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Experimental warming alleviates the adverse effects from tropospheric ozone on two urban tree species
2021
Xu, Sheng | Wang, Yijing | Zhang, Weiwei | Li, Bo | Du, Zhong | He, Xingyuan | Chen, Wei | Zhang, Yue | Li, Yan | Li, Maihe | Schaub, Marcus
Atmospheric warming and increasing tropospheric ozone (O₃) concentrations often co-occur in many cities of the world including China, adversely affecting the health status of urban trees. However, little information is known about the combined and interactive effects from increased air temperature (IT) and elevated O₃ (EO) exposures on urban tree species. Here, Ginkgo biloba and Populus alba ‘Berolinensis’ seedlings were subjected to IT (+2 °C of ambient air temperature) and/or EO (+2-fold ambient air O₃ concentrations) for one growing season by using open-top chambers. IT alone had no significant effect on physiological metabolisms at the early growing stage, but significantly increased photosynthetic parameters, antioxidative enzyme activities (P < 0.05). EO alone decreased physiological parameters except for increased oxidative stress. Compared to EO exposure alone, plants grown under IT and EO combined showed higher antioxidative and photosynthetic activity. There was a significant interactive effect between IT and EO on net photosynthetic rate, stomatal conductance, water use efficiency, the maximum quantum efficiency of PSII photochemistry, the actual quantum efficiency of PSII, enzyme activities, aboveground biomass and root/shoot ratio (P < 0.05), respectively. These results suggested that during one growing season, IT mitigated the adverse effect of EO on the tested plants. In addition, we found that G. biloba was more sensitive than P. alba ‘Berolinensis’ to both IT and EO, suggesting that G. biloba may be a good indicator species for climate warming and air pollution, particularly under environmental conditions as they co-occur in urban areas.
Afficher plus [+] Moins [-]Quantifying the particulate matter accumulation on leaf surfaces of urban plants in Beijing, China
2017
Shi, Junna | Zhang, Gang | An, Hailong | Yin, Weilun | Xia, Xinli
Particulate matter is potentially harmful to human health but green tree species act as air filters to adhere these particulates. The elemental composition, number density, and size fractions of particles on leaf surfaces of 14 urban green from Xizhimen overpass and the Olympic Forest Park in Beijing, China were examined by scanning electron microscopy and X-ray energy dispersive spectrometry. Particles that accumulated on leaves were comprised mainly of C, O, Si, Ca, Fe, and Pb. The number density of particles was 50,961.5 mm−2, and 52.9% and 25% of the particles were submicron (<1 μm) and fine (<2.5 μm), respectively. The densities and size fractions of the particles deposited on the adaxial and abaxial side of leaves were significantly different, and 24% of the particles were deposited on the abaxial side of leaves. The densities of the particles in four size fractions differed significantly among the species at the two sampling sites. Salix matsudana, Euonymus japonicus, Magnolia denudate, Sophora japonica, Amygdalus persica, and Salix babylonica efficiently captured all particle sizes on their leaf surfaces. S. matsudana, E. japonicus, M. denudate, S. japonica, Fraxinus chinensis, and Ginkgo biloba efficiently captured submicron and fine particles, which can have serious effects on human health. These differences among species provide more insight into the sink capacity of green tree species, and the efficiencies of plant species for trapping particulates can be used to guide urban tree planning and decrease air pollution.
Afficher plus [+] Moins [-]Characteristics of biogenic volatile organic compounds emitted from major species of street trees and urban forests
2022
Ahn, Ji-Won | Dinh, Trieu-Vuong | Park, Shin-Young | Choi, In-Young | Pak, Ch'an-yŏl | Son, Youn-Suk
Emission characteristics of biogenic volatile organic compounds (BVOCs) (such as isoprene and monoterpenes) emitted from major species of street trees and urban forests by variations in temperature and photosynthetically active radiation (PAR) were investigated. The isoprene and monoterpene emission rates from Prunus sargentii, Ginkgo biloba, Zelkova serrata and Taxus cuspidata were meager. In contrast, the isoprene and monoterpene emission rates from Metasequoia glyptostroboides were very high. In particular, the emission of α-pinene from Metasequoia glyptostroboides was over 10,000 times higher than that from Ginkgo biloba. The patterns of isoprene emissions from the four tree species except for Metasequoia glyptostroboides concerning temperature and PAR were difficult to determine because the emission rate is very low. However, monoterpene emissions from all five tree species were clearly affected by temperature and PAR. These results showed that the characteristics of isoprene and monoterpene emissions differed depending on the tree species. Regarding monoterpene composition, α-pinene (81.3%) accounts for the majority of total monoterpenes from Metasequoia glyptostroboides. This could be a critical consideration when planting trees in an urban forest because BVOC emissions (e.g., α-pinene) have been well known to affect ground-level ozone formation rate via photochemical reaction with NOX. Since Metasequoia glyptostroboides showed relatively high BVOC emissions, the use of this type of tree in an urban forest with relatively high nitrogen oxide emissions should be carefully considered.
