AU2012216555B2 - Peptide fragments for inducing synthesis of extracellular matrix proteins - Google Patents

Abstract

Short biologically active tetrapeptides are disclosed that are comprised of the sequences GxxG and PxxP where G (glycine) and P (proline) are maintained and x is a variable amino acid. The peptides can be used singly or in combination to stimulate production of extracellular matrix proteins in skin. A rapid, low-cost method of producing heterogenous formulations of tetrapeptides is disclosed.

Description

AUSTRALIA PATENTS ACT 1990 REGULATION 3.2 Name of Applicant: HELIX BIOMEDIX INC. Actual Inventor/s: Scott M. Harris; Lijuan Zhang; and Timothy J. Falla. Address for Service: E. F. WELLINGTON & CO., Patent and Trade Mark Attorneys, 312 St. Kilda Road, Melbourne, Southbank, Victoria, 3006. Invention Title: "PEPTIDES FRAGMENTS FOR INDUCING SYNTHESIS OF EXTRACELLULAR MATRIX PROTEINS" Details of Associated Provisional Applications Nos: The following statement is a full description of this invention including the best method of performing it known to us. -l-

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CROSS REFERENCE TO RELATED APPLICATIONS [ooo1 This application is a 'divisional' application derived from Australian Patent Application No. 2007258387 (PCT/US2007/013748: WO 2007/146269), claiming priority of US Application No. 60/813284, the entire text of which are hereby incorporated herein by reference. FIELD OF THE INVENTION (00021 The invention relates to tetrapeptides with the amino acid motif GxxG or PxxP, where 0 (glycine) and P prolinee) are maintained and x is a variable amino acid. The invention also relates to frame shift active tetrapeptides which are tetrapeptide sequences shifted one frame from a GxxG or PxxP tetrapeptide in an ECM protein. In particular, the invention relates to OxxG, PxxP, or frame shift active peptides that stimulate production of extracellular matrix proteins and enhance wound closure of the epithelial cell monolayer of scratch-wounded human skin. The peptide compositions may be used in formulations for repairing damaged skin or maintaining healthy skin. BACKGROUND OF THE INVENTION 100031 Skin aging is commonly viewed as wrinkle formation and impaired wound healing. A wound is defined as a break in the epithelial integrity of the skin. Normal wound healing involves a complex and dynamic but superbly orchestrated series of events leading to the repair of injured tissues. The largest component of normal skin is the extracellular matrix (ECM), a gel-like matrix produced by the cells that it surrounds. The ECM is composed of two major classes including fibrous structural proteins and proteoglycans. Changes in the composition and crosslinked state of the ECM are known to be associated with aging and a range of acquired and heritable skin disorders. It has been well documented that ECM not only provides structural support, but also influences cellular behavior such as differentiation and proliferation. Also, more and more research suggests that the matrix components may be a source of cell signals to facilitate epithelial cell proliferation and migration and thus enhance wound healing. 100041 The largest class of fibrous ECM molecules is the collagen family, which includes at least 16 different types of collagen. Collagen in the dermal matrix is composed primarily of type I (80-85%) and type III (8-11%) collagens, both of which are fibrillar, or rod-shaped, collagens. The tensile strength of skin is due predominately to these fibrillar collagen molecules, which self-assemble into microfibrils in a head-to-tail and staggered side-to-side lateral arrangement.

-2 Collagen molecules become cross-linked to adjacent collagen molecules, creating additional strength and stability in collagen fibers. Damage to the collagen network (e.g. by enzymes or physical destruction), or its total collapse causes healing to take place by repair. gcoosi Various bioactive peptides that stimulate production of ECM proteins have been reported in both the scientific literature and in issued patents. Peptides historically have been isolated from natural sources and have recently been the subject of structure-function relationship studies. Natural peptides have also served as starting points for the design of synthetic peptide analogs. 100061 Specific sequences within ECM proteins can stimulate useful elements in skin, such as type I collagen, type III collagen, and fibronectin (Katayama et. al., J. BIOL. CHEM. 288:9941 9944 (1983)). Katayama et al. identified the pentapeptide, KTTKS (SEQ ID NO:17), within the carboxy-terminal propeptide (residues 197-241) of type I collagen. The propeptide is cleaved during production of the mature collagen protein. The cleaved propeptide may participate in regulating collagen production via a biosynthesis feedback mechanism, with the KTIKS segment playing an active role. Maquart et al. (J Soc BIOL. 193:423-28 (1999)) reported that the peptides GHK and CNYYSNS also stimulate ECM synthesis. These sequences may be released during ECM turnover, thereby signaling the need for ECM repair. The short peptide sequences liberated by either mechanism are often called "matrikines" (Maquart et al., J. Soc. BoL. 193:423-28 (1999)). [00071 While a number of natural and synthetic peptides exist, there is a need for improved biologically active peptides and methods for their use. SUMMARY OF THE INVENTION 100081 Tetrapeptides are disclosed that are characterized by the amino acid sequence motif GxxG or PxxP, where Q (glycine) and P (proline) residues are maintained and x is a variable amino acid. The tetrapeptides are derived from sequences that occur multiple times throughout the primary sequence of the ECM protein, type IV collagen. The disclosed sequences induce production of all forms of collagen more than previously known peptide sequences, including KTTKS, sold under the trademark MATRIXYLTM by SEDERMA SAS (France). Further, a composition comprising a combination of various multiply-repeating sequences elicits an even greater collagen-producing response. Additional benefits may be expected from peptide combinations present in a variety of ECM proteins.

