The interplay of solvent-drug-protein interactions during albumin nanoparticles formulations for temozolomide delivery to brain cancer cells.

OBJECTIVES: Temozolomide (TMZ), the first line for glioma therapy, suffers from stability at physiological pH. TMZ was selected as a challenging model drug for loading into human serum albumin nanoparticles (HSA NPs). Our aim is to optimise the conditions for TMZ loading into HSA NPs while ensuring TMZ stability. METHODS: Blank and TMZ-HSA NPs were fabricated using the de-solvation technique and the effect of different formulation parameters was evaluated. KEY FINDINGS: For blank NPs, crosslinking time had no significant effect on NPs' size while acetone produced significantly smaller particles than ethanol. Upon drug loading, though TMZ was stable in acetone and ethanol as single agents yet, ethanol-based NPs showed misleadingly high EE% due to drug instability in ethanol formulations as evident by the UV spectrum.The optimum conditions for drug-loaded particles were: 10 mg/ml HSA, 4 mg TMZ using acetone, yielded NPs with 145 nm in diameter, ξ of -16.98 mV and 0.16% DL. The selected formula reduced the cell viabilities of GL261 glioblastoma cells and BL6 glioblastoma stem cells to 61.9% and 38.3%, respectively. CONCLUSIONS: Our results corroborated that careful manipulation of TMZ formulation processing parameters is crucial for encapsulating such chemically unstable dug while simultaneously ensuring its chemical stability.

RESET-PKD: a pilot trial on short-term ketogenic interventions in autosomal dominant polycystic kidney disease.

BACKGROUND: Ketogenic dietary interventions (KDI) have been shown to be effective in animal models of polycystic kidney disease (PKD), but data from clinical trials are lacking. METHODS: Ten autosomal dominant PKD (ADPKD) patients with rapid disease progression were enrolled at visit V1 and initially maintained a carbohydrate-rich diet. At V2, patients entered one of the two KDI arms: a 3-day water fast (WF) or a 14-day ketogenic diet (KD). At V3, they resumed their normal diet for 3-6 weeks until V4. At each visit, magnetic resonance imaging kidney and liver volumetry was performed. Ketone bodies were evaluated to assess metabolic efficacy and questionnaires were used to determine feasibility. RESULTS: All participants [KD n = 5, WF n = 5; age 39.8 ± 11.6 years; estimated glomerular filtration rate 82 ± 23.5 mL/min/1.73 m2; total kidney volume (TKV) 2224 ± 1156 mL] were classified as Mayo Class 1C-1E. Acetone levels in breath and beta-hydroxybutyrate (BHB) blood levels increased in both study arms (V1 to V2 average acetone: 2.7 ± 1.2 p.p.m., V2 to V3: 22.8 ± 11.9 p.p.m., P = .0006; V1 to V2 average BHB: 0.22 ± 0.08 mmol/L, V2 to V3: 1.88 ± 0.93 mmol/L, P = .0008). Nine of 10 patients reached a ketogenic state and 9/10 evaluated KDIs as feasible. TKV did not change during this trial. However, we found a significant impact on total liver volume (ΔTLV V2 to V3: -7.7%, P = .01), mediated by changes in its non-cystic fraction. CONCLUSIONS: RESET-PKD demonstrates that short-term KDIs potently induce ketogenesis and are feasible for ADPKD patients in daily life. While TLV quickly changed upon the onset of ketogenesis, changes in TKV may require longer-term interventions.

Mechanistic efficacy assessment of selected novel methanimine derivatives against vincristine induced Neuropathy: In-vivo, Ex-vivo and In-silico correlates.

