FR2719846A1 - Sulphated galactan oligosaccharide(s) - Google Patents

Abstract

Sulphated galactan oligosaccharide (I) having 2-20 saccharide units and a sulphation level of \-0.5 sulphate gp./saccharide unit, is new. Also claimed are:(a) a mixt. of (I) characterised in that \-50% by wt. is (I);(b) a compsn. for topical external application which contains (I) as the principle active ingredient, and an appropriate support;(c) cosmetic and pharmaceutical compsns. as in (b), and(d) a cell culture additive contg. (I).

Description

 The subject of the invention is oligosaccharides of sulfated galactans with external topical activity on the skin as a cosmetic and pharmaceutical active principle.

 Sulfated galactans, which include carrageenans and agars in particular, are well known for their gelling and / or thickening properties.

 The applicant company has demonstrated that certain sulfated galactan oligosaccharides make it possible to activate the proliferation of keratinocytes and are capable of stimulating the contractile power of fibroblasts.

 As a result, the sulfated galactan oligosaccharides which will be described below have a regenerating dermal and epidermal effect and in particular make it possible to improve the elasticity of the skin and to promote the phenomenon of wound healing.

 The sulfated galactan oligosaccharides therefore find use in the field of medical and cosmetic applications as, in particular, as a product for external topical use.

 Other applications as a medicament can also be envisaged, taking into account the remarkable properties of these fragments.

 The sulfated galactan oligosaccharides also find application as cell culture additives.

 The invention relates primarily to oligosaccharides of sulfated galactans comprising from 2 to 20 saccharide units and having an average sulfation rate of at least 0.5 sulfate per saccharide unit.

 The family of galactans includes in particular agars and carrageenans.

Carrageenans are sulfated polysaccharides extracted from red algae, such as those of the type belonging to the orders of
Gigartinales, Ahnfeltiales, and in particular the species Eucheuma sp., Chondrus crispus and Gigartina sp., Hypnea sp.

 Although there are different kinds of carrageenans which are slightly different from each other, there is always a common skeleton which is a chain of D-galactoses linked alternately in a- (1 3) and Fur (1 - 4). The differences between the carrageenans are due to the quantity and the position of the sulfates as well as to the presence or not of an anhydro 3,6 bridge on the galactose linked in 1 and 4.

We mainly distinguish the following carrageenans 1 / Kappa carrageenan. formed by a succession of 1,3-BD
galactopyranose 1,4 sulfate, conformation C1 "KgA unit" and 1,4-aD 3-6
anhydro galactopyranose, 1C conformation "Ka unit".

2 / Lambda carrageenan: Alternate sequence of 1,3-BD galactopyranose 2
sulfate, conformation C1 "Lg2 unit" and 1.4 D galactopyranose 2-6
disulfate conformation C1 "unit Lg 2.6".

3 / Iota carrageenan: Succession of D galactopyranose 4 sulfate,
conformation Cl "IgA unit" and 1,4- α D 3-6 anhydrogalactopyranose 2
sulfate conformation 1C "Ia2 unit".

There are also two biological precursors of
carrageenans mentioned above: 4 / Mu carrageenan: Succession of 1,3-ssD galactopyranose 4 sulfate,
conformation C1 "MgA unit" and 1,4 D galactopyranose 6 sulfate
conformation C1 "unit Nlg6".

Under the action of an enzyme in the algae or in an alkaline medium
Mg6 b Ka: Mu carrageenan is the precursor of Kappa
carrageenan.

5 / Carrageenan nude: Succession of 1,3-BD galactopyranose 4 sulfate,
conformation C1 "unit Ng4" and 1,4- D galactopyranose 2-6 sulfate
conformation C1 "unit Ng2,6"
Under the action of an enzyme present in the alga or in the middle
alkaline:
Ng2,6 Ia2: the Carrageenan Nude is the precursor of the Carrageenan Iota.

Agar-type galactans are formed from a polymer group
whose basic skeleton is a 1,3-ssD galactopyranose chain and l, 4a L 3-6
anhydrogalactose. These units repeating regularly and alternately.

The differences within the agar family are due to the presence or
not of sulfated, methylated or carboxyethylated groups. These h-flange structures
are generally present in variable percentages depending on the species
algae, harvest season. The agars according to the invention have at least (?, 5
sulfate equivalent per mole of saccharide.