-3 weCi Producing a specific combination of tetrapeptides for ECM rebuilding can be commercially cost-prohibitive. A relatively simple and cost-effective means of producing a diverse combination of biologically active tetrapeptides is disclosed. By producing a combinatorial library of tetrapeptides with the OxxG or PxxP motif, a variety of biologically active tetrapeptides can be generated in the same manufacturing run (e.g., GEPO, GPEO, GPPG, and GEEG). The combination of tetrapeptides may induce more formation of ECM proteins than single peptides. Compositions comprising the disclosed tetrapepides, alone or in combination, are useful in skin care markets including, but not limited to, those that address skin wrinkling, toning, firmness, or sagging. The stimulation of collagen by the disclosed tetrapeptides can significantly improve the health and appearance of damaged and aged skin. BRIEF DESCRIPTION OF THE FIGURES 100101 FIG. 1 is SEQ ID NO:45 which is the Collagen IV amino acid sequence illustrating the occurrences of GxxG tetrapeptides. All bold sequences are underlined and overlapping sequences are double-underlined. iooi FIG. 2 is SEQ ID NQ:46 which is the Collagen III amino acid sequence illustrating the occurrences of the frame shift actives PGPR and GAGP. All frame shift active sequences are bold and underlined and the QxxG sequences occurring one frame shift away are double underlined. 100121 FIG. 3 is also SEQ ID NO:45, the Collagen IV amino acid sequence, illustrating the occurrences of the tetrapeptide PGPP. DETAILED DESCRIPTION OF THE INVENTION oo1i The invention is generally directed towards tetrapeptides that stimulate production of ECM proteins and modulate wound healing, and uses of such tetrapeptides. Peptides 100141 One embodiment of the invention is directed towards an isolated tetrapeptide comprising the motif GxxQ or PxxP. In this embodiment G (glycine) or P (proline) is maintained and x is a variable amino acid. The peptide can generally be any peptide that falls within the above description, and more preferably is SEQ ID NO:I, SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO;5, SEQ ID NO:7, SEQ ID NO:8, SEQ'ID NO:9, SEQ ID NO:10, SEQ ID NO:11, SEQ ID NO:12. SEQ IL NO:13, SEQ ID NO:14, SEQ ID NO:15, or SEQ ID NO:16.

-4 1001si Another embodiment of the invention is directed towards an isolated tetrapeptide comprising the motif GxPG, where x is P at either variable position, or both. In this embodiment, G (glycine) and P (proline) are maintained and x is a variable amino acid. The peptide can generally be any peptide that falls within the above description, and more preferably is SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO:5, or SEQ ID NO:7. 100161 Another embodiment of the invention is directed towards an isolated tetrapeptide comprising the motif GExG. In this embodiment, O (glycine) and E (glutamic acid) are maintained and x is a variable amino acid. The peptide can generally be any peptide that falls within the above description, and more preferably is SEQ ID NO:5 or SEQ ID NO:8. [00171 Another embodiment of the invention is directed towards an isolated tetrapeptide comprising the motif PGxP. In this embodiment, P (proline) and G (glycine) are maintained and x is a variable amino acid. The peptide can generally be any peptide that falls within the above description, and more preferably is SEQ ID NO: 1l, SEQ ID NO:12, SEQ IID NO:14, or SEQ ID NO:16. oolsi Another embodiment of the invention is directed towards an isolated tetrapeptide comprising the motif PExP. In this embodiment, P (proline) and E (glutamic acid) are maintained and x is a variable amino acid. The peptide can generally be any peptide that falls within the above description, and more preferably is SEQ ID NO:1 or SEQ ID NO:9. i0191 Another embodiment of the invention is directed towards a frame shift active tetrapeptide. In this embodiment, the tetrapeptide occurs one frame shift from either a GxxG or PxxP tetrapeptide in an ECM protein. The peptide can generally be any peptide that falls within the above description, and more preferably is SEQ ID NO:4 or SEQ ID NO:6. 1oozo1 Each of the above-described peptides can comprise D- or L-amino acids. The peptides can comprise all D-amino acids or L-amino acids. The peptides can have an acid C-terminus (

