Oxidative stress and inflammatory markers in streptozotocin-induced acute and subacute toxicity response.

Streptozotocin (STZ) is used as a diabetes-inducing agent in experimental animal studies. However, it is known that STZ-induced diabetic animals show significant increases in oxidative stress parameters and neurodegeneration besides their blood glucose level. In this study, the acute and subacute toxic effects of STZ on the liver, sciatic nerve, and brain tissues were investigated in vivo rat model. Sprague-Dawley rats were divided into two groups; while 50 mg/kg STZ was administered ip to the STZ group, only saline was administered to the control group. After STZ administration, three units (100 U/mL) of subcutaneous insulin glargine were applied daily to prevent the formation of diabetes. At 24 h, 1,2, and 4 weeks after applications, rats from each group were sacrificed and tissues were removed under anesthesia. At the end of the study, compared to the control, a significant decrease in SOD and GST activity and an increase in lipid peroxidation were detected in the liver and sciatic tissues of rats in the STZ-treated group in the first 24h. Considering the TUNEL, NFκB, and NOS2 expressions, it was noted that while the effects of STZ on the liver were observed in the acute stage (24h), it had subacute effects on the brain. When apoptosis-related gene expression (Bcl-2, Bax, CASP3, CASP8, CASP9, TNF-α) and immunohistochemistry were evaluated, the apoptotic effect of STZ was observed mostly in sciatic nerve tissues. Within the scope of the study, it was revealed that STZ did not only show selective toxicity to pancreatic ß cells but also very toxic to other tissues and organs.

Preparation, characterization, and toxicity evaluation of microemulsion formulation containing prunetin for potential oral applications.

Phytochemicals as therapeutic alternatives can have a fundamental impact on the various stages of inflammation and its resolution. Prunetin is a naturally occurring isoflavone and has been claimed to have numerous therapeutic potentials. The objective of this study is preparation, characterization, and toxicity evaluation of microemulsion formulation containing prunetin (PMF) for potential oral applications. With this research, it was targeted to emphasize the way of improving the therapeutic efficacy of natural biomolecules with a nontoxic and effective formulation. In the study, the pseudo-ternary phase diagram was developed and PMF was characterized by conductivity, droplet size, viscosity and pH. Effects against to cytokines (IL-1ß and IL-6) and TNF-α levels of the PMF were determined by ELISA technique. Genotoxicity and acute oral toxicity tests were carried out according to OECD guidelines. The results showed that PMF is a colloid system that reduced proinflammatory cytokine levels in LPS-induced macrophage cells compared to the control group. PMF demonstrated no mutagenic activity against TA98, TA100, TA1535, and TA1537 Salmonella strains. The in vivo oral acute toxicity test results indicated that PMF did not show mortality or significant side effects even at 2000 mg/kg bw. This study represents PMF showed a good safety profile in animal study. It is thought that this formulation may have anti-inflammatory potential with further in vivo testing.

Impact of a Polymer-Based Nanoparticle with Formoterol Drug as Nanocarrier System In Vitro and in an Experimental Asthmatic Model.

The implementation of nanotechnology in pulmonary delivery systems might result in better and more specific therapy. Therefore, a nano-sized drug carrier should be toxicologically inert and not induce adverse effects. We aimed to investigate the responses of a polymer nano drug carrier, a lysine poly-hydroxyethyl methacrylate nanoparticle (NP) [Lys-p(HEMA)], loaded with formoterol, both in vitro and in vivo in an ovalbumin (OVA) asthma model. The successfully synthesized nanodrug formulation showed an expectedly steady in vitro release profile. There was no sign of in vitro toxicity, and the 16HBE and THP-1 cell lines remained vital after exposure to the nanocarrier, both loaded and unloaded. In an experimental asthma model (Balb/c mice) of ovalbumin sensitization and challenge, the nanocarrier loaded and unloaded with formoterol was tested in a preventive strategy and compared to treatment with the drug in a normal formulation. The airway hyperresponsiveness (AHR) and pulmonary inflammation in the bronchoalveolar lavage (BAL), both cellular and biochemical, were assessed. The application of formoterol as a regular drug and the unloaded and formoterol-loaded NP in OVA-sensitized mice followed by a saline challenge was not different from the control group. Yet, both the NP formulation and the normal drug application led to a more deteriorated lung function and increased lung inflammation in the OVA-sensitized and -challenged mice, showing that the use of the p(HEMA) nanocarrier loaded with formoterol needs more extensive testing before it can be applied in clinical settings.

