Molecular mechanisms and signaling pathways of black cumin (Nigella sativa) and its active constituent, thymoquinone: a review.

BACKGROUND: Nigella sativa and its main bioactive ingredient, thymoquinone, exhibit various pharmacological activities, including neuroprotective, nephroprotective, cardioprotective, gastroprotective, hepatoprotective, and anti-cancer effects. Many studies have been conducted trying to elucidate the molecular signaling pathways that mediate these diverse pharmacological properties of N. sativa and thymoquinone. Accordingly, the goal of this review is to show the effects of N. sativa and thymoquinone on different cell signaling pathways. METHODS: The online databases Scopus, PubMed and Web of Science were searched to identify relevant articles using a list of related keywords such as Nigella sativa, black cumin, thymoquinone, black seed, signal transduction, cell signaling, antioxidant, Nrf2, NF-κB, PI3K/AKT, apoptosis, JAK/STAT, AMPK, MAPK, etc. Only articles published in the English language until May 2022 were included in the present review article. RESULTS: Studies indicate that N. sativa and thymoquinone improve antioxidant enzyme activities, effectively scavenges free radicals, and thus protect cells from oxidative stress. They can also regulate responses to oxidative stress and inflammation via Nrf2 and NF-κB pathways. N. sativa and thymoquinone can inhibit cancer cell proliferation through disruption of the PI3K/AKT pathway by upregulating phosphatase and tensin homolog. Thymoquinone can modulate reactive oxygen species levels in tumor cells, arrest the cell cycle in the G2/M phase as well as affect molecular targets including p53, STAT3 and trigger the mitochondrial apoptosis pathway. Thymoquinone, by adjusting AMPK, can regulate cellular metabolism and energy hemostasis. Finally, N. sativa and thymoquinone can elevate brain GABA content, and thus it may ameliorate epilepsy. CONCLUSIONS: Taken together, the improvement of antioxidant status and prevention of inflammatory process by modulating the Nrf2 and NF-κB signaling and inhibition of cancer cell proliferation through disruption of the PI3K/AKT pathway appear to be the main mechanisms involved in different pharmacological properties of N. sativa and thymoquinone.

Pharmacokinetic of berberine, the main constituent of Berberis vulgaris L.: A comprehensive review.

Barberry (Berberis vulgaris L.) is a medicinal plant and its main constituent is an isoquinoline alkaloid named berberine that has multiple pharmacological effects such as antioxidant, anti-microbial, antiinflammatory, anticancer, anti-diabetes, anti-dyslipidemia, and anti-obesity. However, it has restricted clinical uses due to its very poor solubility and bioavailability (less than 1%). It undergoes demethylenation, reduction, and cleavage of the dioxymethylene group in the first phase of metabolism. Its phase two reactions include glucuronidation, sulfation, and methylation. The liver is the main site for berberine distribution. Berberine could excrete in feces, urine, and bile. Fecal excretion of berberine (11-23%) is higher than urinary and biliary excretion routes. However, a major berberine metabolite is excreted in urine greater than in feces. Concomitant administration of berberine with other drugs such as metformin, cyclosporine A, digoxin, etc. may result in important interactions. Thus, in this review, we gathered and dissected any related animal and human research articles regarding the pharmacokinetic parameters of berberine including bioavailability, metabolism, distribution, excretion, and drug-drug interactions. Also, we discussed and gathered various animal and human studies regarding the developed products of berberine with better bioavailability and consequently, better therapeutic effects.

Cardioprotective effects of alpha-mangostin on doxorubicin-induced cardiotoxicity in rats.

The main adverse effect of doxorubicin is cardiotoxicity. Oxidative stress and apoptosis induction have been suggested as mechanisms involved in its cardiotoxicity. In this study, cardioprotective effects of alpha-mangostin against doxorubicin-induced cardiotoxicity have been investigated in rats. Forty-two rats were divided as follows: Control, doxorubicin (2 mg/kg every 48 hr), alpha-mangostin (200 mg/kg), alpha-mangostin (50, 100, 200 mg/kg) + doxorubicin (2 mg/kg every 48 hr), and vitamin E (200 IU/kg) + doxorubicin (2 mg/kg every 48 hr). Alpha-mangostin was administered by gavage for 19 days, while doxorubicin (12 days) and vitamin E (19 days) were injected intraperitoneally. Doxorubicin decreased heart rate, increased electrocardiogram signal components duration and reduced systolic and diastolic arterial blood pressure, and caused histological damage in the heart of rats. Doxorubicin decreased heart weight and heart/body weight ratio, as well as elevated creatine phosphokinase isoenzyme and lactate dehydrogenase. Doxorubicin increased malondialdehyde, inflammatory biomarkers, and caspases 3 and 9 and decreased reduced glutathione content in heart tissue but co-administration of alpha-mangostin (100 mg/kg) restored all doxorubicin toxic effects. Results show that alpha-mangostin has protective effects against doxorubicin-induced cardiotoxicity by antioxidant, antiinflammatory, and antiapoptotic effects that may ameliorate doxorubicin cardiotoxicity in human chemotherapy without reduction in its anticancer effect.

