In vitro and in vivo effects of 5-aminolevulinic acid-mediated photodynamic therapy against oral squamous cell carcinoma / 中华口腔医学杂志

Objective@#To investigate the in vitro and in vivo effects of 5-aminolevulinic acid (5-ALA)-mediated photodynamic therapy against oral squamous cell carcinoma (OSCC) and preliminarily explore the possible mechanisms.@*Methods@#SCC25 cells were divided into the control group (5-ALA of 0 mg/L) and the experimental group (5-ALA of 10, 25, 50, 100 and 150 mg/L). The production of protoporphyrin Ⅸ (PpⅨ) induced by 5-ALA in SCC25 cells was detected using the flow cytometry. SCC25 cells were divided into the control group (5-ALA of 0 mg/L), lazer alone group, 5-ALA alone group (5-ALA of 100 mg/L) and the 5-ALA combined with laser irradiation group (5-ALA of 5, 10, 25, 50 and 100 mg/L), the cytotoxicity of 5-ALA combined with laser irradiation (wave length 635 nm, power density 87 mW/cm2 and laser dose 10.4 J/cm2) was evaluated in SCC25 cells using the methyl thiazolyltetrazolium assay (incubation times of 4, 8 and 12 h in each group) and the induction effect of combination treatment on the cell apoptosis was assessed by the flow cytometry (incubation time of 12 h in each group). The intracellular production of reactive oxygen species (ROS) triggered by 5-ALA combined with laser irradiation was determined using a fluorescence probe method (incubation time of 12 h in each group). A mouse OSCC xenograft model bearing SCC25 tumor was built, and the mice were divided into control group (saline), 5-ALA group (5-ALA of 50 mg/kg) and 5-ALA combined with laser irradiation group (5-ALA of 10, 25 and 50 mg/kg). Antitumor effect of 5-ALA combined with laser irradiation (wave length 635 nm, power density 158 mW/cm2 and laser dose 94.8 J/cm2) was further measured.@*Results@#5-ALA induced the production of PpⅨ in SCC25 cells in a drug concentration (0-150 mg/L)-and incubation time (0-24 h)-dependent manner. When the 5-ALA concentration was 100 mg/L, the intracellular PpⅨ production was in a relatively stable state. Cell viability and apoptosis rate of 5, 10, 25, 50, 100 mg/L 5-ALA combined with laser irradiation are, respectively, (82.3±5.2)%, (3.13±0.38)%; (74.6±9.3)%, (5.38±0.55)%; (38.3±9.7)%, (17.97±2.72)%; (9.2±3.8)%, (24.47±3.37)%; (7.2±0.8)%, (43.01±5.96)%, which indicated that 5-ALA combined with laser irradiation notably inhibited the growth of SCC25 cells and also induced significant cell apoptosis compared with the control group [(96.3±6.0)%, (0.35±0.13)%, P<0.05]. After combination treatment (5-ALA of 5, 10, 25, 50 and 100 mg/L combined with laser irradiation, the mean fluorescence intensity of dichlorofluorescein is (1.46±0.12)×104, (2.16±0.30)×104, (3.57±0.34)×104, (81.70±13.05)×104, (113.00±7.35)×104, respectively, a large amount of ROS was produced in SCC25 cells compared with the control group [(0.96±0.15) ×104, P<0.05], which was in positive correlation with the intracellular PpⅨ content. 5-ALA (concentration of 10, 25 and 50 mg/kg) combined with laser irradiation greatly suppressed the tumor growth in SCC25 tumor-bearing mice compared to the control group (P<0.05).@*Conclusions@#5-ALA-mediated photodynamic therapy can trigger the generation of intracellular ROS that has significant cytotoxicity and apoptosis induction effect, and thus inhibit the tumor growth both in vitro and in vivo.

