In Vivo Antistress Effects of Synthetic Flavonoids in Mice: Behavioral and Biochemical Approach.

Natural flavonoids, in addition to some of their synthetic derivatives, are recognized for their remarkable medicinal properties. The present study was designed to investigate the in vitro antioxidant and in vivo antistress effect of synthetic flavonoids (flavones and flavonols) in mice, where stress was induced by injecting acetic acid and physically through swimming immobilization. Among the synthesized flavones (F1-F6) and flavonols (OF1-OF6), the mono para substituted methoxy containing F3 and OF3 exhibited maximum scavenging potential against DPPH (2,2-diphenyl-1-picrylhydrazyl) with IC50 of 31.46 ± 1.46 µg/mL and 25.54 ± 1.21 µg/mL, respectively. Minimum antioxidant potential was observed for F6 and OF6 with IC50 values of 174.24 ± 2.71 µg/mL and 122.33 ± 1.98 µg/mL, respectively, in comparison with tocopherol. The ABTS scavenging activity of all the synthesized flavones and flavonols were significantly higher than observed with DPPH assay, indicating their potency as good antioxidants and the effectiveness of ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) assay in evaluating antioxidant potentials of chemical substances. The flavonoids-treated animals showed a significant (* p < 0.05, ** p < 0.01 and *** p < 0.001, n = 8) reduction in the number of writhes and an increase in swimming endurance time. Stressful conditions changed plasma glucose, cholesterol and triglyceride levels, which were used as markers when evaluating stress in animal models. The level of these markers was nearly brought to normal when pre-treated with flavones and flavonols (10 mg/kg) for fifteen days in experimental animals. These compounds also considerably reduced the levels of lipid peroxidation (TBARS: Thiobarbituric acid reactive substances), which was significant (* p < 0.05, ** p < 0.01 and *** p < 0.001, n = 8) compared to the control group. A significant rise in the level of catalase and SOD (super oxide dismutase) was also observed in the treated groups. Diazepam (2 mg/kg) was used as the standard drug. Additionally, the flavonoids markedly altered the weight of the adrenal glands, spleen and brain in stress-induced mice. The findings of the study suggest that these flavonoids could be used as a remedy for stress and are capable of ameliorating diverse physiological and biochemical alterations associated with stressful conditions. However, further experiments are needed to confirm the observed potentials in other animal models, especially in those with a closer resemblance to humans. Toxicological evaluations are also equally important.

Effects of Artemisia macrocephala Jacquem on Memory Deficits and Brain Oxidative Stress in Streptozotocin-Induced Diabetic Mice.

Different species of Artemisia have been reported to have therapeutic potential in treating various health disorders, including diabetes and memory dysfunction. The present study was planned to evaluate the effects of Artemisia macrocephala Jacquem crude extract and its subfractions as antiamnesic agents in streptozotocin-induced (STZ) diabetic mice. The in vivo behavioral studies were performed using the Y Maze test and novel object recognition test (NORT) test at doses of 100 and 200 mg/kg of crude extract and 75 and 150 mg/kg of fractions. The in vitro and ex vivo anticholinesterase activities, along with biochemical parameters (superoxide dismutase, catalase, glutathione and lipid peroxidation) in the brain, were evaluated. Blood glucose levels were monitored with a glucometer; crude extract and fractions reduced the glucose level considerably, with some differences in the extent of their efficacies. The crude extract and fractions demonstrated significant inhibitory activity against cholinesterases (AChE and BuChE) in vitro. Crude, chloroform and ethyl acetate extract were found to be more potent than the other fractions, with IC50 of Crd-Am = 116.36 ± 1.48 and 240.52 ± 1.35 µg/mL, Chl-Am = 52.68 ± 1.09 and 57.45 ± 1.39 µg/mL and Et-Am = 75.19 ± 1.02 and 116.58 ± 1.09 µg/mL, respectively. Oxidative stress biomarkers like superoxide dismutase, catalase and glutathione levels were elevated, whereas MDA levels were reduced by crude extract and all fractions with little difference in their respective values. The Y-maze test and novel object recognition test demonstrated declines in memory impairment in groups (n = 6) treated with crude extract and fractions as compared to STZ diabetic (amnesic) group. The most active fraction, Chl-Am, was also subjected to isolation of bioactive compounds; three compounds were obtained in pure state and designated as AB-I, AB-II and AB-III. Overall, the results of the study showed that Artemisia macrocephala Jacquem enhanced the memory impairment associated with diabetes, elevated acetylcholine levels and ameliorated oxidative stress. Further studies are needed to explore the beneficial role of the secondary metabolites isolated in the present study as memory enhancers. Toxicological aspects of the extracts are also important and need to be evaluated in other animal models.