Vincristine induced peripheral neuropathy (VIPN) is a serious untoward side effect suffered by cancer patients, which still lacks an adequate therapeutic approach. This study examined the alleviating potential of novel methanimine derivatives i.e. (E)-N-(4-nitrobenzylidene)-4-chloro-2-iodobenzamine (KB 9) and (E)-N-(2-methylbenzylidene)-4-chloro-2-iodobenzamine (KB 10) in VIPN. Vincristine was injected in BALB/c mice for 10 days to instigate nociceptive neuropathy. Dynamic and static allodynia, thermal (hot and cold) hyperalgesia were evaluated at 0, 5, 10 and 14 days using cotton brush, Von Frey filament application, hot plate test, acetone drop and cold water respectively. Tumour necrosis factor alpha (TNF-α), interleukin-1ß (IL-1ß), lipid peroxide (LPO), glutathione-S-transferase (GST), catalase (CAT), superoxide dismutase (SOD) and reactive oxygen species (ROS) assays were performed to assess the efficacy of KB9 and KB10 against neuroinflammation and oxidative stress utilizing ELISA, immunohistochemistry and western blot analysis in brain and sciatic nerve tissues. Computational studies were executed to determine the stable binding conformation of both compounds with respect to COX-2 and NF-κB. Interestingly, both compounds substantially reduced protein expression related to neuroinflammation, oxidative stress (LPO, GST, SOD, CAT) and pain (NF-κB, COX-2, IL-1ß and TNF-α). This molecular analysis suggested that the neuroprotective effect of KB9 and KB10 was mediated via regulation of inflammatory signaling pathways. Overall, this study demonstrated that KB9 and KB10 ameliorated vincristine induced neuropathy, through anti-inflammatory, anti-nociceptive and antioxidant mechanisms.

Treadmill workouts alleviate neuropathic allodynia and scratching behavior in rats following thoracotomy.

BACKGROUND: The aim of the experiment was to investigate the effects of treadmill exercise on postthoracotomy pain and the expression of spinal pro-inflammatory and anti-inflammatory cytokines. METHODS: Animals were randomly distributed into four groups: (a) sham surgery, (b) rats following 60 min thoracotomy and rib retraction (thoracotomy), (c) thoracotomy rats received treadmill training (thoracotomy+treadmill), and (d) sham surgery rats received treadmill training (sham surgery+treadmill). Treadmill workouts were started on postoperative day 10 (POD10) and lasted for 6 weeks (5 days per week). Rats were examined for cold allodynia using acetone and mechanical allodynia using von Frey hairs (in grams) at the surgical site. Spinal pro-inflammatory and anti-inflammatory cytokines were analyzed on PODs 28 and 49. RESULTS: Both thoracotomy and thoracotomy+treadmill groups exhibited a decrease in mechanical force thresholds (g) and an increase in scratches per min on POD10. Mechanical hypersensitivity and incremental scratches lasted from POD14 and POD49 in the thoracotomy group. Although force thresholds and scratches remained not return to baseline, incremental force thresholds (p < 0.001) and diminutive scratches (p < 0.001) occurred after 6-week treadmill workouts. The rise in spinal interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) concentrations or the decline in spinal IL-10 concentration in thoracotomy+treadmill rats was less (p < 0.05) than thoracotomy rats without exercise. CONCLUSIONS: Mechanical allodynia using von Frey filament testing and cold allodynia by acetone testing were improved in thoracotomy rats after treadmill workouts.. Treadmill exercise restrained excess pro-inflammatory cytokine expression but increased anti-inflammatory cytokine level in a rib retraction model.

Potential effect of Turbinaria decurrens acetone extract on the biochemical and histological parameters of alloxan-induced diabetic rats.

Upon Seeking natural and safe alternatives for synthetic medicines to treat many chronic diseases, seaweeds have offered a promising resource to produce numerous bioactive secondary metabolites. Through in vivo investigations, Turbinaria decurrens acetone extract (AE) revealed its antidiabetic activity against alloxan-induced diabetic rats. Treatment of rats with T. decurrens AE at 300 and 150 mg/Kg doses revealed antihyperglycemic activity by reducing the elevated blood glucose level. A remarkable decrease in the liver, kidney functions, and hyperlipidemia related to diabetes were also detected. Administration of the same extract also showed a recovery in body weight loss, total protein, albumin, and haemoglobin levels compared with untreated diabetic rats. Furthermore, treatment of rats with the same extract improved liver and pancreas histopathological disorders related to diabetes. These effects may be attributed to the presence of bioactive phytochemicals and antioxidant components in T. decurrens AE mainly cyclotrisiloxane, hexamethyl, and cyclic diterpene 3,7,11,15-tetramethyl-2-hexadecen-1-ol (phytol alcohol). Besides, other valuable secondary metabolites, as phenols, flavonoids, alkaloids, terpenoids, steroid and glycosides, which were documented and published by the same authors in a previous study. The obtained results in the present study recommended using T. decurrens AE in developing medicinal preparations for treatment of diabetes and its related symptoms.

