Exploring the combined anti-cancer effects of sodium butyrate and celastrol in glioblastoma cell lines: a novel therapeutic approach.

Glioblastoma, a highly aggressive and lethal brain cancer, lacks effective treatment options and has a poor prognosis. In our study, we explored the potential anti-cancer effects of sodium butyrate (SB) and celastrol (CEL) in two glioblastoma cell lines. SB, a histone deacetylase inhibitor, and CEL, derived from the tripterygium wilfordii plant, act as mTOR and proteasome inhibitors. Both can cross the blood-brain barrier, and they exhibit chemo- and radiosensitive properties in various cancer models. GB cell lines LN-405 and T98G were treated with SB and CEL. Cell viability was assessed by MTT assay and IC50 values were obtained. Gene expression of DNA repair, apoptosis, and autophagy-related genes was analyzed by RT-PCR. Cell cycle distribution was determined using flow cytometry. Viability assays using MTT assay revealed IC50 values of 26 mM and 22.7 mM for SB and 6.77 µM, and 9.11 µM for CEL in LN-405 and T98G cells, respectively. Furthermore, we examined the expression levels of DNA repair genes (MGMT, MLH-1, MSH-2, MSH-6), apoptosis genes (caspase-3, caspase-8, caspase-9), and an autophagy gene (ATG-6) using real-time polymerase chain reaction. Additionally, flow cytometry analysis revealed alterations in cell cycle distribution following treatment with SB, CEL and their combination. These findings indicate that SB and CEL may act through multiple mechanisms, including DNA repair inhibition, apoptosis induction, and autophagy modulation, to exert their anti-cancer effects in glioblastoma cells. This is the first study providing novel insights into the potential therapeutic effects of SB and CEL in glioblastoma.

Vitamin D may assist the UPR against sodium fluoride-induced damage by reducing RIPK1, ATG5, BECN1, oxidative stress and increasing caspase-3 in the osteoblast MC3T3-E1 cell line.

BACKGROUND: Out of all measure systemic exposure to fluorides can cause defect of skeletal and dental fluorosis. Endoplasmic reticulum (ER) stress is caused by fluorine-induced oxidative stress and importance of vitamin D in its prevention is not known enough in bone cells. This study was carried out to investigate fluorine-induced oxidative stress, ER stress, and death pathways and the effect of vitamin D on them. METHODS: MC3T3-E1 mouse osteoblast cell line was used as the material of the study. The NaF and vitamin D concentrations were determined by the MTT assay. NaF treatments and vitamin D supplementation (pre-add, co-add, and post-add) was administered in the cell line at 24th and 48th hours. The expression of the genes in oxidative stress, ER stress, and death pathways was determined using RT-qPCR and Western blotting techniques. RESULTS: Vitamin D significantly reduced mRNA expression levels of SOD2, CYGB, ATF6, PERK, IRE1, ATG5 and BECN1 whereas caused an increase in levels GPX1, SOD1, NOS2 and Caspase-3 in MC3T3-E1 mouse osteoblast cell line of NaF-induced. In addition, GPX1, SOD1, ATF6, PERK, IRE1, BECN1, Caspase-3 and RIPK1 protein levels were examined by Western blot analysis, and it was determined that vitamin D decreased IRE1 and PERK protein levels, but increased GPX1, SOD1, ATF6 and Caspase-3 protein levels. CONCLUSION: The findings of the study suggest that vitamin D has protective potential against NaF-induced cytotoxicity reasonably through the attenuation of oxidative stress, ER stress, ATG5, IRE1 and by increasesing caspase-3 in vitro conditions.

The antagonistic effects of temozolomide and trichostatin a combination on MGMT and DNA mismatch repair pathways in Glioblastoma.