Afficher plus [+] Moins [-]Ginkgo biloba attenuates aluminum lactate-induced neurotoxicity in reproductive senescent female rats: behavioral, biochemical, and histopathological study
2019
Verma, Sonia | Ranawat, Pavitra | Sharma, Neha | Nehru, Bimla
Extensive use of aluminum (Al) in industry, cooking utensils, and wrapping or freezing the food items, due to its cheapness and abundance in the environment, has become a major concern. Growing evidence supports that environmental pollutant Al promotes the aggregation of amyloid beta (Aβ) in the brain, which is the main pathological marker of Alzheimer’s disease (AD). Further, AD- and Al-induced neurotoxic effects are more common among women following reproductive senescence due to decline in estrogen. Though clinically Ginkgo biloba extract (GBE) has been exploited as a memory enhancer, its role in Al-induced neurotoxicity in reproductive senescent female rats needs to be evaluated. Animals were exposed to intraperitoneal dose (10 mg/kg b.wt) of Al and oral dose (100 mg/kg b.wt.) of GBE daily for 6 weeks. A significant decline in the Al-induced Aβ aggregates was observed in hippocampal and cortical regions of the brain with GBE supplementation, as confirmed by thioflavin (ThT) and Congo red staining. GBE administration significantly decreased the reactive oxygen species, lipid peroxidation, nitric oxide, and citrulline levels in comparison to Al-treated rats. On the contrary, a significant increase in the reduced glutathione, GSH/GSSG ratio as well as in the activities of antioxidant enzymes was observed with GBE administration. Based on the above results, GBE prevented the neuronal loss in the hippocampus and cortex, hence caused significant improvement in the learning and memory of the animals in terms of AChE activity, serotonin levels, Morris water maze, and active and passive avoidance tests. In conclusion, GBE has alleviated the behavioral, biochemical, and histopathological alterations due to Al toxicity in rats. However, molecular studies are going on to better understand the mechanism of GBE protection against the environmental toxicant Al exposure. Graphical abstract .
Afficher plus [+] Moins [-]Biochemical, molecular and cytological impacts of alpha-lipoic acid and Ginkgo biloba in ameliorating testicular dysfunctions induced by silver nanoparticles in rats
2022
Tohamy, Hossam G. | Lebda, Mohamed A. | Sadek, Kadry M. | Elfeky, Mohamed S. | El-Sayed, Yasser S. | Samak, Dalia H. | Hamed, Heba S. | Abouzed, Tarek K.
Silver nanoparticles (AgNPs) are commonly utilized in medicine. However, they have negative effects on the majority of organs, including the reproductive system. AgNPs were reported to be able to reach the testicular tissues due to their nano size, which allows them to pass through blood-testicular barriers. The goal of this study was to see if alpha-lipoic acid (LA) or Ginkgo biloba (GB) might protect adult rat testes after intraperitoneal injection of AgNPs. Forty male healthy adult Wister albino rats were randomly assigned to four groups: control, AgNPs-intoxicated group intraperitoneally injected AgNPs 50 mg/kg b.w, 3 times a week; LA + AgNPs group intoxicated with AgNPs and orally gavaged with 100 mg LA/kg b.w; and GB + AgNPs group injected with AgNPs and orally given GB extract 120 mg/kg b.w for 30 consecutive days. Biochemical changes (testosterone, ACP, and prostatic acid phosphatase), oxidative indices, mRNA expression of proapoptotic (BAX) and anti-apoptotic (BCL-2) biomarkers, histological, and immunohistochemical changes in testicular tissues were investigated. Significant decrease in serum testosterone level and elevation in ACP and PACP enzyme activity in AgNPs-treated rats. As well, there were lowering in tGSH, GSH GR, GPx, and elevation in MDA and GSSG values. AgNPs-exposed rats expressed downregulation of testicular thirodexin-1 (Txn-1), transforming growth factor-1β (TGF-1β), anti-apoptotic (BCL-2), and upregulaion of proapoptotic biomarkers (BAX) mRNA expressions. Strong positive action to BAX and lowering the action of Ki-67 antibody were observed. Because of their antioxidant, anti-inflammatory, and anti-apoptotic properties, cotreatment with LA or GB could be beneficial in reducing the harmful effects of AgNPs on the testicles.
