Ginkgo Biloba Extract Treatment Research Articles

Ginkgo Biloba Extract Can Antagonize Subchronic Arsenite Exposure-Induced Hepatocyte Senescence by Inhibiting Oxidative Damage and Inflammation in Rats.

A growing body of evidence suggests that long-term arsenic exposure can induce liver injury. Our previous studies have demonstrated that liver injury occurs in arsenic-poisoning patients and arsenic-exposed rats. However, therapeutic targets are still unclear, and there is a lack of effective drugs. This study aimed to investigate the effects of sodium arsenite (arsenite) exposure on hepatocyte senescence and the intervention effect of ginkgo biloba extract in rats. In this study, 24 male Sprague-Dawley rats (weighing 180-200g) were randomized into three groups. The control group received a normal diet, and the arsenic-exposed group was given 10mg/L arsenite for 3months by free drinking along with a normal diet. The ginkgo biloba extract treatment group was consecutively administered EGb761 (10mg/kg, by gavage) for 1month following 2months of arsenite exposure. Our results showed that exposure to 10mg/L arsenite induced narrowing of the hepatic sinus space, enlargement of hepatocytes, and increased multinucleated hepatocytes and inflammatory cell infiltration in rat liver tissue compared with the normal control group. Moreover, 10mg/L arsenite also caused abnormal expression of inflammation-related indices (IL1-β, IL-6, TNF-α), oxidative damage-related indices (SOD, MDA, GPx), and senescence-related proteins (p16, p-p53, E2F1). EGb761 could effectively reduce the pathological damage of liver tissue and antagonize the abnormal expression of liver tissue inflammation and oxidative damage-related indices as well as cellular senescence-related proteins caused by arsenite exposure. Notably, EGb761 reduced the accumulation of arsenic in rat liver tissues. These results suggested that EGb761 could effectively alleviate subchronic arsenic exposure-induced senescence of hepatocytes, which may be achieved partially through inhibiting inflammation and oxidative damage in rats. This study may provide a new therapeutic target for arsenic-induced liver injury.

Effect of Ginkgo biloba Extract on Rehabilitation Treatment in Patients with Sepsis

Ginkgo biloba extract (GBE), as a natural herbal medicine, is thought to play a positive role in the rehabilitation of sepsis. This article aimed to explore the application effect of GBE in the rehabilitation treatment of patients with sepsis. Firstly, the system applicability test and chromatographic conditions were used to determine the content of GBE, the content was determined after solution preparation, and the precision of GBE was tested after sample collection to analyze the composition of GBE. 70 patients with sepsis admitted to hospital were retrospectively analyzed. The patients were divided into Controls (conventional treatment, n = 35) and GBE group (GBE treatment, n = 35). Through treatment, the levels of procalcitonin (PCT), interleukin-33 (IL-33), sequential organ failure assessment (SOFA), cTn1, CK-MB, IL-6, and TNF-α were compared between the two groups. H9C2 cells were cultured and treated. Normal group was cultured in DMEM medium having FBS without treatment. H2O2 group was treated with DMEM medium having FBS with 100 μmol/L H2O2 solution. H2O2 + GBE group was treated with 100 μmol/L H2O2 solution and 15 μmol/L ginkgetin solution. Western blot was used to detect the protein expression of Caspase-3, Caspase-6, Bax/Bcl-2, and FOXO1. It revealed the RSD of quercetin, kaempferol, and isorhamnetin in GBE was 0.51%, 0.92%, and 1.32%, respectively, less than 2.0%. Sample content determination indicated that the dried products met the requirements. PCT and SOFA, and the level of IL-33 in GBE group was clearly higher as against Controls, and cTnI, CK-MB, IL-6, and TNF-α in the Controls were clearly higher as against the GBE group (P < 0.05). In vitro cell experiments suggested that the Bax/Bcl-2 ratio and the expression of Caspase-3, Caspase-6, and FOXO1 proteins were gradually increased in Normal, H2O2, and H2O2 + GBE groups. The H2O2 group was clearly superior as against the Normal, and the H2O2 + GBE group was clearly superior as against the H2O2 group (P < 0.05). As against the Normal, the expressions of Caspase-3 and Caspase-6, and the ratio of Bax to Bcl-2 was clearly decreased in the H2O2 + GBE group (P < 0.05). In conclusion, GBE can promote the recovery process of patients by reducing inflammatory response, inhibiting oxidative stress, and improving immune function.

Ginkgo biloba extract ameliorates hyperglycaemia-induced enteric glial cell injury via regulation of the TLR2-related pathway.

