The analgesic and anti-inflammatory effects of shark cartilage are due to a peptide molecule and are nitric oxide (NO) system dependent

The present work shows an antinociceptive and dose-dependent effect of shark cartilage hydrosoluble fraction (HF) on writhing and formalin tests in mice. The effect was not altered by thalidomide, a known inhibitor of tumor necrosis factor-alfa (TNF-alfa) synthesis. Similarly, the antinociceptive effect did not change in the presence of naloxone, indicating that the opioid system is not involved. However, the effect observed was blocked by L-arginine, a NO synthesis substrate, and it was potentiated by L-NAME, suggesting a role of the NO system in the shark cartilage antinociceptive effect. Effects similar to those seen with the HF were detected with peak II from gel filtration chromatography. The increase in vascular permeability induced by serotonin in rats was significantly abolished by the HF at the dose of 2 mg/kg, p.o., and again it was not potentiated by thalidomide. The observed blockade in the vascular permeability increase induced by histamine was detected only with a higher dose (10 mg/kg, p.o.).

Ca2+ sparks within 200 nm of the sarcolemma of rat ventricular cells: evidence from total internal reflection fluorescence microscopy

Total internal reflection fluorescence microscopy (TIRFM) was used to measure local calcium releases in resting cardiac myocytes stained with fluo-3AM. The measured fluorescence originated from regions where cells were close to, and develop adhesions to, a totally reflecting glass surface. The excitation of the fluorescent Ca2+ indicator dye by the exponentially attenuated evanescent wave penetrated approximately 200 nm into the fluid phase. In rat ventricular cells, Ca2+ waves and Ca2+ sparks were observed within the adhesions. Ca2+ sparks recorded with TIRFM compared favorably to sparks recorded under similar conditions with confocal microscopy. Computer simulation supported this assessment. It is concluded that TIRFM can provide an economical, flexible tool for detailed measurement of Ca(2+)-transients in the subsarcolemmal space of live cells.

["Lingue di seripi", "serpents' tongues" and "glossopetrae". Highlights from the history of popular "cult" medicine in early modern times]

In the 16th, 17th and 18th century "Glossopetrae", popularly known as "Lingue di Serpi", found on the Mediterranean island of Malta, were extensively used for medical purposes as antidotes. These fossil teeth, including specimens of the "Carcharodon Megalodon" (an extinct variant of the great white shark), were ground to powder or used as amulet pendants and "credence" and exported to pharmacies and shops in various cities of Europe. In antiquity, authors like Plinius or Solinus, excluding any religious connotations, had regarded "Glossopetrae" as objects "fallen from heaven on dark moonless nights". However, from the beginning of the 16th century the miraculous antidotic power of the specimens found at Malta was very strongly connected with the Pauline cult there. This cult owed ist origin to the excerpt of the shipwreck of the Apostle of the Gentiles on this island, as recorded in the New Testament. As in so many cases found in medieval and early modern medicine and pharmacy, the renown, collection, distribution and use of the antidote "Glossopetrae" or "Lingue di Serpi" was never limited to its real chemical and pharmaceutical properties. In the period of enlightenment and secular thinking mythic medicine as "Glossopetrae" had lost ist "magical" power. Consequently, with beginning of the late 18th century also the Maltese "Glossopetrae" featured in literature merely as exotic objects of curiosity or symbols of an age bound to medical superstition.

Amino acid sequence, binding properties and evolutionary relationships of the basic liver fatty-acid-binding protein from the catfish Rhamdia sapo

The complete amino acid sequence of a basic liver fatty acid-binding protein (L-FABP) from catfish (Rhamdia sapo) was determined. Alignment of sequences shows that it has more similarity to chicken basic L-FABP than to mammalian L-FABP. The phylogenetic analysis suggests that basic L-FABP from catfish, chicken and iguana diverged from the mammalian protein before the fish-tetrapod divergence, thus implying that the two types are encoded by different genes. Supporting this conclusion, a 14-kDa protein, structurally closely related to mammalian L-FABP, was isolated from catfish intestine, indicating the presence of the two genes in the same species. The catfish basic L-FABP binds only one fatty acid/molecule, while mammalian L-FABP bind two. The former has more affinity for trans-parinaric acid than for cis-parinaric acid, in constrast to the latter proteins.

