Amantadine mitigates the cytotoxic and genotoxic effects of doxorubicin in SH-SY5Y cells and reduces its mutagenicity.

Amantadine (AMA) is a useful drug in neuronal disorders, but few studies have been performed to access its toxicological profile. Conversely, doxorubicin (Dox) is a well-known antineoplastic drug that has shown neurotoxic effects leading to cognitive impairment. The aims of this study are to evaluate the cytotoxic, genotoxic, and mutagenic effects of AMA, as well as its possible protective actions against deleterious effects of Dox. The Salmonella/microsome assay was performed to assess mutagenicity while cytotoxicity and genotoxicity were evaluated in SH-SY5Y cells using MTT and comet assays. Possible modulating effects of AMA on the cytotoxicity, genotoxicity, and mutagenicity induced by Dox were evaluated through cotreatment procedures. Amantadine did not induce mutations in the Salmonella/microsome assay and decreased Dox-induced mutagenicity in the TA98 strain. AMA reduced cell viability and induced DNA damage in SH-SY5Y cells. In cotreatment with Dox, AMA attenuated the cytotoxicity of Dox and showed an antigenotoxic effect. In conclusion, AMA does not induce gene mutations, although it has shown a genotoxic effect. Furthermore, AMA decreases frameshift mutations induced by Dox as well as the cytotoxic and genotoxic effects of Dox in SH-SY5Y cells, suggesting that AMA can interfere with Dox mutagenic activity and attenuate its neurotoxic effects.

Genotoxic and antiproliferative properties of Endopleura uchi bark aqueous extract.

The bark extract from Endopleura uchi has been widely used in traditional medicine to treat gynecological-related disorders, diabetes, and dyslipidemias albeit without scientific proof. In addition, E. uchi bark extract safety, especially regarding mutagenic activities, is not known. The aim of this study was to determine the chemical composition, antitumor, and toxicological parameters attributed to an E. uchi bark aqueous extract. The phytochemical constitution was assessed by colorimetric and chromatographic analyzes. The antiproliferative effect was determined using sulforhodamine B (SRB) assay using 4 cancer cell lines. Cytotoxic and genotoxic activities were assessed utilizing MTT and comet assays, respectively, while mutagenicity was determined through micronucleus and Salmonella/microsome assays. The chromatographic analysis detected predominantly the presence of gallic acid and isoquercitrin. The antiproliferative effect was more pronounced in human colon adenocarcinoma (HT-29) and human breast cancer (MCF-7) cell lines. In the MTT assay, the extract presented an IC50 = 39.1 µg/ml and exhibited genotoxic (comet assay) and mutagenic (micronucleus test) activities at 20 and 40 µg/ml in mouse fibroblast cell line (L929) and mutagenicity in the TA102 and TA97a strains in the absence of S9 mix. Data demonstrated that E. uchi bark possesses bioactive compounds which exert cytotoxic and genotoxic effects that might be associated with its antitumor potential. Therefore, E. uchi bark aqueous extract consumption needs to be approached with caution in therapeutic applications.

Morphine decreases cytotoxicity and mutagenicity of doxorubicin in vitro: Implications for cancer chemotherapy.

Morphine is the most common opioid analgesic administered to treat pain in patients undergoing cancer chemotherapy. This study aimed to evaluate the cytotoxic and mutagenic effects of morphine alone and in combination with doxorubicin (Dox), an antineoplastic agent largely used in patients with solid cancers. Cytotoxicity was evaluated in neuroblastoma (SH-SY5Y) and fibroblast (V79) cells using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay while mutagenicity was assessed using the Salmonella/microsome assay in the absence and in the presence of S9 mix. Morphine showed a cytotoxic effect mainly on SH-SY5Y cells and reduced the cytotoxic effects of Dox when evaluated in a co-treatment procedure. In the Salmonella/microsome assay, it was observed that morphine did not induce mutations and, in fact, decreased the mutagenic effects induced by Dox in TA98 and TA102 strains in the absence of metabolic activation. Furthermore, in the presence of metabolic activation, no induction of mutations was observed with morphine. In conclusion, morphine decreased Dox cytotoxicity in both neuronal and non-neuronal cells and showed antimutagenic effects in the TA102 strain which detects mutagens inducing DNA oxidative damages. However, morphine decreased frameshift mutations induced by Dox in non-cytotoxic concentrations, an effect suggesting interference of Dox intercalation activity that could decrease its chemotherapeutic efficacy. These compelling findings highlight the importance of conducting further studies to explore the potential implications of co-administering morphine and Dox during cancer chemotherapy.

