The Role of Urtica Dioica (Urticaceae) in the Prevention of Oxidative Stress Caused by Tourniquet Application in Rats

Antioxidant Activity of Urtica dioica: An Important Property Contributing to Multiple Biological Activities

Urtica dioica (UD) is a multi-functional plant known to be used as both food and medicine from ancient times. The plant has the potential to be used as a fertilizer and for biological pest control. It is also used in textile and related industries for its quality fibers. In the recent past, the plant has received great attention for its numerous important biological activities and food applications. The antioxidant activity of UD is the crucial factor supporting its important biological activities, such as anticancer, antidiabetic and anti-inflammatory properties. The antioxidant activity of UD is also found to be protective in different organs, including the brain, liver, lungs, kidney, ovary, and uterus, and may also be protective against diseases associated with these organs. Few clinical studies have endorsed the antioxidant potential of UD in patients. The current work is an attempt to comprehensively compile and discuss the antioxidant activity of UD from in vitro, in vivo and human studies. The insights of the current study would be helpful in getting a panoramic view of the antioxidant potential of UD, and provide direction for optimizing and developing it for therapeutic applications against important diseases and conditions in the near future.

The effect of Urtica dioica extract on oxidative stress, heat shock proteins, and brain histopathology in multiple sclerosis model

Multiple sclerosis (MS) results from the destruction of myelin and focal inflammation. The study aimed to evaluate the effect of hydroalcoholic extract of Urtica dioica on oxidative stress, heat shock proteins, and brain histopathology in multiple sclerosis model. Sixty male C57BL/6 mice were divided into six groups of 10. Groups included positive control, negative control, and treatment groups with U. dioica extract at a dose of 50, 100, 200, and 400 mg/kg for 21 days (three times a week). The MS model was developed by a diet containing 0.2% cuprizone for 6 weeks. A section of brains was evaluated with Luxol Fast Blue staining and the other part evaluated with heat shock protein (HSP) kits 60 and 70, total antioxidant capacity (TAC), and malondialdehyde (MDA). In sections of corpus callosum, the highest amount of myelin was observed in the negative controls, while the use of cuprizone in the positive controls caused the destruction and reduction of myelin. The use of U. dioica extract in therapeutic groups except at a dose of 50 mg/kg could reduce myelin degradation to some extent and lead to remyelination. However, myelin levels in treatment groups were not significantly different from any of the negative and positive controls. Although HSP60 decreased in the treatment groups, there was no significant difference between the positive and negative controls. Treatment with this extract significantly reduced the amount of HSP70 compared with the positive controls. The decreased TAC and increased MDA in positive controls indicated oxidative stress, respectively. Furthermore, the extract led to an increase and decrease of TAC and MDA in the treatment groups, respectively. However, only the MDA level was significantly different from that of the positive controls. Therefore, the antioxidant effects of U. dioica extract could decrease cuprizone-induced oxidative stress and be effective in improving demyelination.

Synergistic effects of high-intensity interval training (HIIT) and intake of nettle on serum levels of chemerin and beta cells function in type 2 diabetic rats

OBJECTIVES

This animal study aimed to demonstrate the synergistic effect of high-intensity interval training (HIIT) and alcoholic extract of nettle on serum chemerin and beta cells function in type 2 diabetic male rats.

METHODS

Thirty-two STZ-induced diabetic male Wistar rats were randomly divided into four groups including the control group, the supplemented group with 200 mg/day of nettle, the training group with five sessions per week of HIIT, and the group with combined nettle and HITT intervention. Body weight, lipid profile, beta cells function, and chemerin level were assessed after eight weeks of the intervention.

RESULTS

The values of chemerin significantly decreased in combined HIIT and nettle intervention group compared to the control group (p=0.001). The levels of glucose and insulin decreased significantly in nettle group, exercise group, and combined HIIT and nettle group (p=0.001).

CONCLUSIONS

The present study found that intense interval exercise with the consumption of alcoholic extract of nettle can affect the performance of beta cells, glucose, and insulin. Future human studies are warranted.

Perceived health properties of wild and cultivated food plants in local and popular traditions of Italy: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Many wild and cultivated plants are rich in mineral elements and bioactive compounds and are consumed for health purposes. Studies have demonstrated the curative properties of many of these food plants. In this paper, we discuss the properties of several plants with potential health benefits that have previously received little attention.

AIM OF THE STUDY

This review provides an overview and critical discussion of food plants perceived by informants (emic view) as healthy or used as 'food medicine' in Italy. Pharmacological activity of these plants is explored, based upon published scientific research (etic view). Preparation methods, taste perception, toxicity and various potentialities of some food plants are also discussed.

MATERIALS AND METHODS

The present review includes literature available from 1877 to 2012. The information was collected from books, scientific papers, and abstracts that reported any plants used as food medicine in Italy. The perceived health properties were analyzed in the framework of recent international phytochemical and phytopharmacological literature.

RESULTS

A total of 67 edible wild plants and 18 cultivated vegetables, distributed into 20 families, were reported by informants (in literature). Several plants were highly cited (e.g., Taraxacum officinale Webb., Crepis vesicaria L., Allium cepa L., Allium sativum L.). The most frequent health properties attributed to edible plants by the informants were: laxative (22 species), diuretic (15), digestive (11), galactagogue (8), antitussive (cough) (8), hypotensive (7), tonic (7), sedative (7), hypoglycemic (6).