Neuroprotective Potential of Synthetic Mono-Carbonyl Curcumin Analogs Assessed by Molecular Docking Studies.

Cognitive decline in dementia is associated with deficiency of the cholinergic system. In this study, five mono-carbonyl curcumin analogs were synthesized, and on the basis of their promising in vitro anticholinesterase activities, they were further investigated for in vivo neuroprotective and memory enhancing effects in scopolamine-induced amnesia using elevated plus maze (EPM) and novel object recognition (NOR) behavioral mice models. The effects of the synthesized compounds on the cholinergic system involvement in the brain hippocampus and their binding mode in the active site of cholinesterases were also determined. Compound h2 (p < 0.001) and h3 (p < 0.001) significantly inhibited the cholinesterases and reversed the effects of scopolamine by significantly reducing TLT (p < 0.001) in EPM, while (p < 0.001) increased the time exploring the novel object. The % discrimination index (DI) was significantly increased (p < 0.001) in the novel object recognition test. The mechanism of cholinesterase inhibition was further validated through molecular docking study using MOE software. The results obtained from the in vitro, in vivo and ex vivo studies showed that the synthesized curcumin analogs exhibited significantly higher memory-enhancing potential, and h3 could be an effective neuroprotective agent. However, more study is suggested to explore its exact mechanism of action.

Activity guided isolation and mechanistic approach towards analgesic potential of Chenopodium mediated through opioidergic pathway.

The current study is focused towards screening for its phytochemicals, phenolic and flavonoid contents of different species of Chenopodium. The plants were also screened for corroborating the traditional use of medicinal plants locally used for pain by determining the extract and their fractions for the in-vivo analgesic activity by using the modern scientific system. Among chloroform fractions, a high level of total phenolic contents was found in chloroform fraction of Chenopodium ambrosioides (ChAm-Chf) with 57.12±1.02 followed by Chenopodium botrys (ChBt-Chf) with 56.79±0.71. High content of flavonoids was found in chloroform fraction of Chenopodium botrys (ChBt-Chf) extract with 78.35±0.84 followed by Chenopodium ambrosioides (ChAm-Chf) with 75.20±0.81. The crude extract Chenopodium album, Chenopodium botrys and Chenopodium ambrosioides (ChAl-Crd, ChBt-Crd and ChAm-Crd) at 100 and 200 mg/kg, chloroform and ethylacetate fractions (ChAl-Chf, ChBt-Chf, ChAm-Chf, ChAl-Et, ChBt-Et and ChAm-Et) at 75 mg/kg caused significant inhibition (P<0.05, P<0.01, P<0.001, n=8) of the analgesic response induced by acetic acid, formalin and hotplate method. Mechanistically, the naloxone overturns completely the analgesic effects of beta-sitosterol (SN2) while partial reversal was observed by ursolic acid (SN1) indicating other possible mechanisms in association with opioid receptors.

GC/MS analysis, anti-leishmanial and relaxant activity of essential oil of Chenopodium ambrosioides (L.) from Malakand region.

Chenopodium ambrosioides is abundantly available in Malakand region. As constituents and concentrations of essential oils vary based on its geographical location, we carried our current study to extract and evaluate its possible relaxant activity in rabbits' jejunum and anti-leishmanial activity against promastigotes of Leishmania tropica. The essential oil was obtained from aerial fresh parts through steam distillation followed by GC/MS analysis. Antispasmodic activity was performed on spontaneous and KCl induced contractions. Curves for calcium concentration response (CCRCs) were prepared with and without different concentrations of essential oils and verapamil - a standard calcium channel blocker as per our reported procedures. GC/MS analysis indicated that the essential oil contains 4-carene (56.59%) and o-cymene (41.46%), the two most abundant compounds previously reported from this species. The LD50 value for acute toxicity is 279.66±2.2mg/kg. The essential oil have significant antileishmanial activity with LC50 of Log10 (1.83±0.0026) ×10-6mg/ml, potent relaxant activity on rabbits' jejunal preparations with respective EC50 = 1.46±0.15mg/ml for spontaneous activity. For KCl (80mM) induced contractions, EC50=0.26±0.02mg/ml. In CCRCs, the oil produced a right shift as exhibited by verapamil. More, its relaxant activity, which is mediated through calcium channel blocking mechanism, proves a rationale for its traditional use in gut spasm.

