Second-generation piperazine derivatives as promising radiation countermeasures.

The increasing threat of nuclear incidents and the widespread use of ionizing radiation (IR) in medical treatments underscore the urgent need for effective radiation countermeasures. Despite the availability of compounds such as amifostine, their clinical utility is significantly limited by adverse side effects and logistical challenges in administration. This study focuses on the synthesis and evaluation of novel piperazine derivatives as potential radioprotective agents, with the aim of overcoming the limitations associated with current countermeasures. We designed, synthesized, and evaluated a series of 1-(2-hydroxyethyl)piperazine derivatives. The compounds were assessed for cytotoxicity across a panel of human cell lines, and for their radioprotective effects in the MOLT-4 lymphoblastic leukemia cell line and in peripheral blood mononuclear cells (PBMCs) exposed to gamma radiation. The radioprotective efficacy was further quantified using the dicentric chromosome assay (DCA) to measure DNA damage mitigation. Among the synthesized derivatives, compound 6 demonstrated the most significant radioprotective effects in vitro, with minimal cytotoxicity across the tested cell lines. Compound 3 also showed notable efficacy, particularly in reducing dicentric chromosomes, thus indicating its potential to mitigate DNA damage from IR. Both compounds exhibited superior safety profiles and effectiveness compared to amifostine, suggesting their potential as more viable radioprotective agents. This study highlights the development of novel piperazine derivatives with promising radioprotective properties. Compound 6 emerged as the leading candidate, offering an optimal balance between efficacy and safety, with compound 3 also displaying significant potential. These findings support the further development and clinical evaluation of these compounds as safer, and more effective radiation countermeasures.

Association of the combined parameters including the frequency of primary cilia, PD-L1, Smoothened protein, membranous ß-catenin and cytoplasmic ß-catenin expression with the outcome of patients with clear cell renal cell carcinoma.

AIMS: The objective of this study was to investigate the association and combined prognostic significance of the PD-L1, Smoothened protein and ß-catenin expressions in patients with clear cell renal cell carcinoma (ccRCC). METHODS: The PD-L1, Smoothened protein and ß-catenin expression were evaluated in 104 ccRCC patients. All studied tumor samples were acquired from nephrectomy specimens of primary tumors and not from biopsies or metastases. An indirect immunohistochemistry using polyclonal rabbit anti-Smoothened antibody, monoclonal mouse anti-human ß-catenin-1 antibody, immunohistochemical assay PD-L1 28-8 pharmDx using monoclonal rabbit anti-PD-L1 antibody and anti-VHL (C- terminal) rabbit antibody was used. Immunohistochemistry was scored semiquantitavely. RESULTS: Median overall survival (OS) was significantly better in patients with lower PD-L1 expression (≤5%), Smoothened protein (SMO) expression (<5%) or cytoplasmic ß-catenin expression (≤75%) than in patients with higher expressions of these biomarkers (P<0.001, P=0.047, and P<0.001, respectively). Membranous ß-catenin showed an opposite effect with its lower expression (≤75%) being associated with longer OS (P=0.020). There was significant association between PD-1 and PD-L1 expression (P=0.007) and significant association of tumor grade (WHO 2016) with membranous ß-catenin (P<0.001), cytoplasmic ß-catenin (P=0.005), pVHL (P=0.042), PD-L1 (P=0.049) and PD-1 (P=0.028) expression. CONCLUSION: The present study provides the first data on the potential association and combined prognostic significance of frequency of primary cilia, PD-L1, Smoothened protein and ß-catenin expression with the outcome in clear cell renal cell carcinoma.

Looking for the phoenix: the current research on radiation countermeasures.

