Chemistry: analytical and immunological testing – Peptide – protein or amino acid
Reexamination Certificate
2001-07-05
2004-04-13
Warden, Jill (Department: 1743)
Chemistry: analytical and immunological testing
Peptide, protein or amino acid
C436S164000, C436S172000, C435S069600, C435S069700
Reexamination Certificate
active
06720188
ABSTRACT:
BACKGROUND OF INVENTION
L-arginine is a substrate for nitric oxide synthases (NO synthases) and is a precursor of nitric oxide (NO), a major cell signaling molecule implicated in the regulation of many cellular pathways. The L-arginine: NO pathway has been implicated in the regulation of the cardiovascular, nervous and immune systems. Inhibitors of NO have been shown to increase blood pressure in guinea pigs and rabbits (Aisaka et al
Biochem. Biophys. Res. Commun
. (1989) 160:-881-886; Rees et al.
PNAS
(1989) 86:3375-3378), and to induce arteriolar vasoconstriction in humans (Vallance et. al. (1989)
Lancet
8670:997-1000). A variety of arginine analogs were identified which modulate the L-arginine:NO pathway (for review see Leiper and Vallance,
Cardiovascular Research
, 43, 1999, 542-548). These include N
G
-monomethyl-L-arginine (L-NMMA), N
G
-, N
G
-dimethylarginine (ADMA; asymmetric dimethyl arginine) and N
G
′-, N
G
-dimethylarginine (SDMA; symmetric dimethylarginine).
SUMMARY OF INVENTION
In one embodiment, the invention pertains to a method for determining arginine compound levels in body samples of a subject. The method includes contacting a body sample with an arginine sensing substance, and analyzing the resulting mixture. Examples of preferred body samples include, body fluids such as blood, saliva, sweat and urine. In an advantageous embodiment, the body sample is obtained non-invasively. In particular preferred embodiment, the arginine compound level is analyzed through a color change, e.g., a change in optical characteristics or fluorescence, of the arginine compound sensing substance and body fluid mixture. Such determination could determine need for therapy administration or other interventions. Examples of arginine, N
G
-compounds include L-arginine and derivatives of arginine such as methyl arginine, monomethyl-L-arginine (L-NMMA), N
G
, N
G
-dimethylarginine (ADMA; asymmetric dimethyl arginine) and N
G
′, N
G
-dimethylarginine (SDMA; symmetric dimethylarginine).
The invention also pertains to a kit suitable for determining arginine compound levels in a subject. Preferably, the kit includes direction for use. In one embodiment of the kit, the arginine sensing substance is embedded in a solid, permeable substrate. In another embodiment the kit includes a vial for mixing an arginine (or arginine compound) sensing substance with a body sample.
The invention also pertains, at least in part, to arginine compound recognizing substances of the formula (I):
G(N)
n
(C)
m
(I)
wherein
G is a guanidinium recognizing moiety;
N is an ammonium recognizing moiety;
C is a carboxylate recognizing moiety; and
n and m are each independently integers from 0 to 10.
DETAILED DESCRIPTION OF THE INVENTION
Arginine (Arg) and asymmetric dimethylarginine (ADMA) are present in human bodily fluids, such as serum and urine, and are derived from the catabolism of proteins containing arginine and methylated arginine residues (Cooke, J. P.
Arterioscler. Thromb. Vasc. Biol
. 2000, 2032-2037). Levels of ADMA is further regulated via metabolic pathways, such as the major one involving the enzyme dimethylarginine dimethylaminohydrolase (DDAH). Bodily production of nitric oxide (NO), the critical modulator of blood flow and blood pressure (Rees, D. D.; et al.
PNAS
, 1989, 86, 3375-3378), occurs through metabolism of arginine by the specific enzyme nitric oxide synthase (NOS). While arginine is utilized for NO synthesis, endogenous ADMA, on the contrary, downregulates NO production by inhibiting NOS. Abnormal concentrations of ADMA can serve as indications of various disorders, such as renal failure, endothelial dysfunction, and vascular diseases in general (Cooke, J. P.
Arterioscler. Thromb. Vasc. Biol
. 2000, 2032-2037). Levels of available arginine are very important for NO synthesis in patients with hypercholesterolemia or atherosclerosis. Thus, detection of arginine and ADMA levels in bodily fluids is useful for diagnosis and treatment of these diseases.