Synthetic flavonols and flavones: A future perspective as anticancer agents.

A series of flavonoid derivatives, flavones (F1-F3) and flavonols (OF1-OF3) were synthesized. Their structures were confirmed through various spectroscopic techniques and elemental analysis. These were then tested for cytotoxic activity against mouse fibroblast (NIH 3T3), human endothelial cervical (HeLa) and breast (MCF7) cell lines in vitro by MTT assay. The flavonol series showed prominent potentials than the flavones. The compound OF2 in flavonols exhibited greater potentials MCF7 cell with IC50 value of 0.96µM and OF3 has 1.04µM. In contrast, the OF3 exhibited higher activity against HeLa cell with IC50 value of 0.51µM and OF2 has 1.06µM. The compounds OF2 and OF3 exhibited activity against mouse fibroblast (NIH 3T3) cell with IC50 values 2.48 and 1.24µM. The OF1 was found to be moderate to inactive against all cells. Cytotoxic screening of the tested flavones, F1 to F3 were also active against all cells but the activity was less in comparison to flavonol series of compounds suggestion the possible involvement of hydroxyl (OH) at position 3 in case of flavonols. These results indicated a cheering scaffold that may lead to innovation of potent anti-breast cancer activity.

Nootropic effects of synthetic flavonoid derivatives on scopolamine induced memory impairment in mice via cholinesterase inhibition and antioxidant system.

The synthesized flavonoid derivatives (flavonols and flavones) were subjected for in-vitro anticholinesterase evaluation followed by assessment of in-vivo memory enhancing effects using animal models. The ex-vivo analysis of brain was carried out and portions were subjected foe estimation of biochemical parameters that includes AChE, ACh, SOD and CAT level. Among tested flavonoids, the para substituted chloro containing flavonol (OF2) and flavone (F2) revealed a considerable in-vitro AChE and BuChE % inhibition with an IC50 values. It was observed from the in-vivo results that OF1-OF3 at 12.5 mg/kg b.w has significance over F1-F3 in ameliorating the memory in scopolamine induced amnesic mice in passive avoidance step through and novel object recognitions test. Scopolamine elevated significantly the AChE level, decreased the contents of ACh, SOD and CAT in the brain in amnesic model. The flavonoid derivatives showed significant effects on these changes by decreasing the ex-vivo AChE contents, enhancing the level of ACh, SOD and CAT suggesting their possible role as cholinesterase and antioxidant. These findings suggest that synthetic flavonols and flavones may serve as potential candidates for developing safer and effective nootropic agents.

Hepaotoprotective and nephroprotective activities of Pistacia integerrima fruit extract in paracetamol intoxicated male rabbits with effect on blood cells count.

The beneficial effects of Pistacia integerrima (PI) fruit methanol extract on some liver and kidney related parameters and blood cells count of paracetamol (PCM) intoxicated male rabbits were studied. Paracetamol intoxication caused remarkable increase in the serum ALT, AST and ALP levels. The PCM intoxicated rabbits that received PI extract orally at doses of 200 mg and 400 mg/kg b.w. /oral/day for 16 days showed significant reduction in serum ALT, AST and ALP levels (P<0.05). Liver microsections from PCM intoxicated rabbits treated with PI fruit methanol extract showed improvement in the liver histoarchitecture. The urine output of PCM intoxicated control rabbits group was significantly lower (P<0.05). The PCM intoxicated rabbits that received PI extract showed significant increase in urine output (P<0.05). The PCM intoxicated rabbits treated with PI extract also showed significant reduction in the levels of serum urea and creatinine (P<0.05). The renal creatinine clearance of PCM rabbits treated with PI extract improved significantly (P<0.05). Microsections of kidneys from PCM intoxicated rabbits treated with PI fruit methanol extract showed improvement in renal histoarchitecture. During this study, PI extract caused no improvement in the RBC count of PCM intoxicated rabbits. However, the extract caused significant increase in WBC and platelets count (P < 0.05) of PCM intoxicated rabbits. From the findings of the present research, it was concluded that oral administration of P. integerrima fruit methanol extract is beneficial for the liver and kidney related biochemical parameters and blood cells count of paracetamol intoxicated male rabbits.