Diabetic gastrointestinal dysfunction (DGD) is a common complication in diabetic patients, and enteric glial cells (EGCs) found in the gastrointestinal tract have been shown to play an essential role in gastrointestinal dysfunction. Thus, targeting EGCs may be helpful for the control of DGD. This study aimed to evaluate the protective effect of Ginkgo biloba extract (GBE) from G. biloba dropping pills against hyperglycaemic stress-induced EGCs injury and its underlying mechanism. In vitro, the protective effect of GBE on CRL-2690 cells was evaluated by MTT assay and TUNEL assay. The expression of related markers was evaluated by RNA sequencing and validated by using western blotting. In vivo, STZ-induced C57BL/6J WT mice were used as models to evaluate the effects of GBE on blood glucose, body weight, and EGCs' activity and relevant signalling pathways were validated by immunofluorescence. The results showed that GBE (25 μg/ml) treatment significantly attenuated hyperglycaemic stress-induced cytotoxicity and cell apoptosis in CRL-2690 cells, which was verified in an STZ-induced (100 mg/kg, 3 days) diabetic mouse model with continuous GBE administration (25/100 mg/kg/day, 6/12 weeks). Further mechanistic study based on transcriptomic data revealed that GBE exerted its beneficial effect by regulating immune-related pathways, and TLR2/BTK/NF-κB/IL-1α/IL-10 comprised the main targets of this drug. This study demonstrates the protective effect of GBE against hyperglycaemic stress-induced EGCs injury using both in vitro and in vivo models and further reveals that the effect was achieved by targeting TLR2 and its downstream molecules BTK/NF-κB/IL-1α/IL-10. This study may be helpful for expanding the clinical application of GBE in treating DGD.

Ginkgo biloba Extract Preventively Intervenes in Citrobacter Rodentium-Induced Colitis in Mice.

Inflammatory bowel disease (IBD) represents a highly recurrent gastrointestinal disorder and global public health issue. However, it lacks effective and safe strategies for its control. Although Ginkgo biloba extract (GBE) has been suggested to exhibit preventive and therapeutic activity for the control of IBD, whether its activity is associated with its ability to modulate intestinal microbiota remains to be addressed. To investigate the effect of GBE on controlling IBD, a Citrobacter Rodentium (CR)-induced mouse colitis model was used, and then histopathological examinations, biochemical assays, immunohistochemistry, and immunoblotting were performed to detect histological changes, cytokines, and tight junction (TJ) proteins in the intestine samples. We also studied 16s rRNA to detect changes in intestinal microbiota and used GC-MS to determine the microbiota-related metabolites short chain fatty acids (SCFAs). The results of our studies revealed that pre-treatment with GBE was sufficient for protecting the animals from CR-induced colitis. As a mechanism for GBE activity, GBE treatment was able to modulate the intestinal microbiota and increase the SCFAs capable of decreasing the pro-inflammatory factors and up-regulating the anti-inflammatory factors while elevating the intestinal-barrier-associated proteins to maintain the integrity of the intestines. Accordingly, our results led to a strong suggestion that GBE should be seriously considered in the preventive control of CR-induced colitis and in the development of effective and safe therapeutic strategies for controlling IBD.

Ginkgo biloba extract protects against diabetic cardiomyopathy by restoring autophagy via adenosine monophosphate-activated protein kinase/mammalian target of the rapamycin pathway modulation.

Studies demonstrated that Ginkgo biloba extract (GBE) played a cardioprotective role in diabetic conditions. Impaired autophagy is one of the mechanisms underlying diabetic cardiomyopathy (DCM). The effect of GBE on autophagy has been observed in several diseases; however, whether GBE can ameliorate DCM by regulating autophagy remains unclear. Here, we investigated the effect of GBE on DCM and the potential mechanisms regarding autophagy using a streptozotocin (STZ)-induced diabetic rat model and a high-glucose (HG)-stimulated H9C2 cell model. We demonstrated that GBE attenuated metabolic disturbances, improved cardiac function, and reduced myocardial pathological changes in diabetic rats. Impaired autophagy as well as dysregulation of the adenosine monophosphate-activated protein kinase/ mammalian target of the rapamycin (AMPK/mTOR) signaling pathway were observed in diabetic hearts, as evidenced by the reduced conversion of LC3B-I to LC3B-II along with excessive p62 accumulation, decreased AMPK phosphorylation, and increased mTOR phosphorylation, which could be reversed by GBE treatment. In vitro, GBE reduced the apoptosis induced by HG in H9C2 cells by activating AMPK and inhibiting mTOR to restore autophagy. However, this effect was inhibited by the AMPK inhibitor Compound C. In conclusion, the ameliorative effect of GBE on DCM might be dependent on the restoration of autophagy through modulation of the AMPK/mTOR pathway.

