphism in the coding (Q192R, L55M) and promoter (T-108C) sites of the PON1 gene. Additionally, circulating amounts of PON1 are affected by vitamins, antioxidants, fatty acids, dietary factors, drugs, age and lifestyle. This collection attempts to review and examine the past and present studies of paraoxonase and its relation with the cardiovascular system and some relevant diseases.

Effects of Sodium Octanoate, Acylated Ghrelin, and Desacylated Ghrelin on the Growth of Genetically Engineered Escherichia Coli

Acylated ghrelin is a 28-amino acid peptide hormone bearing a fatty acid group based on octanoic acid (caprylic acid) at the serine which is located at position 3 and at the N-terminus. If this fatty acid is cleaved from acylated ghrelin, the remaining peptide is referred to as desacylated ghrelin. Free fatty acids (FFAs) can kill or inhibit the growth of bacteria. The purpose of this study was to test this ability using acylated ghrelin, desacylated ghrelin, and sodium octanoate (caprylic acid) as carbon sources for the genetically engineeredEscherichia colistrains MK79 and MK57. For this experimental work, minimal medium was modified by replacing glucose with equal concentrations of acylated ghrelin, desacylated ghrelin, or sodium octanoate. Bacterial optical density, viability, alpha-amylase production, plasmid stability and pH of the growth medium were measured during these experiments. The media that allowed most growth, based on viable cell counts and the OD600of MK79, was minimal medium, followed by the medium containing desacylated ghrelin or acylated ghrelin, and finally the medium containing sodium octanoate. The same order was observed for MK57. Neither of the strains lost plasmids during the entire course of each experiment. There was also little change in the pH of any of the media used for both strains. These results suggest that sodium octanoate, acylated ghrelin, and desacylated ghrelin, when compared with minimal medium, inhibitEscherichia coligrowth. Proliferation was lowest when sodium octanoate was used as the carbon source, followed by acylated ghrelin and desacylated ghrelin. Therefore, the acylated ghrelin found previously in human saliva might help to inhibit pathogenic microorganisms, and acylated ghrelin levels below a critical concentration in saliva could result in an increased risk of oral infection.

Effects of iloprost and sildenafil treatment on elabela, apelin-13, nitric oxide, and total antioxidant and total oxidant status in experimental enzyme-positive acute coronary syndrome in rats

Despite significant advances in medicine, mortality due to cardiovascular disease is not yet preventable. We investigated the amounts of elabela (ELA) and apelin, synthesized by cardiomyocytes, and changes of these compounds in cardiac tissue and circulation after administration of iloprost (ILO) and sildenafil (SIL) in rats with induced myocardial ischemia (MI). We also investigated a connection with circulating troponin-I, creatine kinase (CK), creatine kinase-myocardial band (CK-MB) and nitric oxide (NO), and total anti-oxidant (TAS)/total oxidant status (TOS). We established eight study groups of five rats each. Group 1, sham, was given only physiologic serum; group 2, ILO; group 3, SIL; group 4, ILO + SIL; group 5, MI; group 6, MI + ILO; group 7, MI + SIL; group 8, MI + ILO + SIL. Troponin-I, CK, CK-MB and TAS-TOS were investigated using an autoanalyzer. NO, ELA and apelin were analyzed by ELISA. Tissue apelin and ELA expressions and localizations were determined by immunohistochemistry. The MI group compared to the control (sham) group showed that ELA, apelin, troponin-I, CK, CK-MB, NO and TOS levels were elevated significantly. Concentrations of these factors increased in MI, but decreased after ILO and SIL administration. The largest decrease of TOS was identified in the ILO + SIL group. ELA and apelin may be novel indicators of MI and administration of ILO and SIL, individually or together, may be useful for treating MI.

Immunohistochemical and quantitative analysis of ghrelin in Syzygium aromaticum

Ghrelin, an endogenous ligand of the growth hormone secretagogue receptor, has been identified in mammals, fish, amphibians, birds, reptiles and some plants. The present investigation was designed to determine whether ghrelin is present in the appetite-stimulating plants Syzygium aromaticum and Salvadora persica, using IHC (immunohistochemistry) to indicate the location of the peptide and ELISA to measure the concentration. ELISA demonstrated that a ghrelin-like substance was present at concentrations of 4070.75±664.67 and 75.25±24.49 pg/mg in the tissues of flower bud of S. aromaticum and branch of S. persica, respectively. The concentration of ghrelin in human salivary gland tissue was 436.00±95.83 pg/mg. Ghrelin was predominantly localized to the T (trachea) and PCs (parenchyma cells) in the flower bud of S. aromaticum. However, no ghrelin immunoreactivity was observed in the PC or T of the branch of S. persica. The evolutionary role of this peptide hormone in plants and animals suggests that they have evolved in a more similar way than previously thought.