Antidiabetic potential of flavonoids from Artemisia macrocephalla Jaquem in streptozotocin-induced diabetic rats: Pharmacological and biochemical approach.

Plants belongs to Asteraceae family are reported to be rich in major phytochemical including flavonoids and are documented to acquire antidiabetic response. Antidiabetic effects of salvigenin, eupatilin and cirsilineol were screened on in-vitro enzyme inhibition and in-vivo streptozotocin animal models. Administration of salvigenin, eupatilin and cirsilineol (7.5 and 15mg/kg) produced antidiabteic responses in streptozotocin model for diabetes. All natural flavonoids reduces the blood glucose level to a significant level (*P<0.05, **P<0.01, ***P<0.001, n=8) but promising results were observed in eupatilin at dose of 7.5mk/kg (364.12±4.3 to 128.41±4.2mg/dL, n=8) and at dose of 7.5mk/kg 363.65±4.8 to 126.14±5.1mg/dL, n=8). Administration of salvigenin, eupatilin and cirsilineol (7.5 and 15mg/kg) for 28 days showed a substantial fall (*P<0.05, **P<0.01, ***P<0.001, n=8) in total cholesterol, LDL and triglcerides (TGs) in comparison to diabetic model. The isolated flavonoids reduced considerably the serum ALP, SGPT and SGOT in rats intoxicated with streptozotocin. The results indicate that the flavonoids may be useful in the development of new antidiabetic drugs.

Scientific investigation of crude alkaloids from medicinal plants for the management of pain.

BACKGROUND: Tissue damage is associated with pain, which is an alarming sign. Aspirin and morphine have been widely used in recent decades for management of pain. Medicinal herbs have been in use for treatment of different diseases for centuries. Many of these herbs possess analgesic activity with relatively less incidences of adverse effects. The strong positive correlation of alkaloids in medicinal plants for analgesic activity persuades an intention to determine possible analgesic activity of total alkaloids extracted from the selected medicinal plants using animal models to answer its possible mechanisms. METHODS: Crude alkaloids from selected medicinal plants (Woodfordia fruticosa, Adhatoda vasica, Chenopodium ambrosioides, Vitex negundo, Peganum harmala and Broussonetia papyrifera) were extracted as per reported literature. The test crude alkaloids were screened foracute toxicity study. Writhings induced by acetic acid, tail immersion method and formalin-induced nociception assay procedures were used for possible analgesic effects of the crude alkaloids. RESULTS: Crude alkaloids were safe up to dose of 1250 mg/kg body weight in mice. The alkaloids significantly reduced the abdominal constrictions, and increased the time for paw licking response in both phases with a significant raise in latency time in nociception models (P ≤ 0.05). Moreover, the antinociceptive response was significantly attenuated by pretreatment with naloxone suggesting involvement of the opioid receptors for possible antinociceptive action. CONCLUSIONS: Crude alkaloids of Woodfordia fruticosa and Peganum harmala showed prominent analgesic potentials through inhibition of peripheral as well as central nervous system mechanisms. Further work is required for isolation of the pharmacologically active constituents.

Design and synthesis of 2-amino-4,6-diarylpyrimidine derivatives as potent α-glucosidase and α-amylase inhibitors: structure-activity relationship, in vitro, QSAR, molecular docking, MD simulations and drug-likeness studies.