CO

2 H) or, preferably, an amide C-terminus (-CONH 2 , -CONHR, or -CQNR 2 ). The peptides may be further augmented or modified, either chemically or enzymatically. For example, the peptides may be amidated (-NH 2 ) on the C-terminus, which may render the tetrapeptide less susceptible to protease degradation and increase their solubility compared to the free acid forms. The peptides may also be lipidated which may provide for enhanced skin penetration. 100211 The above-described peptides may contain the following amino acids: R (arginine), L (leucine), P (proline), F (phenylalanine), Q (glutamine), E (glutamic acid), I (isoleucine), K -5 (lysine), S (serine), V (valine), A (alanine), N (asparagine), D (aspartic acid), T (threonine), Y (tyrosine) and G (glycine). The above-described peptides do not include the following M (methionine), C (cysteine), H (histidine) or W (tryptophan). Accordingly, in one embodiment, x is nQt selected from either (methionine), C (cysteine), H (histidine) or W (tryptophan). Methods of Use 100221 An additional embodiment of the invention is directed towards methods of using the above-described peptides. The methods of use may involve the use of a single peptide, or may involve the use of two or more peptides in combination. ioozi An embodiment of the invention is a method of promoting repair of damaged skin and maintenance of healthy skin using tetrapeptides that stimulate production of ECM proteins. The method generally is directed towards contacting dermal (skin) cells with a composition containing the peptide. The compositions can be an aerosol, emulsion, liquid, lotion, cream, paste, ointment, foam, or other pharmaceutically acceptable formulation. Generally, a pharmaceutically acceptable formulation would include any acceptable carrier suitable for use on human skin, e.g. cosmetically acceptable carrier and dermatological acceptable carrier. The compositions may contain other biologically active agents such as retinoids or other peptides. The compositions may contain pharmaceutically acceptable carriers or adjuvants. The contacting step can be performed in vivo, in situ, in vitro, or by any method known to those of skill in the art. Most preferably, the contacting step is to be performed topically at a concentration sufficient to elicit a stimulatory response. The concentration of the peptide in the composition can be about 0.01 ptg/mL to about 100 gg/mL, about 0.1 pg/mL to about 50 JLg/mL, and about 0.1 pg/mL to about 1 jig/mL. The contacting step can be performed on a mammal, a cat, a dog, a cow, a horse, a pig, or a human. A preferred composition for promoting ECM protein production comprises SEQ ID NO:8; more preferably, the composition comprises SEQ ID NO:8 in a heterogeneous mixture with at least one other tetrapeptide. In a most preferred embodiment, the individual tetrapeptides in the composition would cause sustained collagen production over a period of at least 48 hours. 1o2i An additional embodiment of the invention is directed towards a method for promoting wound healing of skin damaged by normal aging, disease, injury, trauma, or by surgery or other medical procedures. The method can comprise administering to the wound of an animal a composition, wherein the composition comprises any of the above-described peptides, singularly -6 or in combination. The compositions can be a liquid, lotion, cream, paste, ointment, foam, or any other pharmaceutically acceptable formulation. The compositions may contain pharmaceutically acceptable carriers or - adjuvants. The compositions may contain other biologically active agents such as antimicrobial agents or growth factors. The compositions may also be used in combination with other therapeutic agents such as tissue grafts, tissue culture products, oxygen or dressings. The concentration of the peptide in the composition can be about 0.01 pg/mL to about 100 pg/mL, about 0.1 pg/mL to about 50 Jg/mL, and about 0.1 pg/mL to about 1 gg/mL. The composition can be administered to the wound topically. The animal can generally be any kind of animal, and preferably is a mammal, and more preferably is a human, cow, horse, cat, dog, pig, goat, or sheep. A preferred composition for wound healing applications in which ECM protein production is promoted comprises SEQ ID NO:8; more preferably, the composition comprises SEQ ID NO:8 in a heterogeneous mixture with at least one other tetrapeptide. In a most preferred embodiment, the individual tetrapeptides in the composition would cause sustained collagen production over a period of at least 48 hours. loozsj An additional embodiment of the invention is directed towards a method for reducing scarring of skin damaged by normal aging, disease, injury, trauma, or by surgery or other medical procedures. The method can comprise administering to the wound of an animal a composition, wherein the composition comprises any of the above-described peptides, singularly or in combination. The compositions can be a liquid, lotion, cream, paste, ointment, foam, or other pharmaceutically acceptable formulation. The compositions may contain pharmaceutically acceptable carriers or adjuvants. The compositions may contain other biologically active agents such as antimicrobial agents or growth factors. The compositions may also be used in combination with other therapeutic agents such as tissue grafts, tissue culture products, oxygen or dressings. The concentration of the peptide in the composition can be about 0.01 pg/mL to about 100 pig/mL, about 0.1 pg/mL to about 50 pg/mL, and about 0.1 pg/mL to about 1 pg/mL. The composition can be administered to the wound topically. The animal can generally be any kind of animal, and preferably is a mammal, and more preferably is a human, cow, horse, cat, dog, pig, goat, or sheep. A preferred composition for wound healing applications in which ECM protein production is promoted comprises SEQ ID NO:8; more preferably, the composition comprises SEQ ID NO:8 in a heterogeneous mixture with at least one other tetrapeptide. In a -7 most preferred embodiment, the individual tetrapeptides in the composition would cause sustained collagen production over a period of at least 48 hours. 100261 A further embodiment of the invention is directed towards a method for producing the disclosed tetrapeptides in combination. The peptides may be produced using any method known to those skilled in .the art such as those disclosed in Merrifield, R.B., Solid Phase Peptide Synthesis I., J. AM. CHEM. SOc. 85:2149-2154 (1963); Carpino, L.A. et al., [(9 Fluorenylmethyl)Qxy] Carbonyl (Fmoc) Amino Acid Chlorides: Synthesis, Characterization, And Application To The Rapid Synthesis Of Short Peptides, J. ORG. CHEM. 37:51:3732-3734; Merrifield, R.B. et al., Instrument For Automated Synthesis OfPeptides, ANAL. CHEM. 3 8:1905 1914 (1966); or Kent, S.S.H. et al., High Yield Chemical Synthesis Of Biologically Active Peptides On An Automated Peptide Synthesizer 0fNovel Design, IN: PEPTIDES 1984 (Ragnarsson U., ed.) Almqvist and Wiksell Int., Stockholm (Sweden), pp. 185-188, all of which are incorporated by reference herein in their entirety. Preferably, the peptides will be produced by a machine capable of sequential addition of amino acids to a growing peptide chain. However, the peptides may also be manufactured using standard solution phase methodology. [00271 It has been observed that the addition of a mixture of free amino acids instead of homogenous peptide mixtures during peptide chain synthesis results in varied incorporation of free amino acids such that a combination of peptides results from the synthesis reactions. The relative incorporation frequency of a particular amino acid included in a mixture of two or more amino acids added during synthesis may be adjusted. Adjustment is made possible by modifying the ratio of a free amino acid made available during the synthesis process relative to the other amino acids in the mixture (this is termed an isokinetic mixture). [00281 The following examples are included to demonstrate preferred embodiments of the invention. It should be appreciated by those of skill in the art that the techniques disclosed in the examples which follow represent techniques discovered by the inventor to function well in the practice of the invention, and thus can be considered to constitute preferred modes for its practice. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit and scope of the invention. EXAMPLES Example: Identification of repeat tetrapentide sequences in collagen 100291 A relatively high proportion of collagen IV tetrapeptide repeat sequences have the motif GxxG (where x is any amino acid). A number of these are shown in situ as part of the full collagen TV sequence illustrated in Figure 1 as SEQ ID NO:45. Collagen IV was examined first due to its role of interacting with other specialized ECM components (See Gregory Schultz et al., 2005). There are eleven sequences with the GxxG motif in collagen IV that appear more than ten times (GxxG where xx is represented by: vp, ek, fp, lp, pp, sp, ep, ip, pk, qp and tp). Of these tetrapeptide sequences, eight of eleven sequences contain proline in position 3, two of eleven sequences contain P in position 2, one of eleven sequences contains proline in positions 2 and 3, and one of eleven sequences contains no proline. The disclosed sequences are referred to as REPLIKINESTM. "REPLIKINE" is defined as a short sequence within ECM proteins that occurs multiple times (i.e., is replicated). This sequence may be present in one ECM protein (e.g., collagen IV). Preferably, the sequence is present in multiple ECM proteins (e.g., all collagens, elastin, laminin, etc.). The presence of the sequence in multiple ECM proteins increases the likelihood that the fragment may be able to promote ECM synthesis or repair. (ooo The eleven GxxG sequences appearing in collagen IV listed above are highlighted in the human collagen IV sequence illustrated in Figure 1. In this figure, all bold sequences are underlined and overlapping sequences are double-underlined. All but one of these sequences also appears in collagens I, II, III, and V. This fact contributes to the ability of the disclosed peptides to stimulate the production of all collagen types, particularly when the peptides are used in combination. Table I shows the frequency of several tetrapeptide repeats in ECM proteins. Bold sequences in Table 1 are those that appear in collagen IV ten or more times. Table 1: Frequency of tetrapeptides in ECM proteins SEQ. Sequenc Collagen Collagen Collagen Collagen Clagen Elastin ID NO e I II III IV V Elastin Precursor 19 GAAG 10 5 7 2 4 5 20 GAKG 3 4 3 5 5 21 GAPG 13 21 25 6 9 ' 22 GDKG 2 2 4 9 3 23 GDRG 2 5 2 4 1 8 GEKG 3 5 4 22 15 5 GEPG 11 15 10 11 4 24 GERG 10 11- 14 6 7 2 GFPG 4 8 6 22 5 1 1 25 GIPG 2 2 6 14 6 5 5 26 OKDG 1 4 5 2 2 27 GK.PG 2 3 3 4 1 -9 SEQ. Sequenc Collagen Collagen Collagen Collagen Collagen Elastin IDNO e I HI III IV V Elastin Precursor 28 GLKG 2 1 1 5 4 .29 GLPG 15 10 9 42 is 1 1 30 GNPG 3 5 3 2 1 31 OPAG 16 20 20 3 6 32 GPKG 3 11 4 12 9 7 GPPG 33 40 40 46 43 . 33 GPQG 7 11 9 7 5 34 OPRO 11 13 10 4 7 35 GPSG 10 11 5 1 5 36 GPTG 4 3 2 2 6 37 GPVG 9 3 3 2 5 38 GQPG 3 4 6 12 7' 3 GRDG 4 2 3 3 ~ 40 GRPG 3 3 4 2 5 3 GSPG 4 6 21 16 3 41 GTPG 3 4 2 11 2 42 GVKG 1 3 2 3 1 43 GVG 3 10 1 14 15 44 Y 1 1 1 4 I 100311 As also evident from a review of the collagen IV sequence, SEQ ID NO:45, there are also many occurrences of sequences having the PxxP motif. For example, the sequence PGPP occurs no less than fifteen times as illustrated in Figure 3. Therefore, this disclosed sequence is also referred to as a REPLIKINETM. Preferably, this sequence is present in multiple ECM proteins (e.g., all collagens, elastin, laminin, etc.) as the presence of this sequence in multiple ECM proteins increases the likelihood that the fragment may be able to promote ECM synthesis or repair. The fifteen PGPP sequences appearing in collagen IV listed above are highlighted and underlined in the human collagen IV sequence illustrated in Figure 3. Ex-ample 2: Identification of frame shift actives 100321 In addition to the relatively high proportion of collagen IV tetrapeptide repeat sequences with the motif GxxG, other tetrapeptide sequences occurring one amino acid frame shift away from a CxxQ or PxxP tetrapeptide sequence have been identified. These sequences may repeat or occur only once within an ECM protein and may be located one amino acid position away from either a QxxQ or PxxP tetrapeptide sequence as described herein. These tetrapeptide sequences are referred to as frame shift actives. Such frame shift actives may accordingly contain either a G or a P in either the second or third position depending on the direction of frame shift. It has been further recognized that frame shift actives may be combined with other -10 tetrapeptide sequences disclosed in this application forming a combikine. An example of such a combikine is H06 and HIS. 100331 One example of a frame shift active is GAGP or H12 (SEQ ID NO:6). H12 (GAGP) appears one residue (or frame) shift from the GxxG tetrapeptide GGAG in Collagen III (SEQ ID NO:46) as illustrated in Figure 2. In this figure, all frame shift active sequences are bold and underlined and the GxxG sequences occurring one frame shift away are double-underlined. Furthermore, as shown in Table 5, this tetrapeptide (GAGP) achieves good results for collagen production at 48 hours. Another example is the sequence PGPR, which is HIO (SEQ IM NO:4) which occurs eleven times in Collagens I-IV. As it appears multiple times in an individual ECM protein, this tetrapeptide would further be considered a REPLIKINE. Figure 2 (SEQ ID NO:46) illustrates several instances of this tetrapeptide with each occurring one frame shift from the GxxG tetrapeptide GPRG. This particular frame shift active appears in multiple ECM proteins and therefore increases the likelihood that the fragment may be able to promote ECM synthesis gr repair. Example 3: Identification of repeat sequences that stimulate collagen production 1oo341 Several sequences identified in Examples 1 and 2 were synthesized using standard peptide chemistry and assayed for the stimulation of collagen from dermal fibroblasts. The synthesized peptides were amidated at the C-terminus, which rendered the tetrapeptides less susceptible to protease degradation and increased their solubility compared to the free acid forms. Human dermal fibroblasts were incubated in 96-well plates at 37 *C and 5% COz for 24 and 48 hours in 150 pL complete cell culture media (Cascade Biologics, Portland, OR; Cat. No. M-106-500), supplemented with Low Serum Growth Supplement (Cascade Biologics, Portland, OR; Cat. No. S-003-10) containing sample peptides at a final peptide concentration of 50 pg/mL. Each well was seeded with 10,000 cells. Following the incubation, 100-jiL medium samples were recovered from each well and assayed for collagen production oo3sl The assays were performed by Tebu-bio Laboratories (France) using the SIRCOLr Collagen Assay Kit (Biocolor Assays, UK) following the manufacturer's protocol. The SIRCOLTm Collagen Assay is a quantitative dye-binding method designed for the analysis of soluble collagens released into culture medium by mammalian cells during in vitro culture. The collagen of the tested samples binds to the anionic SIRCOLTM dye. The collagen-dye complexes precipitate out of solution and are pelleted by centrifugation. The recovered collagen-dye pellet -11 -was dissolved in an alkaline solution prior to absorbance measurements. Duplicate measurements were taken at the 24 and 48 hour times from two separate samples. The four measurements for each sample were averaged. The absorbance of reagent blanks, collagen standards, and samples were measured at 560 nm. The reagent blank absorbance was subtracted from the absorbance from each sample at 24 and 48 hours. loo361 Two separate data sets were used to generate two collagen standard calibration curves. The first calibration curve was generated for purposes of calculating the quantity of collagen in samples H6 (combination of SEQ ID NOs:1-4), H7-H14 (SEQ ID NOs: 1-8, respectively) and H15 (combination of SEQ ID NOs:5-8). The second calibration curve was generated for calculating the quantity of collagen in samples H16 (SEQ ID NO:9), H21-23 (SEQ ID NOs:10 12, respectively), H25-26 (SEQ ID NOs:13-14, respectively), or H29-30 (SEQ ID NOs:15-16, respectively), H32 (SEQ ID NO:17), H33 (combination of SEQ ID NOs:9-12), H34 (combination of SEQ ID NOs:11-14), H35 (combination of SEQ ID NOs:13-16), H36 (combination of SEQ ID NQs:1, 6, 5, 8), H37 (SEQ ID NO:17) and H38 (SEQ ID NO:8) from the absorbance measurements was created by plotting the Abs 56 0o., of the known collagen standards versus the respective concentrations of the collagen standards (in micrograms) each time a series of assays were performed. With respect to each data set, the same calibration curve was used for samples taken at the 24 and 48 hour times (Tables 2A and 2B). Accordingly, different standard curves were prepared immediately prior to performing each series of assays. Table 2A: Calibration curve for assaying collagen production by peptides H6-H15 Collagen

