Irradiated riboflavin over nonradiated one: Potent antimigratory, antiproliferative and cytotoxic effects on glioblastoma cells.

Riboflavin is a water-soluble yellowish vitamin and is controversial regarding its effect on tumour cells. Riboflavin is a powerful photosensitizer that upon exposure to radiation, undergoes an intersystem conversion with molecular oxygen, leading to the production of ROS. In the current study, we sought to ascertain the impact of irradiated riboflavin on C6 glioblastoma cells regarding proliferation, cell death, oxidative stress and migration. First, we compared the proliferative behaviour of cells following nonradiated and radiated riboflavin. Next, we performed apoptotic assays including Annexin V and caspase 3, 7 and 9 assays. Then we checked on oxidative stress and status by flow cytometry and ELISA kits. Finally, we examined inflammatory change and levels of MMP2 and SIRT1 proteins. We caught a clear antiproliferative and cytotoxic effect of irradiated riboflavin compared to nonradiated one. Therefore, we proceeded with our experiments using radiated riboflavin. In all apoptotic assays, we observed a dose-dependent increase. Additionally, the levels of oxidants were found to increase, while antioxidant levels decreased following riboflavin treatment. In the inflammation analysis, we observed elevated levels of both pro-inflammatory and anti-inflammatory cytokines. Additionally, after treatment, we observed reduced levels of MMP2 and SIRT. In conclusion, radiated riboflavin clearly demonstrates superior antiproliferative and apoptotic effects on C6 cells at lower doses compared to nonradiated riboflavin.

Hydrolyzed Collagen Powder Dressing Improves Wound Inflammation, Perfusion, and Breaking Strength of Repaired Tissue.

Objective: Hydrolyzed collagen-based matrices are widely used as wound care dressings. Information on the mechanism of action of such dressings is scanty. The objective of this study was to test the effect of a specific hydrolyzed collagen powder (HCP), which is extensively used for wound care management in the United States. Approach: The effects of HCP on resolution of wound inflammation, perfusion, closure, and breaking strength of the repaired skin were studied in an experimental murine model. Results: In early (day 7) inflammatory phase of wound macrophages, HCP treatment boosted phagocytosis and efferocytosis of wound-site macrophages. In these cells, inducible reactive oxygen species were also higher on day (d) 7. HCP treatment potentiated the expression of anti-inflammatory interleukin (IL)-10 cytokine and proangiogenic vascular endothelial growth factor (VEGF) production. Excisional wounds dressed with HCP showed complete closure on day 21, while the control wounds remained open. HCP treatment also demonstrated improved quality of wound healing as marked by the improved breaking strength of the closed wound tissue/repaired skin. Innovation: These data represent first evidence on the mechanism of action of clinically used HCP. Conclusion: HCP dressing favorably influenced both wound inflammation and vascularization. Improved breaking strength of HCP-treated repaired skin lays the rationale for future studies testing the hypothesis that HCP-treated closed wounds would show fewer recurrences.

Human fetal dermal fibroblast-myeloid cell diversity is characterized by dominance of pro-healing Annexin1-FPR1 signaling.

Fetal skin achieves scarless wound repair. Dermal fibroblasts play a central role in extracellular matrix deposition and scarring outcomes. Both fetal and gingival wound repair share minimal scarring outcomes. We tested the hypothesis that compared to adult skin fibroblasts, human fetal skin fibroblast diversity is unique and partly overlaps with gingival skin fibroblasts. Human fetal skin (FS, n = 3), gingiva (HGG, n = 13), and mature skin (MS, n = 13) were compared at single-cell resolution. Dermal fibroblasts, the most abundant cluster, were examined to establish a connectome with other skin cells. Annexin1-FPR1 signaling pathway was dominant in both FS as well as HGG fibroblasts and related myeloid cells while scanty in MS fibroblasts. Myeloid-specific FPR1-ORF delivered in murine wound edge using tissue nanotransfection (TNT) technology significantly enhanced the quality of healing. Pseudotime analyses identified the co-existence of an HGG fibroblast subset with FPR1high myeloid cells of fetal origin indicating common underlying biological processes.

SPC212 human mesothelioma cells underwent apoptosis, oxidative stress, and morphological deformation following Astaxanthin treatment.