In the present study, a series of 2-amino-4,6-diarylpyrimidine derivatives was designed, synthesized, characterized and evaluated for their in vitro α-glucosidase and α-amylase enzyme inhibition assays. The outcomes proved that this class of compounds exhibit considerable inhibitory activity against both enzymes. Among the target compounds, compounds 4p and 6p demonstrated the most potent dual inhibition with IC50 = 0.087 ± 0.01 µM for α-glucosidase; 0.189 ± 0.02 µM for α-amylase and IC50 = 0.095 ± 0.03 µM for α-glucosidase; 0.214 ± 0.03 µM for α-amylase, respectively as compared to the standard rutin (IC50 = 0.192 ± 0.02 µM for α-glucosidase and 0.224 ± 0.02 µM for α-amylase). Remarkably, the enzyme inhibition results indicate that test compounds have stronger inhibitory effect on the target enzymes than the positive control, with a significantly lower IC50 value. Moreover, these series of compounds were found to inhibit α-glucosidase activity in a reversible mixed-type manner with IC50 between 0.087 ± 0.01 µM to 1.952 ± 0.26 µM. Furthermore, molecular docking studies were performed to affirm the binding interactions of this scaffold to the active sites of α-glucosidase and α-amylase enzymes. The quantitative structure-activity relationship (QSAR) investigations showed a strong association between 1p-15p structures and their inhibitory actions (IC50) with a correlation value (R2) of 0.999916. Finally, molecular dynamic (MD) simulations were carried out to assess the dynamic behavior, stability of the protein-ligand complex, and binding affinity of the most active inhibitor 4p. The experimental and theoretical results therefore exposed a very good compatibility. Additionally, the drug-likeness assay revealed that some compounds exhibit a linear association with Lipinski's rule of five, indicating good drug-likeness and bioactivity scores for pharmacological targets.Communicated by Ramaswamy H. Sarma.

Beneficial Effects of Natural Alkaloids from Berberis glaucocarpa as Antidiabetic Agents: An In Vitro, In Silico, and In Vivo Approach.

Diabetes, also known as diabetes mellitus (DM), is a metabolic disorder characterized by an abnormal rise in blood sugar (glucose) levels brought on by a complete or partial lack of insulin secretion along with corresponding changes in the metabolism of lipids, proteins, and carbohydrates. It has been reported that medicinal plants play a pivotal role in the treatment of various ailments such as diabetes mellitus, dyslipidemia, and hypertension. The current study involved exploring the acute toxicity and in vivo antidiabetic activity of berberine (WA1), palmatine (WA2), and 8-trichloromethyl dihydroberberine (WA3) previously isolated from Berberis glaucocarpa Stapf using a streptozotocin (STZ)-induced diabetic rat model. Body weight and blood glucose level were assessed on a day interval for 4 weeks. Biochemical parameters, antioxidant enzymes, and oxidative stress markers were also determined. In an acute toxicity profile, the WA1, WA2, and WA3 were determined to be nontoxic up to 500 mg/kg (b.w). After the second and third weeks of treatment (14 and 21 days), the blood glucose levels in the WA1-, WA2-, and WA3-treated groups were significantly lower than those in the diabetic control group (476.81 ± 8.65 mg/dL, n = 8, P < 0.001). On the 21st day, there was a decrease in the blood glucose level and the results obtained were 176.33 ± 4.69, 197.21 ± 4.80, and 161.99 ± 4.75 mg/dL (n = 8, P < 0.001) for WA1, WA2, and WA3 at 12 mg/kg, respectively, as opposed to the diabetic control group (482.87 ± 7.11 mg/dL, n = 8, P < 0.001). Upon comparison with the diabetic group at the end of the study (28 days), a substantial drop in the glucose level of WA3 at 12 mg/kg (110.56 ± 4.11 mg/dL, n = 8, P < 0.001) was observed that was almost near the values of the normal control group. The treated groups (WA1, WA2, and WA3) treated with the samples displayed a significant decline in the levels of HbA1c. Treatment of the samples dramatically lowered the lipid level profile. In groups treated with samples, plasma levels of triglycerides, total cholesterol, and LDL were significantly lowered [F (5, 42) = 100.6, n = 8, P < 0.001]; these levels were also significantly decreased [F (5, 42) = 129.6 and 91.17, n = 8, P < 0.001]. In contrast to the diabetes group, all treated groups had significantly higher HDL levels [F (5, 42) = 15.46, n = 8, P < 0.001]. As a result, hypolipidemic activity was anticipated in the samples. In addition to that, the activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) was considerably elevated in the groups treated with the sample compared to the diabetic control group (n = 8, P < 0.001).

