Arabinose Formulations and Uses

Abstract

The present disclosure provides methods for treating or preventing inflammatory skin conditions and methods for regulating and maintaining homeostasis of the skin microbiota, comprising administering a topical formulation comprising arabinose, particularly L-arabinose, wherein the concentration of arabinose in the topical formulation is effective to promote or maintain one or more species of skin bacteria that convey a beneficial effect and / or inhibit or maintain one or more species of skin bacteria that convey a harmful effect, and topical compositions of arabinose, particularly L-arabinose, useful in such methods.

Description

[Technical Field]

[0001] The present disclosure relates to arabinose formulations and the use of arabinose, particularly L-arabinose, to promote a healthy skin microbiome and treat inflammatory skin conditions. [Background technology]

[0002] Arabinose (C5H 10 Arabinose (O5) is an aldopentose, i.e., a monosaccharide containing five carbon atoms, which in its linear form contains an aldehyde (CHO) functional group. Arabinose exists in the "D" or "L" form, i.e., as D-arabinose or L-arabinose, respectively. L-arabinose is more common in nature than D-arabinose and is the preferred form according to the present invention. L-arabinose, in its linear aldehyde form,

[0003] [ka] or in the form of a five-membered ring (L-arabinofuranose),

[0004] [ka] Or it can exist in the form of a six-membered ring (L-arabinopyranose).

[0005] [ka]

[0006] L-arabinose occurs naturally in most plants. It has found utility as a "sugar blocker" in dietary supplements due to its ability to block sucrose absorption by inhibiting intestinal sucrase, the enzyme that breaks down sucrose into glucose and fructose.

[0007] Arabinose (such as L-arabinose, D-arabinose, or a mixture thereof) is commercially available or can be prepared as described in the literature. For example, L-arabinose can be prepared as described in WO2021 / 123004A1. Furthermore, methods for preparing the arabinose-containing formulations / compositions disclosed herein are well known to those skilled in the art.

[0008] Human skin is densely colonized by a diverse and active population of microorganisms—bacteria, fungi, viruses, and mites—that collectively form the skin microbiome. While many skin care products are advertised as having "antibacterial" properties, highlighting the potential for microorganisms on the skin to cause disease and contamination, the skin microbiome also contributes to the protective function of human skin in many ways. Extensive communication and complex interactions exist between bacteria, skin cells, and immune cells. These interactions, in some cases, help strengthen and repair the skin barrier, enhance the body's defenses against infection, and reduce excessive inflammation. Disruptions in this ecosystem can leave the skin susceptible to immune hypersensitivity disorders such as atopic dermatitis and skin allergies, or impede healing in people with chronic wounds. Furthermore, an imbalance in the skin microbiome can lead to severe skin lesions. Because the skin microbiome is so important for skin health, better ways to control it to promote beneficial microorganisms while suppressing harmful microorganisms are needed. Summary of the Invention

[0009] It has been discovered that L-arabinose has important beneficial effects on the skin microbiome, providing important and unexpected benefits in addressing a variety of conditions.

[0010] Using metagenomic sequencing, we determined the effects of various concentrations of L-arabinose on skin microbiota homeostasis. We found that a 0.5% concentration of L-arabinose promoted Acinetobacter baumannii, a key finding suggesting that Acinetobacter species protect against allergic sensitization and inflammation through the activation of interleukin-10 (IL-10). IL-10 is a cytokine with potent anti-inflammatory properties and plays an essential role in limiting the host immune response to pathogens. At the same time, these concentrations of L-arabinose inhibited Micrococcus luteus. Micrococcus luteus appears to have a dual role: it prevents skin membrane infection and aids in DNA repair from UV damage, while simultaneously favoring early infection from pathogenic bacteria such as Staphylococcus aureus. Limiting skin inflammation may reduce chronic inflammation associated with aging and therefore reduce the effects of aging. Therefore, preventing a cross-contributing factor in the aging process, immune dysfunction in inflammatory pathways, may be essential to halt the propagation of aging-related tissue deterioration. Thus, the effect of L-arabinose on the skin microbiota at a concentration of 0.5% may protect against inflammation and prevent or reduce sensitive skin (and thus prevent skin aging also associated with chronic inflammation).