PURPOSE: Ionizing radiation (IR) is widely applied in radiotherapy for the treatment of over 50% of cancer patients. IR is also intensively used in medical diagnostics on a daily basis in imaging. Moreover, recent geopolitical events have re-ignited the real threat of the use of nuclear weapons. Medical radiation countermeasures represent one of the effective protection strategies against the effects of IR. The aim of this review was to summarize the most commonly used strategies and procedures in the development of radiation countermeasures and to evaluate the current state of their research, with a focus on those in the clinical trial phase. METHODS: Clinical trials for this review were selected in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement. The search was performed in the clinicaltrials.gov database as of May 2022. RESULTS: Our search returned 263 studies, which were screened and of which 25 were included in the review. 10 of these studies had been completed, 3 with promising results: KMRC011 increased G-CSF, IL-6, and neutrophil counts suggesting potential for the treatment of hematopoietic acute radiation syndrome (H-ARS); GC4419 reduced the number of patients with severe oral mucositis and its duration; the combination of enoxaparin, pentoxifylline, and ursodeoxycholic acid reduced the incidence of focal radiation-induced liver injury. CONCLUSION: The agents discovered so far show significant side effects or low efficacy, and hence most of the tested agents terminate in the early stages of development. In addition, the low profitability of this type of drug demotivates the private sector to invest in such research. To overcome this problem, there is a need to involve more public resources in funding. Among the technological opportunities, a deeper use of in silico approaches seems to be prospective.

Favorable prognostic significance of membranous ß-catenin expression and negative prognostic significance of cytoplasmic ß-catenin expression in pancreatic cancer.

The aim of this study was to investigate the prognostic significance of membranous ß-catenin and cytoplasmic ß-catenin expression in pancreatic cancer patients (pts). One hundred pts with histologically verified exocrine pancreatic ductal adenocarcinoma were retrospectively studied. The membranous ß-catenin, cytoplasmic ß-catenin, and cell nucleus ß-catenin expression were immunohistochemically evaluated. The expression of membranous ß-catenin was <5% in none of the pts, 5-25% in one patient, 26-50% in 2 pts, 51-75% in 14 pts, and >75% in 81 pts. The expression of cytoplasmic ß-catenin was <5% in 34 pts, 5-25% in 42 pts, 26-50% in 18 pts, 51-75% in 3 pts, and >75% in one patient. The expression of ß-catenin in the cell nucleus was negative in all pts. At the time of the last follow-up, 21 pts were alive and 79 pts had died. Median OS was 1.3 (0.4-2.3) years in pts with membranous ß-catenin expression ≤75% and 1.7 (1.3-2.1) years in pts with membranous ß-catenin expression >75% (p=0.045). Median OS was (1.3-2.0) 1.6 years in pts with cytoplasmic ß-catenin expression ≤25% and 0.9 (0.5-1.2) years in pts with cytoplasmic ß-catenin expression >25% (p=0.040). In the univariate Cox proportional hazard models HR (95% CI) was 0.556 (0.311-0.995) in pts with membranous ß-catenin expression >75% (p=0.048) and 2.200 (1.216-3.980) in pts with cytoplasmic ß-catenin expression >25% (p=0.009). The present results indicate a favorable prognostic significance of membranous ß-catenin expression in pancreatic cancer.

Mitigation of Ionizing Radiation-Induced Gastrointestinal Damage by Insulin-Like Growth Factor-1 in Mice.

Purpose: Insulin-like growth factor-1 (IGF-1) stimulates epithelial regeneration but may also induce life-threatening hypoglycemia. In our study, we first assessed its safety. Subsequently, we examined the effect of IGF-1 administered in different dose regimens on gastrointestinal damage induced by high doses of gamma radiation. Material and methods: First, fasting C57BL/6 mice were injected subcutaneously with IGF-1 at a single dose of 0, 0.2, 1, and 2 mg/kg to determine the maximum tolerated dose (MTD). The glycemic effect of MTD (1 mg/kg) was additionally tested in non-fasting animals. Subsequently, a survival experiment was performed. Animals were irradiated (60Co; 14, 14.5, or 15 Gy; shielded head), and IGF-1 was administered subcutaneously at 1 mg/kg 1, 24, and 48 h after irradiation. Simultaneously, mice were irradiated (60Co; 12, 14, or 15 Gy; shielded head), and IGF-1 was administered subcutaneously under the same regimen. Jejunum and lung damage were assessed 84 h after irradiation. Finally, we evaluated the effect of six different IGF-1 dosage regimens administered subcutaneously on gastrointestinal damage and peripheral blood changes in mice 6 days after irradiation (60Co; 12 and 14 Gy; shielded head). The regimens differed in the number of doses (one to five doses) and the onset of administration (starting at 1 [five regimens] or 24 h [one regimen] after irradiation). Results: MTD was established at 1 mg/kg. MTD mitigated lethality induced by 14 Gy and reduced jejunum and lung damage caused by 12 and 14 Gy. However, different dosing regimens showed different efficacy, with three and four doses (administered 1, 24, and 48 h and 1, 24, 48, and 72 h after irradiation, respectively) being the most effective. The three-dose regimens supported intestinal regeneration even if the administration started at 24 h after irradiation, but its potency decreased. Conclusion: IGF-1 seems promising in the mitigation of high-dose irradiation damage. However, the selected dosage regimen affects its efficacy.