Characterization of the secondary structure and assembly of the transmembrane domains of trypsinized Na,K-ATPase by Fourier transform infrared spectroscopy

Fourier transform infrared spectroscopy has been used to compare native Na,K-ATPase-containing membranes with those trypsinized in the presence of either Rb+ or Na+ ions to remove the extramembranous parts of the protein. The protein secondary structure content deduced from the amide I band is approximately 30-35% alpha-helix, 37-40% beta-structure, and 13-15% random coil for native membranes from shark rectal gland and from pig kidney, in both the Na- and K-forms. Trypsinization in either Rb+ (a K+ congener) or Na+ removes approximately 35% of the amide I band intensity of native membranes from shark rectal gland. The protein secondary structural content of the trypsinized membranes lies in the range of approximately 23-32% alpha-helix, 37-46% beta-structure, and 12-18% random coil for the shark and kidney enzymes. The distribution of intensity between the bands corresponding to protonated and deuterium-exchanged alpha-helices, and between the component bands attributed to beta-structure, changes considerably on trypsinization, in the direction of a greater proportion of protonated alpha-helix and a broader range of frequencies for beta-structure. The kinetics of deuteration of the slowly exchanging population of protein amide groups is also changed on trypsinization. The mean rate constant for deuteration of trypsinized membranes is approximately half that for native membranes, whereas the proportion of amides contributing to this population increases on trypsinization. The temperature dependence of the amide I band in the Fourier transform infrared spectra indicates that the onset of thermal denaturation occurs at 58 degrees C for native membranes (in either Na+ or K+) and for membranes trypsinized in Rb+, but the major denaturation event for membranes trypsinized in Na+ occurs at approximately 84 degrees C. These results correlate with the functional properties of the intramembranous section of the enzyme.

A comparison of the hydroxyl radical scavenging properties of the shark bile steroid 5 beta-scymnol and plant pycnogenols

The hydroxyl radical (OH.) quenching abilities of the following compounds were compared in the deoxyribose degradation system (initiated by the ferrous-ascorbate Fenton reaction): (a) 5 beta-scymnol, the hepatoprotective shark bile sterol, and its mono- and di-sulfate esters; (b) three marketed pycnogenol preparations (syn: proanthocyanidin--natural plant-derived polyphenolic bioflavonoids) extracted from pine tree (Pinus maritima) bark and grape (Vitis vinifera) seeds; and (c) two known hydroxyl radical scavengers, dimethyl sulfoxide and mannitol, and the peroxyl radical scavenger Trolox (the alpha-tocopherol analogue). 5 beta-scymnol was a more potent OH. quencher than dimethyl sulfoxide, mannitol and Trolox, and markedly more potent than the pycnogenol preparations. Increased sulfation of 5 beta-scymnol progressively reduced its free radical scavenging activity, thus clearly attributing the potent OH. quenching properties to its novel tri-alcohol-substituted aliphatic side chain. The favourable interaction of these bile steroids with reactive oxygen species in an aqueous environment, makes them attractive candidates for evaluation as protective agents against disorders in which oxidative stress is implicated.

Vibrio damsela associated with diseased fish in Denmark

A total of 26 Vibrio damsela strains were isolated in Denmark. Fifteen strains were isolated from the head kidney of rainbow trout (Oncorhynchus mykiss) in aquaculture, eight were from organs of two stingrays (Dasyatis pastinaca) held in captivity, two were from organs and pathological material of a nurse shark (Orectolobus ornatus) held in captivity, and one was from the water in the aquarium where the rays and shark were kept. This is the first report on the isolation of V. damsela in Denmark and the first report on this organism associated with diseased farmed rainbow trout. Ecological and epizootiological aspects of the observation are discussed on the basis of phenotypic and genotypic properties of the isolated strains.