Astaxanthin (ASX) is one of the keto-carotenoids, which is biologically more active than other counterparts. Besides its variety of beneficial effects, it was reported to exert anticancer effects. Despite its utilization against different cancer types, the effect of ASX on mesothelioma has yet to be well-studied. In this study, our goal is to ascertain how ASX will affect SPC212 human mesothelioma cells. First, the effective doses of ASX against SPC212 cells were investigated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test. Thereafter, with flow cytometry analysis, Annexin-V and caspase 3/7 assay were implemented for the evaluation of apoptotic cell death and an oxidative stress test was carried out to determine how the free radicals changed. Ultimately, the cells' morphology was examined under a light microscope. The effective doses of ASX were found as 50, 100, and 200 µM. In the Annexin V assay, the total apoptosis increased to around 12%, 30%, and 45% with increasing doses of ASX. In the caspase 3/7 assay, the total apoptosis was around 25% and 38% at 100 and 200 µM. In oxidative stress analysis, reactive oxygen species-positive cells rose from 4.54 at the lowest dose to 86.95 at the highest dose. In morphological analysis, cellular shrinkage, decrease in cell density, swelling and vacuolations in some cells, membrane blebbing, and apoptotic bodies are observed in ASX-treated cells. To conclude, the current study provided insights into the efficacy and effects of ASX against SPC212 mesothelioma cells regarding morphology, proliferation, and cell death for future studies.

The Prolonged Terminal Phase of Human Life Induces Survival Response in the Skin Transcriptome.

Human death marks the end of organismal life under conditions such that the components of the human body continue to be alive. Such postmortem cellular survival depends on the nature (Hardy scale of slow-fast death) of human death. Slow and expected death typically results from terminal illnesses and includes a prolonged terminal phase of life. As such organismal death process unfolds, do cells of the human body adapt for postmortem cellular survival? Organs with low energy cost-of-living, such as the skin, are better suited for postmortem cellular survival. In this work, the effect of different durations of terminal phase of human life on postmortem changes in cellular gene expression was investigated using RNA sequencing data of 701 human skin samples from the Genotype-Tissue Expression (GTEx) database. Longer terminal phase (slow-death) was associated with a more robust induction of survival pathways (PI3K-Akt signaling) in postmortem skin. Such cellular survival response was associated with the upregulation of embryonic developmental transcription factors such as FOXO1 , FOXO3 , ATF4 and CEBPD . Upregulation of PI3K-Akt signaling was independent of sex or duration of death-related tissue ischemia. Analysis of single nucleus RNA-seq of post-mortem skin tissue specifically identified the dermal fibroblast compartment to be most resilient as marked by adaptive induction of PI3K-Akt signaling. In addition, slow death also induced angiogenic pathways in the dermal endothelial cell compartment of postmortem human skin. In contrast, specific pathways supporting functional properties of the skin as an organ were downregulated following slow death. Such pathways included melanogenesis and those representing the skin extracellular matrix (collagen expression and metabolism). Efforts to understand the significance of death as a biological variable (DABV) in influencing the transcriptomic composition of surviving component tissues has far-reaching implications including rigorous interpretation of experimental data collected from the dead and mechanisms involved in transplant-tissue obtained from dead donors.

Identification of a physiologic vasculogenic fibroblast state to achieve tissue repair.

Tissue injury to skin diminishes miR-200b in dermal fibroblasts. Fibroblasts are widely reported to directly reprogram into endothelial-like cells and we hypothesized that miR-200b inhibition may cause such changes. We transfected human dermal fibroblasts with anti-miR-200b oligonucleotide, then using single cell RNA sequencing, identified emergence of a vasculogenic subset with a distinct fibroblast transcriptome and demonstrated blood vessel forming function in vivo. Anti-miR-200b delivery to murine injury sites likewise enhanced tissue perfusion, wound closure, and vasculogenic fibroblast contribution to perfused vessels in a FLI1 dependent manner. Vasculogenic fibroblast subset emergence was blunted in delayed healing wounds of diabetic animals but, topical tissue nanotransfection of a single anti-miR-200b oligonucleotide was sufficient to restore FLI1 expression, vasculogenic fibroblast emergence, tissue perfusion, and wound healing. Augmenting a physiologic tissue injury adaptive response mechanism that produces a vasculogenic fibroblast state change opens new avenues for therapeutic tissue vascularization of ischemic wounds.