In the case of Kappa type carrageenans, the tau de
sulfation is 0.5 sulfate equivalent / mole of saccharide and in the case of
Iota carrageenans, the sulfation rate is 1 sulfate equivalent / mole of
saccharide.

 In the case of agar-type galactans from which the oligosaccharides according to the invention come, the degree of sulfation varies from 0.5 equivalent sulfate / mole of saccharide to 3 sulfate / mole.

 The chemical terminations of the oligosaccharides according to the invention are different according to the process which has made it possible to obtain them by hydrolysis of the corresponding polysaccharides.

It is known in fact that there are two main types of depolymerization process for polysaccharides leading to the oligosaccharides according to the invention
Bellion et al., Described the enzymatic depolymerization of carrageenans from Eucheuma spinosum and Eucheuma Cottonii using iota-carrageenases and kappa-carrageenases from marine bacteria (Can.

J. Microbiol. 28 (7), 874-80. These authors have shown that the enzymatic hydrolysis takes place at the level of the fr (F 4) bond and the oligomers therefore have the termination:

Chemical hydrolysis has in particular been studied by Stortz et al.,
Carbohydr. Res., 166 (1987), 317-23, Stevenson et al., Carbohydr. Res. 210 (1991) 277-298 and USOV Hydrobiologia 260/261 (1993) 641-645. and it is likely that the chemical hydrolysis acts by the bond 1 3.

 The studies carried out by the applicant company show that the sulfated galactan oligosaccharides according to the invention, whether obtained by chemical or enzymatic depolymerization, exhibit remarkable activity, and consequently, the invention is not limited to oligosaccharides of sulfated galactans having a particular termination.

 The terminations can be anhydrogalactose-2-sulfate, and more precisely anhydrogalactitol-2-sulfate (chemical hydrolysis) or galactose-4 sulfate (enzymatic hydrolysis).

 The weight of a saccharide molecule is approximately 250, which weight can vary depending on the degree of sulfation of the polysaccharide. Thus, in the case of sulfated galactan oligosaccharides having 2 to 20 saccharide units, the average weight of a saccharide unit being approximately 250, the molar mass is between approximately 500 and 5000.

 It has been found that it is very advantageous, owing to their remarkable biological properties with respect to the skin, to use sulfated galactan oligosaccharides having 2 to 10 saccharide units.

 Preferably also, the sulfated galactan oligosaccharides have an average sulfation rate of at least 0.7 sulfate per saccharide unit when they are in the form of a mixture.

A list of oligosaccharides according to the present invention is given below which is of remarkable interest in the context of application by external topical route:
(Ig4 - Ia2) nn = 1 to 5, preferably 2 2
(IgA - Ia2) 2
(Ig - Ia2) 3
(Kg4 - Ka2), n = 1 to 5, preferably 2 2
(Kg4 - Ka2) 2
(Kg4 - Ka2) 3.

 According to a preferred embodiment, the sulfated galactan fragments according to the invention come from carrageenans and more preferably from iota-carrageenan.

 The subject of the invention is also, according to a particular variant taken or not in combination with one or more of the variants mentioned above, oligosaccharides of sulfated galactans such that they can be obtained by chemical or enzymatic depolymerization of carrageenan or agar , preferably iota carrageenan.

 As mentioned above, there are two main processes for hydrolyzing carrageenans or agars, namely chemical processes and enzymatic processes.

 In general, the enzymatic process consists in depolymenating in the presence of a suitable carrageenan or agarase as described for example by Bellion et al. (1982). In the case of the iotacarraghenase described by Bellion, the enzyme does not support freeze-drying or freezing (Greer et al., Can.J. blicrobiol. 30 (12) 1500-6 (1984). molar mass which is 57,000, its maximum activity is at pH 8 and at 40 C. The major products of the hydrolysis of iota-carrageenan consist of the oligosaccharides of sulfated galactans having 4 to 6 saccharide units. for the controlled depolymerization of carrageenan, a concern of which must be to avoid the formation of oligosaccharides of very low degree of polymerization (1 to 2 saccharide units).