Glioblastoma is the most aggressive and fatal form of brain cancer. Despite new advancements in treatment, the desired outcomes have not been achieved. Temozolomide (TMZ) is the first-choice treatment for the last two decades and has improved survival rates. Emerging studies have shown that targeting epigenetics in glioblastoma can be beneficial when combined with clinically used treatments. Trichostatin A (TSA), a histone deacetylase inhibitor, has anti-cancer properties in various cancers. No data concerning the TMZ and TSA relationship was shown previously in glioblastoma therefore, we aimed to determine the likely therapeutic effect of the TMZ and TSA combination in glioblastoma. The T98G and U-373 MG, glioblastoma cell lines, were used in this study. TMZ and TSA cytotoxicity and combination index were performed by MTT assay. The expression of DNA repair genes (MGMT, MLH-1, PMS2, MSH2 and MSH6) was detected using RT-PCR. One-way analysis of variance (ANOVA) was used for statistical analysis. Combination index calculations revealed antagonistic effects of TMZ and TSA in terms of cytotoxicity. Antagonistic effects were more apparent in the T98G cell line, which is expressing MGMT relatively higher. MGMT and DNA Mismatch Repair (MMR) genes were upregulated in the T98G cell line, whereas downregulated in the U373-MG cell lines under TMZ and TSA combination treatment. It is concluded that MGMT might be playing a more active part than MMR genes in TMZ resistance to TMZ and TSA antagonism. This is the first study elucidating the TMZ and TSA relationship in cancer cell lines.

The Effects of Vitamin D Application on NaF-Induced Cytotoxicity in Osteoblast Cells (hFOB 1.19).

This study was planned to evaluate the effect of vitamin D administration on cytotoxicity due to fluoride exposure in vitro. NaF (IC50) and vitamin D (proliferative) were applied to human osteoblast (hFOB 1.19) cells. The major genes of apoptotic, autophagic, and necrotic pathways were determined by RT-PCR. 2-∆∆Ct formulation was used for expression analysis. In the NaF group, caspase 3, Bax, Bad, Bak, Bclx, Atg3, Atg5, Atg6, pG2, LC3-I, LC3-II, RIP1, and RIP3 genes were increased (2.6-15 times). It was observed that the expressions of these genes approached the control when vitamin D was given together with NaF. The Bcl2 gene increased significantly (sixfold) with the effect of NaF, and was down-regulated to some extent with additional vitamin D administration, but still more than in the control. As a result, it was determined that apoptotic, necrotic, and autophagic pathways were activated as the molecular basis of the damage in the bone tissue, which was most affected by fluorine, and these genes were down-regulated and approached the control group with the addition of vitamin D. It was concluded that this is an important data to explain the molecular basis of the protective and therapeutic effect of vitamin D against fluorine toxicity.

The Effects of Different Doses of ROCK Inhibitor, Antifreeze Protein III, and Boron Added to Semen Extender on Semen Freezeability of Ankara Bucks.

In the presented study, the effects of ROCK inhibitor Y-27632, antifreeze protein III, and boron at two different doses were investigated on the spermatological parameters of Ankara buck semen after freeze−thawing. Ejaculates were collected from bucks using an electroejaculator during the breeding season. The ejaculates that showed appropriate characteristics were pooled and used in the dilution and freezing of semen. The extender groups were formed by adding two different doses of three different additives (ROCK inhibitor Y-27632, 5 and 20 µM; antifreeze protein III, 1 and 4 µg/mL; boron, 0.25 and 1 mM) to the control extender. The semen was diluted with the different extenders at 35−37 °C and loaded into straws. Sperm samples frozen in liquid nitrogen vapors, following equilibration, were stored in liquid nitrogen. It was observed that extender supplementation improved post-thaw motility of Ankara buck semen after freeze−thawing. Differences were significant (p < 0.01) for 5 and 10 µM doses of ROCK inhibitor (71.82% and 74.04 % motility), as well as for 0.25 and 1 mM doses of boron (76.36% and 72.08% motility), compared to the control group (66.15% motility). With respect to the evaluation of acrosomal integrity and mitochondrial activity after freeze−thawing, although supplementation provided protection at all doses, the efficacy was not statistically significant (p > 0.05). It was observed that DNA damage was improved by antifreeze protein III at 1 µg/mL (1.23% ± 0.23%) and by boron at all doses (0.25 mM: 1.83% and 1 mM: 1.18%) compared to the control group (3.37%) (p < 0.01), following the thawing process. In the present study, it was determined that some additives added to the extender provided significant improvements in buck spermatozoa motility and DNA damage after thawing.

Effect of Endoscopic Ureteral Stone Treatment on Kidney Function.