A

5 0 nm 24h Ass 6 nm 48h standards test test 4 0.00 0.00 0.08 0.10 10 0.11 0.15 25 0.32 0.35 50 0.66 0.65 - 12 Table 2B: Calibration curve for assaying collagen production by peptides H16, H21-23, H25-26, and H29-38 Collagen Standards As 56 so.m Assay date 1 Assay date 2 0 0.00 0.00 5 0.12 Q.09 10 0.14 0.15 25 0.48 0.42 50 0.88 0.80 IOO37J A linear regression was performed from plotting the Abss.onm values versus concentrations of the respective collagen standards using MICROSOFT EXCELTM. The regression resulted in a lines described by the formula y = 0.01 3x for both incubation times noted in Table 2A. As the results were identical, only the 24-hour time period was used for the second series calibration curves. The formula of the line obtained on assay date 1 and assay date 2 of the second series of samples was y= 0.0178x and y = 0.0162x, respectively. The peptide LL-37 (SEQ ID NO: 18) was used as a positive control as it has been widely reported to have an impact upon wound healing in man (Heilbom et al., The Cathelicidin Anti-Microbial Peptide LL-37 Is Involved In The Re-Epithelialization Of Human Skin Wounds And Is Lacking In Chronic Ulcer Epithelium, J. Invest. Dermato. 120:379-89 (2003)). The assay detection limit defined by the manufacturer is 2.5 pg. 100381 The total amount of collagen produced in samples containing peptides was calculated frm the averaged absorbance values taken at 24 hours (Table 3A) and 48 hours (Table 3B) using the linear equation derived from the standard curve. The total amount of collagen produced in samples containing peptides H16 (SEQ ID NO:9), H21-23 (SEQ ID NOs:10-12, respectively), H25-26 (SEQ ID NOs:13-14, respectively), or H29-30 (SEQ ID NOs:15-16, respectively), H32 (SEQ ID NO:17), H33 (combination of SEQ ID NOs:9-12), H34 (combination of SEQ ID NOs:1l-14), H35 (combination of SEQ ID NOs:13-16), H36 (combination of SEQ ID NOs:1, 6, 5, 8), H37 (SEQ ID NO:17) and H38 (SEQ ID NO:8) was calculated from the absorbance values taken at 24 hours (Table 4A) and 48 hours (Table 4B) using the linear equation derived from the standard curve. These values were compared with peptide LL37 (SEQ ID NO:18), a peptide known to stimulate collagen. In each table, samples marked by an asterisk (*) may not be significant as the assay detection limit is 2.5 jg.