L-glutamic acid-g-poly hydroxyethyl methacrylate nanoparticles: acute and sub-acute toxicity and biodistribution potential in mice.

The aim of this safety study in mice was to determine in vivo toxicity and biodistribution potential of a single and multiple doses of L-glutamic acid-g-p(HEMA) polymeric nanoparticles as a drug delivery system. The single dose did not cause any lethal effect, and its acute oral LD50 was >2.000 mg/kg body weight (bw). Multiple doses (25, 50, or 100 mg/kg bw) given over 28 days resulted in no significant differences in body and relative organ weights compared to control. These results are supported by biochemical and histological findings. Moreover, nanoparticle exposure did not result in statistically significant differences in micronucleus counts in bone marrow cells compared to control. Nanoparticle distribution was time-dependent, and they reached the organs and even bone marrow by hour 6, as established by ex vivo imaging with the IVIS® spectrum imaging system. In conclusion, L-glutamic acid-g-p(HEMA) polymeric nanoparticles appear biocompatible and have a potential use as a drug delivery system.

Fluvastatin alleviates doxorubicin-induced cardiac and renal toxicity in rats via regulation of oxidative stress, inflammation, and apoptosis associated genes expressions.

Doxorubicin (DOXO) is a cytostatic agent used in the chemotherapy protocol of several cancers for more than 40 years, but usage of this drug in cancer treatment has been limited due to severe renal and cardiac tissue toxicities that may result in death in patients. Fluvastatin (FV) is a fully synthetic hydroxymethyl glutaryl coenzyme A (HMG-CoA) reductase inhibitor used as a cholesterol-lowering agent in patients with hypercholesterolemia. Previous studies revealed that FV also exhibits antioxidant, anti-inflammatory, and antitumor activity. Additionally, our previous study indicated that FV exerts a prophylactic effect on DOXO-induced testicular toxicity by preventing lipid peroxidation, supporting the antioxidant system, and regulating the blood-testis barrier-associated genes expression. Herein, we purposed to evaluate the possible therapeutic and the protective effects of FV on the DOXO-induced cardiac and renal toxicitiy model by histochemical, immunohistochemical, biochemical, and real-time polymerase chain reaction (real-time PCR) analyses. Results point out protective use of FV exerts a beneficial effect by repressing lipid peroxidation and by regulating the inducible nitric oxide synthase (iNOS), nitric oxide synthase endothelial (eNOS), nuclear factor kappa-B (NF-κB), and Caspase-3 (Casp3) protein and mRNA expressions, which play an important role in mediating DOXO-induced renal and cardiac toxicity mechanisms. In conclusion, FV may be a candidate agent for the prevention of renal and cardiac toxicities in cancer patients receiving DOXO chemotherapy.

Is losartan a promising agent for the treatment of type 1 diabetes-induced testicular germ cell apoptosis in rats?

BACKGROUND: Diabetes mellitus (DM) is common metabolic disease that poses a major risk to public health and fertility. Previous studies indicate that DM may cause male infertility by triggering oxidative stress and germ cell apoptosis in the testis. Due to the undesirable effects of known antidiabetic drugs, scientists have begun to investigate the use of alternative drugs to control infertility complications observed in men. In this context, present study aimed to investigate the possible antiapoptotic effect of losartan against DM-induced testicular germ cell apoptosis. METHODS AND RESULTS: Expreimental DM model was induced by intraperitoneal injection of streptozocin (STZ, 55 mg/kg) to 28 rats, which were then randomly assigned to 4 groups; 1 mL saline solution was given to DM + saline group by oral gavage, 5 mg/kg/day oral losartan was given to DM + low-dose losartan, 20 mg/kg/day oral losartan was given to DM + mid-dose losartan and, 80 mg/kg/day oral losartan was given to DM + high-dose losartan group for 4 weeks. Bax, Bcl-2 and cleaved-Caspase 3 immunoexpression, terminal-deoxynucleotidyl transferase dutp nick end labeling (TUNEL), Annexin-V and Real Time PCR analyses performed to evaluate antiapoptotic effects of losartan on diabetic rats' testis. In addition, biochemical analyzes carried out to evaluate change in oxidative stress. CONCLUSION: The results showed that losartan may have dose-related antiapoptotic effects on rats' testis via decreasing oxidative stress.