The dual role of boron in vitro neurotoxication of glioblastoma cells via SEMA3F/NRP2 and ferroptosis signaling pathways.

Glioblastoma multiform (GBM) is a malignant tumor cancer that originates from the star-shaped glial support tissues, namely astrocytes, and it is associated with a poor prognosis in the brain. The GBM has no cure, and chemotherapy, radiation therapy, and immunotherapy are all ineffective. A certain dose of Boric acid (BA) has many biochemical effects, conspicuously over antioxidant/oxidant rates. This article sought to investigate the modifies of various doses of BA on the glioblastoma concerning cytotoxicity, ferroptosis, apoptosis, and semaphorin-neuropilin signaling pathway. The Cytotoxic activity and cell viability of BA (0.39-25 mM) in C6 cells were tested at 24, 48, and 72 h using 3-(4,5-dimethylthiazol, 2-yl)-2,5-diphenyl tetrazolium bromide (MTT). The IC50 concentration of BA at 1.56 mM was found and cell lysate used for biochemical analysis. Glutathione peroxidase 4 (GPx4) and ACLS4 levels of ferroptosis, levels of total antioxidant (TAS) and oxidant (TAS) parameters, malondialdehyde (MDA), apoptotic proteins as caspase 3 (CASP3) and caspase 7 (CASP7) were measured. The ferroptosis, semaphoring-neuropilin, apoptotic pathway markers and cell counts were analyzed with flow cytometry, Q-PCR, Western and Elisa technique in the C6 cell lysate. BA triggered ferroptosis in the C6 cells dose-dependently, affecting the semaphorin pathway, so reducing proliferation with apoptotic compared with untreated cell as control group (p < .05). This study revealed that BA, defined as trace element and natural compound, incubated ferroptosis, total oxidant molecules, and caspase protein in a dose-dependently by disrupting SEMA3F in tumor cells.

Epigenetic basis of diabetic vasculopathy.

Type 2 diabetes mellitus (T2DM) causes peripheral vascular disease because of which several blood-borne factors, including vital nutrients fail to reach the affected tissue. Tissue epigenome is sensitive to chronic hyperglycemia and is known to cause pathogenesis of micro- and macrovascular complications. These vascular complications of T2DM may perpetuate the onset of organ dysfunction. The burden of diabetes is primarily because of a wide range of complications of which nonhealing diabetic ulcers represent a major component. Thus, it is imperative that current research help recognize more effective methods for the diagnosis and management of early vascular injuries. This review addresses the significance of epigenetic processes such as DNA methylation and histone modifications in the evolution of macrovascular and microvascular complications of T2DM.

Beta-carotene exerted anti-proliferative and apoptotic effect on malignant mesothelioma cells.

High blood levels of ß-carotene and increased intake in the diets are inversely proportional to incidence of many cancer types. Antioxidant activity of ß-carotene was proposed to be related with its antitumor effect. Despite this plant derivative substance being sought in many cancer types, the effectiveness of ß-carotene against malignant mesothelioma remained unclear. Therefore, the present study aims to explore the impact of ß-carotene on cell viability, apoptosis, and oxidative stress in mesothelioma cells. Human mesothelioma cell SPC212 were treated with ß-carotene (3.125-200 µM) for 24, 48, 72, and 96 h. Cytotoxicity was measured with the MTT assay (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide). Annexin-V/propidium iodide (PI) and caspase 3/7 biomarkers were used to identify apoptotic cells. Finally, the oxidative stress was evaluated with flow cytometry. The results of the measurements indicated a significant decline in viable mesothelioma cancer cell numbers upon ß-carotene treatment in time- and concentration-dependent manner when compared to control cells. Furthermore, ß-carotene treatment led to apoptosis induction according to both annexin V/PI and caspase 3/7 assays. Furthermore, ß-carotene increased oxidative stress in SPC212 cells. These results show how ß-carotene affects proliferative, apoptotic, and oxidative properties in SPC212 malignant pleural mesothelioma cells and provide useful insights into future studies.

The effects of thymoquinone and quercetin on the toxicity of acrylamide in rat glioma cells.