Hyaluronic Acid: Known for Almost a Century, but Still in Vogue.

Hyaluronic acid (HA) has a special position among glycosaminoglycans. As a major component of the extracellular matrix (ECM). This simple, unbranched polysaccharide is involved in the regulation of various biological cell processes, whether under physiological conditions or in cases of cell damage. This review summarizes the history of this molecule's study, its distinctive metabolic pathway in the body, its unique properties, and current information regarding its interaction partners. Our main goal, however, is to intensively investigate whether this relatively simple polymer may find applications in protecting against ionizing radiation (IR) or for therapy in cases of radiation-induced damage. After exposure to IR, acute and belated damage develops in each tissue depending upon the dose received and the cellular composition of a given organ. A common feature of all organ damage is a distinct change in composition and structure of the ECM. In particular, the important role of HA was shown in lung tissue and the variability of this flexible molecule in the complex mechanism of radiation-induced lung injuries. Moreover, HA is also involved in intermediating cell behavior during morphogenesis and in tissue repair during inflammation, injury, and would healing. The possibility of using the HA polymer to affect or treat radiation tissue damage may point to the missing gaps in the responsible mechanisms in the onset of this disease. Therefore, in this article, we will also focus on obtaining answers from current knowledge and the results of studies as to whether hyaluronic acid can also find application in radiation science.

A Beginner's Introduction to Skin Stem Cells and Wound Healing.

The primary function of the skin is that of a physical barrier against the environment and diverse pathogens; therefore, its integrity is essential for survival. Skin regeneration depends on multiple stem cell compartments within the epidermis, which, despite their different transcriptional and proliferative capacity, as well as different anatomical location, fall under the general term of skin stem cells (SSCs). Skin wounds can normally heal without problem; however, some diseases or extensive damage may delay or prevent healing. Non-healing wounds represent a serious and life-threatening scenario that may require advanced therapeutic strategies. In this regard, increased focus has been directed at SSCs and their role in wound healing, although emerging therapeutical approaches are considering the use of other stem cells instead, such as mesenchymal stem cells (MSCs). Given its extensive and broad nature, this review supplies newcomers with an introduction to SSCs, wound healing, and therapeutic strategies for skin regeneration, thus familiarizing the reader with the subject in preparation for future in depth reading.

A novel class of small molecule inhibitors with radioprotective properties.

The goal of this study was to develop novel radioprotective agents targeting the intrinsic apoptotic pathway and thus decreasing the radiation-induced damage. For that purpose, we designed, synthesized and analyzed ten new compounds based on the 1-(4-(2-hydroxyethyl)piperazin-1-yl)-3-phenoxypropan-2-ol leading structure. The cytotoxicity of the newly synthesized substances was tested in vitro on cell lines derived from different progenitor cells by WST-1 proliferation assay. MTT test was utilized to assess half-maximal inhibitory concentrations and maximum tolerated concentrations of novel compounds in A-549 cells. Screening for radioprotective properties was performed using flow-cytometry in MOLT-4 cells exposed to 60Co ionizing gamma radiation. Selected candidates underwent in vivo testing in C57Bl/6 J mice having a positive impact on their immunological status. In summary, we report here promising compounds with radioprotective effect in vivo.

