Exploring the multifaceted neuroprotective actions of gallic acid: a review

Much attention has been recently given to the effect of diet compounds on physical and mental health. Gallic acid is a phenolic compound with antioxidant activity. This compound is widely presented in black tea leaves, green tea, apples, grapes, strawberries, and pineapples. During the past years, it has been reported that gallic acid is effective against nervous system's disorders including Alzheimer's disease, Parkinson's disease, ischemia, and reperfusion, depression and anxiety. These indicate that gallic acid can be considered as a valuable agent for nutraceutical interventions. In this study, several clinical studies suggested that gallic acid can improve human health by preventing or delaying the onset of neurological diseases. The present study indicated the neuroprotective features of gallic acid including the pre-clinical evidence for its effects in AD and PD and other diseases related to the nervous system. Significant efforts are required to confirm the neuroprotective effects of gallic acid in treating the diseases related to the nervous system. Keywords:Gallic acid; neurodegenerative diseases; Parkinson; psychiatric disorder

Medicinal plants: Past history and future perspective

Human societies have been in close contact with their environments since the beginning of their formation and used the ingredients of the environment to obtain food and medicine. Awareness and application of plants to prepare food and medicine have been realized through trial and error, and gradually human became able to meet his needs from his surroundings. Information about medicinal plants has long been transmitted gradually and from generation to generation, a human knowledge has gradually become complete with the formation of civilizations and the provision of more facilities. Medicinal plants are used as a medical resource in almost all cultures. Ensuring the safety, quality and effectiveness of medicinal plants and herbal drugs very recently became a key issue in industrialized and developing countries. By standardizing and evaluating the health of active plant-derived compounds, herbal drugs can help the emergence of a new era of the healthcare system to treat human diseases in the future. Awareness of traditional knowledge and medicinal plants can play a key role in the exploitation and discovery of natural plant resources. In order to maintain this knowledge, comprehensive approach and collaboration are needed to maintain historical records on medicinal plants and use these resources in favour of human beings, before they are destroyed forever. Therefore, this review was conducted to investigate and describe the process of using medicinal plants throughout history. This review focuses on the recent various important challenges in quality evaluation of medicinal plants in the authenticity, efficacy, toxicity and consistenc

Phytotherapy in treatment of Parkinson's disease: a review.

Context: Parkinson's disease (PD) is a neurodegenerative disorder due to gradual loss of dopaminergic nerves in the substantia nigra (SN) in the midbrain. PD leads to certain motor disorders including resting tremor, muscle stiffness and slow movement. Medicinal plants have shown positive pharmacological effects in treating different models of PD. Objective: Tendency to use natural products, especially plants, for the treatment of PD has been growing. This article reviews the basic aspects of medicinal plants and their bioactive compounds that could be used to treat PD. Methods: Reliable articles indexed in databases ISI, SID, PubMed, PubMed Central, Scopus and Web of Science were used. A total of 12 plant-derived active ingredients and 18 herbal extracts were included. Different compounds have so far been isolated from plants that affect PD especially by targeting pathways associated with the pathogenesis of the disease. Results: Although some herbal extracts such as Hibiscus asper Hook. f. (Malvaceae), Ginkgo biloba L. (Ginkgoaceae), Carthamus tinctorius L (Asteraceae) and certain active ingredients, such as berberine and curcumin, have shown positive effects in animal models of PD, potential active ingredients and mechanisms of action should be investigated in additional studies. Discussion and conclusions: Despite the wide variety of plants in the world, a limited number of them have been studied for anti-Parkinsonian activity, and therefore, there are numerous perspectives in this field for future studies on plants and their bioactive compounds. KEYWORDS: ; Dopaminergic receptors; L-DOPA; curcumi

Progesterone exerts antidepressant-like effect in a mouse model of maternal separation stress through mitigation of neuroinflammatory response and oxidative stress

