Clinical efficacy and safety of two different hematoporphyrin monomethyl ether-mediated photodynamic therapy regimen in Chinese children with port-wine stain

Hematoporphyrin monomethyl ether-photodynamic therapy (HMME-PDT) has achieved encouraging clinical outcomes in adult port-wine stain (PWS). Optimal treatment option for children with PWS was minimal. To compare whether the clinical effectiveness of HMME-PDT with the 5-min (fast) administration treatment regimen (FATR) was better than the 20-min (slow) administration treatment regimen (SATR) for PWS of children in vivo and in vitro. Thirty-four children with PWS were divided into two groups including FATR and SATR. The two groups received three times HMME-PDT, respectively. Treatment efficacy and safety were evaluated in vivo and in vitro. Erythema index (EI) was used to evaluate the clinical outcomes. Both FATR and SATR were effective and safe in children with PWS after HMME-PDT. There were significance differences between the two groups in reductions of EI after the second treatment (p < 0.001) and the third treatment (p < 0.001) with HMME-PDT. The serum HMME concentration reach the peak level at short time compare with SATR group. A significance increased superoxide levels were observed in FATR group compare to SATR groups in vitro (p < 0.05). Our study suggested that HMME-PDT was effective and safe for children with PWS, the therapy regimen with FATR was better in clinical efficacy than that of the SATR.

Photosensitizers Dispersed on Nanosized Triterpenoid Matrix with Deaggregation-Enhanced Singlet Oxygen Production

Aggregation-caused quenching (ACQ) effects of photosensitizers severely cut down the generation of quantum yield of singlet oxygen (¹O₂) for effective photodynamic therapy (PDT). Herein, we accomplish a deaggregation-enhanced ¹O₂ production strategy by the noncovalent coordination of a clinically applied triterpenoid oleanolic acid (OA) and hematoporphyrin (Hp) via one-step self-assembly, forming a nanosensitizer OH, in which Hp is interspersed on the surface of the OA matrix in a face-to-face manner. The scattered arrangement of Hp held by the OA matrix decreases the π-π aggregation in Hp, leading to a 3.7-fold boost in the intracellular ¹O₂ yield and high phototoxicity in vitro and in vivo. Moreover, the biologically active OA enables OH to display excellent cellular uptake efficiency (increase by 36-fold), deep tumor penetration, and synergistic antitumor outcome at a low dose. Thus, this simple strategy paves the way for the green development of efficient photosensitizers.

Docetaxel prodrug and hematoporphyrin co-assembled nanoparticles for anti-tumor combination of chemotherapy and photodynamic therapy

To realize the synergistic anti-tumor effect of chemotherapy and photodynamic therapy, the mono sulfide-modified docetaxel (DTX) prodrugs (DSD) provided by our laboratory and hematoporphyrin (HP) were used to physically prepare co-assembled nanoparticles (DSD/HP NPs) by nano-precipitation. For the first time, this study showed its characteristics, in vitro anti-tumor activity, pharmacokinetic behavior in rats, in vivo distribution, and pharmacodynamic effects on 4T1 tumor-bearing Bal b/c mice. DSD/HP NPs optimized by single-factor and response surface optimization had several distinct characteristics. First, it had dark purple appearance with particle size of 105.16 ± 1.24 nm, PDI of 0.168 ± 0.15, entrapment efficiency and drug loading of DSD and HP in DSD/HP NPs of 96.27 ± 1.03% and 97.70 ± 0.20%, 69.22 ± 1.03% and 20.03 ± 3.12%, respectively. Second, it had good stability and could release DTX and HP slowly in the media of pH 7.4 PBS with 10 mM DTT (H₂O₂). Moreover, DSD/HP NPs along with NiR treatment significantly inhibited 4T1 cells proliferation, and induced more reactive oxygen species and cells apoptosis. In vivo pharmacokinetic and pharmacodynamic studies showed that DSD/HP NPs could prolong the drug circulation time in rats, increase drug distribution in tumor site, obviously inhibit tumor growth, and decrease the exposure of drug to normal tissues. Therefore, DSD/HP NPs as a promising co-assembled nano-drug delivery system could potentially improve the therapeutic efficiency of chemotherapeutic drug and achieve better anti-tumor effects due to the combination of chemotherapy and photodynamic therapy.