CONCLUSIONS

Some edible plants are promising for their potential health properties, such as Crepis vesicaria L., Sanguisorba minor Scop. and Sonchus oleraceus L. Several wild species were perceived by informants to maintain health but have never been studied from a phytochemical or pharmacological point of view: e.g., Asparagus albus L., Crepis leontodontoides All., Hyoseris radiata L. subsp. radiata, Phyteuma spicatum L.

Cytogenetic damage after ischemia and reperfusion

Tourniquets are often used to provide a bloodless operating field. However, they carry the risk of adverse effects caused by DNA damage from the free radicals generated during postischemic reperfusion of the blood. The aim of this study was to evaluate the cytogenetic damage caused by postischemic reperfusion on peripheral lymphocytes of five women and six men undergoing total knee arthroplasty "bloodless" operation using samples received before, during, immediately, and 1 h after the operations. The sister chromatid exchange assay was applied to peripheral blood lymphocyte cultures and the levels of sister chromatid exchanges were analyzed as a quantitative index of genotoxicity, along with the values of mitotic index and proliferation rate index as qualitative indices of cytotoxicity and cytostaticity, respectively. We observed that postischemic reperfusion induced cytogenetic damages specifically through reperfusion. DNA effects were most pronounced after tourniquet release and declined afterward without returning to preischemic baseline values. Our findings suggest the presence of a functional association between postischemic reperfusion and cytogenetic damage that may have important clinical implications.

The protective activity of Urtica dioica leaves on blood glucose concentration and beta-cells in streptozotocin-diabetic rats

This study was done to determine the protective activity of the hydroalcholic extract of Urtica dioica leaves on Hyperglycemia and beta-cells in hyperglycemic rats. Thirty Wistar rats were allocated in groups of normal, Diabetic and treatment. Hyperglycemia in Rats induced by 80 mg kg(-1) streptozotocin. In treatment group, animals received hydroalcholic extract of Urtica dioica 100 mg kg(-1) day(-1) for five days, intraperitoneally and then hyperglycemia induced by streptozotocin. The blood glucose concentration was measured by using a Glucometer in 1st, 3rd and 5th weeks. In the end of 5th weeks the animals in each group were sacrificed by anesthesia and whole pancreas in three groups extracted and fixed in bouin's fluid and stained by chromealum hematoxiline-phloxine and beta cells were counted in three groups by Olympus microscope. Mean +/- SE of blood glucose concentrations in the end of fifth weeks were 99.4 +/-5.0, 454.7 +/- 34.5 and 303.6 +/- 100.6 in control, diabetic and treatment groups, respectively (p < 0.05). The percentages of beta-cells in control, diabetic and treatment groups were 73.6, 1.9 and 22.9%, respectively. The percentage of beta-cells in treatment group comparing with diabetic group was significant (p < 0.05). This study showed that the protective administration of hydroalcholic extract of Urtica dioica has hypoglycemic effect and protective activity of beta-cells of langerhans in hyperglycemic rats.

A comprehensive review on nettle effect and efficacy profiles, Part I: herba urticae

Nettle herb is recommended for complaints associated with rheumatoid arthritis, osteoarthritis and urinary tract infections. We therefore conducted a comprehensive review of the literature to summarize the pharmacological and clinical effects of this plant material. Although clinical and experimental studies suggest that nettle herb has some anti-inflammatory properties, clinical evidence beyond doubt is lacking. Nettle preparations exert a number of promising in vitro and in vivo effects, however, further studies are needed to support these results and to find out if these effects are surrogates for clinical relevant effects in humans.

Zinc may protect remote ocular injury caused by intestinal ischemia reperfusion in rats

Remote organ injury represents the oxidative damage, which occurs in various organs away from the tissues exposed to ischemia-reperfusion insult. Hypothesizing that the eye may be susceptible to this type of tissue damage, we investigated the effect of splanchnic ischemia-reperfusion on the chorio-retinal tissue in Sprague-Dawley rats. Four groups, each consisting of 10 male rats, were designed for the study. Ischemia-reperfusion was introduced by clamping superior mesenteric artery for 1 hour, followed by reperfusion for 90 min (IR group). In another group, the same operation was performed except that zinc aspartate (50 mg/kg) was given intra-peritoneally 15 min before the opening of the clamp (Zn-IR group). As control (sham group), the abdomen was opened without any intervention on superior mesenteric artery. The other group was given Zn after opening of abdomen without any intervention on superior mesenteric artery (Zn-sham group). After the choroid and the retina were dissected from the eye, malondialdehyde, superoxide dismutase, catalase and nitric oxide (NO) were measured in the collected eye tissues. We found that the levels of malondialdehyde, an indicator for lipid peroxidation, were higher in the chorio-retinal tissue of IR group compared to Zn-IR, Zn-sham or sham group (p < 0.05). The oxidative stress in Zn-IR group was not higher than that of sham group. Treatment with zinc decreased NO levels but had no noticeable effect on the level of antioxidant enzymes. Our study indicates that remote organ injury is induced in the eye during splanchnic ischemia-reperfusion and that zinc may be beneficial to ameliorate remote ocular injury.