Autophagy and the nutritional signaling pathway

During their growth and development, animals adapt to tremendous changes in order to survive. These include responses to both environmental and physiological changes and autophagy is one of most important adaptive and regulatory mechanisms. Autophagy is defined as an autolytic process to clear damaged cellular organelles and recycle the nutrients via lysosomic degradation. The process of autophagy responds to special conditions such as nutrient withdrawal. Once autophagy is induced, phagophores form and then elongate and curve to form autophagosomes. Autophagosomes then engulf cargo, fuse with endosomes, and finally fuse with lysosomes for maturation. During the initiation process, the ATG1/ULK1 (unc-51-like kinase 1) and VPS34 (which encodes a class III phosphatidylinositol (PtdIns) 3-kinase) complexes are critical in recruitment and assembly of other complexes required for autophagy. The process of autophagy is regulated by autophagy related genes (ATGs). Amino acid and energy starvation mediate autophagy by activating mTORC1 (mammalian target of rapamycin) and AMP-activated protein kinase (AMPK). AMPK is the energy status sensor, the core nutrient signaling component and the metabolic kinase of cells. This review mainly focuses on the mechanism of autophagy regulated by nutrient signaling especially for the two important complexes, ULK1 and VPS34.     

Therapeutic effects of biguanide vs. statin in polycystic ovary syndrome: a randomized clinical trial

Various classes of medication are currently being used in Polycystic Ovary Syndrome (PCOS) patients including the biguanides and the statins. However, their efficacies are rarely compared. This study aimed to compare efficacy ofa biguanide and a statin in treating PCOS. In a randomized double-blind clinical trial, 400 women with PCOS were recruited within 15 months in Taleghani Hospital. They randomly received either a biguanide (metformin 500 mg three times daily) or a statin (simvastatin 20 mg daily) for three consecutive months. Changes of clinical and laboratory variables were compared. In the biguanide group the serum glucose status (abnormal fasting and non-fasting sugar and insulin levels and percentage of hyperinsulinemic cases) and menstrual abnormalities improved significantly after treatment (p < 0.05). In the statin group the lipid profile status (abnormal total cholesterol, high and low density lipoproteins), C-Reactive Protein (CRP), serum dehydroepiandrosterone sulfate, hyperinsulinemia, severity of acne and menstrual abnormalities improved significantly after treatment (p < 0.05). Comparing the two groups, the improvements in fasting blood sugar and serum insulin levels were significantly better in the biguanide group (p = 0.04 for both parameters); whereas the improvements in serum total cholesterol (p < 0.001), low density lipoprotein (p < 0.001), CRP (p < 0.001) and acne status (p = 0.04) were significantly superior in the statin receivers. Based on these results, each medication is only effective on some aspects of the disease. Overall, the simvastatin was superior to metformin with regard to the number of beneficial effects.     

cDNA-AFLP technique discloses differential gene expression in response to salinity in wheat (Triticum aestivum L.)

Genetic Resources and Crop Evolution - Salinity is one of the well-known abiotic stresses resulting in loss of wheat yield. The identification of differentially induced genes and then becoming...     

Evaluation of apoptosis in long-term culture of vitrified mouse whole ovaries

The purpose of the present study was to investigate the development of follicles and incidence of apoptosis in vitrified neonatal mouse ovaries cultured in vitro in the presence of leukemia inhibitory factor (LIF). The vitrified and non-vitrified ovaries of 1-week-old mouse were cultured in the presence or absence of LIF for 7 days. At the beginning and at the end of culture period in each ovary of all groups of study the mean area and the development of ovarian follicles were analyzed; moreover, the incidence of apoptosis was assessed by transmission electron microscopy, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL) method, DNA laddering and caspase-3/7 activity technique. The hormonal assay was done on the conditioned media collected during culture period. The proportion of preantral follicles and the levels of hormones increased in all cultured groups and it was significantly higher in LIF treated groups than in their control (P < 0.001). The ultrastructural characteristics of cell death, DNA fragmentation and TUNEL positive signals were prominent in vitrified cultured ovaries. The level of caspase-3/7 activity was higher in vitrified cultured ovaries.     

Comparative analysis of genetic diversity using molecular and morphometric markers in Andrographis paniculata (Burm. f.) Nees

Andrographis paniculata is a medicinal plant of immense therapeutic value. The present study was aimed to elucidate its genetic diversity based on morphochemical and RAPD markers from 53 accessions belonging to 5 eco-geographic regions. Analysis of variance and D ² statistics revealed significant differences in all the metric traits and sufficient inter-cluster distances indicating considerable diversity among the accessions. The complementary approach of RAPD was used to evaluate the genetic dissimilarities among all the accessions using 6 highly polymorphic primers. The average proportion of polymorphic loci across primers was 96.28%. The molecular genetic diversity based on Shannon index per primer averaged 5.585 with values ranging from 3.08 to 8.70 indicating towards wide genetic base. RAPD based UPGMA and D ² cluster analysis also revealed that various accessions available in different eco-geographic regions might have originated from native places of wild abundance. Similarity matrices were generated for molecular markers and morphometric data to determine the degree of congruence between the two. A highly significant but low correlation (r = 0.547, P < 0.001) was obtained thus implying the correspondence between the two. The species is hermaphroditic and a habitual inbreeder. The present study yielded a typical triangular congruence between its breeding system, morphometric traits and RAPD markers thus elucidating the usefulness of complementary approaches to make diversity analysis more explanatory and purposeful for optimum genetic amelioration and effective conservation of its genotypic variability.     