Toxicological potential of Aloysia gratissima: Insights from chemical analysis and in vitro studies.

ETHNOPHARMACOLOGICAL RELEVANCE: Aloysia gratissima leaves are popularly used to treat respiratory, digestive, and nervous system disorders. Several studies have been carried out to determine the biological activity of A. gratissima, such as its antibacterial and anti-edematogenic activities, but despite the beneficial uses of A. gratissima, few studies have examined the toxicological profile of this plant. AIM OF THE STUDY: This study aimed to determine the chemical composition, cytotoxic, genotoxic, mutagenic potential, and antioxidant activity of an aqueous extract of A. gratissima leaves (AG-AEL). MATERIAL AND METHODS: The phytochemical constitution of AG-AEL was assessed by colorimetric analyses and High-performance liquid chromatography (HPLC). The inorganic elements were detected by Particle-Induced X-ray Emission (PIXE). The antioxidant, cytotoxicity, genotoxic, and mutagenic activities were evaluated in vitro by Di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH), Sulforhodamine B (SRB) assay, comet assay, and Salmonella/microsome assays. RESULTS: AG-AEL indicated the presence of terpenoids, flavonoids, and phenolic acids. HPLC detected rutin at 2.41 ± 0.33 mg/100 mg. PIXE analysis indicated the presence of Mg, Si, P, S, K, Ca, Mn, and Zn. The 50% inhibitory concentration was 84.17 ± 3.17 µg/mL in the DPPH assay. Genotoxic effects were observed using the Comet assay in neuroblastoma (SH-SY5Y) cells and mutations were observed in TA102 and TA97a strains. The extract showed cytotoxic activities against ovarian (OVCAR-3), glioblastoma (U87MG), and colon (HT-29) cancer cell lines. CONCLUSIONS: In conclusion, AG-AEL increased DNA damage, induced frameshift, and oxidative mutations, and showed cytotoxic activities against different cancer cells. The in vitro toxicological effects observed suggest that this plant preparation should be used with caution, despite its pharmacological potential.

Melatonin Attenuates Inflammation, Oxidative Stress, and DNA Damage in Mice with Nonalcoholic Steatohepatitis Induced by a Methionine- and Choline-Deficient Diet.

Nonalcoholic steatohepatitis (NASH) is a disease with a high incidence worldwide, but its diagnosis and treatment are poorly managed. In this study, NASH pathophysiology and DNA damage biomarkers were investigated in mice with NASH treated and untreated with melatonin (MLT). C57BL/6 mice were fed a methionine- and choline-deficient (MCD) diet for 4 weeks to develop NASH. Melatonin was administered at 20 mg/kg during the last 2 weeks. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were measured, and hepatic tissue was dissected for histological analysis, evaluation of lipoperoxidation, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), as well as nuclear factor-erythroid 2 (Nrf2), tumor necrosis factor alpha (TNF-α), inducible nitric oxide synthase (iNOS), and transforming growth factor beta (TGF-ß) expression by immunohistochemistry. DNA damage was evaluated using Comet assay, while a micronucleus test in bone marrow was performed to assess the genomic instability associated with the disease. Melatonin decreased AST and ALT, liver inflammatory processes, balloonization, and fibrosis in mice with NASH, decreasing TNF-α, iNOS, and TGF-ß, as well as oxidative stress, shown by reducing lipoperoxidation and intensifying Nrf2 expression. The SOD and GPx activities were increased, while CAT was decreased by treatment with MLT. Although the micronucleus frequency was not increased in mice with NASH, a protective effect on DNA was observed with MLT treatment in blood and liver tissues using Comet assay. As conclusions, MLT slows down the progression of NASH, reducing hepatic oxidative stress and inflammatory processes, inhibiting DNA damage via anti-inflammatory and antioxidant actions.