Substituted Piperazines as Novel Potential Radioprotective Agents.

The increasing risk of radiation exposure underlines the need for novel radioprotective agents. Hence, a series of novel 1-(2-hydroxyethyl)piperazine derivatives were designed and synthesized. Some of the compounds protected human cells against radiation-induced apoptosis and exhibited low cytotoxicity. Compared to the previous series of piperazine derivatives, compound 8 exhibited a radioprotective effect on cell survival in vitro and low toxicity in vivo. It also enhanced the survival of mice 30 days after whole-body irradiation (although this increase was not statistically significant). Taken together, our in vitro and in vivo data indicate that some of our compounds are valuable for further research as potential radioprotectors.

INVESTIGATION OF THE RADIOPROTECTIVE EFFECT OF ORTHOVANADATE IN MICE AFTER TOTAL BODY IRRADIATION.

The increasing risk of acute large-scale exposure of ionising irradiation on the population underlines the necessity of developing effective radioprotective and mitigating agents. The aim of this work was to investigate the effect of sodium orthovanadate pre-treatment on mice exposed to high doses of gamma rays (from 5 to 13 Gy). The determination of median lethal dose within 30 days confirmed that orthovanadate applied to total-body-irradiated mice intra-peritoneally has a radioprotective but not a mitigating effect. With orthovanadate pre-treatment, the composition of cellularity in the bone marrow improved substantially and the main lymphocyte populations restored during the first month after irradiation. These findings contribute to 'gap-filling' in radioprotective effects and demonstrate the importance of haematological parameters in radiation-response prediction.

Negative prognostic significance of primary cilia, CD8+ tumor infiltrating lymphocytes and PD1+ cells expression in clear cell renal cancer.

PURPOSE: The aim of this study was to investigate the potential association and combined prognostic significance of the frequency of primary cilia (PC), programmed cell death protein-1 receptor (PD1) and CD8+ tumor infiltrating lymphocytes (TIL) in patients with clear cell renal cancer (ccRCC). METHODS: The frequency of PC, PD1 expression and the frequency of intratumoral CD8+ TIL were evaluated in 104 ccRCC patients. RESULTS: The median frequency of PC was 0.003. The expression of PD1+ cells were <5% in 52 patients, 5-25% in 34 patients and 26-50% in 13 patients and >50% in 5 patients. Intratumoral CD8+ TIL were evaluable in all patients: negative in 1 patient, <25% in 63, 26-50% in 29 and >50% in 11 patients. Overall survival (OS) according to the frequency of PC was significantly shorter in patients with higher frequency (≥0.002) than in patients with lower frequency (<0.002) (p<0.001). Median OS was significantly shorter in patients with higher (25%) CD8+ TIL and higher (>25%) PD1+ expression than in patients with lower (<25%) expression (4.6 vs. 97. years, p=0.006 and 2.9 vs. 8.9 years, p=0.006, respectively). CONCLUSIONS: The present study provides the first data on the potential association and combined prognostic significance of frequency of PC, PD1+ cells and CD8+ TIL in patients with clear cell renal cancer.

The toxic effect of cytostatics on primary cilia frequency and multiciliation.

The primary cilium is considered as a key component of morphological cellular stability. However, cancer cells are notorious for lacking primary cilia in most cases, depending upon the tumour type. Previous reports have shown the effect of starvation and cytostatics on ciliogenesis in normal and cancer cells although with limited success, especially when concerning the latter. In this study, we evaluated the presence and frequency of primary cilia in breast fibroblasts and in triple-negative breast cancer cells after treatment with cytostatics finding that, in the case of breast fibroblasts, primary cilia were detected at their highest incidence 72 hours after treatment with 120 nM doxorubicin. Further, multiciliated cells were also detected after treatment with 80 nM doxorubicin. On the other hand, treatment with taxol increased the number of ciliated cells only at low concentrations (1.25 and 3.25 nM) and did not induce multiciliation. Interestingly, triple-negative breast cancer cells did not present primary cilia after treatment with either doxorubicin or taxol. This is the first study reporting the presence of multiple primary cilia in breast fibroblasts induced by doxorubicin. However, the null effect of these cytostatics on primary cilia incidence in the evaluated triple negative breast carcinomas cell lines requires further research.