Quetiapine attenuates the acquisition of morphine-induced conditioned place preference and reduces ERK phosphorylation in the hippocampus and cerebral cortex.

Background: Quetiapine is an atypical antipsychotic that antagonizes dopamine and serotonin receptors. It has been suggested that quetiapine can be used to treat substance use disorders, including opioid use disorder. Opioids modulate dopaminergic functions associated with conditioned reinforcement and these effects can be measured via the conditioned place preference (CPP) paradigm. Opioids' unconditioned effects are regulated by several proteins, including extracellular signal-regulated kinase (ERK) and cAMP-responsive element-binding (CREB).Objective: To assess the effect of quetiapine on morphine-induced CPP and motor activity levels, and on the levels of ERK and CREB proteins in the hippocampus and cerebral cortex.Methods: 42 male rats were exposed to a CPP protocol, in which they underwent a conditioning paradigm with saline, quetiapine (40 mg/kg), morphine (10 mg/kg), morphine plus quetiapine (10, 20, or 40 mg/kg), or morphine plus memantine (7.5 mg/kg, a positive control drug) (n = 6 per group). The rats were tested for CPP and exploratory activity. Levels of ERK and CREB proteins in the hippocampus and cerebral cortex were also measured.Results: Quetiapine co-administered with morphine inhibited morphine-induced CPP [F (6, 70) = 11.67, p < .001] and morphine's effects on motor activity (p < .001). Morphine enhanced ERK phosphorylation in the hippocampus (p < .001) and cerebral cortex (p < .001), an effect inhibited by quetiapine.Conclusion: Quetiapine attenuates morphine-induced CPP and locomotion and these effects are associated with a reduction of ERK phosphorylation in the hippocampus and cerebral cortex. These results suggest that quetiapine should be further explored as a potential treatment for opioid use disorder.

Effects of Nigella sativa oil and thymoquinone against bisphenol A-induced metabolic disorder in rats.

The underlying mechanisms of bisphenol A (BPA)-induced metabolic disorder and the protective impact of Nigella sativa oil (NSO) and thymoquinone (TQ) against BPA-induced metabolic disorder were investigated. Rats were treated as follows: Control, BPA (10 mg/kg), TQ (2 mg/kg), NSO (84 µL/kg), BPA + TQ (0.5, 1, 2 mg/kg), and BPA + NSO (21, 42, 84 µL/kg). BPA was administered by gavage, while, TQ and NSO were injected intraperitoneally (daily, 54 days). The weight, blood pressure, serum parameters [glucose, lipid profile, hepatic enzymes, insulin, interlukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), leptin, adiponectin], malondialdehyde (MDA), glutathione (GSH) and insulin signaling pathways [insulin receptor substrate (p-IRS,IRS); kinase (p-Akt,Akt); glycogen synthase kinase (p-GS3K,GS3K)] were measured. BPA increased the blood pressure, MDA, lipid profile, hepatic enzymes, insulin, IL-6, TNF-α, and leptin, and decreased the GSH and phosphorylated forms of IRS, Akt, GS3K but did not alter weight, glucose, IRS, AKT, and GS3K in the liver. Administration of NSO or TQ with BPA reduced the blood pressure, liver level of MDA, lipid profile, hepatic enzymes, insulin, IL-6, TNF-α, leptin, and increased the liver level of GSH and p-IRS, p-AKT, p-GS3K. TQ and NSO are thought to be effective in controlling metabolic disorders induced by BPA.

Evaluation of green tea extract and epigallocatechin gallate effects on bisphenol A-induced vascular toxicity in isolated rat aorta and cytotoxicity in human umbilical vein endothelial cells.