We also know how to purify kappa-carrageenases from a mixture of extra-cellular carrageenases produced by the bacteria
Cytophaga species, Sarwar et al., Nlicrobiol. Immunol., 31 (9), 869-77 (1987) and
Potin et al., Eur. J. Biochem., 201 (1), 241-7 (1991). The enzyme studied in the latter case is a kappa-carrageenase produced by a bacteria close to the genus Cytophaga, but not identified so far. This enzyme is not thermostable (denaturation at 40-C). Its molar mass is 40,000. It produces kappa-neocarratetraose sulfate and kappa-neocarrahexaose sulfate unlike the kappa-carrageenan of Pseudomonas carrageenovora which mainly produces neocarrabiosis sulfate.

 This Cytophaga strain was isolated from a decaying alga, on a medium solidified with iota-carrageenan. If the strain is grown in the presence of agar, an agarase is excreted in the fermentation medium.

The production of carrageenan oligosaccharides by the enzymatic route generally comprises the following stages
- Carrageenan production by fermentation of a microorganism,
- Depolymerization of carrageenan by carrageenan,
- Extraction and purification of the oligosaccharides obtained.

 By way of example, the hydrolyses described by Potin et al. (1991) were carried out in the presence of 0.2 U of carrageenase per mg of polysaccharide for 6 h. Under these conditions, it takes approximately 200,000 U of carrageenan to hydrolyze 1 kg of carrageenan.

 The extraction and purification of the sulfated galactan oligosaccharides obtained are carried out in known manner by hydroalcoholic extraction or by chromatography.

In the case of sulfated galactan oligosaccharides obtained from agars, an agarase suitable for depolymerizing the polysaccharide is brought into contact according to the procedure indicated above, as described by Bhattacharjee et al. nostril Algae in Pharmaceutical Sciences ed. by
Hoppe, Levant, Tanaka, Walter de Gruyter - Berlin and New York p. 645-655 (1979).

According to another variant of the invention, the sulfated galactan fragments are such that they stimulate in vitro the contraction of equivalent dermes, caused by fibroblasts, at the appropriate doses when they are used in the following test
The fibroblasts distributed uniformly in a three-dimensional collagen matrix contract the matrix network. A gradual reduction in the diameter of artificial dermis is observed. The contractile power of fibroblasts is evaluated by daily measurement of the area occupied by the dermes using an image analyzer.

 According to the invention, the sulfated galactan oligosaccharides are such that they cause an increase in the contractile power of fibroblasts of at least 10%, preferably at least 20% for an appropriate amount, in particular of 100 crg / ml relative to the control which does not contain an oligosaccharide.

 In addition, according to a particularly preferred variant of the invention, the sulfated oligosaccharides partially lift the inhibition of fibroblast contraction caused by the presence of hydrocortisone, a compound well known for slowing tissue healing in vivo. The inhibition lift is improved by at least 10% after two days at the appropriate doses, preferably at least 20%, compared with the control treated with hydrocortisone.

 The sulfated galactan oligosaccharides according to the invention are also remarkable in that they activate the in vitro proliferation of keratinocytes.

 The invention also relates to mixtures of sulfated galactan oligosaccharides containing at least 30% by weight, preferably at least 50% by weight, of sulfated galactan oligosaccharides according to the invention.

 Advantageously, these mixtures contain 60% by weight of the sulfated galactan oligosaccharides according to the invention.

 The subject of the invention is also oligosaccharides of sulphated galactans or mixtures of oligosaccharides of sulphated galactans as they have been described previously as an active principle for their application as dermal and epidermal regenerant and as healing agent.

 These sulfated galactan oligosaccharides are applied in the form of a composition for external topical use containing said active principle and an appropriate support.

 The invention relates in particular to the pharmaceutical application of the sulfated galactan oligosaccharides according to the invention and more particularly to a pharmaceutical composition for external topical use, in particular for regenerating the dermis and the epidermis, containing a sulfated galactan oligosaccharide according to the invention and an inert support.

 The invention also relates to the cosmetic application of the sulfated galactan oligosaccharides according to the invention and more particularly to a cosmetic composition for external topical use, in particular for regenerating the dermis and the epidermis containing a galactan oligosaccharide according to the invention and a support. inert.

 The sulfated galactan oligosaccharides will be in pharmaceutical or cosmetic compositions in sufficient quantity so that the compositions applied to the skin provide a positive effect on the dermis and the epidermis, as regards scarring, elasticity, and usually regeneration of the skin.

 These compositions are for example solutions of lotion type, emulsions of liquid or semi-liquid consistency of milk type, obtained by dispersion of a fatty phase in an aqueous phase or vice versa or of suspension or emulsion of soft consistency of the cream type or gel. These compositions are prepared according to the usual methods.