-13 Table 3A: Absorbance measurements and quantification of collagen in test samples 116 H15 at 24 hours. SEQ ID Peptides Asen. Average Average minus Collagen NO PetdsAomAeae blank Wp) 18 LL37 0.102 0.136 0.12' 0.04 3.0 - H'W6 0.084 0.140 0.11 0.03 2. 1 H7 0.098 0.063 0.08 0.00 0.0* 2 H8 0.122- 0.978 0.10 0.02 '1.5* 3 A9 0.147 0.104 0.13 0.05 3.5 4 H10 0.103 0.146 .12 0.04 3.4 5 HI1 0.110 0.168 0.14 0.06 4.5 '6 _ H12 0.063 0.101 0.08 0.00 0.2* 7 H13 '7'14 0.093 0.10 0.02 1.8* 8 H14 0.115 0.122 0.12 0.04 3.0 - HIS 0.132 0.093 0.11 0.03 2.5 - Blank 0.074 0.076 0.08 0.00 0.0 Table 3B: Absorbance measurements and quantification of collagen in test samples H6 H15 at 48 hours. SEQO Peptides As6o.. Average Average minus Collagen NO PpdeA 5 omArge blank OW~g 18 LL37 0.262 0.113 0.19 0.07 5.2 - H6 0.086 0.189 0.14 0.02 1.3* I H7 0.192 0.189 0.19 0.07 5.4 2 H8 0.137 0.126 0.13 0.01 0.9* 3 H9 0.117 0.061 0.09 0.00 0.0* 4 H10 0.136 0.085 0.11 0.00 0.0* 5 H 0.113 0.181 0.15 0.03 2,1* 6 H112 0.106 0.231 0.17 0.05 3.7 7 H13 0.100 0.145 0.12 0.00 0.2* 8 014 0.132 0.176 0.15 0.03 2.6 H15 0.177_ 0 0.174 0.18 0.06 4.3 Blank 0.120 0.115 0.12 0.00 0.0 Table 4A: Absorbance measurements and quantification of collagen in test samples H16, H21-23, H25-26, or H29-38 at 24 hours. SEQ ID Pptdes Assoam Average Average minus Collagen NO blank (pig) 9 H16 0.1'33 0.137 0.14 0.06- 3.1 10 H21 0.129 0.119 0.12 0.04 2.5 11 ' H22 0.92 0.085 0.14 0.06 3.3 12 H23 0.090 0.073 0.08 0.00 0.1* 13 125 0.129 0.076 0.10 0.02 1.3* - 14 SEQ ID Average minus Collagen NO Peptides Average blank (sg) 14 H26 0.114 0.149 0.13 0.05 2.9 15 H29 0.111 0.063 0.09 0.01 0.4* 16 H30 0.099 0.092 0.10 0.02 0.9* 17 H32 (crystals 0.087 0.055 0.07 -0.01 -0.5* and cell toxicity) - H33 0.086 0.125 0.11 0.03 1.4* - I-4 0.117 0.120 0.12 0.04 _ .2 * - H35 0.103 0.090 0.10 0.02 0.9* - H3'6 0.105 0.1'28 0.12 0.04 2.1* 17 H37 0.099 0.100 0.10 0.02 1.1* 8 H38 0.103 0.159 0.13 0.05 2.9 - Blank 0.072 0.086 0.08 0.00 0.0 Table 4B: Absorbance measurements and quantification of collagen In test samples H16, H21-23, H25-26, or H29-38 at 48 hours. SEQ Peptides Asogm Average Avorage minus Collagen NO tds ~ mAvrg blank (jig) 9 H16 0.065 0.064 0.06 0.00 0.3* 10 H21 0.089 0.126 0.11 0.05 2.9 11 H22 0.162 0.087 0.09 0.03 2.1* 12 H23 0.093 0.082 0.09 0.03 1.7* 13 H2S 0.059 0.084 0.07 0.01 0.7* 14 H26 0.081 0.153 0.12 0.06 3.5 15 H29 0.086 0.094 0.09 0.03 1.9* 16 H30 0.083 0.101 0.09 0.03 2.0* 17 H32 (crystals 0.088 0.072 0.08 0.02 1.2* and cell toxicity) - H33 0.096 0.092 0.09 0.03 2.1* - H34 0.076 0.155 0.12 0.06 3.4 - H35 0.120 0.074 0.10 0.04 2.3* - H36 0.154 0.082 0.12 0.06 3.6 17 H37 0.078 0.114 0.10 0.04 2.2' 8 H38 0.123 0.089 0.11 0.05 2.8 - Blank 0.106 0.0106 0.06 0.00 0.0 100391 Because sample sizes were 100 pL, the concentration of collagen produced in each sample in micrograms per milliliter is determined by multiplying the amount of collagen detected by ten. The results of all samples tested are summarized in Table 5.

