Interleukin-1β, cyclooxygenase-2, and hypoxia-inducible factor-1α in asthenozoospermia

Impaired male fertility may have a variety of causes, among which asthenozoospermia. In its etiology, several bioactive substances, such as cytokines may be involved. In this context, our aim was to evaluate the expression of interleukin-1β, cyclooxygenase-2, and hypoxia-inducible factor-1α, in spermatozoa isolated from normospermic fertile donors and asthenozoospermic infertile patients. We evaluated twenty-eight infertile patients affected by idiopathic asthenozoospermia and twenty-three normospermic fertile donors, age-matched. Sperm parameters were evaluated; immunohistochemical analysis and enzyme-linked immunosorbent assay were then performed in isolated spermatozoa. Spermatozoa from the asthenozoospermic group presented an increased expression of IL-1β, COX-2, and HIF-1α compared with the normospermic fertile subjects. Our results can lead us to speculate that the increased expression of these substances may influence sperm motility. Nevertheless, further studies are needed in order to assess whether these bioactive mediators have a potential relevance as targets in future therapeutic strategies for the treatment of male infertility.     

Action of phospholipase A2 of rabbit neuronal and glial cells on 1,2-diacyl-, 2-acyl-1-alk-1′-enyl-, and 2-acyl-1-alkyl-glycerophosphatides

Pronounced differences in the phospholipase A₂ activities were found in neurons and glia, the enzyme activity being two- to threefold higher in neurons than in glial cells. Both phospholipases A₂ hydrolyzed the 1,2-diacylglycerophosphatides more rapidly than the acylalkyl and acylalkenyl compounds. Choline plasmalogen and the corresponding alkyl derivative were cleaved at similar rates by the phospholipase A₂ from both glia and neurons. There was a tendency by the neuronal phospholipase A₂ to release arachidonic acid faster than linolenic acid from both phosphatidylcholine and ethanolamine, while arachidonic acid was removed less actively from phosphatidylethanolamine by the glial enzyme. The glial phospholipase A₂ showed a lag period of 10 or 20 min. Norepinephrine, injected into the lateral ventricle of the rabbit brain, stimulated the hydrolysis of the various 1,2-diacyl-, acylalkyl-, and acylalkenyl-glycerophosphatides by the phospholipase A₂ from both glia and neurons.     

Inhibitory Effects of Green Tea and (–)-Epigallocatechin Gallate on Transport by OATP1B1, OATP1B3, OCT1, OCT2, MATE1, MATE2-K and P-Glycoprotein

Green tea catechins inhibit the function of organic anion transporting polypeptides (OATPs) that mediate the uptake of a diverse group of drugs and endogenous compounds into cells. The present study was aimed at investigating the effect of green tea and its most abundant catechin epigallocatechin gallate (EGCG) on the transport activity of several drug transporters expressed in enterocytes, hepatocytes and renal proximal tubular cells such as OATPs, organic cation transporters (OCTs), multidrug and toxin extrusion proteins (MATEs), and P-glycoprotein (P-gp). Uptake of the typical substrates metformin for OCTs and MATEs and bromosulphophthalein (BSP) and atorvastatin for OATPs was measured in the absence and presence of a commercially available green tea and EGCG. Transcellular transport of digoxin, a typical substrate of P-gp, was measured over 4 hours in the absence and presence of green tea or EGCG in Caco-2 cell monolayers. OCT1-, OCT2-, MATE1- and MATE2-K-mediated metformin uptake was significantly reduced in the presence of green tea and EGCG (P < 0.05). BSP net uptake by OATP1B1 and OATP1B3 was inhibited by green tea [IC₅₀ 2.6% (v/v) and 0.39% (v/v), respectively]. Green tea also inhibited OATP1B1- and OATP1B3-mediated atorvastatin net uptake with IC₅₀ values of 1.9% (v/v) and 1.0% (v/v), respectively. Basolateral to apical transport of digoxin was significantly decreased in the presence of green tea and EGCG. These findings indicate that green tea and EGCG inhibit multiple drug transporters in vitro. Further studies are necessary to investigate the effects of green tea on prototoypical substrates of these transporters in humans, in particular on substrates of hepatic uptake transporters (e.g. statins) as well as on P-glycoprotein substrates.     