Evaluation of the efficacy and toxicity of oral and topical pumpkin oil on the hair growth of mice.

This study aimed to evaluate the efficacy and safety of a topical and oral administration of pumpkin seed oil (PSO) on the hair growth of BALB/c male mice. The animals had their dorsal area shaved (2 ×2 cm) and they were divided into 6 experimental groups. They received orally saline (OS), finasteride (F), or PSO (OP) for 14 days; or topically saline (TS), minoxidil (M), or PSO (TP) for 7 days. The euthanasia of all of the mice occurred on the 22nd day, and the histological slides from the skin area were analyzed. Lipoperoxidation in the liver was assessed through the TBARS method and was also evaluated by the antioxidant enzymes (SOD and CAT). The comet assay and the micronucleus tests were performed for genotoxic/mutagenic safety analyses. A significant increase in the number of hair follicles in the TP group was seen (8.8 ± 0.8) but it was disorganized, with loose dermal collagen. Finasteride presented a significant increase in the levels of the TBARS, SOD, and CAT in the liver, and M increased the DNA damage in the blood and the liver tissues. PSO did not induce any significant changes. In addition, PSO did not induce genotoxic or mutagenic effects. In conclusion, the oral PSO for 14 days acted in the proliferation of the hair follicles, without toxicity signals in the liver. DATA AVAILABILITY: The authors confirm that all of the relevant data is included in the article and/or in the supplementary information file.

Evaluation of toxicological aspects of three new benzoxazole compounds with sunscreen photophysical properties using in silico and in vitro methods.

Sunscreening chemicals protect against damage caused by sunlight most absorbing UVA or UVB radiations. In this sense, 2-(2'-hydroxyphenyl)benzoxazole derivatives with amino substituents in the 4' and 5' positions have an outstandingly high Sun Protection Factor and adequate photostability, but their toxicity is not yet known. This study aimed to evaluate the toxicity of three synthetic 2-(2'-hydroxyphenyl)benzoxazole derivatives for their possible application as sunscreens. In silico tools were used in order to assess potential risks regarding mutagenic, carcinogenic, and skin sensitizing potential. Bioassays were performed in L929 cells to assess cytotoxicity in MTT assay and genotoxic activities in the Comet assay and micronucleus test. Also, the Salmonella/microsome assay was performed to evaluate gene mutations. The in silico predictions indicate a low risk of mutagenicity and carcinogenicity of the compounds while the skin sensitizing potential was low or inconclusive. The 2-(4'-amino-2'-hydroxyphenyl)benzoxazol compound was the most cytotoxic and genotoxic among the compounds evaluated in L929 cells, but none induced mutations in the Salmonella/microsome assay. The amino substituted at the 4' position of the phenyl ring appears to have greater toxicological risks than substituents at the 5' position of 2-(phenyl)benzoxazole. The findings warrant further studies of these compounds in cosmetic formulations.

Photobiomodulation intervention improves oxidative, inflammatory, and morphological parameters of skeletal muscle in cirrhotic Wistar rats.