INTRODUCTION: Ureteral stones may have an influence on kidney functions due to postrenal obstruction or urinary infections. Urgent decompression or stone removal is necessary and recommended to prevent further complications in case of severe conditions such as anuria and urosepsis. Although it is believed that ureteral stone removal would result in renal function improvement, there are still unclear points on whether ureteroscopy (URS) can provide benefit as expected and has some adverse effects. In this study, we aimed to evaluate the alteration of kidney functions of patients who undergo rigid or flexible URS for ureteral stones and find if there are any influencing factors on kidney function alteration. MATERIALS AND METHOD: We analyzed 126 patients who underwent retrograde intrarenal surgery (RIRS) for renal stones between May 2018 and February 2020 prospectively. The estimated glomerular filtration rate (eGFR) was calculated on the day before the surgery, by modification of diet in renal disease (MDRD) formula. The calculation was repeated and saved three times during follow-up for the same patient; on the day after the operation, on the postoperative 30th day, and the postoperative 90th day. Then, we evaluated the renal function by comparing eGFR and assessed the predicting factors affecting the kidney function. RESULTS: Preoperative mean eGFR was 82.28 ± 25.20 mL/min/1.73 m2 for the study group. Mean eGFR was calculated 90.92 ± 22.97 mL/min/1.73 m2 on the first postoperative day, and 94.54 ± 21.95 mL/min/1.73 m2 on the third-month follow-up. The mean change in eGFR was 8.63 ± 16.68 mL/min/1.73 m2 in the early period and 12.26 ± 21.09 mL/min/1.73 m2 in the long-term follow-up period. Fifty-one patients improved on chronic kidney disease (CKD) stage, and 13 deteriorated in three months follow-up. CONCLUSION: Removing the stone and relieving the obstruction by ureteroscopic treatment have an alteration on eGFR. Although eGFR improves in the short-term follow-up, amelioration is evident in long-term follow-up, especially in female patients. The other predictive factors for eGFR improvement after URS are the presence of ureteral obstruction and high preoperative serum creatinine levels.

Evaluation of the influence of subinguinal varicocelectomy procedure on seminal parameters, reproductive hormones and testosterone/estradiol ratio.

OBJECTIVE: Varicocele is the most commonly surgically curable cause of male infertility. However, the mechanisms related to the effect of reducing fertility potential have not been clearly identified. The aim of this study was to investigate the effects of varicocelectomy on semen parameters, reproductive hormones and testosterone / estradiol ratio. Matherial and methods: Fifty seven patients outcomes were evaluated before and 6 months after subinguinal microsurgical varicocelectomy. Semen parameters, reproductice hormones and testosteron/estradiol ratio results of patients were compared retrospectively. RESULTS: The mean age was 26.8 years. Fifty four (94.7%) patients had grade 3 and 3 (5.3%) patients had grade 2 varicocele. There was a significant increase in semen parameters except semen volume. There was a statistically significant increase in serum testosterone levels, but not on testosterone/ estradiol ratio. CONCLUSIONS: According to our results, microsurgical subinguinal varicocelectomy can be recommended for both improving semen parameters and hormonal recovery.

Factors Affecting Retrograde Intrarenal Surgery Success: 6 Years Experience of a Clinic in Central Anatolia.

Background: Urinary system stone disease is an important health problem. It has been reported to have a prevalence of 14.8% in Turkey. The aim of the renal stone removal surgery is to clear the stones with minimal complications. Retrograde intrarenal surgery (RIRS) is a safe method due to the fewer and minor complications. As a clinic in central Anatolia, we aimed at researching the factors affecting RIRS success in our area. Methods: After local ethics committee's approval, the data of the patients who had undergone RIRS between 2014 and 2019 were reviewed. Patients who were <18 years old, had kidney anomalies, and had both ureter and kidney stones were excluded from the study. The patients who were defined as successful were named as Group 1 and the others were named as Group 2. The demographic, intraoperative, and postoperative data of the two groups were compared. Results: There were a total of 416 patients in our study. Group 1 consisted of 332 patients, whereas Group 2 had 84 patients. Opacity was significantly different between the groups (P = .004). Stone size, stone volume, and operation time were significantly higher in Group 2. After logistic regression analysis, we found that stone size, opacity, and operation time affected the success of RIRS significantly (P < .05). There was a reverse relationship with stone size, operation time, and opacity. Conclusions: We believe that in patients who have large lower calix stones and who want effective treatment, percutaneous nephrolithotomy should still be an option for treatment.