Inhibition of human leukocyte elastase activity by chondroitin sulfates

Chondroitin sulfates with different properties and devoid of appreciable anticoagulant activity were evaluated for their capacity to inhibit human leukocyte elastase activity in vitro by using a chromogenic substrate. Fractions with various mass and the same charge density were tested. The chondroitin sulfates with a molecular mass greater than about 2000 inhibited human leukocyte elastase activity to the same extent, whilst the fractions with a molecular mass of 1960 and 1020 were much less effective. The percentage inhibition of human leukocyte elastase activity increased based on the charge density of chondroitin sulfates. In particular, the inhibition of the enzymatic activity decreased with the percentage of non-sulfated disaccharide and increased with the amount of disaccharide-2,6-disulfated.

Characterization of Cu,Zn superoxide dismutase from the bathophile fish, Lampanyctus crocodilus

Cu,Zn SOD from the bathophile teleost Lampanyctus crocodilus (LSOD) shows a high degree of homology with the sequence of the enzymes from other teleostean fish species. The catalytic properties of LSOD are very similar to those of the bovine enzyme, albeit with higher sensitivity to thermal denaturation. The apparent molecular mass of LSOD (37.6 KDa) is higher than the other Cu,Zn SOD variants studied. The aminoacid sequence of LSOD reveals interesting substitutions compared to the bovine enzyme. These are discussed in view of the particular environmental conditions to which L. crocodilus is adapted.

Characteristics of renal Na(+)-D-glucose cotransport in the skate (Raja erinacea) and shark (Squalus acanthias)

We have investigated the properties of the skate (Raja erinacea) and shark (Squalus acanthias) kidney Na(+)-D-glucose cotransporters (SGLT) in uptake studies of radiolabeled substrates into isolated renal brush-border membrane vesicles (BBMV). Scatchard plot analysis of the substrate dependence revealed that the Na(+)-D-glucose cotransporter population is homogenous within each species. Skate BBMV showed a relatively high affinity for D-glucose [Michaelis constant (K(m)) = 0.12 mM] with an apparent coupling ratio of approximately 2 Na+ to 1 D-glucose, whereas the shark transporter was much lower in affinity (K(m) = 1.90 mM) and had a lower coupling ratio, more like 1 Na+ to 1 D-glucose. These characteristics resemble the properties of SGLT1 and SGLT2, which are known to coexist in the mammalian kidney. Inhibitor studies using sugar analogs and glucosides suggested structural differences of the D-glucose binding site among these transporters, whereas the hydrophobic transporter domains in the vicinity of the D-glucose binding site appeared to be similar. In the high-affinity skate system, D-glucose was recognized by hydrogen bonds to the hydroxy groups at C-2, C-3, and C-4 and by hydrophobic interaction with the C-6 methylene group. In contrast, the low-affinity shark system seemed to lack the hydrophobic recognition motif for the C-6 methylene group of D-glucose.

Genomic organization of the TcR beta-chain diversity (Dbeta) and joining (Jbeta) segments in the rainbow trout: presence of many repeated sequences

This work describes a 5.5 kb genomic sequence of the rainbow trout T-cell receptor beta-chain locus. It includes, from 5' to 3', a Dbeta gene, 10 Jbeta genes and the 5'-end of the first Cbeta exon. The trout Dbeta-Jbeta-Cbeta locus is about the same size as the mouse, rat and human homologous loci, but it is less compact and contains 10 Jbeta segments instead of the 6-7 found in mammals. The trout Dbeta coding sequence is identical to those of the mouse, rat and human Dbeta, and the Dbeta recombination signal sequences (RSS) are also very well conserved. Each trout Jbeta segment is flanked in 5' by a 7-mer RSS, which matches with the canonical conserved 7-mer sequences of all RSS. However, 6 of the 10 Jbeta segments have no characteristic 9-mer RSS, although at least some of them are well expressed (Jbeta1 and Jbeta2). The Jbeta region of the trout TcRbeta locus contains numerous micro/minisatellite repeated DNA sequences; some of these repeats contain heptamer RSS-like sequences that could interfere with Jbeta expression. Knowledge of the germline boundaries of the trout Dbeta and Jbeta ends makes it possible to evaluate precisely the exonuclease activity and N-nucleotide addition at the Dbeta-Jbeta junctions of the rearranged TcRbeta chain genes. Many (40%) of the Dbeta-Jbeta junctions in the adult trout have no N-nucleotides, compared to 26.4% in adult mice, and 37% of the adult trout TcRbeta transcripts are out of frame. Thus, there may be major differences in the T-cell developmental kinetics and selection in fish and mammals.