Context: Experiencing early-life adversity plays a key role in the development of mood disorders in adulthood. Experiencing adversities during early life period negatively affects brain development. Sex steroids such as progesterone affect the brain structure and functions and subsequently affects behaviour. Objective: We assess the antidepressant-like effect of progesterone in a mouse model of maternal separation (MS) stress, focussing on its anti-neuroinflammatory and antioxidative effects. Materials and methods: NMRI mice were treated with progesterone (10, 50, and 100 mg/kg, i.p., respectively) for 14 days. Valid behavioural tests including forced swimming test (FST), splash test and open field test (OFT) were used. Quantitative reverse transcription-PCR (qRT-PCR) was used for evaluation of genetic expression in the hippocampus. Antioxidant capacity was assessed by the FRAP method and the level of malondialdehide by TBA. Results: MS provoked depressive-like behaviour in mice. Treatment of MS mice with progesterone increased the grooming activity time in the splash test and decreased the immobility time in the FST. In addition, progesterone decreased the expression of inflammatory genes related to neuroinflammation (IL-1 beta, TNF-alpha, TLR4 and NLRP3) as well as increased the antioxidant capacity and decreased the lipid peroxidation (MDA) in the hippocampus. Discussion and Conclusion: Administration of progesterone significantly mitigated the negative effects of MS on behaviours relevant to depressive-like behaviour as well as attenuated neuro-immune response and oxidative stress in the hippocampus of MS mice. In this context, we conclude that progesterone, at least partially, via attenuation of oxidative stress and neuroinflammation, exerts antidepressant-like effects

Entinociceptive effects of Euphorbia helioscopia extract on Balb/c mice

Background and aims: Euphorbia helioscopia has multiple pharmacological activities, such as antibacterial, antiviral, antifungal,anticancer and/or antitumor, allelopathic, anti-allergic and anti-asthmatic, antioxidant, antinociceptive effect. The aim of the study was to evaluate the antinociceptive activities of Euphorbia helioscopia extract in Balb/c mice, as well as the total flavonoids, phenolic contents, and antioxidant activities of the extract. Methods: In this study, 90 Balb/c mice were randomly designated into 9 groups. Group 1 received normal saline, groups 2 to 7 received different doses of the E. helioscopia hydroethanolic extract (i.e., 0.05, 0.1, 0.2, 0.4, 2, & 8 mg/kg, i.p.).In addition, groups 8 and 9 received naloxone (1 mg/kg) and extract (8 mg/kg) plus naloxone (1 mg/kg), respectively (Naloxone was injected 15 minutes after extract administration). Then, pain response was evaluated for 30 minutes after the injection of 20 µL formalin (1.5%) in the plantar surface of the mice foot. Further, the beta-carotene-linoleate method was used for measuring antioxidant capacity. Finally, total phenolic and flavonoid content were measured based on Folin-Ciocalteu colorimetric and aluminum chloride colorimetric methods, respectively. Results: Total phenol and flavonoid content were 49.43 ± 1.8 mg GAE/g dried extract and 30.19 ± 1.96 mg rutin/g dried extract, respectively. Our results showed that during the first 5 minutes (the acute pain step), a significant difference (P<0.05) was observed between the control group and the group which received the E. helioscopia hydroethanolic extract (8 mg/kg). In the next 25 minutes (the chronic pain step), a significant difference (P<0.05) was found between the control group and the group which received 0.1 and 8 mg/kg doses of the extract. Based on the results, naloxone was unable to reverse the antinociceptive effects of the extract and the maximum antioxidant activity of the extract was 1.641 mg/g of rutin equivalent. Conclusion: In general, this study supports the use of the E. helioscopia extract in folk medicine as the analgesic agent and calls for further investigations regarding elucidating its mechanism of action. Eventually, our findings revealed that the extract of E. helioscopia possessed either antinociceptive or anti-oxidative activities. Keywords: Euphorbia helioscopia, Pain, Mice, Formalin test, Antioxidant activit

Minocycline through attenuation of oxidative stress and inflammatory response reduces the neuropathic pain in a rat model of chronic constriction injury