Mono- or di-substituted imidazole derivatives for inhibition of acetylcholine and butyrylcholine esterases.

Mono- or di-substituted imidazole derivatives were synthesized using a one-pot, two-step strategy. All imidazole derivatives were tested for AChE and BChE inhibition and showed nanomolar activity similar to that of the test compound donepezil and higher than that of tacrine. Structure activity relationship studies, docking studies to on X-ray crystal structure of AChE with PDB code 1B41, and adsorption, distribution, metabolism, and excretion (ADME) predictions were performed. The synthesized core skeleton was bound to important regions of the active site of AChE such as the peripheral anionic site (PAS), oxyanion hole (OH), and anionic subsite (AS). Selectivity of the reported test compounds was calculated and enzyme kinetic studies revealed that they behave as competitive inhibitors, while two of the test compounds showed noncompetitive inhibitory behavior. ADME predictions revealed that the synthesized molecules might pass through the blood brain barrier and intestinal epithelial barrier and circulate freely in the blood stream without binding to human serum albumin. While the toxicity of one compound on the WS1 (skin fibroblast) cell line was 1790 µM, its toxicity on the SH-SY5Y (neuroblastoma) cell line was 950 µM.

In Vitro evaluation of thymoquinone on apoptosis and oxidative DNA damage in high glucose condition.

The study was planned to investigate the effects of thymoquinone (TQ), which is a compound in N. sativa, on caspase dependent apoptosis and oxidative DNA damage in high glucose treated PC12 cells. PC12 cells were treated with high glucose (G1-150 mM, G2-250 mM, G3-350 mM), TQ (20 µM), and their combinations. Oxidative DNA damage (8-OHdG (8-Oxo-2'-deoxyguanosine)), and apoptosis (caspase 3, caspase 8, caspase 9 enzymes and M30 protein) parameters were analyzed with ELISA. The 8-OHdG levels decreased in all combination groups compared to the control (p≤0.001). There was no statistically significant difference between caspase 3 and 9. Caspase 8 in TQ, G3, TQG1, TQG2 groups were higher than the control (p≤0.002). Low M30 levels were observed in TQG1 group (p≤0.002). In conclusion, it was observed that in PC12 cell line treated with the high glucose concentrations, TQ administration had a statistically significant effect on oxidative DNA damage and some apoptotic parameters (caspase 8 and M30 protein).

Effect of metformin/irinotecan-loaded poly-lactic-co-glycolic acid nanoparticles on glioblastoma: in vitro and in vivo studies.

AIM: The present study was designed to evaluate the effects of irinotecan hydrochloride (IRI)- or metformin hydrochloride (MET)-loaded poly-lactic-co-glycolic acid (PLGA) nanoparticles (NPs) for the treatment of glioblastoma multiforme using in vitro neuron and U-87 MG glioblastoma cell cultures and in vivo animal model. METHODS: The cytotoxic and neurotoxic effects of pure drugs, blank NPs and MET- and IRI-loaded PLGA NPs were investigated in vitro (using methylthiazolyldiphenyl-tetrazolium bromide assay) and in vivo (using Cavalieri's principle for estimation of cancer volume). RESULTS: 1 and 2 mM doses of MET and MET-loaded PLGA NPs, respectively, significantly reduced the volume of extracted cancer. CONCLUSION: Consequently, MET- and IRI-loaded PLGA NPs may be a promising approach for the treatment of glioblastoma multiforme.

Synthesis of novel imidazopyridines and their biological evaluation as potent anticancer agents: A promising candidate for glioblastoma.