Among the vehicles commonly used in the formulations for the skin mentioned above, mention may be made of surfactants. dyes, perfumes, preservatives, emulsifiers, liquid vehicles such as water, fatty substances such as natural or synthetic oils intended to constitute the fatty phase of milks or creams,
resins of the carboxylvinyl or maleic anhydride type neutralized by tertiary formulas and in particular by amino alcohols such as acrylethanolamine.

 The invention also relates to the use of the sulfated galactan oligosaccharides according to the invention or a mixture of galactan oligosaccharides as active principle for the preparation of compositions intended to promote the regeneration of the dermis.

 This use relates in particular to the preparation of compositions intended to accelerate the healing process.

Uses of galactan oligosaccharides according to
the invention are in the form of especially cosmetic compositions or
pharmaceuticals for external topical use.

The invention finally relates to an additive for cell culture.
consisting of sulfated galactan oligosaccharides according to the invention.

The invention is now illustrated by the following examples
given for information only, without in any way limiting the scope of the invention.

EXAMPLE 1 Prevalation of Olinosaccharides 1. Production of Carrageenan
The marine bacterium ATCC 43554 was cultivated in a 15 liter fermenter in the ATCC n 1576 saline medium containing 25 g / l of sodium chloride, 2.5 g / l of casein peptone and 2.5 g / l of iota- carrageenan. The medium was inoculated with 0.3 l of an Erlenmeyer flask culture
(proportion of innoculum: 2%). The turbidity of the medium increases during fermentation from 0.0 to 0.4 (absorbance at 600 nm of the medium diluted to 1/10). The temperature is maintained at 22 ° C, the pH remains between 7.2 and 6.8 during the fermentation, which lasts 8 hours.

 After fermentation, the medium was centrifuged (7,500 rpm, 20 min), then concentrated by ultrafiltration (cutoff threshold: 10,000) and diafiltered using sodium phosphate buffer pH 8, 25 mbI containing NaCl 0 , 1 IF. The final volume of the carrageenan preparation was 1 liter.

 This preparation contains 15,000 U of iota carrageenase and 300 mg of protein (activity determined by dosing the reducing sugars using ferricyanide and measuring absorbance at 267 nm).

2. Hydrolysis of iota-carrageenase
The iota-carrageenase hydrolysis reaction was carried out at pH
8, 40C in the following medium:
volume 1.21
- Iota-carrageenan 10 g
- Carrageenan solution 0.6 1
- NaCl 0.1 NI
- Sodium phosphate buffer pH8 50 mol.

The reaction was continued for 100 hours. The power
reducer (DNS dosage) varies from 0.1 to 0.4 g / l (glucose equivalent). The
polysaccharides were then precipitated using 66% ethanol (v / v). The precipitate was redissolved in water and subjected again to hydrolysis
(volume: 0.8 1) using 0.3 1 of carrageenase solution.

Then, this solution was also treated by precipitation at
ethanol. The centrifugation supernatants were then concentrated under reduced pressure, which made it possible to obtain the oligosaccharides in solution.
aqueous (volume 200 ml).

3. Purification of oligocarraghenans
The solution was diluted (1/2), then acidified to pH 2.5 and placed in the
contact of activated carbon (2.5 g / l), then filtered on paper and membrane
porosity 0.2 rm. It was applied to a column of Sephadex G 10 (volume
1 1) in fractions of 100 ml. The eluent is hydrochloric acid (pH 2.5).

 The elution lasts 4 hours. The oligosaccharides are eluted before the salts.

 The fractions containing the oligosaccharides were mixed and the pH was adjusted to 6 with sodium hydroxide. The solution thus obtained was ultrafiltered on a membrane with a cutoff threshold of 10,000, then concentrated under reduced pressure, filtered through a membrane with a porosity of 0.2 μm and finally lyophilized.

4. Characterization of the preparation of oliyocarrarhenans
The lyophilisate obtained has a mass of 6.1 g and is in the form of a beige powder. The powder was characterized by HPLC, by
colorimetric assays, and by physicochemical measurements, the results of which are given below
Water content 10%
(Karl Fischer)
e Properties of an aqueous solution
pH (50 g / l) 5.7
conductivity (5 g / l) 2.3 mS / cm
water solubility h 10 g / I
(opalescent solution)
Chloride content 3%
(Sigma colorimetric assay)
Chemical composition: - Total oligocarraghenans: 55%
of which: - oligocarraghénane tetrasaccharide 36%
- oligocarraghenane hexasaccharide 18%
- 1% oligocarraghenane octasaccharide - Sodium chloride: 35% - Water: 10% Microbiological analysis total terms): s 200 / g Example 2: Biological activity on keratinocyte
This study was performed with concentrations
of oligosaccharides obtained according to Example 1 of 10, 25 and 50 Fg / ml.

