Oral submucous fibrosis(OSF)is a chronic and inflammatory mucosal disease caused by betel quid chewing,which belongs to oral potentially malignant disorders.Abnormal fibroblast differentiation leading to disordered collagen metabolism is the core process underlying OSF development.The epithelium,which is the first line of defense against the external environment,can convert external signals into pathological signals and participate in the remodeling of the fibrotic microenvironment.However,the specific mechanisms by which the epithelium drives fibroblast differentiation remain unclear.In this study,we found that Arecoline-exposed epithelium communicated with the fibrotic microenvironment by secreting exosomes.MiR-17-5p was encapsulated in epithelial cell-derived exosomes and absorbed by fibroblasts,where it promoted cell secretion,contraction,migration and fibrogenic marker(α-SMA and collagen type I)expression.The underlying molecular mechanism involved miR-17-5p targeting Smad7 and suppressing the degradation of TGF-β receptor 1(TGFBR1)through the E3 ubiquitination ligase WWP1,thus facilitating downstream TGF-β pathway signaling.Treatment of fibroblasts with an inhibitor of miR-17-5p reversed the contraction and migration phenotypes induced by epithelial-derived exosomes.Exosomal miR-17-5p was confirmed to function as a key regulator of the phenotypic transformation of fibroblasts.In conclusion,we demonstrated that Arecoline triggers aberrant epithelium-fibroblast crosstalk and identified that epithelial cell-derived miR-17-5p mediates fibroblast differentiation through the classical TGF-β fibrotic pathway,which provided a new perspective and strategy for the diagnosis and treatment of OSF.

Oral submucous fibrosis(OSF)is a chronic and inflammatory mucosal disease caused by betel quid chewing,which belongs to oral potentially malignant disorders.Abnormal fibroblast differentiation leading to disordered collagen metabolism is the core process underlying OSF development.The epithelium,which is the first line of defense against the external environment,can convert external signals into pathological signals and participate in the remodeling of the fibrotic microenvironment.However,the specific mechanisms by which the epithelium drives fibroblast differentiation remain unclear.In this study,we found that Arecoline-exposed epithelium communicated with the fibrotic microenvironment by secreting exosomes.MiR-17-5p was encapsulated in epithelial cell-derived exosomes and absorbed by fibroblasts,where it promoted cell secretion,contraction,migration and fibrogenic marker(α-SMA and collagen type I)expression.The underlying molecular mechanism involved miR-17-5p targeting Smad7 and suppressing the degradation of TGF-β receptor 1(TGFBR1)through the E3 ubiquitination ligase WWP1,thus facilitating downstream TGF-β pathway signaling.Treatment of fibroblasts with an inhibitor of miR-17-5p reversed the contraction and migration phenotypes induced by epithelial-derived exosomes.Exosomal miR-17-5p was confirmed to function as a key regulator of the phenotypic transformation of fibroblasts.In conclusion,we demonstrated that Arecoline triggers aberrant epithelium-fibroblast crosstalk and identified that epithelial cell-derived miR-17-5p mediates fibroblast differentiation through the classical TGF-β fibrotic pathway,which provided a new perspective and strategy for the diagnosis and treatment of OSF.

OBJECTIVETo optimize the the ultrasound-assisted subcritical water extraction (USWE) parameters of proanthocyanidins from defatted grape seed, study antioxidant activity of proanthocyanidins and compare the effects of USWE and other extraction techniques.

METHODThe 2 L equipment of USWE was designed and used to extract the proanthocyanidins. The factors including extraction temperature, extraction time and extraction pressure were studied. The best extraction condition was found through the response surface design. Antioxidant activity of proanthocyanidins was studied by its DPPH free radical and NaNO2 scavenging action.

RESULTThe USWE parameters were extraction temperature 145 degrees C, extraction time 18 min, extraction pressure 14 MPa and the extraction yield (EY) was 4.05% under this extraction condition. The proanthocyanidins extracted under this optimized extraction condition had better scavenging action on DPPH free radical and NaNO2. As compared with the conventional soxhlet's extraction and heat reflux extraction, the USWE cost less extraction time, and possessed high efficiency and so on.

CONCLUSIONThe extraction technology of USWE is highly feasible to extract proanthocyanidins from defatted grape seed.

Analysis of Variance ; Chemical Fractionation ; methods ; Free Radical Scavengers ; isolation & purification ; pharmacology ; Pressure ; Proanthocyanidins ; isolation & purification ; pharmacology ; Seeds ; chemistry ; Temperature ; Time Factors ; Ultrasonics ; Vitis ; chemistry ; Water ; chemistry