Modular Acid-Activatable Acetone-Based Ketal-Linked Nanomedicine by Dexamethasone Prodrugs for Enhanced Anti-Rheumatoid Arthritis with Low Side Effects.

Given the physically encapsulated payloads with drug burst release and/or low drug loading, it is critical to initiate an innovative prodrug strategy to optimize the design of modular nanomedicines. Here, we designed modular pH-sensitive acetone-based ketal-linked prodrugs of dexamethasone (AKP-dexs) and formulated them as nanoparticles. We comprehensively studied the relationships between AKP-dex structure and properties, and we selected two types of AKP-dex-loaded nanoparticles for in vivo studies on the basis of their size, drug loading, and colloidal stability. In a collagen-induced arthritis rat model, these AKP-dex-loaded nanoparticles showed higher accumulation in inflamed joints and better therapeutic efficacy than free dexamethasone phosphate with less-severe side effects. AKP-dex-loaded nanoparticles may be useful for treating other inflammatory diseases and thus have great translational potential. Our findings represent an important step toward the development of practical applications for acetone-based ketal-linked prodrugs and are useful in the design of modular nanomedicines.

Acetone clearance of mesocolic or mesorectal fat increases lymph node yield and may improve detection of high-risk Stage II colorectal cancer patients.

AIM: Lymph node (LN) status is key to determining the need for adjuvant therapy in colorectal cancer (CRC) and for disease which has progressed to Stage II (T3-T4, N0, M0). A yield of fewer than 12 LNs is considered a risk factor similar to high-grade histology and vascular, lymphatic and perineural invasion. The aim of this retrospective study was to investigate the effect of acetone fat clearance of the mesocolon or mesorectum on LN yield and the identification of patients with high-risk Stage II CRC. METHOD: After conventional LN retrieval, fatty tissue derived from the mesocolon or mesorectum of 80 CRC specimens was incubated in acetone for 24 h. A second dissection was then performed by a trained technician. The total number of LNs as well as tumour involvement (LNpositive and LNnegative) were assessed at each stage. In addition, LN morphology was assessed and clinicopathological data were extracted from existing pathology reports. RESULTS: Eighty CRC specimens were available for study. 1548 (94%) LN were negative and 96 (6%) were positive. The median (range) LN yield per specimen was 12 (3-41) LN increasing to 18 (4-48) LN after fat clearance (P < 0.001). After fat clearance, 534 additional LNs were identified in 75 (94%) of the specimens, and all but 10 were negative. The pN stage did not change in six patients who were found to be LN positive after fat clearance. However, the number of high-risk Stage II CRC patients decreased from 11 to 7. Although important for these patients, this downstaging did not reach statistical significance (P = 0.125). CONCLUSION: Acetone clearance of mesocolic or mesorectal fat increases median LN yield and may in a larger study decrease the number of patients classified as having high-risk Stage II CRC.

Antioxidant potential of Xylopia aethiopica fruit acetone fraction in a type 2 diabetes model of rats.

The fruit decoction of Xylopia aethiopica (Dunal) A. Rich. is widely used for the treatment of diseases associated with oxidative stress such as diabetes, particularly in Africa. The present study was aimed to investigate the effects of X. aethiopica fruit acetone (XAFA) fraction in ameliorating oxidative stress in a type 2 diabetes (T2D) model of rats. The crude X. aethiopica fruit ethanolic extract was fractionated using solvents with increasing polarity and acetone fraction showed significantly (p<0.05) higher in vitro antioxidant potentials which were measured by (1,1-diphenyl-2-picrylhydrazyl radical (DPPH), hydroxyl radical (HRS) and nitric oxide (NO) assays compared to other fractions. It was then subjected to in vivo antioxidant study in a T2D rat model. Acetone fraction depicted potent in vitro antioxidant actions (IC50: DPPH: 19.82±0.73µg/mL; HRS: 25.34±6.19µg/mL; NO: 14.45±2.44µg/mL) compared to other fractions. Additionally, a significant (p<0.05) and dose-dependent improvement on the in vivo antioxidant status was observed in the animals in diabetic treated groups (DXAL, DXAH) compared to the diabetic control (DBC) group. The results of our study suggest that XAFA possesses potent antioxidant potential and could be used to ameliorate oxidative stress associated metabolic complications such as T2D.