[0011] At higher concentrations (3.5% and 5%), L-arabinose promotes Streptococcus mitis, a bacterium known to limit the virulence of Staphylococcus aureus, which is involved in atopic dermatitis and cellulitis. Furthermore, at concentrations of 1% and 2% (especially 1%), L-arabinose has the effect of maintaining the homeostasis of the skin microbiota.

[0012] Accordingly, the present disclosure provides methods for promoting a healthy skin microbiota, e.g., methods for protecting against or reducing skin inflammation (including allergic sensitization, chronic inflammation associated with aging, atopic dermatitis, and cellulitis), and methods for controlling and maintaining skin microbiota homeostasis by promoting skin bacteria that have beneficial effects and / or inhibiting bacteria that have harmful effects, e.g., bacteria including the infectious pathogen Staphylococcus aureus, comprising topically administering an effective amount of arabinose, particularly L-arabinose, to the skin of a subject, such as a mammalian subject, particularly a human subject, in need thereof.

[0013] The present disclosure also provides arabinose, particularly L-arabinose, and topical compositions comprising arabinose, particularly L-arabinose, for use in the described methods. [Brief explanation of the drawings]

[0014] [Figure 1] The relative abundance of bacteria in non-treated and non-stressed (NT-NS) control conditions after sequencing is shown. [Figure 2] The relative abundance of Acinetobacter baumannii at different concentrations of L-arabinose is shown. [Figure 3] The relative abundance of Micrococcus luteus at different concentrations of L-arabinose is shown. [Figure 4] 1 shows the relative abundance of Staphylococcus epidermidis at different concentrations of L-arabinose. [Figure 5] The relative abundance of Streptococcus mitis at different concentrations of L-arabinose is shown. [Figure 6] Figure 1 shows the relative abundance of bacteria in the skin microbiota mixture at different concentrations of L-arabinose. DETAILED DESCRIPTION OF THE INVENTION

[0015] In a first embodiment, the present disclosure provides a method (Method 1) for treating or preventing an inflammatory skin condition in a subject, such as a mammalian subject, particularly a human subject, in need thereof, comprising administering to the skin of the subject a topical formulation comprising arabinose, particularly L-arabinose, wherein the concentration of arabinose in the topical formulation is effective to promote or maintain one or more species of skin bacteria (particularly one) that provide a beneficial effect and / or inhibit or maintain one or more species of skin bacteria (particularly one or two) that provide a harmful effect. For example, Method 1 includes the following methods: 1.1 Method 1, wherein the topical formulation is effective to promote one or more (especially one) species of skin bacteria that have a beneficial effect and / or inhibit one or more (especially one or two) species of skin bacteria that have a harmful effect.

[0016] 1.2 Any of the foregoing methods, wherein the topical formulation is effective in maintaining one or more species of skin bacteria that provide a beneficial effect and / or in maintaining one or more species of skin bacteria that provide a harmful effect.

[0017] 1.3 Any of the preceding methods, wherein the concentration of arabinose in the topical formulation is between 0.1% and 10%.

[0018] 1.4 Any of the preceding methods, wherein the concentration of arabinose in the topical formulation is 0.1% to 5%, 0.5% to 5%, 0.5% to 3%, 0.1% to 1%, 0.5% to 1%, 1% to 2%, 2.5% to 5%, 3% to 5%, or 3.5% to 5%.

[0019] 1.5 Any of the preceding methods, wherein the concentration of arabinose in the topical formulation is about 0.5%, about 1%, about 2%, about 2.5%, about 3%, about 3.5%, about 4%, or about 5%.

[0020] 1.6 Any of the aforementioned methods for preventing allergic sensitization.