-15 Table 5: Collagen synthesis induced by peptides Collagen produced SEQ Piiay[Peptidje 24 A 48 ID NO Name Primary sequence mL 24rs 48hrs I H07 PEGP 50 0 54 2 H08 GFPG 50 15 9 3 H09 GSPG 50 35 0 4 H1O PGPR 50 34 0 - H7,H8,H9,H10 (SEQIDN0s:1,2,3, H06 4) 50 25 13 5 H11 GEPG 50 45 21 6 H12 GAOP 50 2 37 7 H13 GPPG 50 18 2 8 H14 GEKG 50 30 26 8 H38 GEKG 0.3 29 28 - H11,H12,H13,1114 (SEQIDNOs:5, HIS 6,7,8) 50 25 43 9 H16 PEKP 50 31 3 10 H21 PKGP 50 25 29 11 H22 PGQP 50 33 21 12 H423 P9TP 50 1 17 13 H25 PMGP 50 13 7 14 H26 PGPP 50 29 35 15 H19. PQGP 50 4 19 16 H30 PGNP 50 9 20 17 H132 KITKS (SEDERMA- peptide) 50 na 12 17 H37 KTTKS (SEDERMAm peptide) 0.3 11 22 - H16, H21, H22, H23 (SEQ ID NOs:9, H33 10, 11, 12) 50 14 21 - H22, HX3, H25, H26 (SEQ ID NOs: 11, H34 12, 13, 14) 50 22 34 - H25, H26,H29, H30 (SEQ ID NOs:13, H35 14, 15, 16) 50 9 23 - H, H12, H11, H 14 (SEQ ID NOs:1, 6, H36 5,8) 50 21 36 18 LLGDFFRKSKEKIGKEFKUVQRID LL37 FLRNLVPRTES 50 30 52 100401 All tetrapeptides tested stimulated the production of soluble collagen. Of the sequences tested, OxxG tetrapeptides with a glutamic acid in position 2 best stimulate collagen at both 24 and 48 hour time-points. These sequences are Hi1 (GEPG; SEQ ID NO:5), H14 (GEKG; SEQ ID NQ:8) and H38 (GEKG; SEQ ID NO:8). The peptides were initially screened using a peptide concentration of 50 pg/mL. To survey the. concentration effective for stimulating collagen production, H14 ($EQ ID NO:8) was also tested at 0.3 pg/mL as H38. As shown in Table 5, -16 H38-induced collagen stimulation was not diminished at the lower concentration, indicating that the maximal stimulating concentration of SEQ ID NO:8 is at or below 0.3 pgImL. 10041 To test its efficacy, SEQ ID NO:8 (H14 and H38) was compared to the peptide, LL37, (SF,Q ID NO:18) which is known to stimulate collagen production. Based on the amount of collagen released by fibroblasts in response to LL37, 25 pg/mL was considered a significant amount of collagen released due to contact with a tetrapeptide. SEQ ID NO:8 induced about the same amount of collagen as LL37 (SEQ ID NO: 18) at 24 hours. Importantly, collagen produced as a result of contact with SEQ ID NO:8 was substantially maintained for at least 48 hours. SEQ ID NO:8 was also compared to a leading skin care peptide known to stimulate collagen production, KTTKS (SEQ ID NO:17) (Katayama et. al., J. BIOL. CHEM. 288:9941-9944 (1983)). KTTKS is an ingredient in the product MATRIXYLTm (SEDERMA SAS, France). SEQ ID NO:8 stimulated more collagen production than the KTTKS (SEQ ID NO:17) peptide (Table 5) at 24 and 48 hours. Example 4: Identification of Deptide combinations that synergistically enhance collagen stimulation - COMBIINES 10D421 Heterogeneous populations of active tetrapeptides may stimulate collagen production at a higher level than homogenous samples of tetrapeptides. The components of the heterogeneous composition are called COMBIKINESTM. COMBIKINES are a group of REPLIKINES combined to produce a greater or broader effect upon one or more target cell types. The peptides HI I (SEQ ID NO:5), H12 (SEQ ID NO:6), H13 (SEQ ID NO:7), and H14 (SEQ ID NO:8) were combined to a final concentration of 50 jig/mL and assayed using the same protocol as for the individual peptides. As expected, the result obtained at the 24 hour time point equaled the mean of the individual induction scores. The combination of peptides at 48 hours, however, induced collagen to a level of 43 pg/mL. Surprisingly, this amount was far in excess of the anticipated mean (21 pg/mL) of the four individual peptides (see Table 5). Thus, specific combinations of peptides may stimulate collagen production to a greater degree than the individual peptides at the same concentration. Further, tetrapeptides from a variety of ECM sources such as collagen, laminin, and elastin may produce enhanced induction of a variety of ECM proteins (see Tables I and 5). Example 5: Cost-effective COMBIKINE manufacturing for enhancing stimulation of collagen production -17 1oi The high cost of peptide synthesis limits the feasibility of producing of heterogeneous compositions of bioactive peptides. The present invention greatly mitigates this limitation. Because the presently disclosed sequences have a commonality (e.g., a glycine or proline at both termini), a range of tetrapeptides varied at positions 2 and 3 can be synthesized in a single manufacturing run. The synthetic peptides can be made by any method known in the art. (Benoiton, N., Chemistry of Peptide Synthesis, CRC (2005)). During manufacture of the peptides, amino acid mixtures are added instead of homogenous samples. The chemistry for determining the correct ratios of amino acid concentrations added at the mixed positions to gain the desired ratio of resulting peptides has been described previously (Greenbaum et al., Molecular and Cellular Proteomics 1:60-68, 2002; Krstenansky et al., Letters in Drug Design and Discovery 1:6-13, 2004; both of which references are incorporated herein in their entirety). Using this methodology, a library of heterogeneous peptides can be made for nearly the same cost of synthesizing one peptide. loom The application of this manufacturing process enables the cost-effective production of bioactive combikines. This is made possible by the unique composition of the disclosed tetrapeptides. The tetrapeptide mixtures are better suited for incorporation into topical use formulations than longer peptides. Because of their length, tetrapeptides have practical and chemical advantages over longer peptides, including the following: easier incorporation and dissolution into formulations, higher skin and pore permeability, and higher production yields with easier methods of manufacturing combinations of peptides. Although not required, the ideal formulations of tetrapeptides, singly or in combination, are formulations that maintain significant collagen production at 24 hours for up to 48 hours. More preferably, the formulations would induce synthesis of ECM for the .entire 48 hour period such that more collagen is produced by 48 hours than at 24 hours. Although within the scope of the current invention, tetrapeptides that promote production of ECM proteins at 24 hours, but show diminished production at 48 hours, are less favored. In this regard, Table 6 shows the results of the currently disclosed peptides. Preferred peptides are in bold.

- 18 Table 6: Disclosed peptides Released Released Significant Increase Decrease SEQ ID collagen collagen release in collagen in collagen NO Peptides (pg/mL) (pg/mL) of collagen release release 24h 48h at 24h and 48h at 48h v. 24h at 48h v. 24h 18 LL37 30 52 _______ - M6 25 13 I H7 0 54 _ _ 2 H18 is 9 _____ 3 H9 35 0 4 HIO 34 0 1 Hl1 45 21 _ 6 H12 2 37 7 H13 18 2 8 i114 30 26 _____ 8 1138 29 28 .4____ - H21 2S 43 9 _6 3 1 3 _ 10 Bill 25 29 ______ ______ I1I H22 33 21 ______ _____ 12 H23 1 17 ______ 13 1125 13 7_____ 14 H26 29 35 _ 15 H29 4 19 16 H30 9 20 17 H32 (crystals NA 12 and cell toxicity) 17 H37 11 22 - H33 14 21 - H34 22 34 - H35 9 23 - H36 21 36 Example 6: Collagen stimulators also serve as multi-effector molecules enhancing skin epithelial cell wound closer 100451 Collagens are key components of all phases of wound healing. Stimulation of collagen production reflects that damage has occurred to the collagen network (e.g. by enzymes or physical destruction). Indeed, the total collapse of the collagen network in fact causes healing to take place. Therefore a collagen stimulator may also serve as a multi-effector molecule orchestrating certain matrix remodeling and enhancing wound healing.