Cell profit is assessed by the number of cells
alive at the end of the test, evaluated by a colorimetric test at MTT
(cell viability test based on the activity of succinyldeshydrogenase
mitrochondrial).

Experimental protocol
Human keratinocytes, again from foreskin skin
born, are grown in serum-free culture medium (KGM + 0.4% BPE,
Clonetics) in humid air - CO2 (95% - 5%) at 37OC in vials
75 cm2 (NUNC).

Before reaching confluence, the cells are detached from their
support by trypsinization and suspended in KGM medium
(Keratinocyte Growth Medium) supplemented with BP (Bovine Pituitary Extract).

 After counting in the Nialassez cell, the cell suspension is diluted so as to seed approximately 10,000 cells per well in each well of a microplate (D-1).

24 hours after sowing, the culture medium is eliminated
and replaced either with new medium (control batch) or with medium containing the product under study (treated batches). 4 concentrations were studied: 10, 25, 50
and 100 Fg / ml.

In parallel with the microplate processing, the revelation of a plate inoculated with the same cell suspension on D-1 is carried out at
using an MTT test to determine the cell concentration at OJ
(start of treatment), taking into account the linear relationship between the
measured optical density and the number of cells seeded.

The microplates, once treated, are replaced in the oven at 37sC
in the presence of 5% CO2.

 Cell density is evaluated by an MTT test on D1, D3 and D6.

Results
Determination of the curve DO = f (N)
To verify the linear relationship between optical density (OD)
obtained by the MTT test and the number of cells, a 96-well microplate was seeded with different cell densities (1 column of 8 wells per cell density). The optical density increases in proportion to the number of cells seeded. An NlTT test was carried out 24 hours after sowing.

 There is a linear relationship between optical density and the number of cells per well.

Inv log DO = 0.0766 (NS 1 () 3) +0.546
r = 0.988 dof = 3
Droliferative Activity
At D1, the cell densities at the level of the treated batches are substantially identical to that of the control batch.

 On D3, a very slight stimulating effect is observed in the batches treated with 25 rg / ml.

 On D6, the cell densities at the level of the treated batches are higher than that of the control batch. The "stimulating" effect is mainly manifested in the batch treated with 25 crg / ml: + 20% increase.

EXAMPLE 3 Biological Activity "Revenerating Dermal on Cultures of
fibroblasts
Fibroblast culture in a three-dimensional network of
collagen makes it possible to study the action of a pharmacological agent in a
physiological environment reproducing in vitro cell interactions
matrices existing in vivo. Within the collagen matrix, fibroblasts
find a differentiation close to that which they had in vivo.

The equivalent dermis is an important model for the biology of
skin and particularly for the pharmacology of wound healing because it is
a tissue that gradually reorganizes in which the fibroblasts
mature.

We compare the dynamic properties of cultured fibroblasts
in an equivalent dermis (collagen lattice) in the absence and in the presence of
different concentrations of the oligosaccharide of Example 1.

Concretely, assessing the behavior of fibroblasts
vis-à-vis the collagen matrix by evaluation of their contractile power
is performed according to the following test:
The fibroblast strain comes from explants of foreskin obtained
during surgeries in young children. They are
grown according to the routine techniques used in the laboratory in
Eagle's minimum essential medium (NIENI) supplemented with fetal calf serum
(SVF at 10% v / v).

To seed laths, human dermis fibroblasts
grown in monolayer are detached from the walls of the culture flasks
(NUNC) by trypsinization and centrifuged. Cells are put in cn
suspension in culture medium, so as to seed the laths
contained in Petri dishes 5 mm in diameter, with approximately 2 () () () () (> cells.

After counting at the Malassez cell, the cell suspension
is added in defined proportions to a mixture of culture medium and type I collagen, extracted with acetic acid from tendons of rat qucucs.

 The mixture is then poured into cold Petri dishes.

