Long-term chromium picolinate supplementation improves colostrum profile of Santa Ines ewe

Biological Trace Element Research - Chromium (Cr) is a micromineral that is involved in the metabolism of carbohydrates, lipids, ammonia, and nucleic acids; thus, its supplementation can influence...     

IgG absorption by Santa Ines lambs fed Holstein bovine colostrum or Santa Ines ovine colostrum

The objective of this study was to evaluate the immunoglobulin G (IgG) absorption by Santa Ines lambs under two colostrum management systems usually used by producers. Twenty-seven Santa Ines newborn lambs received two meals of 250 ml of bovine colostrum from Holstein cows (BC group) or ovine colostrum from Santa Ines ewes (OC group) at 0 and 6 h of life. Pools of BC and OC were analyzed by radial immunodiffusion to quantify IgG. Results are expressed as least-square means and standard errors of mean (means ± s.e.m.). The concentration of IgG in bovine and ovine pools averaged 115.7 ± 20.5 and 48.1 ± 5.0 mg/ml, respectively, levels of concentration found in similar regular colostrum managements. The efficiency of IgG absorption was evaluated under two aspects, maximum apparent efficiency of absorption and total apparent efficiency of absorption (AEAmax and AEAtotal, respectively). The AEAmax was calculated taking into account the mass of IgG ingested just in the first meal of colostrum at birth and the serum IgG concentration at 6 h while the AEAtotal took into account the serum IgG concentration at 24 h of life that reflects the first colostrum offered at birth and the second meal at 6 h. The IgG and apparent efficiency of absorption results were transformed into the square root and log base 10, respectively, and were presented as geometric least-square means. In BC, lower (P < 0.05) AEAmax and AEAtotal were verified (14.2% and 15.6%, respectively), in relation to OC (23.6% and 24.4%, respectively). Serum IgG concentrations at 24 h were significantly higher (P < 0.05) in BC (31.4 mg/ml, respectively) compared with OC (22.2 mg/ml, respectively). The results in this study confirm that there is a limitation to the process of IgG absorption by the enterocytes of newborn lambs, which determined a nonlinear behavior of passive immunity acquisition. Similar values of AEAmax and AEAtotal for the two sources of colostrum reveal that the process of IgG absorption from the first and second meals during the first 6 h of life did not change and indicates that the ingestion of a second feeding of quality colostrum can enhance the acquisition of immune protection of newborn lambs.     

ARHGAP21 is a RhoGAP for RhoA and RhoC with a role in proliferation and migration of prostate adenocarcinoma cells

Background: Several Rho GTPase-activating proteins (RhoGAPs) are implicated in tumor progression through their effects on Rho GTPase activity. ARHGAP21 is a RhoGAP with increased expression in head and neck squamous cell carcinoma and with a possible role in glioblastoma tumor progression, yet little is known about the function of ARHGAP21 in cancer cells. Here we studied the role of ARHGAP21 in two prostate adenocarcinoma cell lines, LNCaP and PC3, which respectively represent initial and advanced stages of prostate carcinogenesis. Results: ARHGAP21 is located in the nucleus and cytoplasm of both cell lines and its depletion resulted in decreased proliferation and increased migration of PC3 cells but not LNCaP cells. In PC3 cells, ARHGAP21 presented GAP activity for RhoA and RhoC and induced changes in cell morphology. Moreover, its silencing altered the expression of genes involved in cell proliferation and cytoskeleton organization, as well as the endothelin-1 canonical pathway. Conclusions: Our results reveal new functions and signaling pathways regulated by ARHGAP21, and indicate that it could contribute to prostate cancer progression.     

Stathmin 1 in normal and malignant hematopoiesis

Stathmin 1 is a microtubule destabilizer that plays an important role in cell cycle progression, segregation of chromosomes, clonogenicity, cell motility and survival. Stathmin 1 overexpression has been reported in malignant hematopoietic cells and Stathmin 1 inhibition reduces the highly proliferative potential of leukemia cell lines. However, during the differentiation of primary hematopoietic cells, Stathmin 1 expression decreases in parallel to decreases in the proliferative potential of early hematopoietic progenitors. The scope of the present review is to survey the current knowledge and highlight future perspectives for Stathmin 1 in normal and malignant hematopoiesis, with regard to the expression, function and clinical implications of this protein. [BMB Reports 2014; 47(12): 660-665]     

ANKHD1, a novel component of the Hippo signaling pathway,promotes YAP1 activation and cell cycle progression in prostate cancer cells