How Safe Is the Use of Intrathecal Vancomycin?

BACKGROUND: Central nervous system infection after neurosurgical procedures is a severe complication with high morbidity rates and sometimes mortality. Our experimental study aimed to investigate the biochemical and histopathologic effects of vancomycin on neural tissues when applied to the cisterna magna. METHODS: Wistar albino rats were randomly divided into 4 groups: Control (Group 1) and different vancomycin dose groups (Groups 2, 3, and 4). In Group 1, 0.1 mL cerebrospinal fluid was drained from the cisterna magna and 0.1 mL 0.9% NaCI (normal saline) was administered into the subarachnoid space. In the study groups, 0.1 mL cerebrospinal fluid was drained from the cisterna magna and 0.1 mg/200g rat per day (Group 2), 0.2 mg/200g rat per day (Group 3), and 0.4 mg/200g rat per day (Group 4) vancomycin were administered into the subarachnoid space for 7 days. All rats were sacrificed on the eighth day. Serum superoxide dismutase and catalase levels were measured. Histopathologic and immunohistochemical analyses were conducted. RESULTS: The findings showed that the administration of 0.2 and 0.4 mg/kg doses had significant differences in superoxide dismutase and catalase activity compared with the controls (P < 0.05). These vancomycin doses also induced the apoptotic process, and the enzyme activity results correlated with immunohistochemical results. CONCLUSIONS: Dose-related neurotoxicity of intrathecal vancomycin was shown at the cellular level. The importance of dose regulation of intrathecal vancomycin has come into view. To our knowledge, this is the first study in the literature that has investigated the neurotoxic effects of vancomycin.

The neuro-restorative effect of adipose-derived mesenchymal stem cell transplantation on a mouse model of diabetic neuropathy.

Diabetic neuropathy (DN) is the most common degenerative complication associated with Diabetes Mellitus. Despite widespread awareness about DN, the only effective treatments are blood glucose control and pain management. The aim of the current study was to determine the effect of intramuscular adipose-derived mesenchymal stem cell (AMSC) transplantation on sciatic nerves in DN using EMG and histological analyses. A total of 27 mice were randomly divided into three groups: control group, DN group and AMSC group. In EMG, CMAP amplitude in the sciatic nerves was lower, but distal latency was higher in the DN group compared with the control group. CMAP amplitude in the sciatic nerves was higher in the AMSC group compared with the DN group. Distal latency in the sciatic nerve was lower in the AMSC group compared with the DN group. Histologic examination of the tissues in the animals treated with AMSC showed a remarkable improvement in microscopic morphology. Fluorescence microscopy analyses demonstrated that intramuscularly transplanted AMSC was selectively localized in the sciatic nerves. Transplantation of AMSC increased protein expression of S100, cdk2, NGF and DHH, all of which, interfered with DN onset in sciatic nerves. The findings of the present study suggest that AMSC transplantation improved DN through a signal-regulatory effect on Schwann cells, neurotrophic actions and restoration of myelination.

Ameliorative effect of edible Halopteris scoparia against cadmium-induced reproductive toxicity in male mice: A biochemical and histopathologic study.

