Current Pharmaceutical Biotechnology - Volume 20, Issue 12, 2019

Tissue engineering focuses on developing biological substitutes to restore, maintain or improve tissue functions. The three main components of its application are scaffold, cell and growthstimulating signals. Scaffolds composed of biomaterials mainly function as the structural support for ex vivo cells to attach and proliferate. They also provide physical, mechanical and biochemical cues for the differentiation of cells before transferring to the in vivo site. Collagen has been long used in various clinical applications, including drug delivery. The wide usage of collagen in the clinical field can be attributed to its abundance in nature, biocompatibility, low antigenicity and biodegradability. In addition, the high tensile strength and fibril-forming ability of collagen enable its fabrication into various forms, such as sheet/membrane, sponge, hydrogel, beads, nanofibre and nanoparticle, and as a coating material. The wide option of fabrication technology together with the excellent biological and physicochemical characteristics of collagen has stimulated the use of collagen scaffolds in various tissue engineering applications. This review describes the fabrication methods used to produce various forms of scaffolds used in tissue engineering applications.

Background: Vascular endothelial growth factor (VEGF)-C, -D, and VEGF receptor-3 are proteins characterized as crucial for tumor lymphangiogenesis. It is accompanied by angiogenesis during wound healing, but also in the neoplastic process. The research studies have shown that the lymphatic system plays a key role in the progression of carcinogenesis. Objective: The aim of this study was to evaluate changes in the expression of VEGF-C, VEGF-D and VEGFR-3 in different grades of endometrial cancer (G1-G3). Methods: The study included 45 patients diagnosed with endometrial cancer (G1=17; G2=15; G3=13) and 15 patients without neoplastic changes. The expression of VEGF-C, VEGF-D, and VEGFR-3 was assessed using microarray technique and immunohistochemistry. Statistical analysis was performed using the one-way ANOVA and Tukey's post-hoc test. Results: Statistically significant changes in the expression at the transcriptome level were found only in the case of VEGF-C (G1 vs. C, fold change - FC = -1.15; G2 vs. C, FC = -2.33; G3 vs. C, FC = - 1.68). However, VEGF-D and VEGFR-3 were expressed at the protein level. Analysis of VEGF-D expression showed that the optical density of the reaction product in G1 reached 101.7, while the values in G2 and G3 were 142.7 and 184.4, respectively. For VEGF-R3, the optical density of the reaction product reached the following levels: 72 in control, 118.77 in G1, 145.8 in G2, and 170.9 in G3. Conclusion: An increase in VEGF-D and VEGFR-3 levels may indicate that VEGF-D-dependent processes are intensified along with the dedifferentiation of tumor cells. The lack of VEGF-C expression in endometrial cancer samples may suggest that this tumor is characterized by a different mechanism of metastasis than EMT. Our study emphasizes that when analyzing the metastatic potential of cancer, the expression of more than one factor should be taken into account.

Background: The protective effects of heat shock proteins (Hsps) were studied in some infectious and non-infectious diseases, but their specificity was slightly known in various disorders. Among Hsps, small Hsps (e.g. Hsp27 and Hsp20) have important roles in protein folding and translocation, and also in immunity. Methods: In this study, overexpression of Hsp20 and Hsp27 was performed by transfection of the plasmids encoding Hsp20 and Hsp27 (pEGFP-Hsp20 and pEGFP-Hsp27) into Huh7.5, Hela and Vero cells using Lipofectamine along with heat shock. Then, their anti-herpes simplex virus-1 (HSV-1), anti- human immunodeficiency virus-1 (HIV-1) and anti-hepatitis C virus (HCV) effects, as well as cytotoxicity, were evaluated in vitro, for the first time. Results: Our data showed that simultaneous treatment with Lipofectamine and heat shock augmented the rate of transfection and subsequently the expression of Hsps in these cells. Moreover, overexpression of Hsp20 in HCV-infected Huh7.5 cells, HIV-infected Hela cells and HSV-infected Vero cells reduced the replication of HCV, HIV and HSV, respectively. In contrast, overexpression of Hsp27 significantly decreased HSV replication similar to Hsp20, but it did not affect the replication of HIV and HCV. Conclusion: Generally, Hsp20 was identified as a novel anti-HCV, anti-HSV and anti-HIV agent, but Hsp27 was efficient in the suppression of HSV infection. These Hsps may act through suppression of virus entry and/ or through interaction with viral proteins. Thus, it is necessary to determine their exact mechanisms in the near future.