Preparation of multifunctional nanoscaled red blood cells drug delivery system and its photothermal and photodynamic effects / 国际生物医学工程杂志

Objective To prepare a red blood cells based multifunctional nanoscaled drug delivery system,and to study its in vitro photothermal and photodynamic effects.Methods The indocyanine green (ICG)/doxorubicin (DOX) co-loaded nanoscaled red blood cells (DIRAs) were prepared using an extrusion method.The morphology,particle size,encapsulation efficiency,and stability were determined.The heating related change of particle size was studied using a size and potential tester.The in vitro photothermal effect was studied using an infrared imaging device.The uptake of DIRAs to 4T1 cells was studied using a CLSM examination.The in vitro photodynamic effect was studied using a fluorescence probe and CLSM examination.Results DIRAs were successfully prepared with a uniform and homogeneous size which was about (97.0±20.1) nm.The Zeta potential was about-21.6 mV and the encapsulation efficiency of ICG and DOX were 93.5％ and 95.2％,respectively.The DIRAs had excellent stability within 28 days.This nanoscaled drug delivery system had identical photothermal effect compared to free ICG.The cellular uptake of DOX was significantly improved after the laser irradiation and the photodynamic effect was enhanced.Conclusions The prepared DIRAs have regular shape,suitable particle size,high encapsulation efficiency and high photothermal conversion efficiency.DIRAs can improve the cellular uptake of DOX and enhance the photodynamic efficiency.This biomimetic muhifunctional nano-system could facilitate breast cancer treatment by combining PTT7PDT and chemotherapy.

Preliminary study on transdermal characteristics and sunface anesthetic effects of lidocaine hydrochloride loaded trans-activator of transcription peptide conjugated nano-niosome in animals / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To prepare a new dental topical anesthetics, lidocaine hydrochloride loaded trans-activator of transcription peptide conjugated nano-niosome (LID-TAT-N), and to evaluate its transdermal properties and topical anesthesia effects.</p><p><b>METHODS</b>LID-TAT-N was prepared using reverse-phase evaporation method, and lidocaine loaded conventional liposome (LID-CL) was prepared in the same manner as positive control. The diameter, ζ potential and encapsulation efficiency of LID-TAT-N and LID-CL were measured. The skin permeation of LID-TAT-N was examined, and compared with LID-CL and lidocaine injection (LID-IJ, as negative control), using a Franz diffusion cell mounted with depilated mouse skin in vitro for 12 hours. Each experiment was repeated six times. The anesthetic effect of the new topical anesthetic was investigated on the cornea of rabbits.</p><p><b>RESULTS</b>The mean diameter of LID-TAT-N was smaller than that of LID-CL [(152.7 ± 10.6) nm vs. (259.5 ± 15.5) nm, P < 0.01]. The 12 h cumulative permeation amount was significantly higher in LID-TAT-N group [(1 340.0 ± 97.5) µg · cm(-2)] than those of LID-CL and LID-IJ groups [(1 060.6 ± 80.2), (282.6 ± 65.1) µg · cm(-2), respectively, P < 0.05]. Rabbit corneal reflex results showed that LID-TAT-N had anesthetic effect and the duration of analgesia [(24.8 ± 2.8) min] was also longer than that of LID-IJ [(14.5 ± 2.3) min, P < 0.05].</p><p><b>CONCLUSIONS</b>LID-TAT-N had good transdermal ability, and the advanced skin penetration feature can improve its tropical anesthetic effect.</p>

Percutaneous permeability of lidocaine hydrochloride loaded destran-based niosomes / 天津医药

Objective To study the percutaneous permeability through mouse skin of lidocaine hydrochloride-loaded destran-based niosomes(LID-HLD-BNs)in vitro and in vivo. Methods HPLC was employed to exam lidocaine hydrochlo?ride. Lidocaine hydro-chloride-loaded conventional liposomes (LID-CLs) and lidocaine hydrochloride injection (LID-IJ) were used as control. Isolated mouse skin was added into Franz diffusion cell to evaluate the permeability of LID-HLD-BNs in vitro. Confocal Laser Scanning Microscopy(CLSM)was used to observe the permeation depth of mouse skin in vivo. Re?sults The permeation rate and cumulative permeation amount were significantly higher in LID-HLD-BNs group than those of LID-CLs and LID-IJ groups (P<0.05). CLSM studies also confirmed that HLD-BNs reached deeper layers of the skin. Conclusion LID-HLD-BNs has good transdermal ability.