Comparative Study on the Application of Mesenchymal Stromal Cells Combined with Tricalcium Phosphate Scaffold into Femoral Bone Defects.

This prospective study sought to evaluate the healing quality of implanted ultraporous ß-tricalcium phosphate sown with expanded autologous mesenchymal stromal cells (MSCs) into femoral defects during revision hip arthroplasty. A total of 37 osseous defects in 37 patients were treated and evaluated concerning bone regeneration. Nineteen subjects received ß-tricalcium phosphate graft material serving as a carrier of expanded autologous MSCs (the trial group A), nine subjects received ß-tricalcium phosphate graft material only (the study group B) and nine subjects received cancellous allografts only (the control group C). Clinical and radiographic evaluations were scheduled at 6 weeks, 3, 6, and 12 months post-operatively, and performed at the most recent visit as well. All observed complications were recorded during follow-up to assess the use of an ultraporous ß-tricalcium phosphate synthetic graft material combined with expanded MSCs in bone defect repair. The resulting data from participants with accomplished follow-up were processed and statistically evaluated with a Freeman-Halton modification of the Fischer's exact test, a P < 0.05 value was considered to be significant. Whereas no significant difference was observed between the trial group A with ß-tricalcium phosphate synthetic graft material serving as a carrier of expanded autologous MSCs and control group C with cancellous impaction allografting in terms of the bone defect healing, significant differences were documented between the study group B with ß-tricalcium phosphate graft material only and control group C. Regarding adverse effects, six serious events were recorded during the clinical trial with no causal relationship to the cell product. ß-tricalcium phosphate synthetic graft material serving as a carrier of expanded autologous MSCs appears safe and promotes the healing of bone defects in a jeopardized and/or impaired microenvironment. This clinical trial was registered at the EU Clinical Trials Register before patient recruitment (Registration number: EudraCT number 2012-005599-33; Date of registration: 2013-02-04).

The Transplantation of hBM-MSCs Increases Bone Neo-Formation and Preserves Hearing Function in the Treatment of Temporal Bone Defects - on the Experience of Two Month Follow Up.

Temporal bone reconstruction is a persisting problem following middle ear cholesteatoma surgery. Seeking to advance the clinical transfer of stem cell therapy we attempted the reconstruction of temporal bone using a composite bioartificial graft based on a hydroxyapatite bone scaffold combined with human bone marrow-derived mesenchymal stromal cells (hBM-MSCs). The aim of this study was to evaluate the effect of the combined biomaterial on the healing of postoperative temporal bone defects and the preservation of physiological hearing functions in a guinea pig model. The treatment's effect could be observed at 1 and 2 months after implantation of the biomaterial, as opposed to the control group. The clinical evaluation of our results included animal survival, clinical signs of an inflammatory response, and exploration of the tympanic bulla. Osteogenesis, angiogenesis, and inflammation were evaluated by histopathological analyses, whereas hBM-MSCs survival was evaluated by immunofluorescence assays. Hearing capacity was evaluated by objective audiometric methods, i.e. auditory brainstem responses and otoacoustic emission. Our study shows that hBM-MSCs, in combination with hydroxyapatite scaffolds, improves the repair of bone defects providing a safe and effective alternative in their treatment following middle ear surgery due to cholesteatoma.

Simulations of centriole of polarized centrosome as a monopole antenna in immune and viral synapses.

