The Effect of Indocyanine Green Antimicrobial Photothermal/Photodynamic Therapy on the Expression of BCL-2 and BAX Messenger RNA Levels in Human Gingival Fibroblast Cells.

BACKGROUND: Antimicrobial photothermal/photodynamic therapy (PTT/PDT) with indocyanine green (ICG) is an adjuvant therapeutic approach in the treatment of periodontitis. To explore whether PTT/PDT with ICG causes cell death by apoptosis in human gingival fibroblast (HGF) cells, BAX and BCL-2 genes expression as key events for apoptosis were evaluated in this study. MATERIALS AND METHODS: HGF cells were treated with: 1) different concentrations (500-2000 µg/mL) of ICG alone, 2) Diode laser irradiation alone with a fluency of 39.06 J/cm2; 3) PTT/PDT combined different concentrations (500-2000 µg/mL) of ICG with an 808 nm diode laser with a fluency of 39.06 J/cm2, and 4) controls (untreated cells). After that, BAX and BCL-2 messenger RNA levels were evaluated by real-time quantitative reverse transcription PCR. RESULTS: PTT/PDT with 500 µg/mL of ICG caused significant increases in the expression of the BAX gene, with an 8.5-fold increase, which was approximately 7- and 8.5-fold higher than PTT/PDT with ICG for 1500 and 2000 µg/mL of ICG, respectively, indicating induction of apoptosis in HGF cells. ICG (in different test concentrations), diode laser, and PTT/PDT with ICG (1500 and 2000 µg/mL of ICG) treatment displayed insignificant increases in expression levels of BAX (all p>0.05). Our experiments showed an insignificant increase (1.1-1.6-fold) in the expression of BCL-2 after ICG, diode laser, and PTT/PDT with ICG treatment (all p>0.05). CONCLUSIONS: This study suggests that various concentration of ICG can be the diverse expression of BAX responses to PTT/PDT on HGF cells.

Effect of photodynamic therapy based on indocyanine green on expression of apoptosis-related genes in human gingival fibroblast cells.

BACKGROUND: Periodontal diseases refer to inflammation of the gingiva, induction of apoptosis in human gingival fibroblast cells, destruction of the surrounding tissues, and early bone loss resulting in infections due to the pathogenic activity of the microorganisms and the host immune inflammatory responses. Recent investigations have suggested that antimicrobial photodynamic therapy (aPDT) can be an adjunct treatment therapy for periodontal infections. AIM: To prove the lack of side effects of PDT on periodontal tissues, we investigated the expression of BAX and BCL-2 genes that are involved in apoptosis after the PDT on human gingival fibroblast (HGF) cells. MATERIALS AND METHODS: In this study the effect of PDT based on indocyanine green (ICG) as a photosensitizer with the diode laser were tested on the expression of BAX and BCL-2 genes in monolayers of HGF cells. The effects of PDT on the expression of BAX and BCL-2 genes were evaluated by real-time quantitative reverse transcription PCR. RESULTS: The results of the genes expression analysis revealed that ICG-PDT at concentrations 1000µg/mL, induced the significant expression of BAX in HGF cells; however, the laser irradiation as well as ICG showed no significant effects on the expression of these genes. Treatment with ICG alone, laser irradiation and ICG-PDT caused no observable BCL-2 gene expression changes between the tested and control groups. CONCLUSION: Our findings indicate that ICG-PDT at 1000µg/mL of ICG with the exposure time of 60s for the diode laser would appear to be an inducer of apoptosis in HGF at transcriptome level.

Wide distribution of carbapenem resistant Acinetobacter baumannii in burns patients in Iran.

Antimicrobial resistance in carbapenem non-susceptible Acinetobacter baumannii (CNSAb) is a major public health concern globally. This study determined the antibiotic resistance and molecular epidemiology of CNSAb isolates from a referral burn center in Tehran, Iran. Sixty-nine CNSAb isolates were tested for susceptibility to antimicrobial agents using the E test methodology. Multiple locus variable number tandem repeat analysis (MLVA), Multilocus sequence typing (MLST) and multiplex PCR were performed. PCR assays tested for ambler classes A, B, and D ß-lactamases. Detection of ISAba1, characterization of integrons, and biofilm formation were investigated. Fifty-three (77%) isolates revealed XDR phenotypes. High prevalence of bla OXA-23-like (88%) and bla PER-1 (54%) were detected. ISAba1 was detected upstream of bla ADC, bla OXA-23-like and bla OXA51-like genes in, 97, 42, and 26% of isolates, respectively. Thirty-one (45%) isolates were assigned to international clone (IC) variants. MLVA identified 56 distinct types with six clusters and 53 singleton genotypes. Forty previously known MLST sequence types forming 5 clonal complexes were identified. The Class 1 integron (class 1 integrons) gene was identified in 84% of the isolates. The most prevalent (33%) cassette combination was aacA4-catB8-aadA1. The IC variants were predominant in the A. baumannii lineage with the ability to form strong biofilms. The XDR-CNSAb from burned patients in Iran is resistant to various antimicrobials, including tigecycline. This study shows wide genetic diversity in CNSAb. Integrating the new Iranian A. baumannii IC variants into the epidemiologic clonal and susceptibility profile databases can help effective global control measures against the XDR-CNSAb pandemic.