This study was designed to assess bisphenol A (BPA)-induced vascular toxicity, the effectiveness of green tea extract and epigallocatechin gallate (EGCG) against BPA toxicity, and possible underlying mechanisms. In isolated rat aorta, contractile and relaxant responses as well as malondialdehyde levels were evaluated. Cell viability and effects on the protein levels of apoptotic (bax, bcl2, and caspase-3), autophagic (LC3), and cell adhesion molecules were calculated using the MTT method and western blotting in human umbilical vein endothelial cells (HUVECs). BPA increased aorta MDA levels (p < .0001) and decreased vascular responses to KCl [20 and 40 mM (p < .0001), 80 mM (p < .001)], phenylephrine [10-8 , 10-6 , and 10-5 M (p < .001), 10-7 and 10-4 M (p < .0001)], and acetylcholine [10-6 M (p < .01), 10-5 and 10-4 M (p < .0001)]. In HUVECs, BPA enhanced the levels of LC3A/B, bax/bcl2 ratio, cleaved caspase-3, and vascular cell adhesion molecule-1. Green tea extract, EGCG, and vitamin E co-treatment with BPA diminished the toxic effects of BPA. These findings provide evidence that green tea extract and EGCG possess beneficial effects in preventing BPA-induced vascular toxicity through increasing the antioxidant activities and the regulation of signaling pathways.

Berberine and barberry (Berberis vulgaris): A clinical review.

Barberry (Berberis vulgaris L.) has different medicinal applications in folk medicine of Iran. Berberine, an alkaloid constituent of this plant, is present in the roots, rhizomes, stem, and bark of B. vulgaris and many other plants. There have been many clinical trials conducted that suggested a wide range of therapeutic applications. Here, we investigated the clinical uses of berberine and B. vulgaris in the treatment of different diseases in humans. An extensive search in electronic databases (PubMed, Scopus, Embase, Web of Sciences and Science Direct) was used to identify the clinical trials on B. vulgaris and berberine. Lipid-lowering and insulin-resistance improving actions are the most studied properties of berberine in numerous randomized clinical trials. There are also clinical trials regarding cardiovascular, anticancer, gastrointestinal, CNS, endocrine, and so on. Berberine has very low toxicity in usual doses and reveals clinical benefits without major side effects. Only mild gastrointestinal reactions may occur in some patients. The purpose of this review is to provide a summary concerning the clinical trials conducted on berberine to improve the clinical application of this nutraceutical in different diseases. In this review article, we used 77 clinical studies on human subjects.

Vitis vinifera (grape) seed extract and resveratrol alleviate bisphenol-A-induced metabolic syndrome: Biochemical and molecular evidences.

The mechanisms of bisphenol-A (BPA)-induced metabolic syndrome as well as the protective role of grape seed extract (GSE) and resveratrol were investigated. Rats were treated with BPA (0 and 35 mg·kg-1 ·day-1 , gavage) plus resveratrol (25, 50, and 100 mg·kg-1 ·day-1 , i.p.) or GSE (3, 6, 12 mg·kg-1 ·day-1 , i.p.) or vitamin E (200 IU/kg/every other day, i.p.). After 2 months, mean systolic blood pressure, serum lipid profile, glycaemia, and fat index were examined. By enzyme-linked immunosorbent assay, the serum concentrations of insulin, leptin, adiponectin, and paraoxonase 1, and by real-time polymerase chain reaction as well as western blotting, key liver elements in cholesterol hemostasis (LDLR, CYP7A1, ABCG5 and 8) and insulin signaling (p-Akt/Akt and p-PI3K/PI3K) were measured. BPA increased mean systolic blood pressure, total cholesterol, and low-density lipoprotein cholesterol and reduced paraoxonase1 and the hepatic expression of both ABCG5 and ABCG8. It increased the body fat index, leptin, adiponectin, insulin, and glycaemia level and decreased the hepatic protein expression of p-Akt/Akt and p-PI3K/PI3k. GSE, resveratrol, or vitamin E coadministration along with BPA restored the detrimental effects of BPA in some levels. Herein, the predisposing effects of BPA-induced metabolic syndrome were restored by GSE and resveratrol, linked to the regulation of insulin signaling, ABCG8 expression, and their antioxidant properties.

The protective activity of nanomicelle curcumin in bisphenol A-induced cardiotoxicity following subacute exposure in rats.