The effect of preceding crop on wheat grain zinc concentration and its relationship to total amino acids and dissolved organic carbon in rhizosphere soil solution

The role of cropping systems practices in agronomic biofortification programs with the aim of increasing micronutrient density in food plants has to be clarified. In these field experiments, the effect of four preceding crops, i.e., sunflower (Heliantus annus L. cv. Allstar), Sudan grass (Sorghum bicolor L. cv. Speed Feed), clover (Trifolium pratense L.), and safflower (Carthamus tinctorius L. cv. Koseh-e-Isfahan), on the total amino acids (AA) and dissolved organic carbon (DOC) concentration in rhizosphere soil solution and grain Zn content of successive wheat (Triticum aestivum cvs. Back Cross and Kavir) was investigated during 2009–2010 and 2010–2011 growing seasons. A fallow treatment was also considered as the control. In both growing seasons, preceding crops increased the concentrations of AA and DOC in the soil solution in comparison with the fallow control treatment; although the magnitude of this increase varied upon the preceding crop type and wheat cultivar. In general, clover and sunflower had greater effect on increasing soil solution DOC probably due to higher decomposability of their litter residues in soil. Preceding crops increased the total AA concentration, on average, by 45.9 % for the first year and 10.8 % for the second year. The preceding sorghum and clover had the highest and lowest influence on the concentration of AA in wheat rhizosphere soil solution, respectively. The preceding crops increased grain wheat Zn concentration and content over the fallow control treatment, although this effect was dependent on the crop type. For “Back Cross”, a positive and significant correlation was found between grain Zn concentration and soil solution DOC concentration (r?=?0.60, P?<?0.05) and particularly AA (r?=?0.76, P?<?0.001), while no such correlation was found for “Kavir”. At the second growing season, the concentration of AA in the rhizosphere of Back Cross was greater than that of Kavir, probably due to higher release of these compounds from the roots. According to the results, the preceding crop significantly affect grain Zn density of the successive wheat, that is, at least in part, by releasing soluble organic ligands into soil solution.     

Investigation of TNF-α and IL-6 Levels in the Sera of Non-Melanoma Skin Cancer Patients

Background:TNF-α and IL-6 are both pleiotropic cytokines playing major roles in cancer-associated cytokine networks. They have previously been investigated for their function in skin malignancies, mostly melanomas, and studies on NMSC patients are relatively rare. In this study, we aimed to assess the associations of serum levels of IL-6 and TNF-α with NMSCs and its clinicopathological features. Methods:This cases-control study was carried out to investigate the serum levels of TNF-α and IL-6 in 70 NMSC patients, in comparison with 30 healthy individuals, by means of flow cytometric bead-based immuneoassay. Results:Serum levels of both TNF-α and IL-6 were significantly higher in NMSC patients (6.470 vs. 4.355 pg/ml; p = 0.0468, respectively), compared to healthy individuals (3.205 vs. 0.000 pg/ml; p = 0.0126, respectively). In the subgroup analysis, SCC patients had higher serum levels of IL-6 compared to healthy individuals (3.445 vs. 0.000 pg/ml; p = 0.0432). No other significant differences were observed in the serum levels of these two cytokines among different clinicopathological subgroups of the patients. Conclusion:The increased levels of TNF-α and IL-6 in NMSC patients can be introduced as an epiphenomenon of a complex cancer-induced cytokine cascade. Key Words: Biomarkers, Cytokines, Interleukin-6, Tumor Necrosis Factor-alpha     

Effects of Drying Condition on Physico-chemical Properties of Foam-mat Dried Shrimp Powder

ABSTRACT

The effects of drying parameters on moisture content, water activity, bulk density, water binding capacity (WBC), oil absorption, and color parameters (L*,a*, b*) of foam-mat dried shrimp powders were investigated. Shrimp purees were dried as a foam mat at different drying temperatures (50ºC, 60ºC, and 70ºC) and thicknesses of the foam layer (4 and 8 mm). The experimental results showed that as the temperature increased, the moisture content, water activity, and oil absorption of the samples decreased. However, their solubility increased significantly (P ?0.05). Bulk density of shrimp powder increased with increasing the thickness of the foam layer. Increasing temperature led to increased and decreased WBC with 4 and 8 mm thickness, respectively. Furthermore, the a*, b*, and L* (at 8 mm thickness) decreased with increasing temperature; however, L* increased at 4 mm thickness. Fourier transform infrared (FTIR) spectra showed some major shifts, such as in the region of 1000–1700 cm^?1, related to C–O, C–O–C, and C–H band stretching. The differential scanning calorimetry thermograms showed a large peak with a denaturation peak around 72ºC for shrimp proteins.