Photobiomodulation (PBM) might be an intervention method to mitigate sarcopenia in cirrhotic patients. Given the lack of research on this issue, the goal of this study was to evaluate possible beneficial effects of PBM on the structural and functional properties of skeletal muscle from cirrhotic rats. Cirrhosis was induced by secondary bile duct ligation (BDL). Wistar rats were randomized into four groups: sham-operated control (Sham), Sham + PBM, BDL, and BDL + PBM. After cirrhosis induction, a dose of PBM (1 J; 100mW; 10 s; 880 nm; 6 × per week) was applied to each quadriceps, from the 15th to the 45th day after surgery. The locomotor ability was performed using an open-field task. The muscle structure was analyzed using histological methods. Cell damage was also evaluated assessing oxidative stress and DNA damage markers, and IL-1ß pro-inflammatory interleukin by immunohistochemical analysis. An increase in the number of crossings was observed in the BDL + PBM group in relation to BDL. The BDL group showed muscle atrophy and increased IL-1ß in relation to Sham, while in the BDL + PBM group, the fiber muscle was restructured and there was a decrease of IL-1 ß. TBARS increased in the liver and muscle tissues in the BDL group and decreased it in the BDL + PBM group. SOD increased while CAT decreased in the BDL + PBM group in relation to the BDL group. No genotoxic or mutagenic effect was observed for PBM treatment. PBM improved the locomotion and the morphology of the muscle fibers, decreasing oxidative stress and inflammation, without causing DNA damage in cirrhotic rats.

A study on 2-(2'-hydroxyphenyl) benzoxazoles derivatives as potential organic UV filters, Part I

Abstract Damage resulting from the incidence of ultraviolet (UV) radiation on the skin is common nowadays, with UVB (290-320 nm) and UVA (320-400 nm) radiation responsible for photoaging, sunburn and carcinogenesis. For this reason, sunscreens represent products of growing interest to prevent such damage. However, there are few organic filters marketed worldwide with photostability and effectiveness at wavelengths greater than 340 nm (long UVA), which justifies the exploration for new compounds. In this work, we determined the photostability and sun protection factor (SPF) of three 2-(2'-hydroxyphenyl)benzoxazole derivative dyes in order to develop new organic UV filters. UV-vis spectrophotometry has high level of reproducibility when compared with in vivo human clinical methods. Solubility determinations were performed in different solvents. The compounds absorbed UVA and UVB radiation, with maximum absorption wavelengths ranging from 336 to 374 nm. Photostability was evaluated using a solar simulator (3 J.m2.s-1 UVA radiation) for a maximum of 3 h. The 2-(amino-2'-hydroxyphenyl) benzoxazoles showed higher photostability than the acetylated derivative under the evaluated conditions. The three benzoxazoles presented SPF values of around 40 and preliminary results indicate that they show suitable properties to act as good chemical filters in photoprotective formulations.

Sarcopenia, oxidative stress and inflammatory process in muscle of cirrhotic rats - Action of melatonin and physical exercise.

Sarcopenia is one of the most common features of cirrhosis, contributing to morbidity and mortality in this population. We aimed to evaluate the effect of melatonin (MLT) and exercise (EX) on the quadriceps muscle in rats with biliary cirrhosis induced by bile duct ligation (BDL). We used 48 males (mean weight = 300 g), divided into eight groups. A 20 mg/Kg MLT dose was administered via i.p. (1 x daily), and the EX, the animals were set to swim in couples for 10 min each day. Upon completion, blood, liver, and quadriceps samples were taken for analysis. In the liver enzymes analysis and comet assay results, a reduction was observed in the groups treated with MLT with/or EX comparing to the BDL group. In the evaluation of substances that react to thiobarbituric acid (TBARS), nitric oxide levels (NO), and tumor necrosis factor-alpha levels (TNF-α), there was a significant increase in the BDL group and a reduction in the treated groups. In the activity of the superoxide dismutase enzyme (SOD) and interleukin-10 levels (IL-10) concentrations, there was a significant increase in the treated groups of the BDL group. Histological analysis revealed muscle hypotrophy in the BDL group in comparison with the control group (CO) and increased muscle mass in the treated groups. There was an increase in weight gain and phase angle in the groups treated with MLT with/or EX comparing to the BDL group. We suggest that treatments may contribute to the reduction of muscle changes in cirrhotic patients.

Targeting thymidine phosphorylase inhibition in human colorectal cancer xenografts.