Lipocalin Blc is a potential heme-binding protein

Lipocalins are a superfamily of functionally diverse proteins defined by a well-conserved tertiary structure despite variation in sequence. Lipocalins bind and transport small hydrophobic molecules in organisms of all kingdoms. However, there is still uncertainty regarding the function of some members of the family, including bacterial lipocalin Blc from Escherichia coli. Here, we present evidence that lipocalin Blc may be involved in heme binding, trans-periplasmic transport, or heme storage. This conclusion is supported by a cocrystal structure, mass-spectrometric data, absorption titration, and in silico analysis. Binding of heme is observed at low micromolar range with one-to-one ligand-to-protein stoichiometry. However, the absence of classical coordination to the iron atom leaves the possibility that the primary ligand of Blc is another tetrapyrrole.

Preparation, characterization, and sonodynamic antitumor effect of the folate receptor targeted FA-EN-β-CD containing hematoporphyrin in vitro

To improve water solubility, reduce phototoxicity and increase the tumor-targeting ability of hematoporphyrin (Hp) as a sonosensitizer for sonodynamic therapy under ultrasonic conditions, a novel folate receptor (FR)-targeted, folate-conjugated ethylenediamine-β-cyclodextrin (FA-EN-β-CD) containing Hp (FA-EN-β-CD-Hp) was constructed. β-Cyclodextrin containing Hp (β-CD-Hp) was also established as a nontargeted control. The inclusion efficiencies of Hp in FA-EN-β-CD-Hp and β-CD-Hp were determined to be 90.4 ± 2.7% (wt/wt) and 92.5 ± 3.4% (wt/wt), respectively. Growth inhibition rates in HepG-2 cells in vitro were assessed upon ultrasound exposure. The results indicated that the growth inhibition rates of FA-EN-β-CD-Hp, β-CD-Hp, and F-Hp (Hp: 150 μg/ml) reached 96.4 ± 3.6%, 53.4 ± 3.4%, and 48.2 ± 2.8%, respectively. These results indicated that FA-EN-β-CD-Hp is a promising drug delivery system in the field of sonodynamic cancer therapy.

Clinical Comparison of Two Photosensitizers for Oral Cavity Decontamination

OBJECTIVE

In this study, we aim to compare the photodynamic inactivation (PDI) effects of two different photosensitizers (PS), Photogem^® and Natural Curcumin, irradiated with light-emitted diodes (LED) at 630 and 450 nm, respectively.

BACKGROUND

The current antimicrobial mouthwash for oral hygiene has several drawbacks. In this context, PDI is an alternative technique to inactivate pathogenic microbes in mucosa and in periodontal tissue. Furthermore, there are numerous infectious diseases that may affect the oral cavity, motivating the use of PDI in dentistry.

METHODS

The volunteers (n = 50) were randomize separated into five experimental groups (n = 5) for each PS: water control, PS control, light control, and two PS concentrations (25 and 100 mg/L). Each patient underwent mouthwash solution containing the PS before illumination procedure that was performed with an LED device. For microbial decontamination evaluation, the saliva was collected three times: before (T0), immediately after (T1), and 24 h after the illumination procedure (T2). After that, the difference between the colony forming units (CFU) for each volunteer was compared.

RESULTS

The results show that regardless of PS and treatment applied, there was microbial reduction immediately after PDI, however, after 24 h only Natural Curcumin still presents a reduction. For Photogem after 24 h, the microorganism returns to the original CFU.

CONCLUSIONS

Immediately after PDI, both PS have the same efficiency, nevertheless the Natural Curcumin still has an efficacy after 24 h and also is a more viable photosensitizer. In addition, the results indicate that PDI can be a promised technique used for microbial reducing for the oral cavity.

Size-Dependent Photodynamic Anticancer Activity of Biocompatible Multifunctional Magnetic Submicron Particles in Prostate Cancer Cells

In this study, newly designed biocompatible multifunctional magnetic submicron particles (CoFe₂O₄-HPs-FAs) of well-defined sizes (60, 133, 245, and 335 nm) were fabricated for application as a photosensitizer delivery agent for photodynamic therapy in cancer cells. To provide selective targeting of cancer cells and destruction of cancer cell functionality, basic cobalt ferrite (CoFe₂O₄) particles were covalently bonded with a photosensitizer (PS), which comprises hematoporphyrin (HP), and folic acid (FA) molecules. The magnetic properties of the CoFe₂O₄ particles were finely adjusted by controlling the size of the primary CoFe₂O₄ nanograins, and secondary superstructured composite particles were formed by aggregation of the nanograins. The prepared CoFe₂O₄-HP-FA exhibited high water solubility, good MR-imaging capacity, and biocompatibility without any in vitro cytotoxicity. In particular, our CoFe₂O₄-HP-FA exhibited remarkable photodynamic anticancer efficiency via induction of apoptotic death in PC-3 prostate cancer cells in a particle size- and concentration-dependent manner. This size-dependent effect was determined by the specific surface area of the particles because the number of HP molecules increased with decreasing size and increasing surface area. These results indicate that our CoFe₂O₄-HP-FA may be applicable for photodynamic therapy (PDT) as a PS delivery material and a therapeutic agent for MR-imaging based PDT owing to their high saturation value for magnetization and superparamagnetism.