Mutators in SACCHAROMYCES CEREVISIAE: MUT1–1, MUT1–2 and MUT2–1

The purpose of this study was to characterize two mutator stocks of yeast which were induced and selected on the basis of high spontaneous reversion rates of the suppressible "ochre" nonsense allele lys1-1. In the mutator stock VA-3, a single mutation, designated mut1-1, is responsible for the increase in the reversion rate of the ochre alleles lys1-1 and arg4-17. In stock VA-105, there are two separate mutator mutations. Tetrad analysis data showed these two loci are loosely linked. Based on complementation data, one of these mutations is at the same locus as mut1-1 and designated mut1-2. The second mutator of stock VA-105 was designated mut2-1. All three mutators are recessive. Both mut1-1 and mut1-2 give a high mutation rate for ochre nonsense suppressor (SUP) loci, but not for the ochre nonsense alleles. On the contrary, the mutation rates of the ochre alleles are greatly reduced. With the mutant mut2-1 there were mutations at both the lys1-1 site and its suppressors; mut2-1 is as effective as mut1-2 but not as effective as mut1-1 in inducing reversions of a missense mutant, his1-7. Neither mut1-1, mut1-2 nor mut2-1 were effective in inducing reversions of a putative frameshift mutation, hom3-10, or in inducing forward mutations to canavanine resistance.     

Substrate specificity of protein tyrosine phosphatases 1B, RPTPα, SHP-1, and SHP-2

We determined the substrate specificities of the protein tyrosine phosphatases (PTPs) PTP1B, RPTPα, SHP-1, and SHP-2 by on-bead screening of combinatorial peptide libraries and solution-phase kinetic analysis of individually synthesized phosphotyrosyl (pY) peptides. These PTPs exhibit different levels of sequence specificity and catalytic efficiency. The catalytic domain of RPTPα has very weak sequence specificity and is approximately 2 orders of magnitude less active than the other three PTPs. The PTP1B catalytic domain has modest preference for acidic residues on both sides of pY, is highly active toward multiply phosphorylated peptides, but disfavors basic residues at any position, a Gly at the pY-1 position, or a Pro at the pY+1 position. By contrast, SHP-1 and SHP-2 share similar but much narrower substrate specificities, with a strong preference for acidic and aromatic hydrophobic amino acids on both sides of the pY residue. An efficient SHP-1/2 substrate generally contains two or more acidic residues on the N-terminal side and one or more acidic residues on the C-terminal side of pY but no basic residues. Subtle differences exist between SHP-1 and SHP-2 in that SHP-1 has a stronger preference for acidic residues at the pY-1 and pY+1 positions and the two SHPs prefer acidic residues at different positions N-terminal to pY. A survey of the known protein substrates of PTP1B, SHP-1, and SHP-2 shows an excellent agreement between the in vivo dephosphorylation pattern and the in vitro specificity profiles derived from library screening. These results suggest that different PTPs have distinct sequence specificity profiles and the intrinsic activity/specificity of the PTP domain is an important determinant of the enzyme's in vivo substrate specificity.     

Genetic association of IDE,POU2F1, PON1, IL1α and IL1β with type 2 diabetes in Pakistani population

A number of genes are known to be involved in glucose homeostasis. Mutations and polymorphisms in candidate genes may effect insulin production, action or resistance. This study was designed to report the association of genetic polymorphism with the type 2 diabetes (T2D) in Pakistani population. A total of 458 subjects (case n = 288, control n = 170) participated in the study. Nine single nucleotide polymorphisms were investigated in genes IDE (rs6583813 C>T, rs7910977 C>T), POU2F1 (rs3767434 A>T, rs10918682 A>T, rs2146727 A>G), WFS1 (rs734312 A>G), PON1 (rs854560 T>A), IL1α (rs1800587 C>T) and IL1β (rs1143634 C>T). Genotyping was performed by DNA sequencing after nested polymerase chain reaction of targeted regions. Results indicated that rs7910977 in IDE showed significant association with the development of T2D [P = 0.012, OR 1.677 (95 % CI 1.112–2.438)]. The rs10918682 in POU2F1 was associated with T2D [P < 0.001, OR 3.606 (95 % CI 2.165–6.005)]. The rs854560 in PON1was associated with incidences of T2D and increased the risk of cardiovascular complications [P = 0.031, OR 0.663 (95 % CI 0.455–0.965)] in diabetics. The rs734312 from WFS1 gene was associated with diabetes at genotype level (P < 0.01). Haplotype analysis of rs1800587–rs1143634 depicted CC haplotype increased the susceptibility to diabetes (P < 0.05). Haplotype GAA from rs2146727–10918682–rs3767434 was protective against diabetes (P < 0.01) and GGA exhibited the association with T2D (P < 0.01). Haplotype CT from rs6583813–rs7910977 was protective against diabetes (P = 0.02). Our study provided evidence to IDE, PON1, WFS1, POU2F1, IL1α and IL1β associated with T2D in Pakistanis.     