Bisphenol A (BPA), an estrogenic compound, is used in manufacture of polycarbonate plastics and epoxy resins. Curcumin, the active ingredient of turmeric, is a potent protective compound against cardiac diseases. In this study the protective effect of nanomicelle curcumin on BPA-induced subchronic cardiotoxicity in rats was evaluated. Rats were divided into 6 groups including control, nanomicelle curcumin (50 mg/kg, gavage), BPA (50 mg/kg, gavage), nanomicelle curcumin (10, 25, and 50 mg/kg) plus BPA. The treatments were continued for 4 weeks. Results revealed that BPA significantly induced histophatological injuries including focal lymphatic inflammation, nuclear degenerative changes and cytoplasmic vacuolation, increased body weight, systolic and diastolic blood pressures, malondialdehyde and Creatine phosphokinase-MB level and decreased glutathione content in comparison with control group. In addition, in electrocardiographic graph, RR, QT, and PQ intervals were increased by BPA. Western blot analysis showed that BPA up-regulated phosphorylated p38 (p38-mitogen-activated protein kinase) and JNK (c-jun NH2 terminal kinases), while down-regulated phosphorylated AKT (Protein Kinase B) and ERK1/2 (extracellular signal-regulated protein kinases 1 and 2). However, nanomicelle curcumin (50 mg/kg) significantly improved these toxic effects of BPA in rat heart tissue. The results provide evidence that nanomicelle curcumin showed preventive effects on subchronic exposure to BPA induced toxicity in the heart tissue in rats.

Bisphenol A vascular toxicity: Protective effect of Vitis vinifera (grape) seed extract and resveratrol.

The underlying mechanism of Bisphenol A (BPA)-induced vascular toxicity and the protective role of grape seed extract (GSE) and resveratrol were investigated in vitro and in vivo. Human umbilical vein endothelial cells (HUVECs) were exposed to different concentrations of GSE and resveratrol. Then, BPA was added to the cells and cell viability and effects on the protein level of cell adhesion molecules were measured through MTT and western blotting. Animals were randomly divided into control, GSE (3 and 12 mg·kg-1 ·day-1 ip), resveratrol (100 mg·kg-1 ·day-1 ip), BPA (35 mg·kg-1 ·day-1 , gavage), BPA plus GSE (3, 6, and 12 mg·kg-1 ·day-1 ip), BPA plus resveratrol (25, 50, and 100 mg·kg-1 ·day-1 ip), and BPA plus vitamin E (200 IU/kg per every other day ip). After 2 months, contractile and relaxant responses were evaluated on the isolated aorta. BPA increased the level of aorta malondialdehyde (p < 0.001) and decreased vascular responses to KCl (p < 0.01), phenylephrine (p < 0.001), and acetylcholine (p < 0.01). In HUVECs, BPA (IC50 : 220 µM) increased protein level of vascular cell adhesion molecule (p < 0.05) and cleaved capase3 (p < 0.001). GSE, resveratrol, and vitamin E cotreatment restored toxic effects of BPA in some levels. BPA vascular toxicity was attributed to lipid peroxidation and endothelial dysfunction. The protective role of GSE and resveratrol against BPA-endothelial dysfunction could be attributed to their potent antioxidant properties.

Berberis Vulgaris and Berberine: An Update Review.

Berberine is an isoquinoline alkaloid present in several plants, including Coptis sp. and Berberis sp. Berberine is a customary component in Chinese medicine, and is characterized by a diversity of pharmacological effects. An extensive search in electronic databases (PubMed, Scopus, Ovid, Wiley, ProQuest, ISI, and Science Direct) were used to identify the pharmacological and clinical studies on Berberis vulgaris and berberine, during 2008 to 2015, using 'berberine' and 'Berberis vulgaris' as search words. We found more than 1200 new article studying the properties and clinical uses of berberine and B. vulgaris, for treating tumor, diabetes, cardiovascular disease, hyperlipidemia, inflammation, bacterial and viral infections, cerebral ischemia trauma, mental disease, Alzheimer disease, osteoporosis, and so on. In this article, we have updated the pharmacological effects of B. vulgaris and its active constituent, berberine. Copyright © 2016 John Wiley & Sons, Ltd.

Protective effect of crocin against apoptosis induced by subchronic exposure of the rat vascular system to diazinon.

