The proper course of biochemical processes and the optimal function of biological immune mechanisms is ensured by numerous bioregulatory active substances (Rompp Lexikon page 3826 "Regulation"). From a chemical standpoint, bioregulatory active substances known up to now are peptides, carbohydrates, steroids or lipids, whereby these structural elements can also occur together (for example, glycopeptides, lipoproteins). Furthermore, the application of bioregulatory active substances for the therapy of diseases which are caused by disturbed functions of one or more of these regulation mechanisms is known. The therapeutic use of steroid hormones, corticosteroids and cardiac glycosides as well as growth hormones or blood coagulation factors are some of the many examples in this sense. However, pharmacotherapy with substances of this type is very often accompanied by damaging side-effects, and therewith, considerably limited. A detailed consideration of these aspects is to be found in Goodman and Gilman's "The Pharmacological Basis of Therapeutics", 8th Ed., New York, 1991. For example, with cardiac glycosides, the positive inotropic, therapeutically useful action is compromised by a cardiotoxic side-effect, and consequently, therapeutic doses must be very rigorously limited. As a further example, the application of corticosteroids may be mentioned where the therapeutic use is only recommended in very severe cases and only for a limited time due to a series of very severe side-effects such as myopathy, osteoporosis, psychic disturbances, increased infection susceptibility, etc.
Despite considerable efforts to treat immunologically caused disease syndromes with immunoregulatory active substances, previous clinical tests are not convincing. The purpose of such immunotherapeutic applications would be to accomplish the basic therapy for autoimmune diseases such as rheumatoid arthritis and multiple sclerosis, among others, which has not been found to date. According to E. Sercarz and S. K. Datta "Autoimmunity" in Current Biology 6, 875-881 (1995), these autoimmune diseases have mostly been caused by disturbed immunoregulation. For fighting severe disease syndromes which are characterized by a considerably weakened immune system, such as carcinosis or AIDS, the previous therapeutical uses of immunoregulatory substances has yielded little.
Several bioregulatory peptides and proteins have been characterized as reported in the Monograph from M. J. Clemens "Cytokines", Oxford 1991. That cytokines play an important role in different carcinoses, in autoimmune diseases and in viral infections (including AIDS) has also already been reported several times. Despite this, wider therapeutic applications of these and other bioregulatory proteins and peptides are still lacking to a large extent. One of the causes for this certainly lies in the often very laborious production technologies: the extractions and subsequent purifications of bioregulatory active substances from human or animal tissue fluids, where they are present in only very small amounts, is completely unsuitable for providing therapeutically needed amounts. The danger of allergic side-effects and/or anaphylactic reactions which, despite their rare occurrence, represent a considerable risk factor for human therapy that still exists with gene technologically produced bioregulatory polypeptides or glycoproteins. The fundamental problem of the therapeutic applications of several "in vitro" highly active polypeptide factors lies in the fact that they demonstrate "in vivo" entirely different, mostly very much weaker activity. On the one hand, numerous physical and enzymatic barriers impede the externally administered peptides and proteins from reaching the location of the pathological event (focus of inflammation, cancerous ulcer, etc.). On the other hand, they are quickly neutralized and metabolized by the endogenous enzymes and other factors present there. With peroral administration of active substances of a peptide, glycopeptide and glycosidic nature, these substances are already rendered practically ineffective in the gastrointestinal system by several degradation processes.
However, a relatively fast degradation of bioregulatory active substances of peptidic or glycopeptidic nature must also be taken into account with a delivery "per os". In order to entirely target the therapeutically effective concentration to the location of the pathological event or manifestations, such as at the focus of inflammation or at the cancerous ulcer, a masked delivery of the active substance has been performed for example. Something similar was described by R. Collier and D. Kaplan in "Immuntoxine", Heidelberg 1988, in connection with the use of toxins which could be purposefully employed bound to monoclonal antibodies(drug targeting). However, the treatment technique is still very complicated and only remains restrictively applicable for specific cases. For regulatory active substances, the bioavailability is not only dependent on stability, but also on purely physical processes, such as solubility and membrane permeability. This concerns making the water solubility of lipophilic substances possible in plasma or making the membrane permeability of hydrophilic active ingredients such as Na.sup.+ or K.sup.+ ions possible. For example, the mitochondria membrane is normally not permeable to potassium ions. Macrocyclic antibiotics such as nonactin or valinomycin make this permeability possible through the organic envelopment of the corresponding ions.
Since 1967, the year of discovery of the "crown ethers", numerous new compounds have been produced which have a macroring structure and make a crown or cryptate-like covering of inorganic ions or smaller molecules possible. However, important prerequisites for a direct therapeutic application of such cryptate-forming macrocyclic substances are a low toxicity and good bioassimilation, which is only seldom fulfilled by the synthetically produced cryptand reagents.
Many fundamental bioregulatory mechanisms are controlled by the so-called sodium pump. This enzyme has the ability to pump sodium ions from the insides of cells to the outside and simultaneously transport potassium ions in the opposite direction. The energy consumption is delivered by a coupled hydrolysis of adenosine triphosphate (ATP). This pump is identical with the enzyme referred to as the Na.sup.+,K.sup.+ -ATPase and is ubiquitously distributed. Several important cellular functions are controlled by this Na.sup.+,K.sup.+ -ATPase such as cell volume, heat production, intracellular free Ca.sup.2+ ion concentration, neuronal transmission, muscle contraction or membrane potential.