Enhanced sonodynamic antitumor effect of ultrasound in the presence of nonsteroidal anti-inflammatory drugs

The antitumor effects of non-steroidal anti-inflammatory drugs, tenoxicam and piroxicam, against sarcoma 180 cells cultured in 7-week-old male mice were examined in vitro under ultrasonic irradiation. The survival rate of tumor cells when tenoxicam or piroxicam was added to sarcoma 180 suspension under ultrasonic irradiation was significantly lower than that when ultrasound alone was applied. Furthermore, when L-histidine, a scavenger of singlet oxygen and hydroxyl radical, or D-mannitol, a scavenger of hydroxyl radical, was used concurrently, the survival rate of tumor cells was significantly higher with L-histidine. From the above findings, it is surmised that tenoxicam and piroxicam increase the antitumor effects of ultrasound by increasing the production of singlet oxygen and other active oxygen species.

Enhancement of the antitumor effect by combined use of high-energy shock waves and ATX-70

The antitumor effects of high-energy shock waves (HESW) in combination with ATX-70 [a gallium-porphyrin complex, 2,4-bis(1-decyloxyethyl)-Ga(III)-1,3,5,8-tetramethylporphyrin++ +-6, 7-dipropionyl diaspartic acid [sequence: see text] were investigated. In vitro, the cell damage to mouse MH134 hepatoma after HESW treatment was enhanced by adding ATX-70. In vivo, HESW and ATX-70 combination therapy inhibited cell growth. However, neither HESW treatment alone nor ATX-70 treatment alone inhibited cell growth. These results imply that the antitumor effects of HESW and ATX-70 combined therapy are caused by activation of ATX-70 by HESW.

Mechanism of cell damage by ultrasound in combination with hematoporphyrin

The mechanism of cell damage by ultrasound in combination with hematoporphyrin was studied. Mouse sarcoma 180 cell suspensions were exposed to ultrasound for up to 60 s in the presence and absence of hematoporphyrin, with and without active oxygen scavengers. The cell damage enhancement by hematoporphyrin was suppressed by adding histidine but not by mannitol. The enhancement was doubled in rate by substitution of deuterium oxide medium for normal water. Sonoluminescence was produced in a saline solution under similar acoustic conditions and observed to have spectral components that can excite hematoporphyrin molecules. These results suggest that cell damage enhancement is probably mediated via singlet oxygen generated by ultrasonically activated hematoporphyrin.

Synergistic effect of ultrasound and hematoporphyrin on sarcoma 180

The antitumor effects of combined use of ultrasound (US) and a photosensitizer, hematoporphyrin (Hp), were determined in mice bearing sarcoma 180. In order to find the optimum timing of the US irradiation after the administration of Hp, the Hp concentrations in the tumor and in the plasma were determined and were analyzed pharmacokinetically. Antitumor effects were evaluated by measuring the tumor size and the tumor weight. Hp alone showed no antitumor effect but US alone showed a slight antitumor effect. The combined treatment with US and Hp showed marked synergistic effects on sarcoma 180 (inhibition ratio was 74% of the control). From these results, the enhancement of antitumor effect is thought to be caused by the sensitization of tumor cells to US mediated by Hp.

Hematoporphyrin as a sensitizer of cell-damaging effect of ultrasound

Mouse sarcoma 180 or rat ascites hepatoma (AH) 130 cells were exposed to ultrasound (US; 1.27, 2.21 and 3.18 W/cm2; 1.92 MHz) for up to 60 s in vitro in the presence or absence of hematoporphyrin (Hp; 10, 25 and 50 micrograms/ml). The cell-damaging effects of treatments were determined by means of the Trypan Blue dye exclusion test. Hp alone did not show any cell-damaging effect, whereas US alone damaged 30 and 50% of sarcoma and AH 130 cells, respectively, at the maximum intensity for 60 s. In the presence of 50 micrograms/ml Hp, US damaged 99 and 95% of the above tumor cells, respectively. These results show that Hp increased the sensitivity of tumor cells to US.