Research has suggested that natural antioxidant, crocin, an active ingredient of saffron, may protect against diazinon (DZN)-induced toxicity. Although increased production of lipid peroxidation by DZN in rat aorta has been shown previously, the effects of DZN on oxidative stress-induced apoptosis in vascular system have not been evaluated. In this study, the effect of crocin on DZN-induced apoptosis in rat vascular system was investigated. The rats were divided into 7 groups: corn oil (control), DZN (15 mg/kg/day, gavage), crocin (12.5, 25, and 50 mg/kg/day, intraperitoneally (i.p.)) + DZN, vitamin E (200 IU/kg, i.p., 3 days a week) + DZN, and crocin (50 mg/kg/day, i.p.). The treatments were continued for 4 weeks. Levels of apoptotic (Bax, caspase 3, and caspase 9) and antiapoptotic proteins (Bcl2) were analyzed by Western blotting. Transcript levels of Bax and Bcl2 genes were determined using quantitative real-time polymerase chain reaction. Results showed DZN-induced apoptosis by activation of caspase 9 and caspase 3 and by increasing the Bax/Bcl2 ratio (both protein and messenger RNA levels). Crocin and vitamin E inhibited apoptosis induced by DZN. In summary, subchronic exposure to DZN induced caspase-mediated apoptosis, and crocin reduced the toxic effects of DZN by inhibiting apoptosis in aortic tissue.

Effect of exposure to diazinon on adult rat's brain.

Diazinon (DZN), a commonly used agricultural organophosphate insecticide, is one of the major concerns for human health. This study was planned to investigate neurotoxic effects of subacute exposure to DZN in adult male Wistar rats. Animals received corn oil as control and 15 and 30 mg/kg DZN orally by gastric gavage for 4 weeks. The cerebrum malondialdehyde and glutathione (GSH) contents were assessed as biomarkers of lipid peroxidation and nonenzyme antioxidants, respectively. Moreover, activated forms of caspase 3, -9, and Bax/Bcl-2 ratios were evaluated as key apoptotic proteins. Results of this study suggested that chronic administration of DZN did not change lipid peroxidation and GSH levels significantly in comparison with control. Also, the active forms of caspase 3 and caspase 9 were not significantly altered in DZN-treated rat groups. Moreover, no significant changes were observed in Bax and Bcl-2 ratios. This study indicated that generation of reactive oxygen species was probably modulated by intracellular antioxidant system. In conclusion, subacute oral administration of DZN did not alter lipid peroxidation. Moreover, apoptosis induction was not observed in rat brain.

Evaluation of diazinon-induced hepatotoxicity and protective effects of crocin.

Diazinon (DZN) is one of the most widely used insecticides in agricultural pest control. Previous studies have shown that DZN may induce hepatotoxicity. Reactive oxygen species and apoptosis pathways are involved in the toxicity of DZN. Crocin, a constituent of saffron, has hepatoprotective effects due to its antioxidant activity. In this study, we examined the effects of subacute DZN exposure and ameliorating effect of crocin on lipid peroxidation and pathological changes in rat liver. Moreover, protein levels of activated and total caspases-3 and -9 and Bax/Bcl-2 ratio were measured. Five groups of rats were used in the experiment. Corn oil (control), DZN (15 mg/kg per day, orally) and crocin (12.5, 25 and 50 mg/kg per day, intraperitoneally in combination with DZN) were given to male Wistar rats (n = 6) for 4 weeks. The level of malondialdehyde (MDA) increased significantly in DZN group compared with the control group (p < 0.05). MDA level decreased significantly in the group that received DZN plus 25 mg crocin (p < 0.001). No gross or histological evidence of treatment-related damage to the liver after oral exposure to DZN was observed. DZN also induced apoptosis through activation of caspases-9 and -3 and increasing Bax/Bcl-2 ratio. Crocin attenuated the activation of caspases and reduced the Bax/Bcl-2 ratio. It is concluded that subacute exposure to DZN induces oxidative stress-mediated apoptosis and crocin may reduce DZN-induced hepatotoxicity.

Protective effect of crocin on diazinon induced vascular toxicity in subchronic exposure in rat aorta ex-vivo.