潘庆民1,于振文2,王月福2

采用盆栽和水泥池栽研究了追氮时期对小麦光合作用、14C同化物运转分配和硝酸还原酶(NR)活性的影响.结果表明,拔节(雌雄蕊原基形成)期较起身(二棱)期追施氮肥,显著提高了小麦开花后的旗叶叶绿素含量和单叶光合速率;灌浆期旗叶14C同化物向籽粒转移比例显著提高,而在营养器官的滞留比例显著降低;旗叶和根系中硝酸还原酶(NR)活性亦显著提高.小麦穗粒数、粒重和产量增加,蛋白质含量提高.     

Synthesis and Properties of P1, P2-, P1, P3- and P1, P4-Dinucleoside Di-, Tri- and Tetraphosphate mRNA 5′-Cap Analogues

Abstract

Chemically synthesized dinucleoside P¹, P²-di-, P¹, P³-tri- and P¹, P⁴-tetraphosphates, derivatives of 5′-linked 7-methylguanosine and guanosine were characterized with respect to their structural properties and functional effect on eukaryotic translation inhibition.     

Soluble guanylate cyclase isoenzymes: The expression of α1, α2, β1, and β2 subunits in the benign and malignant breast tumors

Soluble guanylate cyclase (sGC) encompasses α and β subunits. This study examined the expression of α1, α2, β1, and β2 subunits in the malignant and benign breast tumors using the Western blot analysis. Both benign and malignant tumors showed a significantly higher expression of the α1 subunit in comparison with normal tissues (p < 0.0001). In contrast, the expression of α2 and β2 sGC were significantly lower in these tumors than normal tissues (p < .0015 and p < .001, p < .007 and p < .0001, respectively). The expression level of α1 sGC was significantly correlated with ER + PR+ (p < .0001). A significant correlation was also detected for sGC-α1 and -α2 expression with c-erbB2-negative status (p < .01). However, the expression level of sGC was not associated with tumor stage, tumor grade, or other clinicopathological features. In conclusion, as the expression of α1 sGC is upregulated and α2 and β2 sGC are downregulated in malignant breast tumors. Variations in the expression of sGC isoenzymes may be suggested as an indicator to confirm the enzyme antitumor activity.     

Direct actions of prostaglandins E1, A1, and F2α on myocardial contraction

The inotropic and chronotropic actions of prostaglandin (PG) types PGE₁, PGA₁, and PGF_2α were studied in isolated guinea pig right and left atria, and papillary muscles; rabbit atria; and toad ventricular strips in order to more completely define the cardiac contractile properties of PG. All three prostaglandins, in muscle bath concentrations of 10μg/ml, exerted positive inotropic and chronotropic actions on guinea pig atrium. These contractile effects were persistent after removal of PG from the muscle bath and appeared to limit the relative response to a subsequent dose of PG. The inotropic action of PGE₁ was present over a wide range of bath calcium concentrations (1.1 to 4.4 mM/L). Beta adrenergic receptor blockade, histamine blockade, and pretreatment with reserpine failed to significantly affect the inotropic actions of PG. Norepinephrine and histamine produced more potent inotropic and chronotropic effects on guinea pig atria than did PG and these contractile effects did not exhibit persistence or tachyphylaxis. The prostaglandins did not significantly affect dose response curves for norepinephrine inotropic and chronotropic actions. The prostaglandins had no effect on the force or frequency of contraction in rabbit atria. PGE₁ exerted a positive inotropic effect on toad ventricular myocardium whereas PGA₁ had no effect and PGF_2α had a negative inotropic action.     

Carvedilol Decrease IL-1β and TNF-α, Inhibits MMP-2, MMP-9, COX-2, and RANKL Expression,and Up-Regulates OPG in a Rat Model of Periodontitis