The unusual tetrasaccharide sequence GlcA beta 1-3GalNAc(4-sulfate)beta 1-4GlcA(2-sulfate)beta 1-3GalNAc(6-sulfate) found in the hexasaccharides prepared by testicular hyaluronidase digestion of shark cartilage chondroitin sulfate D

Eight hexasaccharide fractions were isolated from commercial shark cartilage chondroitin sulfate D by means of gel filtration chromatography and HPLC on an aminebound silica column after exhaustive digestion with sheep testicular hyaluronidase. Capillary electrophoresis of the enzymatic digests as well as one- and two-dimensional 500 MHz 1H-NMR spectroscopy demonstrated that these hexasacchrides share the common core saccharide structure GlcA beta 1-3GalNAc beta 1-4 GlcA beta 1-3GalNAc beta 1-4GlcA beta 1-3GalNAc with three, four, or five sulfate groups in different combinations. Six structures had the same sulfation profiles as those of the unsaturated hexasaccharides isolated from the same source after digestion with chondroitinase ABC (Sugahara et al., Eur. J. Biochem., 293, 871-880, 1996) and the other two have not been reported so far. In the new components, a D disaccharide unit, GlcA(2-sulfate)beta 1-3GalNAc(6-sulfate), characteristic of chondroitin sulfate D was arranged on the reducing side of an A disaccharide unit, GlcA beta 1-3GalNAc(4-sulfate), forming an unusual A-D tetrasaccharide sequence, GlcA beta 1-3GalNAc(4-sulfate)beta 1-4GlcA(2-sulfate)beta 1-3GalNAc(6-sulfate) which is known to be recognized by the monoclonal antibody MO225. These findings support the notion that the tetrasaccharide sequence, GlcA beta 1-3GalNAc(4-sulfate)beta 1-4GlcA beta 1-3GalNAc(6-sulfate) is included in the acceptor site of a hitherto unreported 2-O-sulfotransferase responsible for its synthesis. The sulfated hexasaccharides isolated in this study will be useful as authentic oligosaccharide probes and enzyme substrates in studies of sulfated glycosaminoglycans.

Analysis of VH gene diversity in rainbow trout (Oncorhynchus mykiss): both nonsynonymous and synonymous nucleotide changes are more frequent in CDRs than in FRs

Forty-six immunoglobulin VH gene sequences of rainbow trout were compiled to analyze the extent of variations and the frequency of nucleotide changes in CDRs and FRs. The results show that the frequency of nonsynonymous (amino acid replacing) changes (Ka) are on average 4.9 times higher in complementarity determining regions (CDRs) than in FRs, thus contributing more diversity in CDRs. Unexpectedly, however, the frequency of synonymous (silent) changes (Ks) show the same tendency: it was 5.3 times higher in CDRs than in framework regions (FRs). The distribution of Ks/Ka ratios of each comparison shows no segregation between CDRs and FRs. The same analysis applied to five germline VH genes of Heterodontus francisci shows the same result as was found with the rainbow trout. In contrast, the results from mouse data show that, while the CDR/FR ratio for Ka is much higher (7.4), the CDR/FR ratio for Ks is only slightly higher (1.8). The distribution of Ks/Ka ratios in mouse indicates clear segregation between CDRs and FRs. This suggests that CDR germline diversity is largely generated by gene conversion in VHs of lower vertebrates such as rainbow trout or shark. This mechanism might be advantageous to lower vertebrates in generating V gene diversity faster than other mechanisms such as point mutation and selection.