Novel imidazopyridine derivatives were synthesized according to a very simple protocol and then subjected to cytotoxicity testing against LN-405 cells. Two of the compounds exhibited antiproliferative effects on LN-405 cells at 10 and 75 µM and were selected as lead compounds for further study. Safety experiment for lead compounds on WS1 was carried out and IC50 values were calculated as 480 and 844 µM. LN-405 cell line were incubated with the lead compounds and then tested for DNA damage by comet assay and effects on cell cycle using flow cytometry. The results of these two tests showed that both lead compounds affected the G0/G1 phase and did not allow the cells to reach the synthesis phase. The log BB (blood-brain barrier) and Caco-2 permeability of the synthesized molecules were calculated and it was shown that imidazopyridine derivatives taken orally are likely to pass through gastrointestinal membrane and the blood-brain barrier.

Genetic Polymorphisms in PRM1, PRM2, and YBX2 Genes are Associated with Male Factor Infertility.

AIMS: The etiology of infertility is still unknown in almost half of all male infertility patients. In sperm, DNA condensation differs from somatic and female gamete cells, with the protamine (PRM) gene and its transcription factor, Y-box binding protein 2 (YBX2), playing key roles in making the structure more compact. Protamine polymorphisms have been studied in different populations, but various results have been acquired. MATERIALS AND METHODS: In our study, we examined, for the first time in a Turkish population, the association between protamine gene alleles (PRM1 c.-190C>A, PRM1 c.197G>T, and PRM2 c.248C>T), and YBX2 (c.187T>C and c.1095 + 16A>G) and male infertility. This was accomplished using polymerase chain reaction-restriction fragment length polymorphism analyses of 100 infertile and 100 fertile Turkish men. Sperm DNA fragmentation analysis was performed using the Comet technique. RESULTS: We found that the AA and CA genotypes of the PRM1 c.-190C>A polymorphism had a significant association with infertility (p < 0.001) and the AA genotype was also highly significantly associated with high sperm DNA damage (p < 0.001). CONCLUSION: This study demonstrates that the PRM1 c.-190C>A polymorphism is associated with sperm DNA fragmentation, which may impact male infertility in the Turkish population. Further research with larger groups and in various other study populations will be required to clarify the impact of protamine and YBX2 gene polymorphisms on male infertility.

Determining the relationship between atherosclerosis and periodontopathogenic microorganisms in chronic periodontitis patients.

OBJECTIVES: The aim of this study is to determine the relationship between atherosclerosis and periodontopathogenic microorganisms in chronic periodontitis patients following periodontal treatment. MATERIALS AND METHODS: A total of 40 patients were included in the study. 20 of these patients diagnosed with atherosclerosis and chronic periodontitis formed the test group. The remaining 20 patients were systemically healthy patients diagnosed with chronic periodontitis and formed the control group. All patients had nonsurgical periodontal treatment. The periodontopathogenic microorganism levels were determined at baseline and at 6 months in microbial dental plaque samples and WBC, LDL, HDL, PLT, fibrinogen, creatinine and hs-CRP levels were determined by blood samples. RESULTS: Statistically significant reduction has been achieved in clinical periodontal parameters following non-surgical periodontal treatment in test and control groups. Following periodontal treatment, WBC, LDL, PLT, fibrinogen, creatinine and hs-CRP levels significantly decreased and HDL levels significantly increased in both test and control groups. Similarly, the periodontopathogenic microorganism levels significantly decreased following periodontal treatment in the test and control groups. A statistically significant positive correlation has been determined between the periodontopathogenic microorganism levels and WBC, LDL, PLT, fibrinogen, creatinine, and hs-CRP levels in the test group. CONCLUSIONS: The association between hs-CRP, WBC, LDL, PLT, fibrinogen, creatinine, and the amount of periodontopathogenic microorganisms indicates the possibility that periodontal treatment could decrease the risk atherosclerosis. More studies must be conducted in order for these results to be supported.

Caveolin-1 polymorphisms in patients with severe obstructive sleep apnea.

OBJECTIVE: To investigate the associations of G14713A and T29107A polymorphic variants of Caveolin-1 with severe obstructive sleep apnea (OSA). MATERIALS AND METHODS: This study was performed on 86 severe OSA patients and 86 controls. Genotyping was performed to investigate the association of G14713A and T29107A polymorphisms of Caveolin-1 with severe OSA. RESULTS: The distribution of genotypes of T29107A was significantly different between controls and OSA patients with a higher proportion of TT carriers in the OSA group. CONCLUSION: T29107A-specific genotype of Caveolin-1 may be linked with severe OSA pathogenesis.