[0021] 1.7 Any of the foregoing methods for treating chronic inflammation of the skin associated with aging.

[0022] 1.8 Any of the foregoing methods for treating atopic dermatitis.

[0023] 1.9 Any of the foregoing methods for treating cellulitis.

[0024] 1.10 Any of the preceding methods wherein the condition being treated or prevented is characterized by increased levels of IL-10.

[0025] 1.11 Any of the foregoing methods wherein the bacteria providing the beneficial effect comprises an Acinetobacter species, in particular Acinetobacter baumannii.

[0026] 1.12 Any of the preceding methods, wherein the subject exhibits increased levels of Acinetobacter species, particularly Acinetobacter baumannii, on the skin after administration of the topical formulation.

[0027] 1.13 Any of the foregoing methods wherein the bacteria producing the beneficial effect comprises Streptococcus mitis.

[0028] 1.14 Any of the preceding methods, wherein the subject exhibits increased levels of Streptococcus mitis on the skin after administration of the topical formulation.

[0029] 1.15 Any of the preceding methods wherein the bacteria causing the harmful effect comprises Staphylococcus aureus.

[0030] 1.16 Any of the preceding methods, wherein the subject exhibits a decrease in the level of Staphylococcus aureus on the skin after administration of the topical formulation.

[0031] 1.17 Any of the foregoing methods wherein the harmful bacteria comprises Micrococcus luteus.

[0032] 1.18 Any of the preceding methods, wherein the subject exhibits reduced levels of Micrococcus luteus on the skin following administration of the topical formulation.

[0033] 1.19 Any of the aforementioned methods for treating chronic skin inflammation associated with aging, wherein the concentration of arabinose in the topical formulation is 0.1% to 1%, particularly about 0.5%.

[0034] 1.20 Any of the preceding methods for treating atopic dermatitis, wherein the concentration of arabinose in the topical formulation is 3% to 5%, particularly 3.5% to 5%.

[0035] 1.21 Any of the preceding methods, wherein the topical formulation is applied to the skin once or twice daily.

[0036] 1.22 Any of the preceding methods, wherein the administration period is at least one week, e.g., at least one month.

[0037] 1.23 Any of the preceding methods wherein the formulation contains no sugars other than arabinose.

[0038] 1.24 Any of the preceding methods, wherein the arabinose is L-arabinose.

[0039] 1.25 Any of the preceding methods, wherein the topical formulation is in the form of a cream, lotion, spray, ointment, serum, lip balm, makeup, soap, shower gel, shampoo, hair conditioner, or hair mask.

[0040] The present disclosure further provides arabinose, particularly L-arabinose, for use in treating or preventing an inflammatory skin condition in a subject, such as a mammalian subject, particularly a human subject, in need thereof, by administering a topical formulation comprising arabinose, particularly L-arabinose, to the skin of the subject, wherein the concentration of arabinose in the topical formulation is effective to promote or maintain one or more (particularly one) species of skin bacteria that provide a beneficial effect and inhibit or maintain one or more (particularly one or two) species of skin bacteria that provide a harmful effect, for example for use in a method according to any one of methods 1.1 to 1.25 above.

[0041] When it is said herein that a species of skin bacteria is promoted, it means that the relative amount of that species of bacteria is increased compared to the total amount of skin bacteria, whereas when it is said that a certain type of skin bacteria is inhibited, it means that the relative amount of that species of bacteria is decreased compared to the total amount of skin bacteria.

[0042] When it is said herein that a species of skin bacteria is maintained, it means that the relative amount of that species of bacteria is maintained compared to the total amount of skin bacteria.

[0043] Unless otherwise stated, percentages refer to weight percentages (wt%).

[0044] The term "about" placed before a numerical value "X" refers in this application to an interval ranging from 30% of X minus X to 30% of X plus X, preferably an interval ranging from 10% of X minus X to 10% of X plus X.