- 19 1ee461 Wound healing experiments were performed on monolayers of human skin epithelial cells (CRL-2592) plated onto 12-well plates. Cells were serum-starved for 24 hours before experimentation. Confluent monolayers of CRL-2592 were wounded using a P200 (200-pL) pipette tip. The wounds were washed and picture-documented prior to peptide treatment. Peptides were added to a final concentration from 20 to 40 pg/ml. Cells were kept in an incubator at 37*C, 5% C0 2 , and 92% humidity, except when images were being captured for a short period at room temperature. Wound closure was followed at 6-hour and 10-hour time points. PBS-treated wounds were used as negative controls for comparison purposes. Table 7: Effect of peptides on human skin epithelial wound closure in vitro Ohr 6hr 10hr Compound W-size* W-slze % closure W-size % closure PBS-1 36 29 19.40% 21 41.70% PBS-2 52 42 19.20% 30 42.30% SEQ ID NO:14 25 12 52% 2.75 89% SEQ ID NO:5 48 39 19% 30 37.50% * W-size: wound size (arbitrary) 100471 In vitro monolayer wound closure is a result of cell migration, which is important in many biological processes such as embryogenesis, angiogenesis, inflammatory reactions and wound repair. These processes are thought to be regulated by interactions with other cells, cytokines and ECM proteins. As shown in Table 7, SEQ ID NO:14 significantly induces wound closure compared to the effects of PBS alone. Such activity is peptide-specific as well as cell type-specific since SEQ ID NO:14 does not induce wound closure in a human skin fibroblast monolayer (data not shown). SEQ ID NO:5 is also a collagen inducer, but does not enhance wound closure or epithelial cell migration to any great extent compared to the effects of PBS alone. The fact that SEQ ID NO;14 induced cell migration or wound closure in a manner specific to skin epithelial cells (i.e. does not recruit fibroblasts) may add an advantage to using this peptide for skin care, since it is believed that the recruitment of large numbers of active fibroblasts to a wound site results in excess deposition and contraction of tissue resulting in scarring.

-20 100481 All of the compositions or methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the compositions and methods of this invention have been described in terms of preferred embodiments, it will be apparent to those of skill in the art that variations may be applied to the compositions and/or methods and in the steps or in the sequence of steps of the methods described herein without departing from the concept, spirit and scope of the invention. More specifically, it will be apparent that certain agents which are both chemically and physiologically related may be substituted for the agents described herein while the same or similar results would be achieved. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and concept of the invention. 100491 With reference to the use of the word(s) "comprise" or "comprises" or "comprising" in the foregoing description and/or in the following claims, unless the context requires otherwise, those words are used on the basis and clear understanding that they are to be interpreted inclusively, rather than exclusively, and that each of those words is to be so interpreted in construing the foregoing description and/or the following claims.

Claims (15)

1. A tetrapeptide of the formula PxxP capable of inducing the production of an extracellular matrix protein wherein the tetrapeptide comprises SEQ ID NO: 9 (PEKP), SEQ ID NO: 10 (PKGP), SEQ ID NO: 11 (PGQP), SEQ ID NO: 12 (PGTP) or SEQ ID NO: 16 (PONP).

2. A tetrapeptide of the formula PxxP capable of inducing the production of an extracellular matrix protein wherein the tetrapeptide comprises SEQ ID NO: 1 (PEGP), SEQ ID NO: 14 (PGPP), SEQ ID NO: 9 (PEKP), SEQ ID NO: 10 (PKGP), SEQ ID NO: 11 (PGQP), SEQ ID NO: 12 (PGTP), SEQ ID NO: 13 (PMGP), SEQ ID NO: 15 (PQGP) or SEQ ID NO: 16 (PGNP) when used in the manufacture of a medicament or cosmetic useful for treating damaged skin or maintaining healthy skin.

3. The tetrapeptide of any one of claims 1 or 2, wherein the tetrapeptide is amidated at the carboxy-terminus.

4. A medicament or cosmetic composition useful for treating damaged skin or maintaining healthy skin comprising a tetrapeptide according to any one of claims 1 to 3, and a pharmaceutically or cosmetically acceptable carrier.

5. The composition of claim 4, wherein the tetrapeptide is present in an effective concentration ranging from about 0.01 tg/mL to about 100 pg/mL.

6. The composition of claim 4, wherein the composition is in the form of an aerosol, emulsion, liquid, lotion, cream, paste, ointment, or foam.

7. A composition comprising a mixture of the tetrapeptides: a) SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID NO: 11 and SEQ ID NO: 12 b) SEQ ID NO: 11, SEQ ID NO: 12, SEQ ID NO: 13 and SEQ ID NO: 14; or c) SEQ ID NO: 13, SEQ ID NO: 14, SEQ TD NO: 15 and SEQ ID NO: 16. -22

8, The composition of claim 7, wherein the composition is in the form of an aerosol, emulsion, liquid, lotion, cream, paste, ointment, or foam.

9. The composition of any one of claims 4 to 8 for use in skin care.

10. The composition of claim 9, wherein said skin care addresses skin wrinkling, toning, firming and sagging.

11. The composition of any one of claims 4 to 8, wherein the tetrapeptide is useful to stimulate collagen production when applied to the skin.

12. The composition of any one of claims 4 to 8 for use in treatment of a skin wound.

13, The composition of claim 12, wherein said skin wound is a result of aging, disease, injury, trauma, or surgery.

14. A method for stimulating the production of collagen by a cell, the method comprising exposing a cell to a tetrapeptide according to any one of claims 1 to 3, or mixture thereof, thereby inducing collagen production by the cell.

15. The method of claim 14, wherein the cell is a fibroblast cell. [3A,97SIB