Cadmium (Cd) is a toxic metal affecting the reproductive system. Halopteris scoparia (brown algae) is generally consumed as a salad in the Far East countries. This study was conducted to compare and determine the possible protective effects of H. scoparia and vitamin E and C combination (VEC) against cadmium chloride (CdCl2 )-induced reproductive toxicity. A total of 36 male mice were equally divided into as control, CdCl2 (2 mg/kg), CdCl2  + H. scoparia (900 mg/kg), CdCl2  + VEC (200 mg/kg), H. scoparia alone and VEC alone groups. Blood and testis samples were taken for biochemical, histochemical and immunohistochemical analyses. H. scoparia was also examined for antioxidant activity (by DPPH assay) and mineral/trace element content (by ICP-MS method). CdCl2 exposure caused a significant deterioration in body weight, sperm parameters (count, motility, viability and morphology) (p < .001), histopathology, immunoreactivity and testosterone levels. However, H. scoparia improved CdCl2 -induced deterioration effects more successfully than VEC-treated group. The present study suggests that edible H. scoparia can be used as a natural protective agent against Cd-induced testicular damage by possibly enhancing essential element levels or increasing antioxidant defence system.

Mid-dose losartan mitigates diabetes-induced hepatic damage by regulating iNOS, eNOS, VEGF, and NF-κB expressions

Background/aim: Losartan, an antihypertensive drug, is highly preferred in patients with diabetes mellitus (DM) and hypertension because of its retarding effect on diabetic nephropathy. In this study, we investigated the potential therapeutic effect of different doses of losartan on hepatic damage in a streptozotocin (STZ, 50 mg/kg)-induced DM model in rats. Materials and methods: In this study, five different groups were formed: control, DM, low-dose losartan (5 mg/kg), mid-dose losartan (20 mg/kg), and high-dose losartan (80 mg/kg). Liver tissues of experimental groups were evaluated immunohistochemically for TUNEL, iNOS, eNOS, VEGF, and NF-κB pathways. In addition to immunohistochemical analysis, analyses of SOD and MDA, which are oxidative stress markers, were also performed and the results were evaluated together. Results: When biochemical and immunohistochemical findings were evaluated together, it was found that the results obtained from the mid-dose losartan group were closer to those of the control than the other groups. Conclusion: This study indicated that mid-dose losartan administration may have a therapeutic effect by inhibiting apoptosis and regulating iNOS, eNOS, VEGF, and NF-κB protein expressions in DM-induced hepatic damage.

Fluvastatin attenuates doxorubicin-induced testicular toxicity in rats by reducing oxidative stress and regulating the blood-testis barrier via mTOR signaling pathway.

Doxorubicin (DOX) is an anthracycline derivative antibiotic that still frequently used in the treatment of solid tumors and hematological malignancies. The clinical use of DOX is largely restricted due to acute and chronic renal, cardiac, hematological, and testicular toxicities. Previous studies have indicated that oxidative stress, lipid peroxidation, and apoptosis in germ cells are the main factors in DOX-induced testicular toxicity, but the entire molecular mechanisms that responsible for DOX-induced testicular damage are not yet fully understood. Fluvastatin is a cholesterol-lowering agent that acts by inhibiting hydroxylmethyl glutaryl coenzyme A, the key enzyme for cholesterol biosynthesis. In addition to its cholesterol-lowering effect, fluvastatin showed an antioxidant effect by cleaning hydroxyl and superoxide radicals and this drug could have a protective effect by acting on the mammalian target of rapamycin (mTOR) signal pathway in testicular damage caused by obesity. This study aimed to investigate the possible protective and therapeutic effects of fluvastatin on the DOX-induced testicular toxicity model by histochemical, immunohistochemical, biochemical, and real-time polymerase chain reaction analyses. The present study indicates that fluvastatin may have a protective and therapeutic effect by removing reactive oxygen species and by regulating the mTOR, connexin 43, and matrix metalloproteinase 9 protein and messenger ribonucleic acid expressions, which play an important role in regulating the blood-testis barrier. On the other hand, the use of fluvastatin as a protective/prophylactic agent was found to be more effective than the use of this drug for treatment. In light of this information, fluvastatin may be a candidate agent that can be used to prevent testicular toxicity observed in men receiving DOX treatment.