[0045] The present disclosure also provides a method (Method 2) for regulating and maintaining skin microbiota homeostasis, comprising administering to the skin of a subject, such as a mammalian subject, particularly a human subject, a topical formulation comprising arabinose, particularly L-arabinose, wherein the concentration of arabinose in the topical formulation is effective to promote or maintain one or more species of skin bacteria (particularly one) that provide a beneficial effect and / or inhibit or maintain one or more species of skin bacteria (particularly one or two) that provide a harmful effect. For example, Method 2 includes the following methods. 2.1 Method 2, wherein the topical formulation is effective to promote one or more (especially one) species of skin bacteria that have a beneficial effect and / or inhibit one or more (especially one or two) species of skin bacteria that have a harmful effect.

[0046] 2.2 Any of the foregoing methods wherein the topical formulation is effective in maintaining one or more species of skin bacteria that provide a beneficial effect and / or maintaining one or more species of skin bacteria that provide a harmful effect.

[0047] 2.3 Any of the preceding methods, wherein the concentration of arabinose in the topical formulation is between 0.1% and 10%.

[0048] 2.4 Any of the preceding methods, wherein the concentration of arabinose in the topical formulation is 0.1% to 5%, 0.5% to 5%, 0.5% to 3%, 0.1% to 1%, 0.5% to 1%, 1% to 2%, 2.5% to 5%, 3% to 5%, or 3.5% to 5%.

[0049] 2.5 Any of the preceding methods, wherein the concentration of arabinose in the topical formulation is about 0.5%, about 1%, about 2%, about 2.5%, about 3%, about 3.5%, about 4%, or about 5%.

[0050] 2.6 Any of the foregoing methods wherein the bacteria providing the beneficial effect comprises an Acinetobacter species, in particular Acinetobacter baumannii.

[0051] 2.7 Any of the preceding methods, wherein the subject exhibits increased levels of Acinetobacter species, particularly Acinetobacter baumannii, on the skin following administration of the topical formulation.

[0052] 2.8 Any of the foregoing methods wherein the bacteria producing the beneficial effect comprises Streptococcus mitis.

[0053] 2.9 Any of the foregoing methods, wherein the subject exhibits increased levels of Streptococcus mitis on the skin following administration of the topical formulation.

[0054] 2.10 Any of the foregoing methods wherein the bacteria causing the harmful effect comprises Staphylococcus aureus.

[0055] 2.11 Any of the preceding methods, wherein the subject exhibits a decrease in the level of Staphylococcus aureus on the skin after administration of the topical formulation.

[0056] 2.12 Any of the foregoing methods wherein the harmful bacteria comprises Micrococcus luteus.

[0057] 2.13 Any of the preceding methods, wherein the subject exhibits a decrease in the level of Micrococcus luteus on the skin after administration of the topical formulation.

[0058] 2.14 Method 2 for maintaining skin microbiota homeostasis, wherein the concentration of arabinose in the topical formulation is 1% to 2%, for example about 1% or about 2%, in particular about 1%.

[0059] 2.15 Any of the preceding methods, wherein the topical formulation is applied to the skin once or twice daily.

[0060] 2.16 Any of the preceding methods, wherein the administration period is at least one week, e.g., at least one month.

[0061] 2.17 Any of the preceding methods, wherein the formulation contains no sugars other than arabinose.

[0062] 2.18 Any of the preceding methods, wherein the arabinose is L-arabinose.

[0063] 2.19 Any of the preceding methods, wherein the topical formulation is in the form of a cream, lotion, spray, ointment, serum, lip balm, makeup, soap, shower gel, shampoo, hair conditioner, or hair mask.

[0064] The present disclosure further provides a topical pharmaceutical or cosmetic composition (Composition 1) comprising arabinose, particularly L-arabinose, wherein the concentration of arabinose in the topical composition is 0.1% to 10%. For example, Composition 1 comprises the following components: 3.1 Composition 1, wherein the concentration of arabinose is 0.1% to 5%, 0.5% to 5%, 0.5% to 3%, 0.1% to 1%, 0.5% to 1%, 1% to 2%, 2.5% to 5%, 3% to 5%, or 3.5% to 5%.