The immune synapse (IS) is a temporary interface between an antigen-presenting cell and an effector lymphocyte. Viral synapse is a molecularly organized cellular junction that is structurally similar to the IS. Primary cilium is considered as a functional homologue of the IS due to the morphological and functional similarities in architecture between both micotubule structures. It has been hypothesized that endogenous electromagnetic field in the cell is generated by a unique cooperating system between mitochondria and microtubules. We are extending this prior hypothesis of the endogenous electromagnetic field in the cell postulating that polarized centriole in immune and viral synapse could serve as a monopole antenna. This is an addition to our hypothesis that primary cilium could serve as a monopole antenna. We simulated the distribution of electric field of centriole of polarized centrosome as a monopole antenna in immune and viral synapse. Very weak electromagnetic field of polarized centriole of CD8+ T lymphocyte in IS can contribute to the transport of cytolytic granules into the attacked (cancer) cell. Analogically, very weak electromagnetic field of polarized centriole in viral synapse of infected CD4 cells can aid the transport of viruses (human immunodeficiency virus) to non-infected CD4 cells. We hypothesized that healthy organisms need these monopole antennas. If, during the neoplastic transformation, healthy cells lose monopole antennas in form of primary cilia, the IS aims to replace them by monopole antennas of polarized centrioles in IS to restore homeostasis.

New Light on An Old Friend: Targeting PUMA in Radioprotection and Therapy of Cardiovascular and Neurodegenerative Diseases.

This review summarizes recent progress in understanding the role of p53-upregulated mediator of apoptosis (PUMA) in molecular pathways with respect to its potential therapeutic applications. Particular emphasis is given to the PUMA´s role in ionizing radiation-induced signalling as radiotoxicity of normal tissue is mediated mostly via apoptosis. PUMA and its p53-dependent and p53- independent induction are described and potential use as a new target for the development of radioprotective agents is suggested. Further implications, including targeting PUMA to prevent and treat cardiovascular and neurodegenerative diseases, are also discussed together with an overview of other therapeutic applications. Finally, basic chemical structures for the development of novel PUMA modulators such as pifithrine derivatives, kinase inhibitors or modulators of Bcl-2 protein family are described.

Association of the combined parameters including the frequency of primary cilia, CD8+ tumor infiltrating lymphocytes and PD-1 expression with the outcome in intestinal cancer.

PURPOSE: Primary cilium (PC) is considered to be a functional homologue of the immune synapse. Microtubule structures, PC of cancer associated fibroblasts and immune synapses between cytotoxic CD8+ tumor infiltrating lymphocytes (TILs) and cancer cells, are regularly found in varying amounts in the microenvironment of solid tumors. The purpose of this study was to find out the potential association and combined prognostic significance of the frequency of PC, PD-1 and CD8+ TILs in patients with intestinal cancer. METHODS: The frequency of PC, programmed cell death protein-1 receptor (PD-1) expression and the frequency of stromal and intraepithelial CD8+TILs were evaluated in samples of colorectal adenocarcinoma (32 patiens) and small bowel cancer (8 patients). RESULTS: The median frequency of PC was 0.25%. The expression of PD1 was <5% in 34 patients, 5-25% in 5 patients and 26-50% in 1 patient. The frequency of stromal CD8+ TILs was negative in 3 patients, <25% in 26, 26-50% in 10 and >50% in 1 patient, respectively. Intraepithelial CD8+ TILs were not detectable in 14, <25% in 24 and 26-50% in 2 patients, respectively. Statistically, the frequency of PC and PD-1 positivity were significantly associated (p=0.004). An association between the PC frequency and intraepithelial CD8+ TILs was of borderline statistical significance (p=0.059). An index combining the frequency of PC and stromal CD8+ TILs, but not the combination of frequency of PC and intraepithelial CD8+ TILs, was of borderline prognostic significance (p=0.067). CONCLUSIONS: The present study provides the first data on the potential association and combined prognostic significance of frequency of PC, PD-1 and CD8+ TILs in patients with intestinal cancer.

Prognostic significance of the frequency of primary cilia in cells of small bowel and colorectal adenocarcinoma.