Human thymidine phosphorylase (hTP) is overexpressed in several solid tumors and is commonly associated with aggressiveness and unfavorable prognosis. 6-(((1,3-Dihydroxypropan-2-yl)amino)methyl)-5-iodopyrimidine-2,4(1H,3H)-dione (CPBMF-223) is a noncompetitive hTP inhibitor, which has been described as a tumor angiogenesis inhibitor. The present study investigated the effects of CPBMF-223 in a xenograft tumor induced by human colorectal carcinoma cells (HCT-116). Additionally, CPBMF-223 capacity to reduce cell migration, its toxicological profile, and pharmacokinetic characteristics, were also evaluated. The intraperitoneal treatment with CPBMF-223 markedly prevented the relative tumor growth with an efficacy similar to that observed for 5-fluorouracil. Interestingly, number of vessels were significantly decreased in the treated groups. Moreover, CPBMF-223 significantly reduced the migration of cell line HCT-116. In the Ames assay and in an acute oral toxicity test, the molecule did not alter any evaluated parameter. Using the zebrafish toxicity model, cardiac and locomotor parameters were slightly changed. Regarding the pharmacokinetics profile, CPBMF-223 showed clearance of 9.42 L/h/kg after intravenous administration, oral bioavailability of 13.5%, and a half-life of 0.75 h. Our findings shed new light on the role of hTP in colorectal cancer induced by HCT-116 cell in mice, pointing out CPBMF-223 as, hopefully, a promising drug candidate.

Gamma-Decanolactone Alters the Expression of GluN2B, A1 Receptors, and COX-2 and Reduces DNA Damage in the PTZ-Induced Seizure Model After Subchronic Treatment in Mice.

Gamma-decanolactone (GD) has been shown to reduce epileptic behavior in different models, inflammatory decreasing, oxidative stress, and genotoxic parameters. This study assessed the GD effect on the pentylenetetrazole (PTZ) model after acute and subchronic treatment. We evaluated the expression of the inflammatory marker cyclooxygenase-2 (COX-2), GluN2B, a subunit of the NMDA glutamate receptor, adenosine A1 receptor, and GD genotoxicity and mutagenicity. Male and female mice were treated with GD (300 mg/kg) for 12 days. On the tenth day, they were tested in the Hot Plate test. On the thirteenth day, all animals received PTZ (90 mg/kg), and epileptic behavior PTZ-induced was observed for 30 min. Pregabalin (PGB) (30 mg/kg) was used as a positive control. Samples of the hippocampus and blood were collected for Western Blotting analyses and Comet Assay and bone marrow to the Micronucleus test. Only the acute treatment of GD reduced the seizure occurrence and increased the latency to the first stage 3 seizures. Males treated with GD for 12 days demonstrated a significant increase in the expression of the GluN2B receptor and a decrease in the COX-2 expression. Acute and subchronic treatment with GD and PGB reduced the DNA damage produced by PTZ in males and females. There is no increase in the micronucleus frequency in bone marrow after subchronic treatment. This study suggests that GD, after 12 days, could not reduce PTZ-induced seizures, but it has been shown to protect against DNA damage, reduce COX-2 and increase GluN2B expression.

Genotoxic effect induced by dried nicotiana tabacum leaves from tobacco barns (kiln-houses) in chinese hamster lung fibroblast cells (V79).

