title: Employing photoacoustic spectroscopy in the evaluation of the skin permeation profile of emulsion containing antioxidant phenolic-rich extract of Melochia arenosa.
abstract: BACKGROUND
  Oxidative stress is an important factor modulating skin alterations. Melochia arenosa Benth. (Malvaceae) is a Brazilian plant with antimicrobial activity and antioxidant potential.
  
  
  OBJECTIVE
  The objective of this study is to develop a topical formulation containing antioxidant phenolic-rich extract of M. arenosa and to evaluate its skin permeation profile.
  
  
  METHODS
  Response surface methodology was used to maximize the total phenolic (TP) content of the extract and its antioxidant activity was evaluated by 2,2-diphenyl-1-picryl-hydrazyl (DPPH), 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and respiratory burst methods. An emulsion containing 1% optimized extract (OE) was developed and employed photoacoustic spectroscopy (PAS) for the determination of its skin permeation profile. The morphology of the skin was studied in histological sections stained with hematoxylin-eosin.
  
  
  CONCLUSIONS
  The optimum conditions predicted for the major extractive efficiency of the phenolics with 100% ethanol led extraction time 101 h and plant:solvent proportion 1:13.5 (w/v). OE presented TP = 724.6 ± 8.2 mg GAE/g extract and scavenging capacity of DPPH (IC50 value = 11.43 ± 0.14 µg/mL) and ABTS radicals (IC50 value = 35.42 ± 0.48 µg/mL). The production of ROS by neutrophils after stimulation with phorbol miristate acetate was lower when the OE was present in the reaction medium, endorsing its high antioxidant capacity. The data obtained by PAS indicated that the OE present in the emulsion has permeated and was distributed in the whole skin. No histopathological alterations were observed in the histological analysis.
  
  
  CONCLUSIONS
  The formulation developed is a promising tool for skin care and could prevent the damage caused by oxidative stress.
authors: a Departamento de Farmácia and.
authors: Luana Magri
authors: LM
authors: Tunin
authors: a Departamento de Farmácia and.
authors: Fernanda Belincanta
authors: FB
authors: Borghi
authors: b Departamento de Física , Universidade Estadual de Maringá , Maringá PR , Brazil .
authors: Ana Claudia
authors: AC
authors: Nogueira
authors: c Departamento de Patologia, Análises Clínicas e Toxicológicas , Universidade Estadual de Londrina , Londrina PR , Brazil , and.
authors: Luciana
authors: L
authors: Higachi
authors: c Departamento de Patologia, Análises Clínicas e Toxicológicas , Universidade Estadual de Londrina , Londrina PR , Brazil , and.
authors: Décio Sabbatini
authors: DS
authors: Barbosa
authors: b Departamento de Física , Universidade Estadual de Maringá , Maringá PR , Brazil .
authors: Mauro Luciano
authors: ML
authors: Baesso
authors: d Departamento de Ciências Morfológicas , Universidade Estadual de Maringá , Maringá PR , Brazil.
authors: Luzmarina
authors: L
authors: Hernandes
authors: a Departamento de Farmácia and.
authors: Andréa
authors: A
authors: Diniz
authors: a Departamento de Farmácia and.
authors: Maria da Conceição Torrado
authors: Mda C
authors: Truiti
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D004655:Emulsions; D006801:Humans; D008297:Male; D019660:Malvaceae / Q000737:chemistry*; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism; D010539:Permeability; D010636:Phenols / Q000008:administration & dosage / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D061088:Photoacoustic Techniques; D008517:Phytotherapy; D035261:Plant Components, Aerial; D010936:Plant Extracts / Q000008:administration & dosage / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D010946:Plants, Medicinal; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D016897:Respiratory Burst / Q000187:drug effects; D012867:Skin / Q000378:metabolism*; D012869:Skin Absorption; D013057:Spectrum Analysis; D013997:Time Factors
chemical_list: D000975:Antioxidants; D004655:Emulsions; D010636:Phenols; D010936:Plant Extracts; D017382:Reactive Oxygen Species
keywords: Central composite design; oxidative stress; skin care; skin penetration