Apoptosis-inducing activities of Halopteris scoparia L. Sauvageau (Brown algae) on cancer cells and its biosafety and antioxidant properties.

The aim of this study was to reveal the biological activities and in vivo toxicity profiles of n-hexane, chloroform and methanol extracts of brown algae Halopteris scoparia L. Sauvageau. In this study, extracts were tested for their phytochemical contents and antioxidant activities. The cytotoxic activities of the extracts against cervical adenocarcinoma (HeLa), colon colorectal adenocarcinoma (CaCo-2) and breast adenocarcinoma (MCF7) cells were assessed by MTT assay and total RNAs derived from cell lines to analyze gene expression were analyzed by Real Time Ready Human Apoptosis Panel 96. Also, in vivo toxicity and irritation effects of extracts were evaluated by LD50 acute toxicity test and Hen's egg test chorioallantoic membrane (HET-CAM) assay, respectively. Our results showed that the phenolic and flavonoid contents were determined only in methanol extract (33.20 ± 1.41 mg GAE/g and 1.26 ± 0.95 mg QE/g). Also, n-hexane has a broader spectrum of content than methanol and chloroform extracts. Furthermore, n-hexane extract in DPPH and methanol extract in ABTS+ exhibited the best antioxidant activity. In addition, MTT results revealed that each three extracts cause a significant reduction in cell viability, especially in HeLa cells. When the apoptotic gene expressions were examined after treatment of extracts, the expression of many pro-apoptotic genes in both caspase-independent and caspase-dependent intrinsic and extrinsic pathways increased. These findings suggest that, considering that it had not led to irritation and toxicity in vivo, edible H. scoparia is a natural antioxidant and its apoptotic/cytotoxic activities can potentially be used against human cancers.

In vivo performance of different scaffolds for dental pulp stem cells induced for odontogenic differentiation.

This study was designed to determine the in vivo performance of three different materials as scaffolds for dental pulp stem cells (DPSC) undergoing induced odontogenic differentiation. An odontogenic medium modified by the addition of recombinant human bone morphogenetic protein 2 was used in the experimental groups to induce differentiation. Mesenchymal stem cell medium was used in the control groups. DPSC were transplanted onto the backs of mice via three scaffolds: copolymer of L-lactide and DL-lactide (PLDL), copolymer of DL-lactide (PDL) and hydroxyapatite tricalcium phosphate (HA/TCP). The expression levels of dentin sialo-phosphoprotein (DSPP), dentin matrix protein-1 (DMP1), enamelysin/matrix metalloproteinase 20 (MMP20) and phosphate-regulating gene with homologies to endopeptidases on X chromosome (PHEX) were analysed using RT-PCR. The expressions in the experimental groups were compared to those in the control groups. The transcript expressions at 6 and 12 weeks were significantly different for all scaffolds (p < 0.05), except for the expression of DSPP in the PLDL group with regard to the time variable. Although there was a decrease in the expression of enamelysin/MMP20 in PLDL and HA/TCP at 12 weeks, all other expressions increased and reached their highest level at 12 weeks. The highest DSPP expression was in the PDL group (p < 0.05). The highest expression of DMP1 was detected in the HA/TCP group (p < 0.05). The highest expression of PHEX was in the PLDL group (p < 0.05). Consequently, PLDL and PDL seemed to be promising scaffold candidates for odontogenic regeneration at least as HA-TCP, when they were applied with the DPSC induced for odontogenic differentiation.

