Amelioration of imiquimod-induced psoriasis-like dermatitis in mice by DSW therapy inspired hydrogel

Psoriasis is a long-lasting and recurrent autoimmune disease which is incurable so far.Dead Sea water(DSW)therapy is an effective approach to help control the symptoms of psoriasis due to the abundant mineral ions in DSW,which inspired the material formulation in this study.Rubidium–Sodium alginate/Polyacrylamide hydrogels(Rb-SA/PAAm gels)composed of sodium alginate and polyacrylamide interpenetrating network structure with different concentrations of rubidium and certain magnesium and zinc content were prepared for the treatment of psoriasis.The obtained results suggest the good mechanical properties of the Rb-SA/PAAm gels including toughness and swelling performance.In terms of in vitro tests,the Rb-SA/PAAm gels not only show nontoxicity to human keratinocyte cell line(Hacats)but also inhibits the activity against inflammatory NF-κβ signaling pathway.Meanwhile,they can release Rb+which enable the Rb-SA/PAAm gels have better antibacterial ability to Streptococcus and Escherichia coli.The results obtained from in vivo tests indicate that these hydrogels could alleviate the symptoms of psoriasis caused by Imiquimod(IMQ)in mice by reducing the inflammatory factor in STAT3 pathway and therefore reduce the immune stimulation of the spleen.In conclusion,the 100Rb-SA/PAAm gel has demonstrated great potential to be a topical wettable dressing for psoriasis treatment.

Retraction notice to“Amelioration of imiquimod-induced psoriasis-like dermatitis in mice by DSW therapy inspired hydrogel”[BIOMAT 6(2021)299-311]

This article has been retracted:please see Elsevier Policy on Article Withdrawal(https://www.elsevier.com/about/our-business/policies/article-withdrawal).This article has been retracted at the request of all the Authors,the Editor-in-Chief and the owner of the journal.The article has been retracted because of the authors recently re-conducted partly the experiments and found that the anti-bacteria behavior of Rb+was not reproducible.As shown in Fig.1(see enclosed file),at a centration as high as 200 mM,the addition of single Rb+does not show anti-bacteria effect.In Fig.2(see enclosed file),the authors prepared a mixed solution containing Rb+,Mg2+and Zn2+with concentrations close to those(12 h)in the article,and found that the mixed solution does not show anti-bacterial effect either.The two figures indicate that the anti-bacteria effect of Rb+is not conclusive,which seriously impairs the rigidity of the paper.Considering complex factors influencing the experiments with hydrogels,there might be other effects on the anti-bacteria behavior.However,since the anti-bacteria effect of Rb+is incorrect,the authors would like to retract the published article.