Bmp7 functions via a polarity mechanism to promote cloacal septation

Background

During normal development in human and other placental mammals, the embryonic cloacal cavity separates along the axial longitudinal plane to give rise to the urethral system, ventrally, and the rectum, dorsally. Defects in cloacal development are very common and present clinically as a rectourethral fistula in about 1 in 5,000 live human births. Yet, the cellular mechanisms of cloacal septation remain poorly understood.

Methodology/Principal Findings

We previously detected Bone morphogenetic protein 7 (Bmp7) expression in the urorectal mesenchyme (URM), and have shown that loss of Bmp7 function results in the arrest of cloacal septation. Here, we present evidence that cloacal partitioning is driven by Bmp7 signaling in the cloacal endoderm. We performed TUNEL and immunofluorescent analysis on cloacal sections from Bmp7 null and control littermate embryos. We found that loss of Bmp7 results in a dramatic decrease in the endoderm survival and a delay in differentiation. We used immunological methods to show that Bmp7 functions by activating the c-Jun N-terminal kinase (JNK) pathway. We carried out confocal and 3D imaging analysis of mitotic chromosome bundles to show that during normal septation cells in the cloacal endoderm divide predominantly in the apical-basal direction. Loss of Bmp7/JNK signaling results in randomization of mitotic angles in the cloacal endoderm. We also conducted immunohistochemical analysis of human fetal sections to show that BMP/phospho-SMAD and JNK pathways function in the human cloacal region similar as in the mouse.

Conclusion/Significance

Our results strongly indicate that Bmp7/JNK signaling regulates remodeling of the cloacal endoderm resulting in a topological separation of the urinary and digestive systems. Our study points to the importance of Bmp and JNK signaling in cloacal development and rectourethral malformations.     

Cytokines as mediators of neuroimmune interactions

Cytokines regulate numerous physiological and pathological processes in the central nervous system (CNS), i.e. they function both as immune regulators and neuromodulators. Acting upon the CNS via different ways, cytokines, mainly proinflammatory ones IL-1beta and TNF-alpha, can disturb physiological functions of the CNS, cause neurotoxic and neurodegenerative damage and stimulate IL-1beta synthesis in hypothalamus nuclei and posterior pituitary. They can produce stress-like effects upon the CNS and affect the activity of the axis hypothalamus--pituitary--adrenal glands, levels of neuropeptides in hypothalamic regions of brain, synthesis and utilization of central monoamines. These influences can implement the effects of sensitization, which enhances neuroendocrine responses to later stresses. Microglia and astrocytes, secondary messengers and interaction between hypothalamus and anterior pituitary play an important role in range of these processes as well as in the maintenance of Th1/Th2 cytokine balance.     

Inhibition of Ca-induced calcium release from mitochondria by antiischemic phenol-based antioxidants

Effects of different inhibitors of lipid peroxidation (LP), such as sulphur-containing oligoquinone hypoxen, natural flavonoid dihydroquercetin (DHQ), and β-ionol, on Ca²⁺-induced calcium release from rat liver mitochondria (RLM) were investigated during oxidation of various substrates. The hypothesis about interrelation between antioxidant properties and influence of selected substances on spontaneous calcium release from mitochondria was verified. Degree of antioxidant activity of the selected substances was estimated by the inhibition of LP induced by Fe²⁺/ATP complex in phospholipid emulsion or in rat liver mitochondria (RLM). According to the inhibition efficacy the investigated substances were ordered as follows: β-ionol ≫ hypoxen > DHQ. 50% inhibition of oxygen consumption during LP of phospholipid emulsion was reached in presence of 3.2 ± 0.6 μM of β-ionol, 15.0 ± 1.1 μM of hypoxen, or 19.8 ± 1.7 μM of DHQ. Among the investigated antioxidants hypoxen only decreased spontaneous release of calcium from RLM after calcium accumulation by RLM. The impact of the antioxidants onto calcium current depended on the oxidized substrate. Hypoxen effect was most expressed during the oxidation of NAD-dependent substrate. The direct relationship between the antioxidant activity of the selected antioxidants and their influence on calcium transport in RLM was not revealed. The results indicate that the choice of antiischemic preparations should not only rely on their antioxidant activities.     