Effect of prolonged air drying on the bond strength of adhesive systems to dentin.

This in vitro study evaluated the effect of air-drying time on degree of solvent evaporation (DE), dentin microtensile bond strength (µTBS), and degree of conversion (DC) of 5 adhesive systems: Adper Single Bond 2, XP Bond, Prime & Bond 2.1, OptiBond Solo, and Adper Easy One. For DE testing, 20 µL of each material was submitted to measurements in a digital balance after an air stream of 3, 5, 10, 20, 30, or 60 seconds; the weight loss was computed and converted to a percentage (DE). For µTBS testing, 50 sound human molars were divided into groups (n = 5). The 5 adhesive systems were applied either in accordance with manufacturers' instructions for solvent drying time (control) or with a prolonged drying time (20-30 seconds). After composite resin was built up on the hybridized surfaces, the teeth were stored for 24 hours and then sectioned to obtain beams that were loaded until fracture. For DC testing, specimens of each adhesive and air-drying condition (n = 3) were evaluated by means of attenuated total reflectance Fourier transform infrared spectroscopy. Data were submitted to 2-way analysis of variance, t test, and Spearman test for correlation analysis. Prolonged air drying resulted in significantly greater DE than did the time suggested by the manufacturers. The adhesives XP Bond and Adper Easy One showed significantly greater µTBS with prolonged air drying. The DC was not affected by air-drying time. No statistically significant correlation was found between DC and µTBS values. Depending on the material, bond strength can be improved by prolonged air-drying times.

Caesappin A and B, two novel protosappanins from Caesalpinia sappan L.

Two novel protosappanins, named Caesappin A (1) and B (2), along with three known protosappanins were isolated from Caesalpinia sappan L. Caesappin A is a new type protosappanin with a seven-membered ring fusing an acetal-type section. Compound 4 was isolated from the genus Caesalpinia for the first time. The structures were elucidated on the basis of spectral analysis and the absolute configuration was determined by the ECD experiment coupled with calculated ECD spectra. Their cytotoxic activities were evaluated using MTT assay.

A focused review of the role of ketone bodies in health and disease.

Ketone bodies are produced in the liver and are utilized in other tissues in the body as an energy source when hypoglycemia occurs in the body. There are three ketone bodies: acetoacetate, beta hydroxy butyrate, and acetone. Ketone bodies are usually present in the blood, and their level increases during fasting and starvation. They are also found in the blood of neonates and pregnant women. In diabetic ketoacidosis, high levels of ketone bodies are produced in response to low insulin levels and high levels of counter-regulatory hormones.

Acetone extract from Streptoverticillium sp., a bacterium isolated from Brazilian Cerrado soil, induces anti-inflammatory activity in mice.

The Streptoverticillium sp. Z1 is an actinomycete isolated from the soil under Cerrado vegetation, the extract of this strain was investigated in nociceptive and inflammatory models. The Streptoverticillium extract (ExS) 50 and 100 mg/kg (s.c.) produced a significant inhibition of acetic acid-induced abdominal writhings thereby demonstrating an anti-nociceptive effect. In the tail flick test the ExS (s.c.) was inactive. This result implited that ExS does not contain opioid-like compounds with central analgesic properties. In the inflammatory models, ExS 100 and 200 mg/kg (s.c.) were able to inhibit the croton oil-induced ear edema and, ExS 200 and 500 mg/kg (s.c.) inhibited the leukocyte migration on the carrageenan-induced peritonitis. The phospholipase A2 enzymatic assay showed that the anti-inflammatory activity of ExS was not due to direct effect on phospholipase A2 activity. These data suggest that Streptoverticillium sp. produces metabolites with anti-inflammatory effect and that these metabolites are unable to directly inhibit phospholipase A2 enzyme.

Hepatoprotective effect of acetone semicarbazone on Ehrlich ascites carcinoma induced carcinogenesis in experimental mice.