Background: Bacillus thuringiensis toxins are effective against multiple biological targets such as insects, nematodes, mites, protozoa, and importantly, human cancer cells. One of the main mechanisms by which Cry toxins to trigger cell death is the specific recognition of cadherin-like membrane cell receptors. Objective: This work aimed to assess the cytotoxicity of the Cry1Ab and Cry1Ac toxins from Bacillus thuringiensis in HeLa, cervical cancer cell line, as well as their antitumor activity in mouse models. Methods: We analyzed several biological targets of Cry1Ab and Cry1Ac including erythrocytes, insect larvae, as well as cancer and non-cancer cell lines. The viability of HeLa, SiHa, MCF7 and HaCat cells was assessed by MTT 24 h after the administration of Cry toxins. We also studied apoptosis as a possible cytotoxicity mechanism in HeLa. The capacity of Cry toxins to eliminate tumors in xenograft mouse models was also analyzed. Results: Both toxins, Cry1Ab and Cry1Ac, showed specific cytotoxic activity in HeLa (HPV18+) cervical cancer cell line, with a Cry1Ab LC50 of 2.5 μg/ml, and of 0.5 μg/ml for Cry1Ac. Apoptosis was differentially induced in HeLa cells using the same concentration of Cry1Ab and Cry1Ac toxins. Cry1Ac eliminated 50% of the tumors at 10 μg/ml, and eliminate 100% of the tumors at 30 and 50 μg/ml. Conclusion: Bacillus thuringiensis Cry1A toxins show dual cytotoxic activity, in insects as well as in HeLa cancer cell line.

Background & Objective: The present study was aimed at characterizing the conformational alterations induced in human transferrin, the iron regulatory protein by glyoxal. Since protein aggregation is at the core of many disorders, thus interest in this domain has increased significantly during the past years. Methods: In our present study, the effect of glyoxal was monitored on human transferrin using multispectroscopic and multi-microscopic studies. Results: Intrinsic fluorescence spectroscopy suggested changes in native conformation of human transferrin evident by decreased fluorescence and blue shift in the presence of glyoxal. Further, extrinsic fluorescence was retorted and the results showed the formation of aggregates; apparent by increased Congo red (CR) absorbance, Thioflavin T (ThT) and ANS fluorescence and TEM of human transferrin in the presence of glyoxal. Molecular docking was also employed to see which residues are at core of human transferrin and glyoxal interaction. Reactive oxygen species (ROS) generation assays revealed enhanced ROS levels by human transferrin after treatment with glyoxal. Conclusion: Thus, our study proposes that glyoxal induces the formation of aggregates in human transferrin. These aggregates further generate ROS which are key players in the complications associated with diabetes mellitus, giving our study clinical perspective.

Background & Objective: Corneal endothelial cells (ECD) are characterized by limited regenerative potential, which is additionally impaired in patients with diabetes. This retrospective study included 27 patients aged 58.1±13.6, 16 female and 11 males, who underwent 23-gauge vitrectomy in combination with cataract surgery (phacovitrectomy) and further Ex-PRESS shunt implantation throughout 2013-2017 at St. Barbara Hospital in Sosnowiec, Poland. Methods: In our study, we distinguished 4 periods: initial period; post phacovitrectomy and removal of oil tamponade; and 3 and 12 months post implantation of the Ex-PRESS shunt. Statistical analysis was performed at the level of statistical significance of p<0.05. It included an analysis of variance (ANOVA) and Tukey’s post-hoc test in order to determine the differences in the density of ECD cells/mm2 between the periods of observation. The paired-samples t-Student test was also performed to determine whether the differences in visual acuity values before and after PPV and before and after Ex-PRESS shunt were statistically significant. Results: The initial count of ECD cells was 2381.1±249, which decreased to 1872.8±350.7 cell/mm2 and finally to 1677.9±327 at the endpoint. Differences in the density of ECD cells/mm2 were observed to be statistically significant between the periods: after PPV vs. initial number of ECD (p = 0.000138); before 3 months after Ex-PRESS shunt vs. initial number of ECD (p = 0.000138); 12 months after Ex- PRESS shunt vs. initial number of ECD (p = 0000138). Analyzing the changes in visual acuity, we observed a deterioration both before and 3 months after Ex-PRESS shunt (p = 0.007944) and before and after PPV (p = 0.060334). In turn, correlation analysis indicated that there is a statistically significant, moderate, positive relationship. The relationship between visual acuity after Ex-PRESS shunt and ECD cells/mm2 density turned out to be statistically significant (r = +0.521381; p < 0.05). Conclusion: Regardless of the period of observation and the choice of ophthalmic treatment of diabetic complications, we observed a decrease in the number of ECD cells and a deterioration in visual acuity. It is, therefore, reasonable to provide the patient with complete information about the proposed procedures and to consider the risk-benefit balance.