The oligosaccharides of Example 1 are introduced to differCnlcs
non-cytotoxic concentrations in the Lt culture medium mixture of collagen.

The equivalent dermes thus reconstituted (3 laths per batch) are
placed at 37 C. The fibroblasts which are distributed evenly in this
three-dimensional matrix attaches to the polymerized collagen network
and contract it. A gradual reduction in the diameter of the dermes
artificial is observed. The contractile power of fibroblasts is evaluated by
daily measurement of the area occupied by dermes using a
image analyzer (MICRONI).

The results indicated in the table below result from the
average of the results of three lattices, for a duration ranging from 1 to 4 days (D1 to
J4).

Two concentrations of products were tested. A control test
without addition of oligosaccharide is presented for comparison
Control Oligosaccharide Oligosaccharide
100 ssg / ml 50 crg / ml Jî 83 66% 80%
D2 65% 45% 48%
D3 54% 37% 48%
D4 42% 27% 33%
The addition of carrageenan oligosaccharides according to Example 1
stimulates the contractile power of fibroblasts.

EXAMPLE 4 Biological Activity "Regenerating Dermia" on Cultures of
fibroblasts whose contractile power is inhibited by hydrocortisone
The oligosaccharides are introduced into a culture of fibroblasts containing a quantity s

Control Witness treated Oligosaccharide Oligosaccharide
with at 200 pg / ml at 100 g / ml
hydrocortisone J1 68% 70% 57% 62%
D2 51% 68% 50% 56%
D3 37% 58% 45% 47%
D4 32% 62% 47% 50%
Hydrocortisone significantly slows dermal contraction
equivalents between OJ and J4. The addition of the different concentrations of
product removes the inhibition of the contraction of the laths generated by
hydrocortisone.

Claims (16)

 1) Sulfated galactan oligosaccharide, characterized in that it comprises from 2 to 20 saccharide units and has an average sulfation rate of at least 0.5 sulfate per saccharide unit.  2) sulfated galactan oligosaccharide according to claim 1, characterized in that it contains from 2 to 10 saccharide units.  3) sulfated galactan oligosaccharide according to one of claims 1 or 2, characterized in that the average sulfation rate is at least 0.7 sulfate per saccharide unit.  4) sulfated galactan oligosaccharide according to one of claims 1 to 3, characterized in that it can be obtained by depolymerization of carrageenan or agar.  5) sulfated galactan oligosaccharide according to claim A, characterized in that it can be obtained by depolymerization of iota carrageenan.  6) sulfated galactan oligosaccharide according to one of claims 1 to 5, characterized in that it is such that it causes an increase in the contractile power of fibroblasts of at least 10%, preferably at least 20% compared to the control which does not contain an oligosaccharide.  7) sulfated galactan oligosaccharide according to one of claims 1 to 5, characterized in that it is such that it partially lifts the inhibition of fibroblast contraction caused by the presence of hydrocortisone by at least 10% , preferably 20% compared to the control treated with hydrocortisone.  8) Mixture of sulfated galactan oligosaccharides, characterized in that it comprises at least 50% by weight of sulfated galactan oligosaccharide according to one of claims 1 to 7.  9) Mixture of sulfated galactan oligosaccharides according to claim 8, characterized in that it comprises at least 60% by weight of sulfated galactan oligosaccharide according to one of claims 1 to 7.  10) Composition intended for external topical application, characterized in that it comprises, as active principle, a galactan oligosaccharide or mixture of galactan oligosaccharides according to one of claims 1 to 9 and an appropriate support.  11) Cosmetic composition for external topical application, characterized in that it comprises, as active principle, a galactan oligosaccharide or mixture of galactan oligosaccharide according to one of claims 1 to 9 and an appropriate support.  12) Pharmaceutical composition for external topical application according to claim 11, characterized in that it comprises, as active principle, a galactan oligosaccharide or mixture of galactan oligosaccharide according to one of claims 1 to 7 and an appropriate support.  13) Use of galactan oligosaccharides or mixture of galactan oligosaccharides according to one of claims 1 to 9 as active ingredient for the preparation of compositions intended to promote the regeneration of the dermis.  14) Use according to claim 13 for the preparation of compositions intended to accelerate the healing process.  15) Use according to one of claims 13 or 14, characterized in that the compositions are compositions for external topical use.  16) Additive for cell culture consisting of sulfated galactan oligosaccharides according to one of claims 1 to 9.