OBJECTIVE: To determine the hepatoprotective effect of acetone semicarbazone (ASC) in vivo in normal and Ehrlich ascites carcinoma (EAC) bearing male Swiss albino mice. METHODS: Drug-induced changes in biochemical and behavioral parameters at dose of 2.0 mg/kg body weight for 14 d and nullifying the toxicity induced by EAC cells were studied. The histopathology studies of the protective effects of ASC on vital organs were also assessed. RESULTS: The administration of ASC made insignificant changes in body weight and behavioral (salivation, diarrhea, muscular numbness) changes during treatment period due to minor toxicity were minimized after the treatment in normal mice. The biochemical parameters, including serum glutamate pyruvate transaminase, glutamate oxaloactate transaminase, alkaline phosphatase, serum glucose, cholesterol, urea, triglyceride and billirubin changed modestly in normal mice receiving ASC. Though the treatment continued, these values gradually decreased to normal level after the treatment. In EAC bearing mice, the toxic effects due to EAC cells in all cases were nullified by treatment with the ASC. Significant abnormalities were not detected in histology of the various organs of the normal mice treated with ASC. CONCLUSIONS: ASC can, therefore, be considered safe in formulating novel anticancer drug, as it exhibits strong protective effect against EAC cell bearing mice.

Chemical composition and biological evaluation of Physalis peruviana root as hepato-renal protective agent.

This study was designed to investigate the potential of Physalis peruviana root as a functional food with hepato-renal protective effects against fibrosis. The chemical composition of the plant root suggested the presence of alkaloids, withanolides and flavonoids. Five compounds were isolated and their structures elucidated by different spectral analysis techniques. One compound was isolated from the roots: cuscohygrine. The biological evaluation was conducted on different animal groups; control rats, control treated with ethanolic root extract, CCl(4) group, CCl(4) treated with root extract, and CCl(4) treated with silymarin as a standard herbal drug. The evaluation used the oxidative stress markers malondialdehyde (MDA), superoxide dismutase (SOD), and nitric oxide (NO). The liver function indices; aspartate and alanine aminotransferases (AST & ALT), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), bilirubin, and total hepatic protein were also estimated. Kidney disorder biomarkers; creatinine, urea, and serum protein were also evaluated. The results suggested safe administration, and improvement of all the investigated parameters. The liver and kidney histopathological analysis confirmed the results. In conclusion, P. peruviana succeeded in protecting the liver and kidney against fibrosis. Further studies are needed to discern their pharmacological applications and clinical uses.

Dual-cured etch-and-rinse adhesive systems increase the bond durability of direct coronal dentin restorations.

This study aimed to evaluate the bond durability of dentin restorations bonded with light- or dual-cured etch-and-rinse adhesive systems. A three-step adhesive system (Scotchbond Multipurpose Plus), an acetone-based two-step adhesive system (Prime & Bond 2.1), and an ethanol-based two-step adhesive system (Excite) were tested. Both the light- and the dual-cured versions were evaluated. High C-factor dentin cavities were prepared on 120 bovine incisors, which were then restored with resin composite (n=10). The samples were stored in water for 24 hours, and half of them were subjected to additional degradation with 10% NaOCl for five hours. The push-out bond strength test was performed in a universal testing machine until failure. Failure modes were evaluated by scanning electron microscopy. Data were analyzed by three-way analysis of variance and Tukey tests (p<0.05). The dual-cured adhesive system presented a higher immediate bond strength and durability than those that were light cured. The three-step adhesive system produced the highest values, whereas the acetone-based adhesive system produced the lowest result. Therefore, the use of dual-cured etch-and-rinse adhesive systems can induce increased bond durability to direct coronal dentin restorations.

Neuron-restrictive silencer factor is not required for the antiepileptic effect of the ketogenic diet.