Acrylamide is a neurotoxic agent forming in foods. Thymoquinone and quercetin are plant-derived antioxidants in various foods with known benefits. C6 cells are glioblastoma cells. In this study, we aimed at preventing acrylamide toxicity by thymoquinone and quercetin in the C6 cell line. In our study, first, toxic doses of acrylamide, nontoxic doses of thymoquinone and quercetin in C6 cells for 24 h were determined by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) colorimetric test. After that, caspase 3/7 and annexin V tests were performed by flow cytometry to evaluate whether the apoptosis pathway was inducted. Furthermore, autophagy and oxidative stress were assessed by flow cytometry. The amount of Nrf2 (nuclear factor erythroid 2-related factor 2) was determined by immunocytochemistry. The morphological examination was performed by microscopic analyses. As a result, 4 mM of acrylamide was determined to be used to induce toxicity in C6 cells. The nontoxic doses of thymoquinone and quercetin were respectively determined as 3.9 and 2.0 µM. Thymoquinone and quercetin not only reduced acrylamide-induced apoptosis in annexin V and caspase 3/7 assays but also morphological deformations in microscopic examinations. In autophagy, it was revealed that acrylamide-induced autophagy was decreased by quercetin and thymoquinone pretreatments. As for Nrf2 expression, it was observed that acrylamide increased Nrf2 expression, and thymoquinone and quercetin pretreatments increased it even further. In conclusion, in the study, acrylamide demonstrated a damaging effect on C6 glioblastoma cells, and thymoquinone and quercetin pretreatments exerted a protective effect against acrylamide-induced damage in C6 cells.

Endothelial Phospholipase Cγ2 Improves Outcomes of Diabetic Ischemic Limb Rescue Following VEGF Therapy.

Therapeutic vascular endothelial growth factor (VEGF) replenishment has met with limited success for the management of critical limb-threatening ischemia. To improve outcomes of VEGF therapy, we applied single-cell RNA sequencing (scRNA-seq) technology to study the endothelial cells of the human diabetic skin. Single-cell suspensions were generated from the human skin followed by cDNA preparation using the Chromium Next GEM Single-cell 3' Kit v3.1. Using appropriate quality control measures, 36,487 cells were chosen for downstream analysis. scRNA-seq studies identified that although VEGF signaling was not significantly altered in diabetic versus nondiabetic skin, phospholipase Cγ2 (PLCγ2) was downregulated. The significance of PLCγ2 in VEGF-mediated increase in endothelial cell metabolism and function was assessed in cultured human microvascular endothelial cells. In these cells, VEGF enhanced mitochondrial function, as indicated by elevation in oxygen consumption rate and extracellular acidification rate. The VEGF-dependent increase in cell metabolism was blunted in response to PLCγ2 inhibition. Follow-up rescue studies therefore focused on understanding the significance of VEGF therapy in presence or absence of endothelial PLCγ2 in type 1 (streptozotocin-injected) and type 2 (db/db) diabetic ischemic tissue. Nonviral topical tissue nanotransfection technology (TNT) delivery of CDH5 promoter-driven PLCγ2 open reading frame promoted the rescue of hindlimb ischemia in diabetic mice. Improvement of blood flow was also associated with higher abundance of VWF+/CD31+ and VWF+/SMA+ immunohistochemical staining. TNT-based gene delivery was not associated with tissue edema, a commonly noted complication associated with proangiogenic gene therapies. Taken together, our study demonstrates that TNT-mediated delivery of endothelial PLCγ2, as part of combination gene therapy, is effective in diabetic ischemic limb rescue.

ß-Hydroxybutyrate, One of the Three Main Ketone Bodies, Ameliorates Acute Pancreatitis in Rats by Suppressing the NLRP3 Inflammasome Pathway.