Nicotiana tabacum is the most cultivated tobacco species in the state of Rio Grande do Sul, Brazil. Workers who handle the plant are exposed to the leaf components during the harvesting process and when separating and classifying the dried leaves. In addition to nicotine, after the drying process, other components may be found including tobacco-specific nitrosamines, polycyclic aromatic hydrocarbons, as well as pesticides residues. The objective of this study was to examine the genotoxicity attributed to the aqueous extract of dried tobacco leaves obtained from tobacco barns using Chinese hamster lung fibroblast cells (V79) as a model system by employing alkaline comet assay, micronucleus (MN) and Ames test. MTT assay was used to assess cytotoxicity and establish concentrations for this study. Data demonstrated cell viability > 85% for concentrations of 0.625-5 mg/ml while the comet assay indicated a significant increase in DNA damage at all concentrations tested. A significant elevation of MN and nuclear buds (NBUD) was found for 5 mg/ml compared to control and other dry tobacco leaves concentrations (0.625-2.5 mg/ml). Mutagenicity was not found using the Salmonella/Microsome test (TA98, TA100, and TA102 strains) with and without metabolic activation. The concentration of inorganic elements was determined employing the PIXE technique, and 13 inorganic elements were detected. Using CG/MS nicotine amounts present were 1.56 mg/g dry tobacco leaf powder. Due to the observed genotoxicity in V79 cells, more investigations are needed to protect the health of tobacco workers exposed daily to this complex mixture of toxic substances present in dry tobacco leaves.

Evaluation of toxicity and mutagenicity of a synthetic effluent containing azo dye after Advanced Oxidation Process treatment.

Approximately 20% industrial water pollution comes from textile dyeing process, with Azo dyes being a major problem in this scenario and requiring new forms of efficient treatment. Effluent treatments using the Advanced Oxidation Processes (AOP) are justified by the potential of application in the dyed effluent treatments once they can change the Azo dye chemical structure. Thus, this study aimed to evaluate the toxicity and mutagenic capacity of a synthetic effluent containing Amido Black 10B (AB10B) azo dye before treatment with AOP, named Gross Synthetic Effluent (GSE), and after the AOP, named Treated Synthetic Effluent (TSE). Daphnia magna and Allium cepa tests were used to evaluate acute toxicity effects and chromosomal mutagenesis, respectively. The Salmonella/microsome assay was performed to evaluate gene mutations. In silico assays were also performed aiming to identify the mutagenic and carcinogenic potential of the degradation byproducts of AB10B. There was 100% immobility to D. magna after 24 h and 48 h of treatments with TSE, showing EC50 values around 5%, whereas GSE did not show acute toxicity. However, GSE induced chromosomal mutations in A. cepa test. Both GSE and TSE were not able to induce gene mutations in S. typhimurium strains. These effects can be associated with two byproducts generated with the cleavage of the azo bonds of AB10B, 4-nitroaniline and -2-7-triamino-8-hydroxy-3-6-naphthalinedisulfate (TAHNDS). In conclusion, AOP is an efficient method to reduce the mutagenicity of synthetic effluent containing AB10B and additional methods should be applied aiming to reduce the toxicity.

In vivo and in vitro toxicological evaluations of aqueous extract from Cecropia pachystachya leaves.

CECROPIA PACHYSTACHYA: leaves are popularly used to treat asthma and diabetes. Despite the widespread consumption of this plant, there are few scientific studies regarding its toxicological potential. In order to conduct a thorough study concerning the potential adverse effects, the aim of this study was to assess acute and subacute toxicity tests of crude aqueous extract from C. pachystachya leaves (CAE-Cp) using in vivomodel, as well as in vitro cytotoxicity, genotoxicity and antioxidant activity. In addition, genotoxicity, and cytotoxicity of chlorogenic acid (CGA) and cytotoxicity of isoorientin (ISOO) were also evaluated. The antioxidant activity was verified by DPPH, cytotoxicity using sulforhodamine B (SRB) assay and genotoxicity by comet assay on V79 cells. The phytochemical analysis of CAE-Cp detected flavonoids and tannins, CGA and ISOO as the major compounds utilizing HPLC. The total flavonoid content (6.52 mg/g EQ) and antioxidant activity (EC50 = 62.15 µg/ml) of CAE-Cp were determined. In vitro evaluations with CAE-Cp showed genotoxic effects at 0.31 to 2.5 mg/ml and an expressive cytotoxicity on HT-29 (IC50 = 4.43 µg/ml) cells. CGA was genotoxic against V79 cells at 0.07 mg/ml and cytotoxic against to HT-29 (IC50 = 71.70 µg/ml), OVCAR-3 (IC50 = 80.07 µg/ml), MCF-7 (IC50 = 45.58 µg/ml) and, NCI-H460 (IC50 = 71.89 µg/ml) cancer cell lines. Wistar rats treated with a single dose (2,000 mg/kg) CAE-Cp decreased hemoglobin levels after 14 days, although no significant toxicity was observed in animals after 28 days. In view of the in vitro cytotoxicity and genotoxicity detected, further studies are necessary to establish the safe use of CAE-Cp.