ANKHD1 is a multiple ankyrin repeat containing protein, recently identified as a novel member of the Hippo signaling pathway. The present study aimed to investigate the role of ANKHD1 in DU145 and LNCaP prostate cancer cells. ANKHD1 and YAP1 were found to be highly expressed in prostate cancer cells, and ANKHD1 silencing decreased cell growth, delayed cell cycle progression at the S phase, and reduced tumor xenograft growth. Moreover, ANKHD1 knockdown downregulated YAP1 expression and activation, and reduced the expression of CCNA2, a YAP1 target gene. These findings indicate that ANKHD1 is a positive regulator of YAP1 and promotes cell growth and cell cycle progression through Cyclin A upregulation.     

Improved assessment of viability and germination of Cattleya (Orchidaceae) seeds following storage

Effective seed storage methods for orchid species provide a unique opportunity to preserve large amounts of germplasm. Early evaluation of the physiological status of seeds is useful for selecting seed lots for conservation. To score seed quality, seeds from nine Cattleya species (Cattleya granulosa, Cattleya hegeriana, Cattleya intermedia, Cattleya mossiae, Cattleya purpurata, Cattleya sanguiloba, Cattleya tenuis, Cattleya tigrina and Cattleya walkeriana) were germinated on Knudson C medium and viability was measured using a tetrazolium (TZ) test following pre-conditioning in a 10% sucrose solution, both before and after storage at −18°C for 3 mo. Tetrazolium test results were quantified using digital imaging of germinating seeds on a flatbed scanner. Seed viability (with or without pre-conditioning in sucrose), germination, Germination Velocity Index (GVI) and the correlation between viability measurements and germination were also evaluated. Both the tetrazolium test and the germination results showed that there was no loss of viability after storage, although in five seed lots, the GVI decreased. Pre-conditioning improved the correlation between viability exhibited in the tetrazolium test and seed germination. Image analysis proved to be a powerful tool for analysing these small seeds.     

Acute lethal and sublethal effects of neem leaf extract on the neotropical freshwater fish Prochilodus lineatus

The aim of this study was to determine the toxicity of the aqueous extract of neem leaves, a product extensively used in fish-farms as alternative for the control of fish parasites and fish fry predators, for the neotropical fish Prochilodus lineatus. The 24 h LC(50) of neem leaf extract for juveniles P. lineatus was estimated as 4.8 g L(-1); the fish were then exposed for 24 h to 2.5, 5.0 and 7.5 g L(-1) or only clean water (control). Plasma glucose levels were higher in fish exposed to 2.5 g L(-1) and 5.0 g L(-1) neem extract, relative to control, indicating a typical stress response. Neem extract did not interfere with the osmoregulating capacity of the fish, as their plasma sodium, chloride, total protein and osmolarity did not change. The presence of the biopesticide interfered with the antioxidant defense system of P. lineatus, as there was a decrease in liver catalase activity at all neem concentrations and the detoxifying enzyme glutathione-S-transferase was activated in fish exposed to 5.0 g L(-1). Fish exposed to all neem extract concentrations exhibited damaged gill and kidney tissue. These results indicate that although neem extract is less toxic to P. lineatus than other synthetic insecticides used in fish-farming it does cause functional and morphological changes in this fish species.     

PIPKIIα is widely expressed in hematopoietic-derived cells and may play a role in the expression of alpha- and gamma-globins in K562 cells

Characterized for the first time in erythrocytes, phosphatidylinositol phosphate kinases (PIP kinases) belong to a family of enzymes that generate various lipid messengers and participate in several cellular processes, including gene expression regulation. Recently, the PIPKIIα gene was found to be differentially expressed in reticulocytes from two siblings with hemoglobin H disease, suggesting a possible relationship between PIPKIIα and the production of globins. Here, we investigated PIPKIIα gene and protein expression and protein localization in hematopoietic-derived cells during their differentiation, and the effects of PIPKIIα silencing on K562 cells. PIPKIIα silencing resulted in an increase in α and γ globins and a decrease in the proliferation of K562 cells without affecting cell cycle progression and apoptosis. In conclusion, using a cell line model, we showed that PIPKIIα is widely expressed in hematopoietic-derived cells, is localized in their cytoplasm and nucleus, and is upregulated during erythroid differentiation. We also showed that PIPKIIα silencing can induce α and γ globin expression and decrease cell proliferation in K562 cells.