BACKGROUND: Acute pancreatitis (AP) is a widespread disease resulting from the inflammation of acinar cells in the pancreas. ß-hydroxybutyrate (BHB) is a water-soluble main ketone body synthesized in the human liver. The purpose of this study was to examine the possible therapeutic effects of BHB in the experimentally-induced AP model in rats. METHODS: In our study, male rats were randomly allotted into 6 groups, as control (0.9% saline i.p.), BHB1 (200 mg/kg BHB i.p.), BHB2 (2 doses of 200 mg/kg BHB i.p.), AP (4 doses of 50 µg/kg cerulein i.p., 4 doses at 1 h intervals), AP+BHB1 and AP+BHB2 groups. In pancreatic tissue sections, immunohistochemistry staining and western blot analysis for the inflammasome complex (caspase-1, ASC, and NLRP3) and inflammation-associated proteins (TNF-α and NF-κB) and a histopathological examination were performed. The levels of lipase, amylase, interleukin (IL)-18 and IL-1ß in serum were measured. RESULTS: Several pathological degenerations, including edema, inflammatory cell infiltration, acinus necrosis, and bleeding were observed in the AP group, while the histological architecture of the control and the sham BHB1 and BHB2 groups were regular. The AP-induced pathological changes were considerably alleviated in the AP+BHB1 and AP+BHB2 groups. In the AP group, a conspicuous increase in caspase-1, ASC, NLRP3, TNF-α, and NF-κB proteins, and in the levels of amylase, lipase, IL-18, and IL-1ß were detected. BHB treatments after AP induction decreased those proteins to the level of control. CONCLUSIONS: We demonstrated that BHB has the potential to cure AP by suppressing the NLRP3 inflammasome and can be used in the treatment of many diseases which progress through the NLRP3 inflammasome.

The Protective Agents Used against Acrylamide Toxicity: An In Vitro Cell Culture Study-Based Review.

Acrylamide is a dangerous electrophile with the potency to react with many biological moieties including proteins, and nucleic acids as well as other macromolecules. Acrylamide was first only known a chemical exposed in working areas as a neurotoxicant, it was later discovered that beyond just being a neurotoxicant exposed in industrial areas, acrylamide is exposed via daily foods as well. As such, several strategies have been sought to be developed to relieve the toxic spectrum of this chemical. The utilization of a protective agent against acrylamide toxicity was one of those strategies. To date, many agents with protective potency have been investigated. Herein, we compiled these agents and their effects shown in in vitro studies. We used the search engines of Web of Knowledge and searched the keywords "acrylamide" and "protect" in the titles along with the keyword "cell" in the topics. Twenty-one directly related articles out of 35 articles were examined. Briefly, all agents used against acrylamide were reported to exhibit protective activity. In most of these reports, 5 mM concentration of acrylamide and 24-hour treatment were the employed dose and duration. Usually, the beneficial agents were pre-treated to the cells. PC12 cells were the most utilized cell line, and the mitogen-activated protein kinase (MAPK) and nuclear factor erythroid 2-related factor 2 (NRF2) pathways were the most studied pathways. This study, beside other importance, can be utilized as a guide for how the protective studies against acrylamide were done and which parameters were investigated in in vitro acrylamide studies. In conclusion, taking measures is of utmost importance to prevent or alleviate the toxicity of acrylamide, to which we are daily exposed even in our homes. Therefore, future studies should persist in focusing on mitigating acrylamide toxicity.

Cardiac hypertrophy caused by hyperthyroidism in rats: the role of ATF-6 and TRPC1 channels.

Hyperthyroidism influences the development of cardiac hypertrophy. Transient receptor potential canonical channels (TRPCs) and endoplasmic reticulum (ER) stress are regarded as critical pathways in cardiac hypertrophy. Hence, we aimed to identify the TRPCs associated with ER stress in hyperthyroidism-induced cardiac hypertrophy. Twenty adult Wistar albino male rats were used in the study. The control group was fed with standard food and tap water. The group with hyperthyroidism was also fed with standard rat food, along with tap water that contained 12 mg/L of thyroxine (T4) for 4 weeks. At the end of the fourth week, the serum-free triiodothyronine (T3), T4, and thyroid-stimulating hormone (TSH) levels of the groups were measured. The left ventricle of each rat was used for histochemistry, immunohistochemistry, Western blot, total antioxidant capacity (TAC), and total oxidant status (TOS) analysis. As per our results, activating transcription factor 6 (ATF-6), inositol-requiring kinase 1 (IRE-1), and TRPC1, which play a significant role in cardiac hypertrophy caused by hyperthyroidism, showed increased activation. Moreover, TOS and serum-free T3 levels increased, while TAC and TSH levels decreased. With the help of the literature review in our study, we could, for the first time, indicate that the increased activation of ATF-6, IRE-1, and TRPC1-induced deterioration of the Ca2+ ion balance leads to hypertrophy in hyperthyroidism due to heart failure.

Effects of astaxanthin on metastasis suppressors in ductal carcinoma. A preliminary study.