Objectives: Several lines of evidence showed that minocycline possesses antioxidant and anti-inflammatory properties. This study aimed to demonstrate the effects of minocycline in rats subjected to chronic constriction injury (CCI). Materials and Methods: In this study four groups (n = 6-8) of rats were used as follows: Sham, CCI, CCI + minocycline (MIN) 10 mg/Kg (IP) and CCI + MIN 30 mg/Kg (IP). On days 3, 7, 14, and 21 post-surgery hot-plate, acetone, and von Frey tests were carried out. Finally, Motor Nerve Conduction Velocity Evaluation (MNCV) assessment was performed and spinal cords were harvested in order to measure tissue concentrations of TNF_α, IL-1β, Glutathione peroxidase (GPx), Superoxide dismutase (SOD) and Malondialdehyde (MDA). Extent of perineural inflammation and damage around the sciatic nerve was histopathologically evaluated. Results: Our results demonstrated that CCI significantly caused hyperalgesia and allodynia twenty-one days after CCI. MIN attenuated heat hyperalgesia, cold and mechanical allodynia and MNCV in animals. MIN also decreased the levels of TNF_α and IL-1β. Antioxidative enzymes (SOD, MDA, and GPx) were restored following MIN treatment. Our findings showed that MIN decreased perineural inflammation around the sciatic nerve. According to the results, the neuropathic pain reduced in the CCI hyperalgesia model using 30 mg/kg of minocycline. Conclusion: It is suggested that antinociceptive effects of minocycline might be mediated through the inhibition of inflammatory response and attenuation of oxidative stress

Quercetin through mitigation of inflammatory response and oxidative stress exerts protective effects in rat model of diclofenac-induced liver toxicity

Context: Diclofenac (DIC) is known for its anti-inflammatory and analgesic properties but liver toxicity is one of the main targets to use this drug. Previous studies have demonstrated that quercetin may decrease the toxicity of synthetic drugs. Aim: To assess the protective effect of quercetin against DIC-induced liver toxicity in rats. Methods: The rats exposed to DIC (50 mg/kg; i.p.) were treated with different doses of quercetin (20, 40 and 80 mg/kg). The levels of glutathione peroxidase (GPx), superoxide dismutase (SOD), intracellular glutathione (GSH) and catalase (CAT) in the liver tissue were assessed. Results: Results indicated a significant decline in above-mentioned factors in DIC-alone treated group compared to the control group. Also, levels of the triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C), total bilirubin, alkaline phosphatase (ALP), nitrite content, alanine aminotransferase (ALT), malondialdehyde (MDA), serum tumor necrosis factor-α (TNF-α), serum interleukin-1β (IL-1β), aspartate aminotransferase (AST), and inflammatory cytokines were evaluated and results indicted remarkable elevation in these factors in DIC-alone treated group compared to the control group. Treatment with quercetin caused a significant elevation in GPx, SOD, GSH, CAT and a significant reduction in levels of TG, TC, LDL-C, VLDL-C, total bilirubin, ALP, nitrite content, ALT, MDA, serum TNF-α, serum IL-1β, AST and inflammatory cytokines in DIC-alone treated group compared to the control group (p<0.05). Histopathological alterations were also improved following quercetin administration. Conclusions: Quercetin may exert a protective effect against DIC-induced liver toxicity in rats through mitigation of oxidative stress and inflammatory response

Inhibitory effects of Nigella sativa seed oil on the testosterone-induced benign prostatic hyperplasia in rats

Background: Benign prostatic hyperplasia (BPH) is the most prevalent disease of the prostate in elderly men. Since Nigella sativa has been reported to show various pharmacological effects, this study was conducted to examine the effect of N. sativa seed oil on experimental BPH. Methods: The oil was extracted using the cold-pressing method. Fifty rats were divided into five groups of 10 each as follows: Group 1 orally (p.o.) received normal saline; groups 2e5 were castrated and subcutaneously received 5 mg/kg testosterone propionate for four weeks. Group 2, namely, BPH model, underwent no further treatment, Groups 3 and 4 were treated with 400 mg/kg and 800 mg/kg N. sativa seed oil, Group 5 received finasteride (0.5 mg/kg, p.o.) for 28 days. All groups received repeated testosterone injections for the following four weeks after BPH induction. After the treatments, rats were sacrificed and the prostate tissues removed. Wet weight, prostatic volume (PV) and prostatic index (PI) were determined. Serum prostate-specific antigen (PSA), dihydrotestosterone (DHT), malondialdehyde (MDA) and antioxidant levels were determined. Results: Our results showed that oral treatment with 400 and 800 mg/kg N. sativa oil led to a significant decrease in PI, PV, DHT concentration, PSA, and serum MDA level, and also significantly increased serum antioxidant capacity. Conclusions: The study demonstrated that the oil seed exerted anti-BPH effects which may be associated with its antioxidant properties in vivo