Impact of follicle-stimulating hormone receptor variants in female infertility.

PURPOSE: Follicle-stimulating hormone (FSH) and its receptor play a major role in the development of follicles and regulation of steroidogenesis in the ovary and spermatogenesis in the testis. We aim to analyze the role of FSHR gene variants (single nucleotide polymorphisms (SNPs) in exon 10 (codon 307 and 680) and in the core promoter region (at position -29) and Ala189Val inactivating mutation) in Turkish infertile women. There were studies analyzing the effects of the SNPs in exon 10 (codon 307 and 680) and in the core promoter region (at position -29) of the FSHR gene on spermatogenesis, but to our knowledge, there were no studies analyzing the effects of these three SNP combinations on female fertility. METHODS: In this study, the allelic, genotype, and haplotype frequency distributions of these three SNPs in the FSHR gene were analyzed in 102 infertile women and 99 unrelated healthy control individuals. The distribution of the polymorphisms was conformed by Hardy-Weinberg equilibrium test. RESULTS: There were no statistical differences (P > 0.05) in the allele, genotype, and haplotype frequencies of the polymorphisms and FSH, luteinizing hormone (LH), estradiol (E2), and prolactin (PRL) levels between the infertile patients and the controls. However, a significant relation was found between 307 SNP GA genotype and FSH level ≥12. We did not find any homozygous or heterozygote mutations in infertile patients and healthy fertile controls. CONCLUSION: The present study was the first study analyzing gma mutation and the polymorphism of the FSHR core promoter at position -29 alone and in combination with the two common SNPs in exon 10 in Turkish infertile women population. These findings indicate the significance of Ala307Thr GA genotype may be a predictive marker for poor ovarian reserve and infertility.

Chemotherapeutic resistance in anaplastic astrocytoma cell lines treated with a temozolomide-lomeguatrib combination.

The treatment of anaplastic astrocytoma (AA) is controversial. New chemotherapeutic approaches are needed for AA treatment. Temozolomide (TMZ) is one of the chemotherapeutic drugs for the treatment of AA. The cytotoxic effects of TMZ can be removed by the MGMT (O(6)-methylguanine-DNA methyltransferase) enzyme. Then, chemotherapeutic resistance to TMZ occurs. MGMT inhibition by MGMT inactivators (such as lomeguatrib) is an important anticancer therapeutic approach to circumvent TMZ resistance. We aim to investigate the effect of TMZ-lomeguatrib combination on MGMT expression and TMZ sensitivity of SW1783 and GOS-3 AA cell lines. The sensitivity of SW1783 and GOS-3 cell lines to TMZ and to the combination of TMZ and lomeguatrib was determined by a cytotoxicity assay. MGMT methylation was detected by MS-PCR. MGMT and p53 expression were investigated by real-time PCR after drug treatment, and the proportion of apoptotic cells was analyzed by flow cytometry. When the combination of TMZ-lomeguatrib (50 µM) was used in AA cell lines, IC50 values were reduced compared to only using TMZ. MGMT expression was decreased, p53 expression was increased, and the proportion of apoptotic cells was induced in both cell lines. The lomeguatrib-TMZ combination did not have any effect on the cell cycle and caused apoptosis by increasing p53 expression and decreasing MGMT expression. Our study is a pilot study investigating a new therapeutic approach for AA treatment, but further research is needed.

HHV-6 is ubiquitously found using Western blot in tonsils and adenoid tissues of healthy people.

Few studies have examined the prevalence and cellular proclivity of latent human herpesvirus 6 (HHV-6) in healthy populations. Difficulties in detection of HHV-6 genome in different tissues using polymerase chain reaction (PCR) and immunohistochemistry (IHC) techniques have been reported by various researchers. We examined tonsils and adenoid tissues of 54 patients who had undergone tonsillectomy or adenoidectomy without any evidence of acute infection for the presence of latent HHV-6 infection. While we were investigating the prevalence of HHV-6, we tested the efficiency of PCR, IHC and Western Blot (WB) for detection of HHV-6 in tonsil tissues. We found that 100% of tonsil tissues were positive for HHV-6 with WB, 40% of tonsils were positive with PCR and no tonsil was positive with IHC. This result correlates well with most studies claiming HHV-6 is a ubiquitous organism in various populations and tissues. Western blot may be a good choice for detecting HHV-6 in tissues. Expression of the HHV-6 gp60/110 envelope protein disclosed by WB may indicate that HHV-6 does not have true latency. To our knowledge, this is the first report to use WB to test for HHV-6 in tissues.