BACKGROUND: Breast cancer (BC) is a major public health problem diagnosed in more than 2 million women worldwide in 2018, causing more than 600,000 deaths. 90% of deaths due to breast cancer are caused by metastasis. Metastasis is a complex process that is divided into several steps, including separation of tumor cells from the primary tumor, invasion, cell migration, intravasation, vasculature survival, extravasation, and colonization of the secondary site. Astaxanthin (AXT) is a marine-based ketocarotenoid that has many different potential functions such as anti-oxidant, anti-inflammatory and oxidative stress-reducing properties to potentially reduce the incidence of cancer or inhibit the expansion of tumor cells. This study aims to investigate the effects of astaxanthin as a new metastasis inhibitor on T47D human invasive ductal carcinoma breast cancer cell. MATERIAL AND METHODS: To investigate the effects of the astaxanthin as a new metastasis inhibitor on T47D cell, expression levels of anti-maspin, anti-Kai1, anti-BRMS1, and anti-MKK4 were examined by western blot. Also, we evaluated differences of these suppressors expression levels in tissue sections of 10 patients diagnosed with in situ and invasive ductal carcinoma by immunohistochemistry method. RESULT: 250 µM astaxanthin increased the activation of all metastasis suppressing proteins. Also, these metastasis suppressors showed higher expression in invasive ductal carcinoma tissues than in situ ductal carcinoma patients. CONCLUSION: We think that astaxanthin is a promising therapeutic agent for invasive ductal carcinoma patients. The effects of astaxanthin on metastasis in breast cancer should be investigated further based on these results. KEY WORDS: Breast, cancer, metastasis.

Investigation of the effect of hyperthyroidism on endoplasmic reticulum stress and tran- sient receptor potential canonical 1 channel in the kidney

Background/aim: Hyperthyroidism is associated with results in increased glomerular filtration rate as well as increased renin-angio- tensin-aldosterone activation. The disturbance of Ca2+ homeostasis in the endoplasmic reticulum (ER) is associated with many diseases, including diabetic nephropathy and hyperthyroidism. Transient receptor potential canonical 1 (TRPC1) channel is the first cloned TRPC family protein. Although it is expressed in many places in the kidney, its function is uncertain. TRPC1 is involved in regulating Ca2+ homeostasis, and its upregulation increases ER Ca2+ level, activates the unfolded protein response, which leads to cellular damage in the kidney. This study investigated the role of TRPC1 in the kidneys of hyperthyroid rats in terms of ER stress markers that are gluco- se-regulated protein 78 (GRP78), activating transcription factor 6 (ATF6), (protein kinase R (PKR)-like endoplasmic reticulum kinase) (PERK), Inositol-requiring enzyme 1 (IRE1). Materials and methods: Twenty male rats were assigned into control and hyperthyroid groups (n = 10). Hyperthyroidism was induced by adding 12 mg/L thyroxine into the drinking water of rats for 4 weeks. The serum-free T3 and T4 (fT3, fT4), TSH, blood urea nitrogen (BUN), and creatinine levels were measured. The histochemical analysis of kidney sections for morphological changes and also im- munohistochemical and western blot analysis of kidney sections were performed for GRP78, ATF6, PERK, IRE1, TRPC1 antibodies. Results: TSH, BUN, and creatinine levels decreased while fT3 and fT4 levels increased in the hyperthyroid rat. The morphologic analy- sis resulted in the capillary basal membrane thickening in glomeruli and also western blot, and immunohistochemical results showed an increase in TRPC1, GRP78, and ATF6 in the hyperthyroid rat (p < 0.05). Conclusion: In conclusion, in our study, we showed for the first time that the relationship between ER stress and TRPC1, and their increased expression caused renal damage in hyperthyroid rats.

Cyproheptadine causes apoptosis and decreases inflammation by disrupting thiol/disulfide balance and enhancing the levels of SIRT1 in C6 glioblastoma cells.