In numerous immunoregulatory processes, important phases are also controlled by the Na.sup.+,K.sup.+ -ATPase, and thus, the sodium pump also acquires a fundamental roll in immunoregulation. Despite this general distribution and significance, the regulation mechanism of this enzyme has not yet been clarified. The so-called "cardiac glycoside receptor site" of the enzyme is suspected as the functional location for the bioregulation of the sodium pump. The cardiac glycosides present in several plant species are bound to this site with high affinity and exert their cardiotonic, but also their cardiotoxic effect. However, their toxicity proves that they are not identical with the endogenous ligands of this enzyme. In the paper "Endogenous digitalis-like factors" by W. Schoner in Progress in Drug Research, 41, 249-291 (1993), it is reported that the chemical nature and the structure of these endogenous bioregulatory substances could not yet be established despite a large research effort. Up to now, no sufficient amount of these endogenous factors could be isolated from animal tissue and fluids in order to make an exact characterization and structure determination possible. The activity of the Na.sup.+,K.sup.+ -ATPase, and therewith several bioregulatory mechanisms, could be effectively controlled with factors which are identical or structurally similar to these endogenous ligands.
Recently, several simple inorganic substances have been found which participate in bioregulatory processes. However, it is important to note that all of these inorganic substances are only used as simple messenger substances or effectors. They fundamentally lack the three-dimensional structure necessary for exerting a bioregulatory action and the capability for structure specific action coupled therewith. In the paper "Biological Roles of Nitric Oxide" by S. Snyder and D. Bredt in Scientific American, 1992 (5) 22-29, it is reported that this gaseous compound is a functional effector in the control of the non-specific immune response. In the organism, nitric oxide had a very short life time in order to exert its local, mostly toxic effect and is always produced "in situ". When the phagocytes of the immune system, the so-called macrophages, are activated with bacterial toxins or cytokines, they can produce relatively large amounts of nitric oxide within hours and this is employed as an immunological weapon. It is assumed that further simple gaseous compounds also participate in bioregulatory processes. Ethylene, for example, is known as an important factor in plant biology. Carbon monoxide participates in the physiological regulation of the cyclization of guanosine monophosphate (GMP) as was reported by A. Verma in Science, 259, 381 (1993).
Only very little has been reported up to now on the biological action of another carbon oxide, the much more seldom found C.sub.3 O.sub.2. It is only known that this concerns a compound which is gaseous at room temperature (bp 7.degree. C.), is irritating to mucus membranes and smells of mustard oil and acrolein. Carbon suboxide represents a relatively strong blood toxin which irreversibly binds hemoglobin; the tolerability limit in mice lies at 0.2-0.4% C.sub.3 O.sub.2 in dry air. C.sub.3 O.sub.2 reacts with water and forms malonic acid. However, without traces of mineral acids, this reaction does not proceed so fast as it was previously claimed. It is suspected that, aside from carbon monoxide, the primitive reducing earth atmosphere also contained considerable amounts of C.sub.3 O.sub.2, and recently, evidence of its possible presence in interstellar space was found as reported by W. Huntress et al. in Nature, 352, 316-318 (1991). However, until now there is no concrete evidence for the possible presence of C.sub.3 O.sub.2 in biological fluids. Considering the water sensitivity of the monomer gas as well as the amorphous polymer, a possible biological role has been mostly excluded a priori. The hypothesis of H. Yanagawa and F. Egami in Precambrian Research, 14, 75 (1981), whereby the water reactive amorphous polymer could have been a possible starting material for the original synthesis of simple organic compounds, has been considered as fundamentally possible. Gaseous C.sub.3 O.sub.2 more or less quickly forms amorphous polymers which are yellow to intensive red-brown colored. Only very little concrete knowledge is known on the structure of these polymers. In general, they are described as a non-homogeneous amorphous mass which was also earlier designated as "red carbon". The chemical properties of carbon suboxide and its polymers are reviewed in the paper by T. Kappe and E. Ziegler, Agnew. Chem., 86, 529 (1974). The polymerization products are partially soluble in water or in diluted alkalines, whereby intensive yellow to dark brown colored solutions are formed. Several hypothetical formulae have been proposed for the structure of these amorphous, irregular polymers, but none of them could also be experimentally confirmed. As the most probable, a graphite-like, hexagonal lattice structure is suspected which is unsaturated at the periphery and must be correspondingly unstable. This hypothesis was described in detail in the paper by N. S. Smith and D. A. Young in Inorganic Chemistry 2, 829 (1963).
It is further known that several biologically highly effective substances in plasma are not found as such, but rather as conjugates. For example, steroid hormones are present in blood plasma as their sulfate or glucuronate conjugates and their degradation products are also eliminated as such conjugates. Not infrequently, these conjugated steroids demonstrate even better therapeutic properties in comparison with the pure active substance, as was described for conjugated estrogen steroids according to U.S. Pat. No. 2,565,115 and U.S. Pat. No. 2,720,483 or for dehydroepiandrosterone sulfate (DHEAS). The above mentioned conjugations regulate the biological availability and the assimilation of these steroid active substances and can therewith explain the improved therapeutic properties. Relatively little is known about the regulation of the bioavailability of polypeptidic active substances by the formation of corresponding conjugates. The enzymatic conjugation of proteins with ubiquitin also has regulatory functions as was described in Trends Biochemical Sciences 15, 195 (1990). The suitable conjugation of polypeptidic substances could attain a breakthrough in the therapeutic applications of these active substances. As a known example, the search for retard acting insulin is to be mentioned. It is known that the therapeutic functional time of insulin is considerably prolonged by addition of zinc salts or of protamine sulfate. However, these additives can cause different side-effects. A suitable conjugate which should ensure a retarded release of insulin has been tried by numerous inventors, but until now has not be realized.
USPTO Backgrounds
USPTO Backgrounds