Menadione knocks out Vitreoscilla haemoglobin (VHb): the current evidence for the role of VHb in recombinant Escherichia coli

Genetically engineering the heterologous bacterial host with the gene (vgb) encoding Vitreoscilla haemoglobin (VHb) has been found to provide typical advantages in growth and production, and it has generally been assumed that VHb is responsible for this effect. Here, using matched strains of Escherichia coli that bear a recombinant R-amylase gene (MK57) or the R-amylase gene and vgb (MK79), we examined this assumption. Menadione, which is known to oxidize haem proteins, was tested over a range of concentrations for its effects on growth, R-amylase production, respiration and VHb function in MK57 and MK79. Active VHb accumulated, and VHb was oxidized to the inactive ferric form with the use of menadione at the concentrations of 0.5-10 mM; concentrations that had a much smaller effect on cytochrome oxidase. This decrease in active VHb in strain MK79 was correlated with a reverse in the advantage regarding R-amylase production of MK79 over MK57 seen at a menadione concentration of 0 mM, thus linking the presence of active VHb with the increase in R-amylase production. It is concluded that vgb, and not any other Vitreoscilla DNA sequences on plasmid pMK79, is the source of the advantages in both the growth and product production of alpha-amylase in this system.

Antioxidant status, alpha-amylase production, growth, and survival of hemoglobin bearing Escherichia coli exposed to hypochlorous acid

In the present work, two matched strains of E. coli that bear a recombinant R-amylase gene (MK57) or the R-amylase gene and vgb (MK79-hemoglobin expressing strain) were exposed to HOCl. In these cells, glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), alpha-amylase production, growth and lethality were assessed in the presence and absence of HOCl. It was observed that the hemoglobin makes cells highly susceptible to killing by HOCl. The maximum survival for both strains was with stationary phase cells at any concentration of HOCl. Both strains grown in the presence of 0.0125-0.075 mg/liter HOCl showed a substantial increase in SOD activity and GSH level, with MK79 being the most increased strain in this respect, while the level of CAT activity was decreased in a dose depended manner. Growth of MK57 and MK79 strains decreased as HOCl concentration increased. However, HOCl at concentration above zero enhanced alpha-amylase production (about 2-fold) in both MK79 and MK57. Furthermore, total amylase production (at all HOCl concentrations) by MK79 was always greater than that by MK57. The results indicate that except for survival, the hemoglobin helps cells to grow better and produces more recombinant products and activates general defense systems more in response to oxidative stress when compared with the non-hemoglobin-containing counterpart.

Blood, saliva and urine maresin-1 and malondialdehyde may be useful biomarker in patients with polycystic ovary syndrome: a prospective study

Background: Maresin-1 (MaR1) plays a major role in many inflammatory disorders. Polycystic ovary syndrome (PCOS) aside from a hormonal disorder, an inflammation might also contribute to PCOS and its metabolic associations. Therefore, the purpose of this prospective study first time was to find out the blood, saliva and urine levels of MaR1 in PCOS patients and evaluate the correlations with other metabolic and hormonal parameters. Methods: Thirty PCOS patients and 30 matched healthy controls were enrolled to prospective case control study. Blood, urine and saliva samples were simultaneously collected from participants after overnight fasting. MaR1 levels in blood, urine and saliva samples were determined by enzyme-linked immunosorbent assay. Ferriman-Gallwey score, anthropometric, hormonal and some other metabolic parameters were also recorded. Regression analysis was preformed to find out the relationship between MaR1, C-reactive protein (CRP) and malondialdehyde (MDA), and hormonal and metabolic parameters. Results: Patients with PCOS compared with control women had higher MDA and CRP and decreased MaR1 levels. Blood, urine and saliva MDA and MaR1 levels were similar and indicated parallel decrease or increase in the PCOS and control groups. Furthermore, regression analysis indicated that blood CRP and MDA was positively associated with luteinizing hormone (LH) and fasting insulin (FI) in PCOS group (p < 0.05) while blood, urine and saliva MaR1 was negatively associated with CRP and MDA. Conclusions: Present results (MaR1, CRP and MDA together) in case of PCOS suggests that decreased MaR1 and elevated MDA and CRP levels in patients with PCOS and may be considered as a useful early biomarker (especially MaR1) in diagnosis of PCOS disease that has not been previously reported and regular monitoring of their levels could be helpful in clinical decisions.