Periodontal diseases are initiated primarily by Gram-negative, tooth-associated microbial biofilms that elicit a host response that causes osseous and soft tissue destruction. Carvedilol is a β-blocker used as a multifunctional neurohormonal antagonist that has been shown to act not only as an anti-oxidant but also as an anti-inflammatory drug. This study evaluated whether Carvedilol exerted a protective role against ligature-induced periodontitis in a rat model and defined how Carvedilol affected metalloproteinases and RANKL/RANK/OPG expression in the context of bone remodeling. Rats were randomly divided into 5 groups (n = 10/group): (1) non-ligated (NL), (2) ligature-only (LO), and (3) ligature plus Carvedilol (1, 5 or 10 mg/kg daily for 10 days). Periodontal tissue was analyzed for histopathlogy and using immunohistochemical analysis characterized the expression profiles of MMP-2, MMP-9, COX-2, and RANKL/RANK/OPG and determined the presence of IL-1β, IL-10 and TNF-α, myeloperoxidase (MPO), malonaldehyde (MDA) and, glutathione (GSH). MPO activity in the group with periodontal disease was significantly increased compared to the control group (p<0.05). Rats treated with 10 mg/kg Carvedilol presented with significantly reduced MPO and MDA concentrations (p<0.05) in addition to presenting with reduced levels of the pro-inflammatory cytokines IL-1 β and TNF-α (p<0.05). IL-10 levels in Carvedilol-treated rats remained unaltered. Immunohistochemical analysis demonstrated reduced expression of MMP-2, MMP-9, RANK, RANKL, COX-2, and OPG in rats treated with 10 mg/kg Carvedilol. This study demonstrated that Carvedilol affected bone formation/destruction and anti-inflammatory activity in a rat model of periodontitis.     

Separation, purification, and sequence identification of TGF-β1 and TGF-β2 from bovine milk

Cox and Bürk (Eur. J. Biochem., 1991) reported the partial characterization of Milk Growth Factor (MGF) which stimulated the migration of fibroblasts. We have fractionated the partially purified sample by RP-HPLC and obtained the separation of two peaks of activity. The two active components were isolated as pure MGF-a and MGF-b by RP-HPLC and preparative SDS-PAGE. The purified MGF-a, consisting of a single band by gel electrophoresis and a single peak on an HPLC reversed-phase C-4 column, has the same specific activity as TGF-2 in the fibroblast migration assay. MGF-a was digested by endoprotease Asp-N and the cleaved peptides were analyzed by Edman degradation and plasma desorption mass spectrometry (PDMS). The whole sequence of MGF-a determined by automated sequenator and PDMS of S-pyridylethylated protein and selected fragments was found to be identical to that of TGF-2. MGF-b protein mixture separated by SDS-PAGE was electrophoretically transferred onto a Biometra Glassybond membrane, and the blotted MGF-b protein was directly sequenced on an automated sequenator. The identified 29 amino acids sequence of MGF-b was identical to the amino-terminal sequence of TGF-1. Our study demonstrates that MGF is composed of both TGF-1 and TGF-2. TGF-2 (85%) is the predominant form.     

cPLA2α and EHD1 interact and regulate the vesiculation of cholesterol-rich, GPI-anchored, protein-containing endosomes

The lipid modifier phospholipase A2 catalyzes the hydrolysis of phospholipids to inverted-cone-shaped lysophospholipids that contribute to membrane curvature and/or tubulation. Conflicting findings exist regarding the function of cytosolic phospholipase A2 (cPLA2) and its role in membrane regulation at the Golgi and early endosomes. However, no studies addressed the role of cPLA2 in the regulation of cholesterol-rich membranes that contain glycosylphosphatidylinositol-anchored proteins (GPI-APs). Our studies support a role for cPLA2α in the vesiculation of GPI-AP-containing membranes, using endogenous CD59 as a model for GPI-APs. On cPLA2α depletion, CD59-containing endosomes became hypertubular. Moreover, accumulation of lysophospholipids induced by a lysophospholipid acyltransferase inhibitor extensively vesiculated CD59-containing endosomes. However, overexpression of cPLA2α did not increase the endosomal vesiculation, implying a requirement for additional factors. Indeed, depletion of the "pinchase" EHD1, a C-terminal Eps15 homology domain (EHD) ATPase, also induced hypertubulation of CD59-containing endosomes. Furthermore, EHD1 and cPLA2α demonstrated in situ proximity (<40 nm) and interacted in vivo. The results presented here provide evidence that the lipid modifier cPLA2α and EHD1 are involved in the vesiculation of CD59-containing endosomes. We speculate that cPLA2α induces membrane curvature and allows EHD1, possibly in the context of a complex, to sever the curved membranes into vesicles.     