PURPOSE: The ketogenic diet (KD) has been used as an effective antiepileptic treatment for nearly a century. Inhibition of glycolysis and increased levels of ketone bodies are both known to contribute to the antiepileptic effects of the KD. Neuron-restrictive silencer factor (NRSF), also known as RE-1 silencing transcription factor (REST), is implicated in the antiepileptic effects of the glycolytic inhibitor 2-deoxy-d-glucose (2DG). Glycolytic inhibition is a common feature of the KD and 2DG treatment, leading to the hypothesis that NRSF might also be involved in the antiepileptic effect of the KD. To test this hypothesis, the present study was designed to investigate the role of NRSF in the antiepileptic effect of 2DG, the KD, and acetone in vivo. METHODS: Kindling was used as a model to test the antiepileptic effects of 2DG, the KD, and acetone on control and NRSF conditional knockout mice (NRSF-cKO; from the intercross of CamKIIα-iCre and NRSF exon 2 floxed mice). After recovery from electrode implantation, adult mice were stimulated twice a day at afterdischarge threshold (ADT) current intensity. In the 2DG- (500 mg/kg) and acetone- (10 mmol/kg) treated groups, drugs were injected intraperitoneally 20 min before each stimulus. In the 2DG group, mice were pretreated with intraperitoneal injections for 3 days in addition to the injections administered before the regular kindling stimulation. In the KD group, mice were fed the KD instead of a control diet until the end of stimulations. KEY FINDINGS: Compared with control mice, the antiepileptic effect of 2DG was abolished in NRSF-cKO mice, indicating that NRSF is required for the antiepileptic effect of 2DG. In the KD-fed group, kindling development was retarded in both control and NRSF-cKO mice. In the acetone-treated group, inhibition of kindling-induced epileptogenesis was observed in both control and NRSF-cKO mice, similar to the action of the KD. SIGNIFICANCE: These findings imply that NRSF repression complex is not essential for the antiepileptic effect of the ketogenic diet.

Anticonvulsant effects of methyl ethyl ketone and diethyl ketone in several types of mouse seizure models.

The anticonvulsant effects of acetone have been reported in various animal models of epilepsy. We recently demonstrated that other ketone bodies, methyl ethyl ketone (MEK) and diethyl ketone (DEK), suppressed status epilepticus that was induced by lithium-pilocarpine in rat. In the present study, the anticonvulsant effects of MEK and DEK were evaluated by using four different types of mouse seizure models, which were induced by pentylenetetrazole, kainic acid, methyl-6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate (DMCM), and electroshock. The effects of clonazepam, a typical anticonvulsant, and acetone were also evaluated and compared with MEK and DEK. In this study, MEK (5 and 10 mmol/kg, i.p.) and DEK (2.5 and 5 mmol/kg, i.p.) produced anticonvulsant activity against all types of seizure models. Furthermore, MEK and DEK showed almost the same potencies against four different seizure models used, while clonazepam showed significant higher ED(50) values against kainic acid-induced and electroshock-induced seizure models as compared with the pentylenetetrazole- or DMCM-induced seizure model. In each study, the highest doses of clonazepam (1 or 3mg/kg) did not show clear anticonvulsant effects against the kainic acid- or electroshock-induced seizures. In conclusion, MEK and DEK showed broad-spectra anticonvulsant effects in both chemically- and electroshock-induced experimental seizure models.

Reactivation of brain acetylcholinesterase by monoisonitrosoacetone increases the therapeutic efficacy against nerve agents in guinea pigs.

Current oxime therapies do not readily cross the blood-brain barrier to reactivate organophosphorus nerve agent-inhibited cholinesterase (ChE) within the CNS. We investigated the ability of monoisonitrosoacetone (MINA), a tertiary oxime, to reactivate ChE inhibited by the nerve agent sarin (GB), cyclosarin (GF), or VX, in peripheral tissues and brain of guinea pigs and determined whether reactivation in the CNS will enhance protection against the lethal effects of these three agents. In the reactivation experiment, animals were pretreated with atropine methylnitrate (1.0mg/kg, i.m.) 15 min prior to subcutaneous (s.c.) challenge with 1.0 x LD(50) of GB, GF, or VX. Fifteen minutes later animals were treated intramuscularly (i.m.) with MINA (ranging from 22.1 to 139.3mg/kg) or 2-PAM (25.0mg/kg). At 60 min after nerve agent, CNS (brainstem, cerebellum, cortex, hippocampus, midbrain, spinal cord, and striatum) and peripheral (blood, diaphragm, heart, and skeletal muscle) tissues were collected for ChE analysis. MINA reactivated nerve agent-inhibited ChE in the CNS and peripheral tissues in a dose-dependent manner in the following order of potency: GB>GF>VX. In a survival experiment, animals were injected i.m. with atropine sulfate (0.5mg/kg), 2-PAM (25.0mg/kg), or MINA (35.0, 60.0, or 100.0mg/kg) alone or in combination 1 min after challenge with varying s.c. doses of GB, GF, or VX to determine the level of protection. The rank order of MINA's efficacy in guinea pigs against nerve agent lethality was the same as for reactivation of inhibited ChE in the CNS. These data show that MINA is capable of reactivating nerve agent-inhibited ChE and that the extent of ChE reactivation within the CNS strongly relates to its therapeutic efficacy.