Afficher plus [+] Moins [-]Anti-kindling effect of Ginkgo biloba leaf extract and L-carnitine in the pentylenetetrazol model of epilepsy
2022
Essawy, Amina E. | El-Sayed, Soad Ahmed | Tousson, Ehab | Abd El-gawad, Horeya S. | Alhasani, Reem Hasaballah | Abd Elkader, Heba-Tallah Abd Elrahim
Epilepsy is one of the most common serious brain disorders, affecting about 1% of the population all over the world. Ginkgo biloba extract (GbE) and L-carnitine (LC) reportedly possess the antioxidative activity and neuroprotective potential. In this report, we investigated the possible protective and therapeutic effects of GbE and LC against pentylenetetrazol (PTZ)-induced epileptic seizures in rat hippocampus and hypothalamus. Adult male albino rats were equally divided into eight groups: control, GbE (100 mg/kg), LC (300 mg/kg), PTZ (40 mg/kg), protective groups (GbE + PTZ and LC + PTZ), and therapeutic groups (PTZ + GbE and PTZ + LC). The oxidative stress, antioxidant, and neurochemical parameters, viz., malondialdehyde (MDA), nitric oxide (NO), reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), acetylcholine esterase (AchE), dopamine (DA), norepinephrine (NE), and serotonin (5-HT), in the hippocampal and hypothalamic regions have been evaluated. PTZ injection leads to an increase in the seizure score, the levels of MDA and NO, and to a decrease in the activity of GSH, SOD, CAT, and GPx. Besides, monoamine neurotransmitters, DA, NE, and 5-HT, were depleted in PTZ-kindled rats. Furthermore, PTZ administration caused a significant elevation in the activity of AchE. Hippocampal and hypothalamic sections from PTZ-treated animals were characterized by severe histopathological alterations and, intensely, increased the ezrin immunolabeled astrocytes. Pre- and post-treatment of PTZ rats with GbE and LC suppressed the kindling acquisition process and remarkably alleviated all the aforementioned PTZ-induced effects. GbE and LC have potent protective and therapeutic effects against PTZ-induced kindling seizures via the amelioration of oxidative/antioxidative imbalance, neuromodulatory, and antiepileptic actions.
Afficher plus [+] Moins [-]In vivo protective effects of Ginkgo biloba L. leaf extract against hydrogen peroxide toxicity: cytogenetic and biochemical evaluation
2020
Yalçın, Emine | Çavuşoğlu, Kültiğin | Acar, Ali | Yapar, Kürşad
In this study, the protective effects of Ginkgo biloba leaf extract (GbE) against toxicity induced by hydrogen peroxide (H₂O₂) in Swiss albino mice were investigated. Abnormal metaphase number (AMn), mitotic index (MI), micronucleus (MN), and chromosomal abnormalities (CAs) were analyzed for cytogenetic effects. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), blood urea nitrogen (BUN), creatinine, glutathione (GSH), and malondialdehyde (MDA) levels in liver and kidney organs were investigated as indicators of biochemical toxicity. Six experimental groups were formed as a control and treatment group, each containing six animals. The mice in the control group were given tap water, while the mice in the administration group received two different doses of GbE and H₂O₂ for 45 consecutive days. It was observed that H₂O₂ administration caused a significant decrease in MI compared to the control group and caused a significant decrease in the frequency of AMn, MN, and CAs. Chromatid break was the most common type of CAs induced by H₂O₂, and the other CAs types observed in this study were chromosome break, fragment, dicentric, gap, and ring. It has been determined that GbE treatment decreases the clastogenic effects of H₂O₂ and reduces the MN and CAs frequency and causes a re-increase in mitotic cell numbers. It was determined that H₂O₂ administration caused changes in biochemical parameters and resulted in significant increases in serum AST, ALP, ALT, BUN, and creatinine levels. However, the level of MDA, which is an indicator of oxidative damage, increased, and GSH level decreased in liver and kidney tissues. Oxidative damage caused by H₂O₂ in liver and kidney tissues was improved, and all biochemical parameters tested were found to be ameliorated after GbE treatment. This improvement was dependent on the dose of GbE, and improvement in 150 mg/kg bw GbE was found to be more prominent. As a result, the GbE can be used as an antioxidant nutritional supplement to protect against the toxic effects of environmental agents such as H₂O₂.