In vitro evidence for a Donnan distribution of Mg2+ and Ca2+ by chondroitin sulphate in cartilage

Fluoroquinolones are known for their ability to form chelate complexes with magnesium. Cartilage lesions observed in juvenile animals after quinolone treatment very probably are a consequence of the lack of functionally available magnesium. In cartilage, which contains high amounts of negatively charged proteoglycans, a Donnan distribution can be expected leading to an inhomogeneous distribution of ions (such as magnesium), which may support the toxic effects of magnesium deficiency or quinolone treatment of cartilage. We performed in vitro experiments using dialysis tubes to simulate the unequal distribution of proteoglycans in cartilage and measured the distribution of magnesium, calcium and ofloxacin. We found that the concentration of free magnesium is significantly reduced with the chondroitin sulphate-free solution due to a Donnan effect. For example, using a 3% chondroitin sulphate solution (outside the tubing) dialysed against a chondroitin sulphate-free solution (inside the tubing) the magnesium concentration decreased by 24% from 0.55 +/- 0.02 to 0.42 +/- 0.04 mmol/l inside the tubing during 48 h observation (P < 0.01). Under physiological conditions this unequal distribution of magnesium probably will be much more pronounced because chondroitin sulphate concentrations in cartilage are higher; nevertheless, magnesium concentration is sufficient for regular function of the tissue. During the sensitive phase of quinolone toxicity, magnesium in juvenile cartilage is lower than at other time points during postnatal development. Moreover, additional complexation by quinolones may further reduce the concentration of functionally available magnesium below the critical level.

EVOLUTION OF THE IMMUNE RESPONSE. I. THE PHYLOGENETIC DEVELOPMENT OF ADAPTIVE IMMUNOLOGIC RESPONSIVENESS IN VERTEBRATES

1. The California hagfish, Eptatretus stoutii, seems to be completely lacking in adaptive immunity: it forms no detectable circulating antibody despite intensive stimulation with a range of antigens; it does not show reactivity to old tuberculin following sensitization with BCG; and gives no evidence of homograft immunity. 2. Studies on the sea lamprey, Petromyzon marinus, have been limited to the response to bacteriophage T(2) and hemocyanin in small groups of spawning animals. They suggest that the lamprey may have a low degree of immunologic reactivity. 3. One holostean, the bowfin (Amia calva) and the guitarfish (Rhinobatos productus), an elasmobranch, showed a low level of primary response to phage and hemocyanin. The response is slow and antibody levels low. Both the bowfin and the guitarfish showed a vigorous secondary response to phage, but neither showed much enhancement of reactivity to hemocyanin in the secondary response. The bowfin formed precipitating antibody to hemocyanin, but the guitarfish did not. Both hemagglutinating and precipitating antibody to hemocyanin were also observed in the primary response of the black bass. 4. The bowfin was successfully sensitized to Ascaris antigen, and lesions of the delayed type developed after challenge at varying intervals following sensitization. 5. The horned shark (Heterodontus franciscii) regularly cleared hemocyanin from the circulation after both primary and secondary antigenic stimulation, and regularly formed hemagglutinating antibody, but not precipitating antibody, after both primary and secondary stimulation with this antigen. These animals regularly cleared bacteriophage from the circulation after both the primary and secondary stimulation with bacteriophage T(2). Significant but small amounts of antibody were produced in a few animals in the primary response, and larger amounts in the responding animals after secondary antigenic stimulation. 6. Studies by starch gel and immunoelectrophoresis show that the hagfish has no bands with mobilities of mammalian gamma globulins; that the lamprey has a single, relatively faint band of this type; and that multiple gamma bands are characteristic of the holostean, elasmobranchs, and teleosts studied. By this method of study, the bowfin appeared to have substantial amounts of gamma(2) globulin. 7. We conclude that adaptive immunity and its cellular and humoral correlates developed in the lowest vertebrates, and that a rising level of immunologic reactivity and an increasingly differentiated and complex immunologic mechanism are observed going up the phylogenetic scale from the hagfish, to the lamprey, to the elasmobranchs, to the holosteans, and finally the teleosts.