[0065] 3.2 Any of the preceding compositions, wherein the concentration of arabinose is about 0.5%, about 1%, about 2%, about 2.5%, about 3%, about 3.5%, about 4%, or about 5%.

[0066] 3.3 Any of the foregoing compositions that are effective in promoting Acinetobacter species, particularly Acinetobacter baumannii, on human skin.

[0067] 3.4 Any of the foregoing compositions that are effective in promoting Streptococcus mitis on human skin.

[0068] 3.5 Any of the foregoing compositions that are effective in inhibiting Staphylococcus aureus on human skin.

[0069] 3.6 Any of the foregoing compositions that are effective in inhibiting Micrococcus luteus on human skin.

[0070] 3.7 Any of the foregoing compositions in the form of a cream, lotion, spray, ointment, serum, lip balm, makeup, soap, shower gel, shampoo, hair conditioner, or hair mask.

[0071] 3.8 Any of the preceding compositions further comprising a fragrance.

[0072] 3.9 Any of the preceding compositions that does not contain sugars other than arabinose.

[0073] 3.10 Any of the preceding compositions wherein the arabinose is L-arabinose.

[0074] 3.11 Any of the preceding compositions for use in any one of Methods 1-1.25 or Methods 2-2.19 above.

[0075] Example: Evaluating the effect of L-arabinose on the growth of common skin bacteria The purpose of this experiment was to evaluate the effect of different concentrations of L-arabinose on a bacterial pool mimicking the skin microbiome by quantifying the bacterial mixture using metagenomic sequencing. Five different types of bacteria were obtained from ATCC®: Micrococcus luteus (catalog no. 4698), Corynebacterium striatum (catalog no. BAA-1293), Staphylococcus epidermidis (catalog no. 12228), Acinetobacter baumannii (catalog no. 19606), and Streptococcus mitis (catalog no. NCIMB-13770). The bacteria were common skin bacteria selected to roughly mimic the skin microbiome. Bacteria are grown on specific media, either solid (Brain Heart Infusion (BHI) Agar from Condalab (Cat. No. 1048.00) or Trypticase Soy (TS) Agar from Condalab (Cat. No. 1068.00)) or liquid (Brain Heart Infusion Broth from Condalab (Cat. No. 1400.00) or Trypticase Soy Broth from Condalab (Cat. No. 1224.00)). Bacterial cultures are performed according to ATCC instructions and adapted to the specific conditions of each bacterium: all bacteria are grown in BHI medium at 37 °C in an aerobic environment with shaking at 120 rpm, except for Streptococcus mitis, which requires an anaerobic environment and is therefore grown without shaking and with paraffin oil from Sigma-Aldrich (Cat. No. 185812) on the medium to block contact with air.

[0076] Growth kinetics was performed for each bacterium to determine its different growth phases, particularly the time required to reach the exponential growth phase. Aerobically growing bacteria were plated on solid medium, and then colonies were inoculated into 10 mL of liquid medium. The OD at 600 nm was then measured at regular time intervals from TO (time of inoculation) to obtain a growth curve until the stationary phase was reached. Anaerobically growing bacteria were directly inoculated into 9.5 mL of medium at 500 μL.

[0077] The bacteria are treated with L-arabinose diluted in culture medium for 6 hours. L-arabinose is initially resuspended in culture medium at a concentration of 5%. The following dilutions are made directly in the culture medium at the following concentrations: 3.5%, 2%, 1% and 0.5%.