Cyproheptadine is first-generation antihistamine drug, that is, H1 receptor antagonist, with a drug being anesthetic, anti-serotonergic and anti-cholinergic and started to be used clinically in the 1960s. As firstly utilized as an anti-allergic drug, usage of cyproheptadine was expanded to other cases including serotonin syndrome, appetite increasing, migraines and insomnia. However, there are almost few studies seeking to explore the association between cyproheptadine and cancer in general. In the present study, we sought to determine the impact of cyproheptadine on C6 glioblastoma cells by morphological, biochemical and cytotoxic analyzes. We searched the effective doses of cyproheptadine for C6 glioblastoma cells and examined the cells under an inverted microscope. Next, we determined the protein levels of SIRT1, NFκB and IL-6 protein. Then, we measured and calculated the levels of thiols, disulfide bonds and related parameters. After that, we evaluated apoptotic activity by Annexin V and caspase 3 assays. As a result, we detected a dose-dependent increase in apoptosis and SIRT 1 protein levels, and a decrease in inflammatory proteins. Furthermore, we have detected a drop in thiol and disulfide content. Our study suggests that Cyproheptadine causes apoptosis and decreases inflammation by disrupting thiol/disulfide balance and enhancing the levels of SIRT1, offering the potential for being an anti-cancer drug. Therefore, it might be further investigated in future studies.

Concanavalin A induces apoptosis in a dose-dependent manner by modulating thiol/disulfide homeostasis in C6 glioblastoma cells.

Glioma is the most common brain tumor. C6 rat glioblastoma cells provide the possibility to the scientist to study brain cancer. Concanavalin A (Con A) has a lot of antitumoral effects, especially over oxidative stress. In the present study, it was aimed to decide the impacts of various doses of Con A on C6 glioblastoma cells regarding cytotoxicity, thiol/disulfide homeostasis, apoptosis, and inflammation. We detected the cytotoxic activity of Con A (from 7.8 to 500 µg/ml) in C6 cells by utilizing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and determined the toxic concentration of Con A. Once the optimal doses were found, the thiol-disulfide homeostasis, levels of total antioxidant and oxidant status (TAS and TOS), malondialdehyde (MDA) and glutathione (GSH), pro-inflammatory cytokines as tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), apoptotic proteins as cytochrome c (CYCS), and caspase 3 (CASP3) were measured. Apoptotic and morphological changes in the C6 cells were examined with an inverted microscope and flow cytometry technique. Dose-dependent Con A triggered oxidative damage in the C6 cells, affecting the inflammatory pathway, so reducing proliferation with apoptotic proteins and morphological changes. But especially, Con A increased disulfide formation by disrupting the thiol/disulfide balance in C6 cells. This study revealed that Con A, known as carbohydrate-binding protein, generated oxidative damage, inflammation, and apoptosis in a dose-dependent manner by modulating thiol/disulfide homeostasis in C6 glioblastoma cells.

Bexarotene inhibits cell proliferation by inducing oxidative stress, DNA damage and apoptosis via PPARγ/ NF-κB signaling pathway in C6 glioma cells.

Gliomas are one of the most aggressive brain tumors with a poor prognosis in the central nervous system. Bexarotene is a third-generation retinoid X receptor agonist that is promising in the treatment of both cancer and neurodegenerative diseases. In this study, we aimed to investigate the cytotoxic and anti-proliferative effects of bexarotene in C6 glioma cells through the PPARγ/NF-κB pathway. In the study, first cytotoxic bexarotene concentrations for C6 cells were detected, and then apoptosis profile, reactive oxygen species (ROS), total antioxidant (TAS), 8-hydroxy-2'-deoxyguanosine (8-OHdG) and nuclear factor-κB (NF-κB) levels in the cells were determined. In addition, peroxisome proliferator-activated receptor γ (PPARγ) mRNA expression analysis was carried out. As a result, we detected concentration- and time-dependent antiproliferative effects of bexarotene on C6 cells. We found that bexarotene treatment decreased NF-κB and TAS levels and increased PPARγ and 8-OHdG levels in C6 cells. Bexarotene enhanced PPARγ expression in a dose-dependent manner when compared to the control group (P < 0.01). Furthermore, we determined that bexarotene-induced apoptotic C6 cells enhanced through Annexin V-FITC/PI staining and caspase-3/-7 activation analyses since phosphatidylserine level on the outer surface of the cell membrane and caspase-3/-7 activities were increased in the cells treated with bexarotene. In conclusion, bexarotene treatment in C6 glioma cells could modulate apoptosis profile, DNA damage, ROS production, and reduction of TAS levels through inhibition of NF-κB by enhancing PPARγ expression.