PURPOSE: The primary cilium is a solitary, sensory, immotile microtubule-based structure that arises from the centrosome and is projected from the surface of most human cell types. It has been hypothesized that primary cilia could serve as a tumor suppressor organelle. The objective of this pilot study was to investigate the presence and frequency of primary cilia in cells of small bowel and colorectal adenocarcinoma and to evaluate the prognostic significance of their frequency. METHODS: The presence of primary cilia in cells in samples of small bowel (8 patients) and colorectal adenocarcinoma (32 patients) was evaluated. The primary cilia of cells were immunofluorescently labeled using primary monoclonal anti-acetylated agr;-tubulin antibody and cell nuclei were labeled using DAPI. RESULTS: Primary cilia were identified in all examined specimens. The median frequency of primary cilia was 0.49% in cells of small bowel cancer and 0.22% in cells in colorectal cancer. Overall survival according to frequency of primary cilia in all intestinal adenocarcinomas was significantly longer in patients with higher frequency (≥ 0.187) than in patients with lower frequency of primary cilia (< 0.187) in univariate analysis (p=0.007) and also in the Cox proportional hazard model (p=0.032). Overall survival according to frequency of primary cilia in colorectal adenocarcinoma was significantly longer in patients with higher frequency (≥ 0.187) than in patients with lower frequency of primary cilia (< 0.187) (p=0.028). CONCLUSIONS: The present pilot study provides the first evidence of the prognostic significance of the frequency of primary cilia in small bowel and colorectal adenocarcinoma. Because of significantly higher median frequency of primary cilia in the rare small bowel adenocarcinoma than in the frequent colorectal adenocarcinoma (p<0.001), the results of this study support a potential role for primary cilia as a biomarker in these types of cancer.

Effective Method of Purification of Betulin from Birch Bark: The Importance of Its Purity for Scientific and Medicinal Use.

A new and relatively simple method for purification of betulin from birch bark extract was developed in this study. Its five purification steps are based on the differential solubility of extract components in various solvents and their crystallization and/or precipitation, on their affinity for Ca(OH)2 in ethanol, and on the affinity of some impurities for silica gel in chloroform. In addition, all used solvents can be simply recycled. Betulin of more than 99% purity can be prepared by this method with minimal costs. Various observations including crystallization of betulin, changes in crystals during heating, and attempt of localization of betulin in outer birch bark are also described in this work. The original extract, fraction without betulinic acid and lupeol, amorphous fraction of pure betulin, final crystalline fraction of pure betulin and commercial betulin as a standard were employed to determine the antiproliferative/cytotoxic effect. We used WST-1 tetrazolium-based assays with triple negative breast cancer cell line BT-549. The decrease in cell survival showed clear relationship with the purity of the samples, being most pronounced using our final product of pure crystalline betulin. WST-1 proliferation/cytotoxicity test using triple negative breast cancer cell line BT-549 clearly showed the importance of purity of betulin for biological experiments and, apparently, for its medicinal use.

Ionizing radiation increases primary cilia incidence and induces multiciliation in C2C12 myoblasts.

Primary cilia act as physical-chemical sensors and their functions include the perception of the extracellular milieu, regulation of organogenesis, and cell polarity. In general, these cells are monociliated and the single cilium possesses diverse receptors and channels which are involved in morphogenesis and growth signaling, and are, therefore, important for cell proliferation and differentiation. In this study, we used an in vitro model of C2C12 myoblasts to evaluate the effect of DNA damage induced by gamma ionizing radiation on primary cilia incidence. A significantly higher number of ciliated cells were observed after 1 day post-irradiation with 2-20 Gy when compared with non-irradiated cells. After 3 days post-irradiation, the cilia incidence in cells had decreased slightly when treated with 2, 6, and 10 Gy, although an increase in incidence rate was observed in cells treated with 20 Gy. Multi-ciliated cells were also detected in myoblasts irradiated with 10 and 20 Gy but not in non-irradiated cells or after low irradiation (2-6 Gy). Irradiation also caused a dose-dependent decrease in cell viability and proliferation and corresponding cell cycle arrest. Furthermore, an activation of caspases 3/7, 8, and 9 was observed after higher radiation (10 and 20 Gy) with increased apoptosis. Together, our results show that irradiation by gamma rays promotes myoblast ciliogenesis, with pronounced effects observed after 3 days post-irradiation. We conclude that irradiation doses of 10 and 20 Gy are sufficient to induce cell death and are responsible for the formation of multiple cilia originating from multiple basal bodies.