Afficher plus [+] Moins [-]Polycyclic aromatic hydrocarbons in the leaves of twelve plant species along an urbanization gradient in Shanghai, China
2017
Liang, Jing | Fang, Hailan | Zhang, Taolin | Wang, Xingxiang
Plants, particularly their leaves, play an important role in filtering both gas-phase and particle-phase polycyclic aromatic hydrocarbons (PAHs). However, many studies have focused on the accumulation and adsorption functions of plant leaves, possibly underestimating the effects that plants have on air quality. Therefore, eight tree species from different locations in Shanghai were selected to assess PAH filtering (via adsorption and capture) using washed and unwashed plant leaves. The differences in the total PAH contents in the washed leaves were constant for the different species across the different sampling sites. The PAH levels decreased in the following order: industrial areas > traffic areas > urban areas > background area. The PAH compositions in the different plant leaves were dominated by fluorene (Fle), phenanthrene (Phe), anthracene (Ant), chrysene (Chr), fluoranthene (Flu), and pyrene (Pyr); notably, Phe accounted for 49.4–76.7% of the total PAHs. By comparing the PAH contents in the washed leaves with the PAH contents in the unwashed leaves, Pittosporum tobira (P. tobira), Ginkgo biloba (G. biloba), and Platanus acerifolia (P. acerifolia) were found to be efficient species for adsorbing PAHs, while Osmanthus fragrans (O. fragrans), Magnolia grandiflora (M. grandiflora), and Prunus cerasifera Ehrh. (P. cerasifera Ehrh.) were efficient species for capturing PAHs. The efficiencies of the plant leaves for the removal of PAHs from air occurred in the order of low molecular weight > medium molecular weight > high molecular weight PAHs.
Afficher plus [+] Moins [-]Immunostimulating effects of Ginkgo biloba extract against toxicity induced by organophosphate pesticide, diazinon in rainbow trout, Oncorhynchus mykiss: innate immunity components and immune-related genes
2019
Hajirezaee, Saeed | Rafieepour, Ahmad | Shafiei, Shafigh | Rahimi, Ruhollah
The immunostimulating and therapeutic properties of Ginkgo biloba (GB) have always been the focus of traditional medicine over thousands of years. During last decade, special attentions were paid to use of GB in aquaculture to enhance fish health and survival. In the present study, we investigated for the first time the immunogenic effects of dietary GB against oxidative and toxicity induced by organophosphate pesticide, diazinon. In non-diazinon-exposed fish, the plasma total immunoglobulin, lysozyme activity, and peroxidase activity significantly elevated after 60-day experiment in fish supplemented with 1 and 2 g GB/kg diet (p < 0.05). The respiratory burst activity and complement activity significantly increased only in groups supplemented with 0.5 g GB/kg diet (p < 0.05). Furthermore, the peroxidase activity, total immunoglobulin, and lysozyme activity significantly declined in groups supplemented with 4 g GB/kg diet during feeding trial (p < 0.05). There were no significant differences in expression of interleukin 1 beta (IL-1β) and transforming growth factor beta 1 (TGF-β1) genes in kidney between control group (non-GB-supplemented fish) and GB-supplemented fish (p > 0.05). In diazinon-exposed fish, all immunity components significantly decreased during exposure in control and those fed 0.5 and 4 g GB/kg diet (p < 0.05). In fish fed 1 and 2 g GB/kg diet, no alternations were found in immunity components during exposure period (p > 0.05). In addition, diazinon induced the expression of IL-1β and TGF-β1 genes in control and fish fed 0.5 and 4 g GB/kg diet (p < 0.05). No significant changes were observed in expression of IL-1β and TGF-β1 genes in fish supplemented with 1 and 2 g GB/kg (p > 0.05). In conclusion, the results of the present study suggest an immunogenic role for dietary GB at optimum dietary levels (1–2 g GB/kg diet) against toxicity induced by diazinon. Nevertheless, GB at high dietary levels (4 g GB/kg diet) showed immunosuppressive effects, which makes it necessary to optimize its levels in diet.
Afficher plus [+] Moins [-]What is the possible therapeutic effect of Ginkgo biloba on gastric ulcer induced by ammonia in albino rats?
2020
El-Medany, Azza | Guemei, Aida Ahmed Said | Abdel Twab, Raeesa | Al-Matrafi, Tahani | El-Medany, Jamila
Gastric ulcer is a worldwide disease. Helicobacter pylori is one of the most common chronic bacterial infections that induce chronic inflammation in the gastric mucosa, mediated by an array of pro-and inflammatory cytokines. The aim of this study was to investigate the possible therapeutic effects of Ginkgo biloba extract on gastric ulcer induced by ammonium hydroxide in rats and the potential underlying mechanisms. The study was done on 32 adult male Wistar albino rats, divided equally into 4 groups: normal control, gastric ulcer–induced group using 1 ml of 1% NH₄OH orally, ulcer control group; rats received 1% carboxymethyl cellulose daily for 14 days after induction of ulcer and treated rats received orally 200 mg/kg Ginkgo biloba once daily for 14 days after induction of ulcer. The study revealed administration of ammonia showed multiple gastric lesions; edema, hyperemia, hemorrhage, and ulcers with a significant increase in ulcer score, myeloperoxidase (MPO), and interleukin-1β (IL-1β) and a significant decrease in reduced glutathione (GSH), mucus amount, and gastric pH. After the administration of Ginkgo biloba, there was an improvement in gastric lesions, with a significant reduction of ulcer score, MPO, and IL-1β and a significant increase in GSH, mucus content, and gastric pH. Moreover, collagen types I and IV were gradually increased in the treated group.
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