[0078] Each bacterium from the mixture is first grown independently. Once the exponential growth phase begins, Corynebacterium striatum, Micrococcus luteus, and Staphylococcus epidermidis are mixed and grown for 6 hours in the presence or absence of different concentrations of L-arabinose before reaching stationary phase. Acinetobacter baumannii and Streptococcus mitis are grown independently with L-arabinose and drawn into the final mixture due to their specific properties (Biosafety Level 2 (BSL-2) bacteria and anaerobic growth for Streptococcus mitis). The mixture is then centrifuged and sent for sequencing. Bacterial DNA is isolated and sequenced, and the 16S rRNA sequences are matched to taxonomic databases.

[0079] As shown in Figure 1, all bacteria except Corynebacterium striatum can grow in the mixture. Figure 1 shows the relative abundance of bacteria in the non-treated and non-stressed (NT-NS) control condition after sequencing. The relative bacterial abundance is detected in the NT-NS control sample after metagenomic sequencing. The bacteria seeded in the mixture are Micrococcus luteus, Corynebacterium striatum, Staphylococcus epidermidis, Acinetobacter baumannii, and Streptococcus mitis. All detected operational taxonomic units (OTUs) are classified by genus to allow differentiation of all bacteria present.

[0080] Figure 2 shows the relative abundance of Acinetobacter baumannii at different concentrations of L-arabinose. Relative Acinetobacter baumannii abundance is compared in all samples after metagenomic sequencing. Bacteria are treated with five concentrations of L-arabinose: 0.5%, 1%, 2%, 3.5%, and 5%. Only OTUs identifying the genus Acinetobacter baumannii are shown.

[0081] Statistical analysis for Figures 2–5 is performed using unpaired two-tailed t-tests for NT-NS ( * p-value < 0.05, ** p-value < 0.01, *** p-value<0.001).

[0082] Figure 2 shows that L-arabinose has a dose-dependent effect on Acinetobacter baumannii. It increases by 7% when 0.5% L-arabinose is used compared to the NT-NS control, and statistically decreases by 7% at 5% L-arabinose. The relative abundance of Acinetobacter baumannii is the same as the control when 1% or 2% L-arabinose is used.

[0083] Figure 3 shows the relative abundance of Micrococcus luteus at different concentrations of L-arabinose. The relative abundance of Micrococcus luteus is compared in all samples after metagenomic sequencing. Bacteria are treated with five concentrations of L-arabinose: 0.5%, 1%, 2%, 3.5%, and 5%. Only OTUs identifying the genus Micrococcus luteus are shown.

[0084] As shown in Figure 3, 0.5% L-arabinose in the mixture statistically decreases the relative abundance of Micrococcus luteus compared to the control condition. At 2% L-arabinose, there is a statistically significant increase in Micrococcus luteus. At 1%, 3.5%, or 5% L-arabinose, there is no statistically significant change in the relative abundance of Micrococcus luteus.

[0085] Figure 4 shows the relative abundance of Staphylococcus epidermidis at different concentrations of L-arabinose. The relative abundance of Staphylococcus epidermidis is compared in all samples after metagenomic sequencing. Bacteria are treated with five concentrations of L-arabinose: 0.5%, 1%, 2%, 3.5%, and 5%. Only OTUs identifying the genus Staphylococcus epidermidis are shown.

[0086] Figure 4 shows a trend toward a decrease in the relative abundance of S. epidermidis after treatment with 0.5% L-arabinose compared to the control condition. There is no statistical difference in the relative abundance of S. epidermidis at other concentrations.

[0087] Figure 5 shows the relative abundance of Streptococcus mitis at different concentrations of L-arabinose. Relative Streptococcus mitis abundance is compared in all samples after metagenomic sequencing. Bacteria are treated with five concentrations of L-arabinose: 0.5%, 1%, 2%, 3.5%, and 5%. Only OTUs identifying the genus Streptococcus mitis are shown.

[0088] As shown in Figure 5, L-arabinose has a dose-dependent effect on Streptococcus mitis. At 0.5% and 1%, L-arabinose tends to decrease the relative abundance of Streptococcus mitis, but at 3.5% and 5%, it statistically increases the relative abundance of Streptococcus mitis by more than two-fold. The relative abundance of Streptococcus mitis is the same as the control with 2% L-arabinose.