Raffinose and hypotaurine improve the post-thawed Merino ram sperm parameters.

The aim of this study was to determine the effects of raffinose and hypotaurine on sperm parameters after the freeze-thawing of Merino ram sperm. Totally 40 ejaculates of five Merino ram were used in the study. Semen samples, which were diluted with a Tris-based extender containing 10mM raffinose, 5mM hypotaurine, 5mM raffinose +2.5mM hypotaurine (H+R) and no antioxidant (control), were cooled to 5 °C and frozen in 0.25 ml French straws and stored in liquid nitrogen. Frozen straws were then thawed individually at 37 °C for 25s in a water bath for evaluation. The addition of raffinose led to higher percentages of subjective and CASA motilities (47.5 ± 12.2%, 46.3 ± 13.6%) compared to controls (38.8 ± 13.8%, 30.5 ± 11.7%, P<0.05). For the CASA progressive motility, 5mM raffinose (20.12 ± 8.82%) had increasing effect in comparison to control (10 ± 7.94%, P<0.05) following the freeze-thawing process. Raffinose and hypotaurine led to higher viability (40.8 ± 4.68%, 40.8 ± 4.7%), high sperm mitochondrial activity (29.5 ± 5.4%, 27.3 ± 4.9%) and acrosome integrity (50.8 ± 8.1, 50.7 ± 4.4) percentages, compared to control groups (31.5 ± 3.5%, 9.5 ± 8.2%, 42.8 ± 7.3%, P<0.05). H+R group only led to high sperm mitochondrial activity when compared to control group. In the comet test, raffinose and hypotaurine resulted in lower sperm with damaged DNA (6.2% and 3.9%) than that of control (9.1%), reducing the DNA damage. For TUNEL assay, The TUNEL-positive cell was distinguished by distinct nuclear staining. Raffinose and H+R groups resulted in lower sperm with TUNEL-positive cell (1.5 ± 1.2% and 2.1 ± 0.9%) than that of control (4.9 ± 2.5%) (P<0.05). In conclusion, findings of this study showed that raffinose and hypotaurine supplementation in semen extenders provided a better protection of sperm parameters against cryopreservation injury, in comparison to the control groups.

Effect of lomeguatrib-temozolomide combination on MGMT promoter methylation and expression in primary glioblastoma tumor cells.

Temozolomide (TMZ) is commonly used in the treatment of glioblastoma (GBM). The MGMT repair enzyme (O (6)-methylguanine-DNA methyltransferase) is an important factor causing chemotherapeutic resistance. MGMT prevents the formation of toxic effects of alkyl adducts by removing them from the DNA. Therefore, MGMT inhibition is an interesting therapeutic approach to circumvent TMZ resistance. The aim of the study was to investigate the effect of the combination of lomeguatrib (an MGMT inactivator) with TMZ, on MGMT expression and methylation. Primary cell cultures were obtained from GBM tumor tissues. The sensitivity of primary GBM cell cultures and GBM cell lines to TMZ, and to the combination of TMZ and lomeguatrib, was determined by a cytotoxicity assay (MTT). MGMT and p53 expression, and MGMT methylation were investigated after drug application. In addition, the proportion of apoptotic cells and DNA fragmentation was analyzed. The combination of TMZ and lomeguatrib in primary GBM cell cultures and glioma cell lines decreased MGMT expression, increased p53 expression, and did not change MGMT methylation. Moreover, apoptosis was induced and DNA fragmentation was increased in cells. In addition, we also showed that lomeguatrib-TMZ combination did not have any effect on the cell cycle. Finally, we determined that the sensitivity of each primary GBM cells and glioma cell lines to the lomeguatrib-TMZ combination was different and significantly associated with the structure of MGMT methylation. Our study suggests that lomeguatrib can be used with TMZ for GBM treatment, although further clinical studies will be needed so as to determine the feasibility of this therapeutic approach.