Recombinant peptide derived from the venom the Phoneutria nigriventer spider relieves nociception by nerve deafferentation.

The avulsion of nerve roots of the brachial plexus that is commonly seen in motorcycle accidents is a type of neuropathy due to deafferentation. This type of pain is clinically challenging since therapeutical protocols fail or have severe side effects. Thus, it is proposed to evaluate the antinociceptive activity of the recombinant CTK 01512-2 peptide that is derived from the venom of the Phoneutria nigriventer spider, as a future new therapeutical option. The neuropathic pain was surgically induced by avulsion of the upper brachial plexus trunk in groups of male Wistar rats and after 17 days, they were treated intrathecally with morphine, ziconotide, and CTK 01512-2. Behavioral tests were performed to evaluate mechanical and thermal hyperalgesia, cold allodynia, the functional activity of the front paw, and exploratory locomotion after the treatments. The peripheral blood samples were collected 6 h after the treatments and a comet assay was performed. The spinal cord was removed for the lipoperoxidation dosing of the membranes. The cerebrospinal fluid was analyzed for the dosage of glutamate. The recombinant peptide showed an antinociceptive effect when compared to the other drugs, without affecting the locomotor activity of the animals. Mechanical and thermal hyperalgesia, as well as cold allodynia, were reduced in the first hours of treatment. The levels of glutamate and the damage by membrane lipoperoxidation were shown to be improved, and genotoxicity was not demonstrated. In a scenario of therapeutical failures in the treatment of this type of pain, CTK 01512-2 was shown as a new effective alternative protocol. However, further testing is required to determine pharmacokinetics.

Evaluation of DNA damage in spinal cord and mutagenic effect of a Phα1ß recombinant toxin with analgesic properties from the Phoneutria nigriventer spider.

Phα1ß peptide isolated from the venom of the Phoneutria nigriventer spider has shown higher analgesic action in pre-clinical studies than ω-conotoxin MVIIA peptide used to treat severe chronic pain. In view of the great potential for the development of a new Phα1ß-based drug, a Phα1ß recombinant form (CTK 01512-2) has been studied for efficacy and safety. The aim of this study was to evaluate cytotoxic, genotoxic and mutagenic effects of a Phα1ß recombinant form and compare it with native Phα1ß and ω-conotoxin MVIIA. Cytotoxicity was evaluated using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) colourimetric assay in L929 mouse fibroblast cells (0.5-10.0 µmol/L). Genotoxic and mutagenic activities were analysed using the alkaline comet assay in peripheral blood and spinal cord, and the micronucleus test in bone marrow from Wistar rats treated by intrathecal injection of CTK 01512-2 (200, 500 and 1000 pmol/site), native Phα1ß (500 pmol/site) and ω-conotoxin MVIIA (200 pmol/site). CTK 01512-2 decreased the cell viability of the L929, showing IC50 of 3.3 ± 0.1 µmol/L, while the Phα1ß and ω-conotoxin MVIIA did not show cytotoxicity (IC50  > 5.0 µmol/L). Native and recombinant Phα1ß forms induced DNA damage in the spinal cord, but not in peripheral blood. CTK 01512-2 at 1000 pmol/site increased the micronucleus frequency suggesting mutagenic effects. In conclusion, the recombinant form has cytotoxic, genotoxic and mutagenic effects, evidenced in doses five times above the therapeutic dose.