CONTEXT: Diazinon (DZN) is a widely used organophosphate insecticide. Although mechanism of DZN cardiovascular toxicity is primarily mediated through inhibition of acetylcholinesterase, however, DZN causes remarkable atropine-insensitive hypotension in rats. It has been proved that oxidative stress is an important mechanism of DZN toxicity especially in chronic exposure. Crocin, an active ingredient of saffron, has been found to antagonize the hypotensive effects of DZN in rats, but do not reverse acetylcholinesterase inhibition. OBJECTIVE: In this study the effects of DZN on contractile and relaxant responses in rat aorta as well as ex-vivo antioxidant actions of crocin have been investigated. MATERIALS AND METHODS: Rats were divided into 7 groups: corn oil (control), DZN (15 mg/kg/day, gavage), crocin (12.5, 25 and 50 mg/kg/day, i.p.) plus DZN, vitamin E (200 IU/kg, i.p., three days a week) plus DZN and crocin (50 mg/kg/day, i.p.) groups. Treatments were continued for 4 weeks. Contractile and relaxant responses were evaluated on the isolated aorta. RESULTS: Our results showed that DZN not only decreased the contractile responses to KCl and Phenylephrine (PE) (p < 0.001), but also attenuated the relaxant response to acetylcholine (ACh) (p < 0.01). Crocin and vitamin E attenuated lipid peroxidation, improved the reduction of contractile responses by KCl and PE and restored the decrease in ACh relaxation in rat aorta. CONCLUSION: DZN induced vascular toxicity which may be due to oxidative stress and not to a cholinergic mechanism. Crocin improved toxic effects of DZN via reducing lipid peroxidation and restoring altered contractile and relaxant responses in rat aorta.

Effects of telmisartan on metabolic syndrome components: a comprehensive review.

Telmisartan is an antagonist of the angiotensin II receptor used in the management of hypertension (alone or in combination with other antihypertensive agents. It belongs to the drug class of angiotensin II receptor blockers (ARBs). Among drugs of this class, telmisartan shows particular pharmacologic properties, including a longer half-life than any other angiotensin II receptor blockers that bring higher and persistent antihypertensive activity. In hypertensive patients, telmisartan has superior efficacy than other antihypertensive drugs (losartan, valsartan, ramipril, atenolol, and perindopril) in controlling blood pressure, especially towards the end of the dosing interval. Telmisartan has a partial PPARγ-agonistic effect whilst does not have the safety concerns of full agonists of PPARγ receptors (thiazolidinediones). Moreover, telmisartan has an agonist activity on PPARα and PPARδ receptors and modulates the adipokine levels. Thus, telmisartan could be considered as a suitable alternative option, with multi-benefit for all components of metabolic syndrome including hypertension, diabetes mellitus, obesity, and hyperlipidemia. This review will highlight the role of telmisartan in metabolic syndrome and the main mechanisms of action of telmisartan are discussed and summarized. Many studies have demonstrated the useful properties of telmisartan in the prevention and improving of metabolic syndrome and this well-tolerated drug can be greatly proposed in the treatment of different components of metabolic syndrome. However, larger and long-duration studies are needed to confirm these findings in long-term observational studies and prospective trials and to determine the optimum dose of telmisartan in metabolic syndrome.

Evaluation of the Protective Effects of Lugol's Solution in Rats Poisoned with Aluminum Phosphide (Rice Tablets).

Aluminum phosphide (AlP) is the main component of rice tablets (a pesticide), which produces phosphine gas (PH3) when exposed to stomach acid. The most important symptoms of PH3 toxicity include, lethargy, tachycardia, hypotension, and cardiac shock. It was shown that Iodine can chemically react with PH3, and the purpose of this study is to investigate the protective effects of Lugol solution in poisoning with rice tablets. Five doses (12, 15, 21, 23, and 25 mg/kg) of AlP were selected, for calculating its lethal dose (LD50). Then, the rats were divided into 4 groups: AlP, Lugol, AlP + Lugol, and Almond oil (as a control). After 4 h, the blood pressure and electrocardiogram (ECG) were recorded, and blood samples were obtained for biochemical tests, then liver, lung, kidney, heart, and brain tissues were removed for histopathological examination. The results of the blood pressure showed no significant changes (P > 0.05). In ECG, the PR interval showed a significant decrease in the AlP + Lugol group (P < 0.05). In biochemical tests, LDH, Ca2+, Creatinine, ALP, Mg2+, and K+ represented significant decreases in AlP + Lugol compared to the AlP group (P < 0.05). Also, the administration of Lugol's solution to AlP-poisoned rats resulted in a significant decrease in malondialdehyde levels and a significant increase in catalase activity (P < 0.05). Histopathological evaluation indicates that Lugol improves changes in the lungs, kidneys, brain, and heart. Our results showed that the Lugol solution could reduce tissue damage and oxidative stress in AlP-poisoned rats. We assume that the positive effects of Lugol on pulmonary and cardiac tissues are due to its ability to react directly with PH3.