Acute toxicity, brine shrimp cytotoxicity, anthelmintic and relaxant potentials of fruits of Rubus fruticosus Agg.

BACKGROUND: Rubus fruticosus is used in tribal medicine as anthelmintic and an antispasmodic. In the current work, we investigated the anthelmintic and antispasmodic activities of crude methanol extract of fruits of R. fruticosus on scientific grounds. Acute toxicity and brine shrimp cytotoxicity activity of the extract were also performed. METHODS: Acute toxicity study of crude methanol extract of R. fruticosus was performed on mice. In vitro Brine shrimp cytotoxicity assay was performed on shrimps of Artemia salina. In vitro Anthelmintic activity was tested against Raillietina spiralis and Ascaridia galli. Relaxant activities were tested on spontaneous rabbits' jejunal preparations. Calcium chloride curves were constructed to elucidate possible mode of action of the extract. RESULTS: LD 50 of the extract for acute toxicity studies was 887.75 ± 9.22 mg/ml. While CC 50 of the extract for Brine shrimps cytotoxicity assay was 13.28 ± 2.47 µg/ml. Test samples of crude methanolic extract of R. fruticosus (Rf.Cr) at concentration 20 mg/ml showed excellent anthelmintic activity against Raillietina spiralis. Anthelmintic activity was 1.37 times of albendazole against the Raillietina spiralis at concentration 40 mg/ml. At higher concentration (40 mg/ml), Rf.Cr has 89. 83% parasiticidal activity. The mean EC50 relaxation activity for spontaneous and KCl-induced contractions was 7.96 ± 0.1 and 6.45 ± 0.29 mg/ml, respectively. EC 50 (Log[Ca++]M) for control calcium chloride curves was -1.75 ± 0.01 vs. EC 50 -1.78 ± 0.06 in the presence of 3.0 mg/ml of Rf.Cr. Similarly, EC 50(Log[Ca++]M) in the absence and presence of verapamil (0.1 µM) were -2.46 ± 0.01 and -1.72 ± 0.02, respectively. CONCLUSIONS: The anthelmintic and relaxant activities explained traditional uses of R. fruticosus on scientific grounds. Relaxant activity follows the inhibition of voltage gated channels. Although the plant extract has cytotoxic effects, yet it is evident from acute toxicity study that it is safe in concentration 100 mg/kg. Further work is required to isolate pharmacologically active compounds.

Anthelmintic and relaxant activities of Verbascum Thapsus Mullein.

BACKGROUND: Verbascum thapsus is used in tribal medicine as an antispasmodic, anti-tubercular agent and wormicide. In this study, we investigated the antispasmodic and anthelmintic activities of crude aqueous methanolic extract of the plant. METHODS: V. thapsus extracts were tested against roundworms (Ascaridia galli) and tapeworms (Raillietina spiralis). Each species of worm was placed into a negative control group, an albendazole treatment group, or a V. thapsus treatment group, and the time taken for paralysis and death was determined. In addition, relaxation activity tests were performed on sections of rabbit's jejunum. Plant extracts were tested on KCl-induced contractions and the relaxation activities were quantified against atropine. V. thapsus calcium chloride curves were constructed to investigate the mode of action of the plant extracts. RESULTS: We detected flavonoids, saponins, tannins, terpenoids, glycosides, carbohydrates, proteins, fats and fixed oils in V. thapsus. For both species of worm, paralysis occurred fastest at the highest concentration of extract. The relative index values for paralysis in A. galli were 4.58, 3.41 and 2.08, at concentrations of 10, 20 and 40 mg/ml of plant extract, respectively. The relative index for death in A. galli suggested that V. thapsus extract is wormicidal at high concentration. Similarly, the relative indexes for paralysis and death in R. spiralis suggested that the extract is a more potent wormicidal agent than albendazole. The mean EC(50) relaxation activity values for spontaneous and KCl induced contractions were 7.5 ± 1.4 mg/ml (6.57-8.01, n = 6) and 7.9 ± 0.41 mg/ml (7.44-8.46, n = 6), respectively. The relaxation activity of the extract was 11.42 ± 2, 17.0 ± 3, 28.5 ± 4, and 128.0 ± 7% of the maximum observed for atropine at corresponding concentrations. The calcium chloride curves showed that V. thapsus extracts (3 mg/ml), had a mean EC(50) (log molar [calcium]) value of -1.9 ± 0.06 (-1.87 - -1.98, n = 6) vs. control EC(50) = -2.5 ± 0.12 (-2.37 - -2.56, n = 6), whereas the verapamil (0.1 µM) EC(50) was -1.7 ± 0.1 (-1.6 - -1.8, n = 6) vs. control EC(50) = -2.4 ± 0.09 (-2.3 - -2.47, n = 5). CONCLUSIONS: Our results suggest that V. thapsus, which is currently used by some tribes in the Malakand region of Pakistan, has anthelmintic and antispasmodic value.