[0089] Figure 6 shows the relative abundance of bacteria in the skin microbiota mixture at different concentrations of L-arabinose. Relative bacterial abundance was detected in all samples after metagenomic sequencing. The bacteria inoculated into the mixture were Micrococcus luteus, Corynebacterium striatum, Staphylococcus epidermidis, Acinetobacter baumannii, and Streptococcus mitis. The bacteria were treated with five concentrations of L-arabinose: 0.5%, 1%, 2%, 3.5%, and 5%. All detected OTUs were classified by genus, allowing differentiation of all bacteria present in all samples.

[0090] Looking at the total extract, Figure 6 shows that Acinetobacter baumannii outgrows other bacteria in mixtures containing 0.5% L-arabinose. At 3.5% and 5% L-arabinose, Streptococcus mitis grows rapidly at the expense of Acinetobacter baumannii. Finally, bacterial mixtures containing 1% or 2% L-arabinose maintain the homeostasis of the skin microbiota. There are no significant differences compared to the NT-NS control.

Claims

1. 1. A method for treating or preventing an inflammatory skin condition in a subject in need thereof, comprising administering to the skin of the subject a topical formulation comprising arabinose, wherein the concentration of arabinose in the topical formulation is effective to promote or maintain one or more species of skin bacteria that have a beneficial effect and / or inhibit or maintain one or more species of skin bacteria that have a harmful effect.

2. 10. The method of claim 1, wherein the condition to be prevented or treated is allergic sensitization, chronic inflammation of the skin associated with aging, atopic dermatitis, or cellulitis.

3. 1. A method for controlling and maintaining skin microbiota homeostasis, comprising administering to the skin of a subject a topical formulation comprising arabinose, wherein the concentration of arabinose in the topical formulation is effective to promote or maintain one or more species of skin bacteria that have beneficial effects and / or inhibit or maintain one or more species of skin bacteria that have harmful effects.

4. 4. The method of any one of claims 1 to 3, wherein the bacteria that provide a beneficial effect include Acinetobacter species or Streptococcus mitis.

5. 5. The method of any one of claims 1 to 4, wherein the bacteria causing harmful effects include Staphylococcus aureus or Micrococcus luteus.

6. 6. The method of any one of claims 1 to 5, wherein the concentration of arabinose in the topical formulation is from 0.1% to 10%.

7. 7. The method of any one of claims 1 to 6, wherein the concentration of arabinose in the topical formulation is 0.1% to 5%, 0.5% to 5%, 0.5% to 3%, 0.1% to 1%, 0.5% to 1%, 1% to 2%, 2.5% to 5%, 3% to 5%, or 3.5% to 5%.

8. 3. The method of claim 1 or 2 for treating chronic skin inflammation associated with aging, wherein the concentration of arabinose in the topical formulation is 0.1% to 1%.

9. 3. The method of claim 1 or 2 for treating atopic dermatitis, wherein the concentration of arabinose in the topical formulation is 3% to 5%.

10. The method of any one of claims 1 to 9, wherein the formulation contains no sugars other than arabinose.

11. The method according to any one of claims 1 to 10, wherein the arabinose is L-arabinose.

12. A topical pharmaceutical or cosmetic composition comprising arabinose, wherein the concentration of arabinose in the topical composition is from 0.1% to 10%.

13. 13. The topical composition of claim 12, wherein the concentration of arabinose is 0.1% to 5%, 0.5% to 5%, 0.5% to 3%, 0.1% to 1%, 0.5% to 1%, 1% to 2%, 2.5% to 5%, 3% to 5%, or 3.5% to 5%.

14. 14. The topical composition of claim 12 or 13, which is free of sugars other than arabinose.

15. The topical composition of any one of claims 12 to 13, wherein the arabinose is L-arabinose.

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