Hypotensive activity of auraptene, a monoterpene coumarin from Citrus spp.

CONTEXT: Citrus spp. (Rutaceae) are well-documented for their cardioprotective properties. Auraptene is a bioactive monoterpene coumarin ether abundantly present in the Citrus spp. OBJECTIVE: To investigate the hypotensive activity of auraptene. METHODS: Different groups of normotensive rats (n = 5 in each group) were subjected to single intravenous injections of auraptene (125, 250 and 500 µg/kg), nifedipine (as positive control; 63, 125 and 250 µg/kg) or negative control [DMSO/normal saline (1:3)]. Mean arterial blood pressure (MABP) and heart rate (HR) were evaluated following each treatment. RESULTS: A dose-dependent hypotensive effect was observed following auraptene injection, which was significant at 250 and 500 µg/kg (p < 0.001) but not 125 µg/kg (p > 0.05). With respect to the positive control, nifedipine reduced MABP at all tested doses, dose-dependently and significantly (p < 0.001). The MABP lowering effect of auraptene was found to be significantly lower than that of nifedipine (p < 0.001). CONCLUSION: In light of the present findings, auraptene has moderate hypotensive activity. Further investigations are recommended to explore the effects of higher doses as well as oral administration of this phytochemical.

Protective Effect of Silymarin against Acrolein-Induced Cardiotoxicity in Mice.

Reactive α,ß-unsaturated aldehydes such as acrolein (ACR) are major components of environmental pollutants and have been implicated in the neurodegenerative and cardiac diseases. In this study, the protective effect of silymarin (SN) against cardiotoxicity induced by ACR in mice was evaluated. Studies were performed on seven groups of six animals each, including vehicle-control (normal saline + 0.5% w/v methylcellulose), ACR (7.5 mg/kg/day, gavage) for 3 weeks, SN (25, 50 and 100 mg/kg/day, i.p.) plus ACR, vitamin E (Vit E, 100 IU/kg, i.p.) plus ACR, and SN (100 mg/kg, i.p.) groups. Mice received SN 7 days before ACR and daily thereafter throughout the study. Pretreatment with SN attenuated ACR-induced increased levels of malondialdehyde (MDA), serum cardiac troponin I (cTnI), and creatine kinase-MB (CK-MB), as well as histopathological changes in cardiac tissues. Moreover, SN improved glutathione (GSH) content, superoxide dismutase (SOD), and catalase (CAT) activities in heart of ACR-treated mice. Western blot analysis showed that SN pretreatment inhibited apoptosis provoked by ACR through decreasing Bax/Bcl-2 ratio, cytosolic cytochrome c content, and cleaved caspase-3 level in heart. In conclusion, SN may have protective effects against cardiotoxicity of ACR by reducing lipid peroxidation, renewing the activities of antioxidant enzymes, and preventing apoptosis.

Effect of linalool on morphine tolerance and dependence in mice.

Linalool, a terpene alcohol, has been shown to interact with the opioid system and N-methyl-D-aspartate (NMDA) receptor. Therefore, the effect of linalool on morphine dependence and tolerance was studied. Dependence and tolerance were induced in mice using subcutaneous morphine injections, three times a day (50, 50 and 75 mg/kg /day) for 3 days. To evaluate the effect of agents on the induction of morphine dependence and tolerance, linalool (50, 75 and 100 mg/kg), clonidine (positive control), alpha-2 receptor agonist, (0.1 mg/kg), memantine, NMDA receptor antagonist (positive control), (30 mg/kg) and saline were injected intraperitoneally three times a day for 3 days. To determine the expression of morphine dependence and tolerance, all compounds were injected once intraperitoneally on the day of experiment. The effect of linalool and other agents on dependence were evaluated by counting the number of jumps (induced by naloxone 5 mg/kg). The tolerance was evaluated by the tail-flick test. The results showed that linalool in the induction and expression phase increased the nociception threshold. Linalool (48% and 95.6% at doses 75 and 100 mg/kg, respectively), clonidine and memantine reduced the severity of withdrawal signs in the induction and expression phases. This study indicated that linalool has a significant effect on morphine tolerance and dependence. This effect may be mediated partially through the inhibition of NMDA receptors.