Trial of a Soviet diagnostic kit for determining class M immunoglobulins to the hepatitis A virus by immunoenzyme analysis (an anti-HAV IgM test system)

The authors have studied the effectiveness of the first Soviet test system for the diagnosis of hepatitis A by means of the enzyme immunoassay (Diagn-A-Hep), developed at the Institute of Poliomyelitis and Viral Encephalitides, Moscow, under the conditions of different epidemic situations. In the process of this trial the high specificity and sensitivity of this test system, established earlier in the certification and commission trials, have been confirmed. Diagn-A-Hep has proved to be highly effective in the diagnosis of acute forms of hepatitis A and permitted its detection in patients during the incubation period, as well as in patients with anicteric and asymptomatic subclinical forms. Besides clinical diagnosis, the kit Diagn-A-Hep may be used in large-scale seroepidemiological surveys of the immune structure of the population, as well as in detection of HAV in different material under test.     

Immunological study of the cellular components of Pseudomonas aeruginosa. VI. The toxicity and protective properties of its mucus and its fractions]

Capsule-like mucus was obtained from two newly isolated mucoid strains of P. aeruginosa and then treated with ethanol. The mucus was fractionated by the method of differential centrifugation (at 15, 000 g for 1 h, at 105, 000 or 170, 000 g for 3 h) and gel chromatography in columns packed with Sepharose 4B. The sediment fractions contained 30--80% of high molecular polysaccharide protein (peptide) mucus components which were toxic for mice and protected 25--77% of rats against experimental P. aeruginosa infection. The supernatant fluid fractions contained 60--80% of predominantly protein components with molecular mass between 20,000 and 60,000 daltons. These mucus components were slightly toxic for mice and rats and protected 80--100% of rats against P. aeruginosa infection.     

Multinuclear blue copper-proteins: the evolutionary design

The review presents both our own and literature data on studies of pathways of evolution of the so-called multinuclear blue copper-proteins (MBCP) that have the domain organization. The MBCP are widely spread in living nature, they have been revealed in cells of archei, bacteria, and eukaryotes. The MBCP composition includes the copper-proteins such different by their properties as oxidases, reductase, blood coagulation factors V and VIII. Most likely, MBCP have been originated from a low-molecular protein-precursor similar topologically with the blue electron-transporting protein of the cupredoxin type, as a result of action of various evolutionary mechanisms: amplification of genes, formation of protein structures by different combinations of domains, a change of size of domains, the segment elongation at the expense of the activational domain, formation and loss of copper-binding centers, variation of amino acid ligands in such centers, the appearance of centers of binding of other proteins, glycosylation, etc.     

Green Synthesis of Genistein-Fortified Zinc Ferrite Nanoparticles as a Potent Hepatic Cancer Inhibitor: Validation through Experimental and Computational Studies

In hepatic cancer, precancerous nodules account for damage and inflammation in liver cells. Studies have proved that phyto-compounds based on biosynthetic metallic nanoparticles display superior action against hepatic tumors. This study targeted the synthesis of genistein-fortified zinc ferrite nanoparticles (GENP) trailed by anticancer activity assessment against diethylnitrosamine and N-acetyl-2-aminofluorene induced hepatic cancer. The process of nucleation was confirmed by UV/VIS spectrophotometry, X-ray beam diffraction, field-emission scanning electron microscopy, and FT-IR. An in vitro antioxidant assay illustrated that the leaves of Pterocarpus mildbraedii have strong tendency as a reductant and, in the nanoformulation synthesis, as a natural capping agent. A MTT assay confirmed that GENP have a strong selective cytotoxic potential against HepG2 cancer cells. In silico studies of genistein exemplified the binding tendency towards human matrix metalloproteinase comparative to the standard drug marimastat. An in vivo anticancer evaluation showed that GENP effectively inhibit the growth of hepatic cancer by interfering with hepatic and non-hepatic biochemical markers.     

Immunologic study of the cellular components of bacillus pyocyaneus. III. Immunochemical analysis, toxicity and protective properties of water-soluble antigenic complexes]

Aqueous extracts of two Ps. aeruginosa strains killed with acetone were subjected to fractionation by preparative ultracentrifugation and gel-chromatography. Toxic activity of the extract was found to be connected with the high-molecular, possibly glycoprotein components reacting with the corresponding antiserum in the immunoprecipitation test, and protecting 30--40% of rats against the generalized infection with Pseudomonas aeruginosa. This protective activity is apparently connected with the protein components (molecular weight--20000--60000 dalton), nontoxic for mice, not reacting with the corresponding antiserum in the immunoprecipitation test, and protecting 60 to 80% of rats against Ps. aeruginosa infecsion. Thus, as a result of preparative ultracentrifugation and gel-chromatography it was postible to divide the toxic and the nontoxic protective components of Ps. aeruginosa.