Functional elements in initiation factors 1, 1A, and 2β discriminate against poor AUG context and non-AUG start codons

Yeast eIF1 inhibits initiation at non-AUG triplets, but it was unknown whether it also discriminates against AUGs in suboptimal context. As in other eukaryotes, the yeast gene encoding eIF1 (SUI1) contains an AUG in poor context, which could underlie translational autoregulation. Previously, eIF1 mutations were identified that increase initiation at UUG codons (Sui(-) phenotype), and we obtained mutations with the opposite phenotype of suppressing UUG initiation (Ssu(-) phenotype). Remarkably, Sui(-) mutations in eukaryotic translation initiation factor 1 (eIF1), eIF1A, and eIF2β all increase SUI1 expression in a manner diminished by introducing the optimal context at the SUI1 AUG, whereas Ssu(-) mutations in eIF1 and eIF1A decrease SUI1 expression with the native, but not optimal, context present. Therefore, discrimination against weak context depends on specific residues in eIFs 1, 1A, and 2β that also impede selection of non-AUGs, suggesting that context nucleotides and AUG act coordinately to stabilize the preinitiation complex. Although eIF1 autoregulates by discriminating against poor context in yeast and mammals, this mechanism does not prevent eIF1 overproduction in yeast, accounting for the hyperaccuracy phenotype afforded by SUI1 overexpression.     

Olmesartan Decreased Levels of IL-1β and TNF-α, Down-Regulated MMP-2, MMP-9, COX-2, RANK/RANKL and Up-Regulated SOCs-1 in an Intestinal Mucositis Model

Methotrexate (MTX) is a pro-oxidant compound that depletes dihydrofolate pools and is widely used in the treatment of leukaemia and other malignancies. The efficacy of methotrexate is often limited by mucositis and intestinal injury, which are major causes of morbidity in children and adults. The aim of this study was to evaluate the effect of olmesartan (OLM), an angiotensin II receptor antagonist, on an Intestinal Mucositis Model (IMM) induced by MTX in Wistar rats. IMM was induced via intraperitoneal (i.p.) administration of MTX (7 mg/kg) for three consecutive days. The animals were pre-treated with oral OLM at 0.5, 1 or 5 mg/kg or with vehicle 30 min prior to exposure to MTX. Small intestinal homogenates were assayed for levels of the IL-1β, IL-10 and TNF-α cytokines, malondialdehyde and myeloperoxidase activity. Additionally, immunohistochemical analyses of MMP-2, MMP-9, COX-2, RANK/RANKL and SOCS-1 and confocal microscopy analysis of SOCS-1 expression were performed. Treatment with MTX + OLM (5 mg/kg) resulted in a reduction of mucosal inflammatory infiltration, ulcerations, vasodilatation and haemorrhagic areas (p<0.05) as well as reduced concentrations of MPO (p<0.001) and the pro-inflammatory cytokines IL-1β (p<0.001) and TNF-a (p<0.01), and increase anti-inflammatory cytocine IL-10 (p<0.05). Additionally, the combined treatment reduced expression of MMP-2, MMP-9, COX-2, RANK and RANKL(p<0.05) and increased cytoplasmic expression of SOCS-1 (p<0.05). Our findings confirm the involvement of OLM in reducing the inflammatory response through increased immunosuppressive signalling in an IMM. We also suggest that the beneficial effect of olmesartan treatment is specifically exerted during the damage through blocking inflammatory cytocines.     

Morphological characteristics and chromosome behaviour in F1, F2 and BC1 progenies between Chrysanthemum × morifolium and Ajania pacifica

The garden chrysanthemum (Chrysanthemum × morifolium) variety ??Aoyunhuoju?? (2n = 6x = 54) was crossed as female with Ajania pacifica (2n = 10x = 90) to produce intergeneric F1 hybrids, which were used both as the source of F₂ generation and as the parent for a first back-cross with ??Aoyunhuoju??. The morphology of all of the F₁ hybrids and hybrid derivatives was intermediate with respect to the two parents, although the BC₁ progenies resembled ??Aoyunhuoju?? more closely than any of the F₁ and F₂ progenies did. In the F₁ generation, the density of silvery hairs on the lower leaf surface and along the margin of the leaf was lower than in A. pacifica, while that in the BC1 generation, this trait was less prominent than in the F₁. The somatic chromosome number of the F₁, F₂ (with an exception of F₂-6 of a mainly 63) and BC1 generations was 2n = 8x = 72, 2n = 8x = 72 and 2n = 7x = 63 respectively, as expected. The hybrids and their derivatives retained a variable degree of fertility. There was a low frequency of meiotic chromosome pairing failure in all three hybrid generations, with most of the chromosomes involved as bivalents. Some BC₁ individuals show potential for commercialization thanks both to their flower shape and the inheritance of the silvery leaf trait from A. pacifica.