Flavonoid Derivatives as Potential Cholinesterase Inhibitors in Scopolamine-Induced Amnesic Mice: An In Vitro, In Vivo and Integrated Computational Approach.

Flavonoids are one of the most exciting types of phenolic compounds with a wide range of bioactive benefits. A series of flavone derivatives (F1-F5) were previously synthesized from substituted O-hydroxy acetophenone and substituted chloro-benzaldehydes. The titled compounds F1-F5 in the present study were evaluated for their anticholinesterase potential (against AChE and BuChE). The obtained results were then validated through a molecular docking approach. Compound F5 was found to be the most potent inhibitor of AChE (IC50 = 98.42 ± 0.97 µg/mL) followed by compound F4, whereas compound F2 was found to be the most promising inhibitor of BuChE (IC50 = 105.20 ± 1.43 µg/mL) among the tested compounds. The molecular docking analysis revealed a similar trend in the binding affinity of compounds with the targeted enzymes and found them to be capable of forming highly stable complexes with both receptors. The selected compounds were further subjected to in vivo assessment of cognitive function in a scopolamine-induced amnesic animal model, in which almost all compounds F1-F5 significantly attenuated the amnesic effects as evaluated through Y-Maze Paradigm and novel object discrimination (NOD) tasks, findings that were further supported by ex vivo experimental results. Among (F1-F5), F5 showed significant anti-amnesic effects in scopolamine-induced amnesic models and ameliorated the memory loss in behavioral model studies as compared to counterparts. In ex vivo study, noteworthy protection from oxidative stress in the brains of scopolamine-induced amnesic mice was also recorded for F5. These findings also confirmed that there were no significant differences among the in vivo and ex vivo results after administration of F1-F5 (7.5 or 15 mg/kg) or donepezil (2 mg/kg). These synthesized flavonoids could serve as potential candidates for new neuroprotective and nootropic drugs. However, further studies are needed to validate their observed potential in other animal models as well.

Acute toxicity, brine shrimp cytotoxicity and relaxant activity of fruits of callistemon citrinus curtis.