Objective: The diagnostic sensitivity and specificity of conventional methods for superficial lymph node tuberculosis (LNTB) are not ideal. We evaluated several novel methods including Xpert Mycobacterium tuberculosis/rifampicin (Xpert MTB/RIF) technology, quantitative fluorescence Polymerase Chain Reaction (qPCR) and High-Resolution Melting Curve (HRMC) in the diagnosis of superficial lymph node TB. Methods: Specimens from eighty-one consecutive patients with suspected LNTB and thirteen cases with other lymph node disease were analyzed by Xpert MTB/RIF, qPCR, and HRMC. Results: Among 81 patients with clinical suspicion of LNTB, there were 74 (91.4%) cases positive Mycobacterium tuberculosis Complex (MTBC) of Xpert MTB/RIF, 60 (74%) positive of qPCR, 24 (29.6%) of positive of BACTEC MGIT960 culture, and 13 (16%) cases positive of Roche culture. 38 cases (46.9%) were diagnosed with LNTB. All test methods showed a diagnostic specificity of 100% for LNTB. The sensitivity of molecular biology techniques was significantly higher than that of the traditional diagnostic methods, and Xpert MTB/RIF was the most sensitive diagnostic assay. On Rifampinresistant detection, Xpert MTB/RIF detected three cases (3.7%) with rpoB gene mutation, and Mycobacterium tuberculosis susceptibility testing detected 2 rifampicin-resistant cases (2.4%) which were consistent with Xpert MTB/RIF results. In the Isoniazid-resistant, 7 cases (8.1) of isoniazid resistance mutations (8.1%) were detected by HNC and 1 case was confirmed by Isoniazid susceptibility test. Conclusion: Molecular detection increased the diagnostic sensitivity of LNTB and improved the detection sensitivity for rifampin and isoniazid resistance strain.

Objective: The present study was aimed to evaluate the effect of the aqueous extract of Tinospora cordifolia (AETC) against cyclophosphamide-induced immunosuppression and systemic Candida albicans infection in a murine model. Methods: The protective effect of AETC against cyclophosphamide-induced leukopenia was evaluated by quantitative and qualitative analysis of the leukocytes. The immune-stimulating potential of AETC on macrophages was assessed by determining the levels of secreted cytokines. To determine the direct antifungal activity, AETC or fluconazole was administered to C. albicans infected mice. The efficacy of treatment was assessed by determining the survival rate, kidney fungal burden, the organ index and liver inflammation parameters. Results: Cyclophosphamide administration resulted in substantial depletion of leukocytes, whereas AETC treatment induced the recovery of leukocytes in cyclophosphamide-injected mice. Moreover, AETC treatment of macrophages resulted in enhanced secretion of IFN-γ, TNF-α and IL-1β. C. albicans infected mice treated with AETC at the doses of 50 and 100 mg/kg exhibited 40% and 60% survival rate, whereas the mice treated with fluconazole at a dose of 50 mg/kg showed 20% survival rate. Like survival data, the fungal load was found to be the lowest in the kidney tissues of mice treated with AETC at a dose of 100 mg/kg. Interestingly, mice infected with C. albicans demonstrated improvement in the organ indices and liver functioning after AETC treatment. Conclusion: These results suggest that AETC may potentially be used to rejuvenate the weakened immune system and eliminate systemic candidiasis in mice.

Background: Biodegradable films are appropriate alternatives to synthetic polymers due to their potential to enhance food safety and their function as a carrier for wide a range of food additives especially natural antioxidants. Objective: The aim of this study was to compare the potential antioxidant activities of sodium alginate films containing resveratrol (RES) alone and in combination with Zataria multiflora essential oil (ZEO) using an in vitro model. Methods: At first, the major chemical compositions of ZEO were evaluated by GC/MS. Then, the amount of phenolic compounds of sodium alginate films were evaluated by total phenolic contents assay and antioxidant activities of films were evaluated by 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. Finally, the concentrations of ZEO and RES which showed better antioxidant activities in sodium alginate films were incorporated to films in combination forms to evaluate their synergistic effects. Results: According to gas chromatography-mass spectrometry (GC/MS) analysis, 35 compounds of ZEO were identified and Thymol (37.94%), p-Cymene (9.50%) and 3-Carene (4.98%) were the most important compounds of essential oil, respectively. The results of the radical scavenging evaluations, showed better antioxidant activities of the films containing RES than the films containing ZEO and Butylated hydroxytoluene (BHT). Also, the combined uses of ZEO and RES into alginate films had the synergistic effects (P<0.05). Conclusion: Therefore, it can be concluded that alginate films incorporated with the combination of ZEO and RES is the appropriate option to postpone the oxidative reactions and can be used as natural antioxidant in the food packaging industry.

Due to some inconsistencies in the figures provided by the first author that have come to light, and after a thorough investigation we would like to retract our paper: “Low doses of CPS49 and flavopiridol combination as potential treatment for advanced prostate cancer. By: Zalazar F, De Luca P, Gardner K, Figg WD, Meiss R, Spallanzani RG, Vallecorsa P, Elguero B, Cotignola J, Vazquez E, De Siervi A. Curr. Pharm. Biotechnol., 2015, 16(6), 553-63. Submission of a manuscript to the respective journals implies that all authors have read and agreed to the content of the Copyright Letter or the Terms and Conditions. As such this article represents a severe abuse of the scientific publishing system. Bentham Science Publishers takes a very strong view on this matter and apologizes to the readers of the journal for any inconvenience this may cause.