Metabolic fate of cyanocobalamin taken up by Spirometra mansonoides spargana.

Analysis of tissue from Spirometra mansonoides spargana has shown that cyanocobalamin (vitamin B12) is metabolized to adenosylcobalamin and hydroxocobalamin. No methylcobalamin was detected. When the tissues were examined for enzymes which are known to utilize coenzyme forms of vitamin B12, only methylmalonyl CoA mutase, which requires adenosylcobalamin was found. The enzyme, tetrahydropteroylglutamate methyltransferase, which requires methylcobalamin as a cofactor, was not detected. A sizable portion of the cyanocobalamin taken up was bound to ammonium sulfate-precipitable material, suggesting that the binding substance is a protein. Vitamin B12 taken up by spargana was found to be released in vivo with a biological half-life of about 7 weeks.     

Comparison of isozyme patterns between Spirometra erinacei and Spirometra mansonoides by isoelectric focusing.

No differences were observed in the isozyme patterns of 4 enzymes examined between fresh samples stored at -80 C and samples stored at room temperature for 10 days after lyophilization, which supports the validity of comparing lyophilized samples to fresh frozen tissue. Mature proglottids as well as plerocercoids of Spirometra erinacei from Japan and Australia were indistinguishable by comparison of isozyme patterns after isoelectric focusing. The isozyme patterns of acid phosphatase, glucosephosphate isomerase (GPI), and mannosephosphate isomerase from plerocercoids of Spirometra mansonoides were distinctly different from those of plerocercoids of S. erinacei. The adenylate kinase isozyme patterns of the mature proglottids of S. mansonoides were also distinctly different from those of the mature proglottids and the plerocercoids of S. erinacei. The GPI isozyme pattern of the mature proglottids of S. mansonoides was also distinguishable from the GPI patterns of those of S. erinacei. These electrophoretic data suggest that the S. erinacei from Japan and Australia are closely related, if not identical, but that S. mansonoides is genetically distinct from S. erinacei.     

Spirometra mansonoides: lectin analysis of tegumental glycopeptides

Teguments from spargana of Spirometra mansonoides were disrupted and removed using 0.2% Triton ×-100. Tegumental fractions were obtained by differential centrifugation and the proteins and glycoproteins of this surface layer were partially characterized in 9 to 20% linear gradient sodium dodecyl sulfate-polyacrylamide slab gels. Electrophoretic analysis of the microtriches (brush border) and vesicular fractions revealed nine polypeptides that were common to these tegumental fractions. The polypeptide composition of the microtriches and vesicular fractions differed qualitatively and with respect to the relative concentrations of certain polypeptides. Glycopeptides of the microtriches and vesicular fractions were identified by the direct application of the following fluorescein isothiocyanate-conjugated lectins to slab gels: concanavalin A, wheat germ agglutinin, Ricinus communis agglutinin-120, soybean agglutinin, and Ulex europaeus agglutinin-1. The major polypeptides associated with the tegument were found to be glycopeptides. U. europaeus agglutinin-1 failed to label any tegumental glycopeptides. Based on the different sugar specificities of the lectins tested, the oligosaccharide chains of tegumental glycoproteins of S. mansonoides may contain the following carbohydrates: d-mannose, d-glucose, N-acetyl-d-glucosamine, N-acetylneuraminic acid, d-galactose, and N-acetyl-d-galactosamine.     

Spirometra mansonoides: effects of plerocercoid infection on glycogen deposition in rats

The effects of infection with plerocercoids of Spirometra mansonoides on tissue glycogen deposition of rats was determined. Hypophysectomized rats infected for two days had higher liver glycogen concentrations than controls and this effect was greatest after one week. Elevated liver glycogen associated with plerocercoid infection was observed in fed animals both at the beginning and at the end of the light period as well as after an overnight fast. Glycogen phosphorylase (1,4 alpha D glucan: orthophosphate alpha glucosyltransferase EC 2.4.1.1.) was inhibited but glucose-6-phosphatase (EC 3.1.3.9) was unaffected in the livers of infected hypophysectomized rats. While this effect is similar to actions of both growth hormone and insulin, plerocercoid infection had no influence on glycogen of cardiac or skeletal muscle at any time. Plerocercoid infection had no effect on the glycogen concentration of any tissue of intact rats.     

Effects of putative neurotransmitters on the motor activity of Spirometra mansonoides.

5-Hydroxytryptamine (5-HT), epinephrine, and dopamine strongly stimulated the motor activity of larval Spirometra mansonoides. By contrast, a cholinomimetic agent, arecoline, paralyzed the worms. There was some pharmacological specificity among the agonists but not with various antagonists. Acetylcholinesterase activity was present in both larval and adult Spirometra.     

Genetic diversity of two mitochondrial DNA genes in Spirometra erinaceieuropaei (Cestoda: Diphyllobothridae) from Poland

The tapeworm species Spirometra erinaceieuropaei was documented mainly in Asia and Europe. In recent years, plerocercoid larvae (spargana) of this parasite have been found in different hosts in north‐eastern Poland. The evolutionary history and way of S. erinaceieuropaei spreading across Eurasia have been not described yet. However, this phenomenon could be closely related to the evolutionary history and migration routes of studied tapeworm host species. We investigated the genetic variability and divergence pattern among S. erinaceieuropaei populations in intermediate and paratenic hosts from north‐eastern Poland based on complete mitochondrial sequences of cytochrome b (cytb) and cytochrome c oxidase subunit I (cox1) genes. Analysis of 319 consolidated sequences of these two genes showed no genetic structure across study area. Comparison of sequences from Poland and China showed distinct separation of S. erinaceieuropaei populations from these two regions. They split from their common ancestor approximately 28.6 million years ago. Demographic expansion of Polish population of S. erinaceieuropaei started from glacial refugia approximately 12.5 thousand years ago, and recent population expansion has been observed in the tapeworm population from north‐eastern Poland.     

Insulin-like effects in the rat of the purified growth factor from Spirometra mansonoides plerocercoids

The acute effects of injections of the human growth hormone-like factor purified from plerocercoids of the tapeworm Spirometra mansonoides on carbohydrate, lipid, and protein metabolisms were determined in intact rats. Male rats were injected ip with saline, insulin, or various doses of partially purified PGF. The rats injected with insulin had significantly reduced serum glucose concentrations but no dose of PGF caused a change in serum glucose levels. Insulin and PGF stimulated [14C]glucose and [14C]leucine oxidation to 14CO2 in adipose tissue and muscle and increased incorporation of both [14C]glucose carbons into lipids and [14C]leucine into protein in fat and muscle. The responses to PGF were dose-dependent and persisted after 3 hr of incubation in vitro. Injections of naloxone prior to injecting PGF to block the stress response did not prevent the stimulation of insulin-like responses by PGF. Therefore, PGF has intrinsic insulin-like activities in normal male rats.