Abstract: BODIPY dyes tend to be highly fluorescent, but their emissions can be attenuated by adding substituents with appropriate oxidation potentials. Substituents like these have electrons to feed into photoexcited BODIPYs, quenching their fluorescence, thereby generating relatively long-lived triplet states. Singlet oxygen is formed when these triplet states interact with (3)O(2). In tissues, this causes cell damage in regions that are illuminated, and this is the basis of photodynamic therapy (PDT). The PDT agents that are currently approved for clinical use do not feature BODIPYs, but there are many reasons to believe that this situation will change. This review summarizes the attributes of BODIPY dyes for PDT, and in some related areas.
Abstract: Strategy, Management and Health Policy Enabling Technology, Genomics, Proteomics Preclinical Research Preclinical Development Toxicology, Formulation Drug Delivery, Pharmacokinetics Clinical Development Phases I-III Regulatory, Quality, Manufacturing Postmarketing Phase IV This study assessed the in vivo antitumor efficacy of a polypeptide-based poly-L-glutamic acid-gemcitabine conjugate (PG-G). PG-G was synthesized by conjugating gemcitabine to poly-L-glutamic acid by a carbodiimide reaction. PG-G was evaluated for its in vivo antitumor efficacy and toxicity using 4T1 murine breast tumor-bearing mice. The antitumor effects of PG-G were superior to those of unconjugated gemcitabine in both single and four-consecutive dosing studies. Tumor regression was observed within 1 day after PG-G administration and continued for 45 days. Thereafter, tumors grew at a slower rate compared with the unconjugated gemcitabine treatment group and other control groups. The main toxicity observed from the Berlin test was an apparent reversible weight loss of 1012%. The unconjugated gemcitabine treatment group also demonstrated a similar, but reduced, weight loss trend. The present study demonstrates that the PG-G formulation exhibits a significant antitumor activity in the aspects of tumor growth inhibition and shrinkage that is more robust than the parent drug and other control groups. Thus, the PG-G dose regimen may be optimized to minimize side effects and render it a potential anticancer therapeutic.
Abstract: There is a great diversity of protein samples types and origins, therefore the optimal procedure for each sample type must be determined empirically. In order to obtain a reproducible and complete sample presentation which view as many proteins as possible on the desired 2DE gel, it is critical to perform additional sample preparation steps to improve the quality of the final results, yet without selectively losing the proteins. To address this, we developed a general method that is suitable for diverse sample types based on phenolchloroform extraction method (represented by TRI reagent). This method was found to yield good results when used to analyze human breast cancer cell line (MCF-7), Vibrio cholerae, Cryptocaryon irritans cyst and liver abscess fat tissue. These types represent cell line, bacteria, parasite cyst and pus respectively. For each type of samples, several attempts were made to methodically compare protein isolation methods using TRI-reagent Kit, EasyBlue Kit, PRO-PREPâ„¢ Protein Extraction Solution and lysis buffer. The most useful protocol allows the extraction and separation of a wide diversity of protein samples that is reproducible among repeated experiments. Our results demonstrated that the modified TRI-reagent Kit had the highest protein yield as well as the greatest number of total proteins spots count for all type of samples. Distinctive differences in spot patterns were also observed in the 2DE gel of different extraction methods used for each type of sample.
Abstract: To enhance the stability of the anticancer drug gemcitabine (2'-deoxy-2',2'-difluorocytidine), it was conjugated to poly-l-glutamic acid (PG-H) via a carbodiimide reaction. The synthesised poly-l-glutamic acid-gemcitabine (PG-G) was purified and characterised by using SDS-PAGE to estimate its molecular weight, HPLC to determine its purity and degree of drug loading, and NMR to elucidate the structure. In vitro aqueous hydrolytic studies showed that the gemcitabine release from the polymeric drug conjugate was pH dependent, and that the conjugation to PG-H improved its stability in human plasma. The release of the bound gemcitabine from PG-G in plasma was mediated by a hydrolytic process. It began with a lag phase, followed by linear release between 12 and 48h, and reached equilibrium at 72h with 51% of the gemcitabine released. In vitro cytotoxicity studies using MCF-7 and MDA-MB-231 human mammary cancer cells, as well as human dermal fibroblasts (HDF), showed that PG-G displayed a lower dose dependent cytotoxic effect with respect to the parent drug gemcitabine. On the other hand, in 4T1 mouse mammary tumour cells, PG-G and gemcitabine showed similar toxicities. Gemcitabine was more than likely released hydrolytically from PG-G and taken up by MCF-7, MDA-MB-231 and HDF, whereas both released gemcitabine and PG-G were taken up by 4T1 to mediate the observed cytotoxicities. The improved stability and extended sustained release profile may render PG-G a potential anticancer prodrug.