Anticonvulsant activity of DNS II fraction in the acute seizure models.

AIM OF THE STUDY: Delphinium nordhagenii belongs to family Ranunculaceae, it is widely found in tropical areas of Pakistan. Other species of Delphinium are reported as anticonvulsant and are traditionally used in the treatment of epilepsy. Delphinium nordhagenii is used by local healer in Pakistan but never used for scientific investigation as anticonvulsant. Thus, Delphinium nordhagenii was subjected to bioassay-guided fractionation and the most active fraction, i.e. DNS II acetone was chosen for further testing in the acute seizure models of epilepsy to study the antiepileptic potential in male mice. MATERIALS AND METHODS: Different doses (60, 65 and 70mg/kg, i.p.) of DNS II acetone fraction of Delphinium nordhagenii was administered 30min prior the chemoconvulsant's injection in the male mice. Convulsive doses of chemoconvulsants (pentylenetetrazole 90mg/kg, s.c. and picrotoxin 3.15mg/kg, s.c.) were used. The mice were observed 45-90min for the presence of seizures. Moreover, four different doses of DNS II (60, 65, 70 and 100mg/kg, i.p.) were tested in the MES test. RESULTS: The DNS II acetone fraction of Delphinium nordhagenii has exhibited the anticonvulsant actions by preventing the seizures against PTZ- and picrotoxin-induced seizure as well as 100% seizure protection in MES test. The results are comparable with standard AEDs (diazepam 7.5mg/kg, i.p. and phenytoin 20mg/kg, i.p.). CONCLUSIONS: These findings suggest that the Delphinium nordhagenii possesses the anticonvulsant activity. Further analysis is needed to confirm the structure and target the extended activity profile.

Methyl ethyl ketone blocks status epilepticus induced by lithium-pilocarpine in rats.

BACKGROUND AND PURPOSE: A ketogenic diet has been used successfully to treat patients with intractable epilepsy, although the mechanism is unknown. Acetone has been shown to have an anticonvulsive effect in various animal models. The main purpose of this study was to determine whether other ketones, 2-butanone (methyl ethyl ketone: MEK) and 3-pentanone (diethyl ketone: DEK), also show anticonvulsive effects in lithium-pilocarpine (Li-pilocarpine)-induced status epilepticus (SE) in rats. EXPERIMENTAL APPROACH: Anticonvulsive effects of MEK and DEK in Li-pilocarpine SE rats were measured by behavioural scoring. Anti-seizure effects of MEK were also evaluated using electroencephalography (EEG). Neuroprotective effect of MEK was investigated by haematoxylin and eosin staining 4 weeks after the treatment with pilocarpine. KEY RESULTS: Acetone, MEK and DEK showed anticonvulsant effects in Li-pilocarpine-induced SE rats. Treatment with MEK twice (8 mmol.kg(-1) and 5 mmol.kg(-1)) almost completely blocked spontaneous recurrent cortical seizure EEG up to 4 weeks after the administration of pilocarpine. MEK also showed strong neuroprotective effects in Li-pilocarpine-treated rats 4 weeks following the administration of pilocarpine. Significant neural cell death occurred in the hippocampus of Li-pilocarpine SE rats, especially in the CA1 and CA3 subfields. In contrast, normal histological characteristics were observed in these regions in the MEK-pretreated rats. CONCLUSIONS AND IMPLICATIONS: Both MEK and DEK showed strong anticonvulsive effects in Li-pilocarpine-induced SE rats. They also inhibited continuous recurrent seizure and neural damage in hippocampal region for 4 weeks after the treatment with pilocarpine. These findings appear to be of value in the investigation of epilepsy.