BACKGROUND: Callistemon citrinus Curtis belongs to family Myrtaceae that has a great medicinal importance. In our previous work, fruits of Callistemon citrinus were reported to have relaxant (antispasmodic) activity. The current work describes the screening of fractions of the crude methanol extract for tracing spasmolytic constituents so that it shall help us for isolation of bioactive compounds. Acute toxicity and brine shrimp cytotoxicity of crude methanol extract are also performed to standardize it. METHODS: The crude methanol extract was obtained by maceration with distilled water (500 ml) three times and fractionated successively with n-hexane, chloroform, ethyl acetate and n-butanol (300 ml of each solvent). Phytochemical analysis for crude methanol extract was performed. Acute toxicity studies were performed in mice. Brine shrimp cytotoxicity studies were performed to determine its cytotoxicity and standardize it. In other series of experiments, rabbits' jejunum preparations were used in screening for possible relaxant activities of various fractions. They were applied in concentrations of 0.01, 0.03, 0.1, 0.3, 1.0, 3.0, 5.0 and 10.0 mg/ml on spontaneous rabbits' jejunum preparations. In similar fashion, fractions were also tested on KCl (80 mM) -induced contractions. Calcium chloride curves were constructed in K-rich Tyrode's solution. The effects of various fractions were tested on calcium chloride curves at concentrations 1.0, 3.0, 5.0 and 10.0 mg/ml. Curves of verapamil used as reference drug at concentration 0.1 µM and 0.3 µM were also constructed. The curves were compared with their respective controls for possible right shift. RESULTS: Methanol extract tested strongly positive for saponins and tannins. However, it tested mild positive for presence of proteins, amino acids, carbohydrates and phenolic compounds. LD(50) value for crude methanol extract is 476.25 ± 10.3 (470-481, n = 4) mg/ml. Similarly, EC(50) value for brine shrimp cytotoxicity is 65.5 ± 7.28 (60.8- 69.4, n = 4) mg/ml. All the fractions relaxed the spontaneous and KCl-induced contractions. EC(50) values (mg/ml) for effects of ethyl acetate fraction on spontaneous and KCl induced contractions are 2.62 ± 0.78 (2.15-3.0, n = 4) and 3.72 ± 0.86 (3.38-4.28, n = 4) respectively. Respective EC(50) values (mg/ml) for n-butanol fraction are 3.59 ± 0.2(3.07-3.9, n = 4) for spontaneous, and 5.57 ± 0.2 (5.07-6.11, n = 4) for KCl- induced contractions. EC(50) value for control calcium chloride curve (without extract) is -2.73 ± 0.19 (-2.6 - -2.81, n = 4) while EC(50) for curves treated with 5.0 mg/ml of chloroform is -2.22 ± 0.02 (-2.16 - -2.3, n = 4). EC(50) value for ethyl acetate treated (1.0 mg/ml) tissues is -1.95 ± 0.10 (-1.88 - -2.0, n = 4) vs. control EC(50) = -2.71 ± 0.08 (-2.66 - -2.76, n = 4). All the fractions, except n-hexane, showed a right shift like that of verapamil (EC(50) = -1.72 ± 0.15 (-1.62 - -1.8, n = 4) vs. Control EC(50) = -2.41 ± 0.06 (-2.38 - - 2.44, n = 4), a standard drug that blocks voltage operated calcium channels. CONCLUSION: Relaxant constituents were more concentrated in ethylacetate fraction followed by chloroform, n -butanol and aqueous fractions that warrant for its isolation. The crude methanol extract is safe at concentration 250 mg/ml or below and results of brine shrimp cytotoxicity assay imply the plant specie may be a source of cytotoxic agents.

Cytotoxic and anthelmintic potential of crude saponins isolated from Achillea Wilhelmsii C. Koch and Teucrium Stocksianum boiss.

BACKGROUND: Saponins isolated from plant sources have a number of traditional and industrial applications. Saponins have pharmacological effects like anti-inflammatory, molluscicidal, antimicrobial, antispasmodic, antidiabetic, anticancer, anticonvulsant, anthelmintic, antitussive and cytotoxic activities. The current work describes the anthelmintic and cytotoxic activities of crude saponins of Achillea Wilhelmsii and Teucrium Stocksianum as these plants are rich with saponins. METHODS: Brine shrimp cytotoxic activity of crude saponins was determined by Meyer et al. (1982) at test concentrations of 1000 µg/ml, 100 µg/ml, 10 µg/ml, 7.5 µg/ml, 5.0 µg/ml, 2.5 µg/ml and 1.25 µg/ml. Percentage mortality of test concentrations was determined. Similarly, in vitro anthelmintic activity was determined against roundworms, tapeworms and earthworms. Albendazole and piperazine citrate at concentration 10 mg/ml were used as standard anthelmintic drugs. RESULTS: Crude saponins of Achillea wilhelmsii (CSA) and Teucrium stocksianum (CST) had, respectively, cytotoxic activity with LC50 values 2.3±0.16 and 5.23±0. 34 µg/ml. For in vitro anthelmintic activity, time for paralysis and death of parasites (parasiticidal activity) was noted. At concentration 40 mg/ml, crude saponins of Achillea wilhelmsii are 1.96 and 2.12 times more potent than albendazole against Pheretima posthuma and Raillietina spiralis, respectively. Similarly, at concentration 40 mg/ml, crude saponins of Teucrium stocksianum (CST) has 1.89, 1.96 and 1.37 times more parasiticidal activity than albendazole against Pheretima posthuma, Raillietina spiralis and Ascardia galli, respectively. CONCLUSION: Crude saponins of Achillea wilhelmsii and Teucrium stocksianum have cytotoxic and anthelmintic activity. The crude saponins may be excellent sources of cytotoxic and anthelmintic constituents that warrant its isolation and purification for new drug development.