Abstract: Aim: The aim of the present study was to investigate the effectiveness of transforming growth factor (TGF)-beta 1 antisense oligodeoxynucleotides (ODN) in ameliorating deteriorated kidney function in rats with puromycin-induced chronic renal failure (CRF). Methods: Saline, puromycin, puromycin+TGF-beta 1 antisense ODN or puromycin+scrambled ODN were administered to unilaterally nephrectomized rats. Renal hemodynamic and excretory measurements were taken in the anaesthetized rats that had undergone surgical procedure. Results: It was observed that in the CRF rats, there was a marked reduction in the renal blood flow (RBF), glomerular filtration rate (GFR), severe proteinuria, and almost 6-fold increased fractional excretion of sodium (FE Na+) as compared to that in the control rats (all P < 0.05). It was further observed that in the CRF rats, the treatment with TGF-beta 1 antisense, but not scrambled ODN, markedly attenuated the reduction of RBF, GFR, and proteinuria and markedly prevented the increase of the FE Na+ (all P < 0.05). In addition, the renal hypertrophy in the CRF group (P < 0.05 vs non-renal failure control) was markedly attenuated after treatment with TGF-1 antisense ODN (P < 0.05). Focal segmental glomerulosclerosis was evident only in the untreated and scrambled ODN-treated CRF groups. An interesting observation of this study was that in the CRF rats, although there was marked attenuating and preventive effects of the TGF-beta 1 antisense ODN on the deteriorated renal functions, the antisense treatment did not cause any marked change in the renal expression of TGF-beta 1 at the protein level. Conclusion: Collectively, the data obtained suggests that TGF-beta 1 antisense ODN possesses beneficial effects in puromycin-induced chronic renal failure and that the deterioration in morphology and impaired renal function in this pathological state is in part dependent upon the action of TGF-beta 1 within the kidney.
Abstract: An antisense oligodeoxynucleotide (As-ODN) to the 3' untranslated region of the mRNA sequence expressing the intracellular adhesion molecule-1 (ICAM-1) was employed to determine ICAM-1's role in renal ischaemia-reperfusion injury in the rat. Wistar-Kyoto rats receiving i.v. either lipofectin-As-ODN (As-ODN group), lipofectin-reverse ODN (Rv-ODN group) or lipofectin (ischaemia control group) 8 h prior to study were anaesthetized and subjected to 30 min of renal artery occlusion. Renal haemodynamic and excretory parameters were monitored before and after renal ischaemia. On termination of the study renal tissue was subjected to histological and Western blot analysis. Renal blood flow decreased in the 3 h post-ischaemia period in the ischaemia control and Rv-ODN groups, but was maintained in the As-ODN group. Glomerular filtration rate was depressed initially but gradually increased to 10% above basal levels in the ischaemia control and Rv-ODN groups, but was below basal levels (20%) in the As-ODN group. There was a three- to fourfold increase in sodium and water excretion following ischaemia in the ischaemia control and reverse-ODN groups but not in the As-ODN treated group. The As-ODN ameliorated the histological evidence of ischaemic damage and reduced ICAM-1 protein levels to a greater extent in the medulla than cortex. These observations suggested that in the post-ischaemic period afferent and efferent arteriolar tone was increased with a loss of reabsorptive capacity which was in part due to ICAM-1. The possibility arises that the action of ICAM-1 at vascular and tubular sites in the deeper regions of the kidney contributes to the ischaemia-reperfusion injury.
