The Italy-headquartered company previously launched the ingredient Zanthalene, an extract from the fruit husks of the Zanthoxylum bungeanum, or Szhechuan pepper, as an anti-itching ingredient.
However, due to its potential to inhibit synaptic transmission which can be felt in a tingling sensation on application, the company has investigated its potential for use as an anti-aging ingredient.
Short term effects, measured by a lifting effect, and longer term effects, measured by skin roughness parameters, were investigated in a double blind trial on the extract, the company explained in a recent article published in the International Journal of Cosmetic Science.
“The clinical trial in the latest publication has underlined it can provided a temporary (and fast) improvement of skin wrinkles, and this has been assessed in small, but double blind-controlled clinical trial,” Christian Artaria, marketing director at Indena, told CosmeticsDesign-Europe.com.
The company recruited 21 female volunteers for the study, aged between 35 and 65 who were divide into three study groups. Each study group applied two of three formulations, in a half face study, one containing no Zanthalene but a similar tingling ingredient, one containing Zanthalene at 2.0 percent and one with Zanthalene at 1.0 percent.
The use of an ingredient that had similar tingling sensations to the Zanthalene was an attempt to overcome the bias that the sensation could have on the study participants, who also performed self assessments, according to the company.
According to the study, the 1 percent formulation significantly improved skin roughness parameters and were judged as having a lifting effect by study participants, whereas for the 2 percent formulation, changes in skin roughness were not significant, and fewer study participants judged it as having a lifting effect.
In explaining this seemingly contradictory result, Artaria explained that efficacy and concentration are not necessarily proportional and can depend on other parameters such as the ability of the active to be ‘released’ on the skin.
“Also, the non linear dependence of the lifting activity on concentration might also reflect the activation of pathways with opposing effects, indicating that the overall profile is more favourable to relaxation at the lower concentration,” he added.
Muscle relaxing properties
Regarding the mechanism for the efficacy of the ingredient, Indena said further trials were underway to explore its muscle relaxing properties.
“The potential mechanism refers to the capability of alpha-hydroxy-sanshools to relax subcutaneous muscles with a mainly ionotropic mechanism involving sodium channels, GABA-A receptors or two pore K channels. Additional investigations are currently being carried out on GABA receptors,” he said.
Source: International Journal of Cosmetic Science
Lifting properties of the alkamide fraction from the fruit husks of the Zanthoxylum bungeanum
C. Artaria, G. Maramaldi, A, Bonfigli, L. Rigano and G. Appendino