Amido Black 10B a widely used azo dye causes DNA damage in pro- and eukaryotic indicator cells.

Acid Black 10B (AB10B) is widely used for the production of textiles, leather and prints. It is a representative of azo dyes and it is well documented that some of these compounds are mutagenic per se, and that cleavage products (in particular aromatic amines) may cause damage of the genetic material and cancer. Since no toxicological data on AB10B have been published, we evaluated its mutagenic activity in Salmonella/microsome assays and studied its acute toxic and genotoxic properties in a human derived liver cell line (HepG2) which retained the activities of drug metabolizing enzymes. The compound did not cause cytotoxicity (MTT assay), but clear genotoxic effects were detected in pro- and eukaryotic indicator cells. Dose dependent induction of his+ revertants was seen in strain TA98 which detects frameshift mutations without metabolic activation; a more pronounced effect was seen in its derivative YG1024 which overexpresses N-acetyltransferase. Induction of single/double strand breaks by Comet assay was detected with concentrations > 0.125 mg/mL in liver derived cells; as well as increased rates for micronucleus (reflecting structural and numeric chromosomal aberrations) and nuclear buds which are a consequence of gene amplifications were seen with a higher dose (2.0 mg/mL) (p < 0.05; Tukey's test). The mutational pattern which was observed in the bacterial tests indicates that the cleavage product p-nitroaniline may cause the genotoxic effects of the dye. Our findings indicate that exposure of humans and the release of the compound into the environment may lead to adverse effects due to its DNA damaging activity.

Biotoxicological Analyses of Trimeroside from Baccharis trimera Using a Battery of In Vitro Test Systems.

The use in folk medicine of Baccharis trimera and recent studies on DNA damage by oxidative stress mechanisms have motivated this study. We investigated the biotoxicological effects of trimeroside from this plant. Aqueous extract from aerial parts of B. trimera was fractioned by flash chromatography for further isolation by thin-layer chromatography. The novel nor-monoterpene glycoside, trimeroside, and three flavonoids, cirsimaritin, luteolin and quercetin, were isolated. The genotoxic and mutagenic potential of trimeroside was determined by Salmonella/microsome (TA98 and TA100), comet assay, and cytokinesis-block micronucleus cytome assay (CBMN-cyt) in HepG2 cells. We also screened trimeroside into different human tumoral cell lines by sulforhodamine B (SRB) assay. Mutagenicity was detected in TA100 strain with metabolic activation. Genotoxic effects were not observed in HepG2 by comet assay. However, a decrease in the nuclear index division in the 2.0 mg·mL-1 concentration and an increase of nucleoplasmic bridges in the 1.5 mg·mL-1 concentration were detected by CBMN-cyt assay indicating cytotoxic and mutagenic effects. In SRB assay, trimeroside showed weak antiproliferative activity against the cell lines.

Persistent Increased Frequency of Genomic Instability in Women Diagnosed with Breast Cancer: Before, during, and after Treatments.

This study aimed to evaluate DNA damage in patients with breast cancer before treatment (background) and after chemotherapy (QT) and radiotherapy (RT) treatment using the Comet assay in peripheral blood and the micronucleus test in buccal cells. We also evaluated repair of DNA damage after the end of RT, as well as the response of patient's cells before treatment with an oxidizing agent (H2O2; challenge assay). Fifty women with a mammographic diagnosis negative for cancer (control group) and 100 women with a diagnosis of breast cancer (followed up during the treatment) were involved in this study. The significant DNA damage was observed by increasing in the index and frequency of damage along with the increasing of the frequency of micronuclei in peripheral blood and cells of the buccal mucosa, respectively. Despite the variability of the responses of breast cancer patients, the individuals presented lesions on the DNA, detected by the Comet assay and micronucleus Test, from the diagnosis until the end of the oncological treatment and were more susceptible to oxidative stress. We can conclude that the damages were due to clastogenic and/or aneugenic effects related to the neoplasia itself and that they increased, especially after RT.