Medium modification with bone morphogenetic protein 2 addition for odontogenic differentiation

Abstract The aim of this study was to evaluate whether medium modification improves the odontogenic differentiation of human dental pulp stem cells (DPSC) in vitro and in vivo. DPSC isolated from human impacted third molar teeth were analysed for clusters of differentiation with flow cytometry. Odontogenic differentiation was stimulated by medium modification with the addition of bone morphogenetic protein 2 (BMP2). The expression of dentin sialophosphoprotein, dentin matrix protein 1, enamelysin/matrix metalloproteinase 20 and the phosphate-regulating gene with homologies to endopeptidases on the X chromosome of the cells were analysed with RT-PCR at 7, 14 and 21 days. Then, DPSC were transplanted on the back of immunocompromised mice via a hydroxyapatite tricalcium phosphate scaffold, and the structure of the formed tissue was investigated. The cells were identified as mesenchymal stem cells with a 98.3% CD73 and CD90 double-positive cell rate. The increase in mineralization capacity and expression of human enamel-dentin specific transcripts proportional to the culture period were determined after differentiation. Six weeks after transplantation, an osteo-dentin matrix was formed in the group in which odontogenic differentiation was stimulated, and the odontogenic characteristics of the matrix were confirmed by histological examination and RT-PCR analysis. Odontogenic differentiation of the isolated and characterized human DPSC was improved with medium modification by the addition of BMP2 in vitro and in vivo. The defined medium and applied technique have a potential use for forming reparative dentin in the future, but the effects of the method should be investigated in long-term studies.

In vivo performance of different scaffolds for dental pulp stem cells induced for odontogenic differentiation

Abstract This study was designed to determine the in vivo performance of three different materials as scaffolds for dental pulp stem cells (DPSC) undergoing induced odontogenic differentiation. An odontogenic medium modified by the addition of recombinant human bone morphogenetic protein 2 was used in the experimental groups to induce differentiation. Mesenchymal stem cell medium was used in the control groups. DPSC were transplanted onto the backs of mice via three scaffolds: copolymer of L-lactide and DL-lactide (PLDL), copolymer of DL-lactide (PDL) and hydroxyapatite tricalcium phosphate (HA/TCP). The expression levels of dentin sialo-phosphoprotein (DSPP), dentin matrix protein-1 (DMP1), enamelysin/matrix metalloproteinase 20 (MMP20) and phosphate-regulating gene with homologies to endopeptidases on X chromosome (PHEX) were analysed using RT-PCR. The expressions in the experimental groups were compared to those in the control groups. The transcript expressions at 6 and 12 weeks were significantly different for all scaffolds (p < 0.05), except for the expression of DSPP in the PLDL group with regard to the time variable. Although there was a decrease in the expression of enamelysin/MMP20 in PLDL and HA/TCP at 12 weeks, all other expressions increased and reached their highest level at 12 weeks. The highest DSPP expression was in the PDL group (p < 0.05). The highest expression of DMP1 was detected in the HA/TCP group (p < 0.05). The highest expression of PHEX was in the PLDL group (p < 0.05). Consequently, PLDL and PDL seemed to be promising scaffold candidates for odontogenic regeneration at least as HA-TCP, when they were applied with the DPSC induced for odontogenic differentiation.

Viper venom induced inflammation with Montivipera xanthina (Gray, 1849) and the anti-snake venom activities of Artemisia absinthium L. in rat.

The present study was conducted to explore the characterization of Montivipera xanthina crude venom partially by in vitro and in vivo and the anti-snake venom activities of Artemisia absinthium L. in comparison with carrageenan-induced acute inflammation model in rats. The LD50 value was estimated as 8.78 mg/kg within 24 h by different venom doses administrated intraperitoneally in mice. The IC50 value was 0.43 ± 0.18 µg/ml after 48 h treatment while the calculated value was 0.73 ± 0.10 µg/ml for the culture media totally refreshed after 2 h treatment with venom. Wistar rats were treated intraperitoneally with A. absinthium extract, 30 min before venom or carrageenan was injected subplantarly into the left hind paw. Intraperitoneal administration of 25 and 50 mg/kg extract was inhibited venom induced paw swelling at 0.5, 1, 2 and 3 h (p < 0.05) while 12.5, 25 and 50 mg/kg extract treatment was inhibited carrageenan-induced paw swelling at 2, 3, 4 and 5 h (p < 0.05). In conclusion, the in vivo toxicity and inflammatory actions and in vitro cytotoxic actions of crude M. xanthina venom were performed as a first report and inhibition of venom-induced inflammation by methanolic extract of A. absinthium was described.