The invention pertains, at least in part, to methods and kits for determining levels of arginine compounds in a body sample. In one embodiment, the invention pertains to a diagnostic kit that can detect levels of arginine compounds in body sample. The invention includes methods for determining the appropriate levels of an arginine compound, to administer to a subject who may be suffering from aberrant arginine compound levels due to an arginine compound related disorder.
In one embodiment, the invention pertains to a method for determining arginine compound levels in a body sample. The method includes contacting a body sample with a arginine sensing substance, and analyzing the resulting mixture. Preferably, the arginine sensing substance is a arginine compound recognizing substance.
The term “body sample” includes body fluids and tissues which may potentially contain arginine compounds. The term “body sample” also includes body fluids. The term “body fluids” includes all fluids obtained from a mammalian body, including, for example, blood, plasma, urine, serum, saliva, sweat, and spinal and brain fluids. In an embodiment, the arginine compound is methyl arginine, L-NMMA, ADMA, SDMA or L-arginine. Furthermore, the body sample may be either processed (e.g., serum, crushed cellular material) or unprocessed.
The term “arginine compound” includes L-arginine and derivatives of arginine such as methyl arginine, N
G
-monomethyl-L-arginine (L-NMMA), N
G
, N
G
-dimethylarginine (ADMA; asymmetric dimethyl arginine) and N
G′
, N
G
-dimethylarginine (SDMA; symmetric dimethylarginine). Other arginine derivatives which can be identified using the methods and compositions of the invention are also included. Certain arginine compounds are shown in Table 1.
TABLE 1
L-Arginine
ADMA
L-NMMA
SDMA
L-NMMA, an arginine compound, has been found to inhibit the cytotoxic effects of activated macrophages and to prevent the release of nitrate and nitrite derived from L-arginine within these cells. After Furchgott's endothelium-derived relaxing factor was identified as nitric oxide (Palmer et. al.,
Nature
(1987) 327:524-526), it was discovered that L-NMMA inhibited the generation of endolethial NO from L-arginine (Palmer et. al.,
Nature
(1988) 333:664-666). Subsequently, L-NMMA became a tool to probe into the functions of the L-arginine:NO pathway.
L-NMMA is found naturally in cells as an arginine analog. Additionally, asymmetric and symmetric dimethylarginines have been identified. These substituted methyl arginine compounds affect arginine handling and modulate NO synthesis and its regulated pathways. Determining levels of arginine and other arginine compounds (e.g., methylated derivatives) in tissues and body fluids has a predictive and diagnostic value in predisposition or progression of NO associated disorders.
The arginine compounds, ADMA and SDMA, are the major circulating forms of methylarginine in humans. The presence of methylated arginine residues was noted within specialized proteins including myelin basic protein, heat shock proteins, nuclear and nucleolar proteins (Lischwe et. al.,
J. Biol. Chem
. (1985) 260:14304-14310; Lischwe et al.
Biochemistry
(1985) 22:6025-6028) but their function remains unclear. A series of protein-arginine methyl transferase enzymes have been identified (Paik et. al.
J Biol. Chem
. (1968) 243:2108-2114; Ghosh et. al.,
J. Biol. Chem
. (1988) 263:19024-19033). Some have wide substrate specificity such as histone and non histone nuclear proteins and others are more selective. These enzymes can generate L-NMMA and SDMA methylated arginines or L-NMMA and ADMA methylated arginines. The production of methylarginine residues is highly regulated and results in the regulation of several signalling pathways. Proteolysis of proteins containing methylarginine residues leads to the release of free methylarginine residues into the cytoplasm (Kakimoto et. al.,
J. Biol. Chem
. (1970) 245:5751-5758).
Initially it was assumed that following proteolysis the released methylarginine are released
Bell Thomas W.
Kaddurah-Daouk Rima
Khasanov Alisher B.
Cynthia M. Soroos, Esq.
Elizabeth A. Hanley, Esq.
FAL Diagnostics
Gakh Yelena
Lahive & Cockfield LLP
LandOfFree
Methods and kits for the detection of arginine compounds does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Methods and kits for the detection of arginine compounds, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Methods and kits for the detection of arginine compounds will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3213831