Inflammatory mechanisms of Ginkgo Biloba extract in improving memory functions through lncRNA-COX2/NF-κB pathway in mice with status epilepticus.

This study was to explore whether Ginkgo biloba extract (GBE) improve memory impairment by alleviating neuroinflammation signaling in mice with status epilepticus. The status epilepticus (SE) mice model was established by pilocarpine and treated with 100 mg / kg of GBE for 14 days. Spontaneous alternation of Y-maze and new object recognition were used to explore memory impairment. To examine glial cell activation, we performed immunohistochemistry and immunofluorescence staining. The activation of NF-κB signaling and the expression level of lncRNA-COX2 were detected by Western blot and qRT-PCR, respectively. Adeno-associated virus lncRNA-COX2 was injected into mice for overexpression of lncRNA-COX2. After GBE treatment, the spontaneous alternation rate and the recognition coefficient in SE mice were both increased. Moreover, activation of glial cells, NF-κB signaling and lncRNA-COX2 were significantly decreased in SE mice. In the GBE-treated SE mice with lncRNA-COX2 overexpression, NF-κB signaling was up-regulated again; the reduced level of inflammation factors was reversed; the GBE-rescued spontaneous alternation rate of Y-maze was eliminated. Our results suggested that GBE reduces the hippocampal inflammation by down-regulating lncRNA-COX2 / NF-κB signaling in the SE mice, leading to the decrease of neuronal damage and the improvement of memory functions.

Extract of Ginkgo biloba leaves attenuates neurotoxic damages in rats and SH-SY5Y cells exposed to a high level of fluoride

BackgroundPotential protection against the neurotoxic damages of high levels of fluoride on rats and SH-SY5Y cells by extract of Ginkgo biloba leaves, as well as underlying mechanisms, were examined. MethodsThe rats were divided randomly into 4 groups, i.e., control, treatment with the extract (100 mg/kg body weight, gavage once daily), treatment with fluoride (50 ppm F- in drinking water) and combined treatment with both; SH-SY5Y cells exposed to fluoride and fluoride in combination with the extract or 4-Amino-1,8-naphthalimide (4-ANI), an inhibitor of poly (ADP-ribose) polymerase-1 (PARP-1). Spatial learning and memory in the rats were assessed employing Morris water maze test; the contents of fluoride in brains and urine by fluoride ion-selective electrode; cytotoxicity of fluoride was by CCK-8 kit; the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and the content of malondialdehyde (MDA) by appropriate kits; the level of 8-hydroxydeoxyguanosine (8-OHdG) was by ELISA; the content of ROS and frequency of apoptosis by flow cytometry; the expressions of phospho-histone H2A.X(Ser139), PARP-1, poly (ADP-ribose) (PAR) and Sirtuin-1 (SIRT1) by Western blotting or immunofluorescence. ResultsThe rats with prolong treatment of fluoride exhibited dental fluorosis, the increased contents of fluoride in brains and urine and the declined ability of learning and memory. In the hippocampus of the rats and SH-SY5Y cells exposed to fluoride, the levels of ROS, MDA, apoptosis, 8-OHdG and the protein expressions of histone H2A.X(Ser139), PARP-1 and PAR were all elevated; the activities of SOD and GSH-Px and the protein expression of SIRT1 reduced. Interestingly, the treatment of Ginkgo biloba extract attenuated these neurotoxic effects on rats and SH-SY5Y cells exposed to fluoride and the treatment of 4-ANI produced a neuroprotective effect against fluoride exposure. ConclusionGinkgo biloba extract attenuated neurotoxic damages induced by fluoride exposure to rats and SH-SY5Y cells and the underlying mechanism might involve the inhibition of PARP-1 and the promotion of SIRT1.

Ginkgo biloba Extract Attenuates Light-Induced Photoreceptor Degeneration by Modulating CAV-1-Redoxosome Signaling.

The clinical potential of Ginkgo biloba extract (GBE) in the prevention and/or treatment of retinal degenerative diseases has been widely explored; however, the underlying molecular mechanism is poorly understood. Photoreceptor degeneration is the hallmark of retinal degenerative diseases and leads to vision impairment or loss. In this study, the effect of GBE against white light (WL) illumination-induced photoreceptor degeneration was investigated, as well as its underlying mechanism. To evaluate the in vitro activity of GBE, analysis of cell viability, cell apoptosis, oxidative stress, NOX (NADH oxidase) activity and mitochondrial membrane potential (MMP), as well as Western blotting and transcriptome sequencing and analysis, were conducted. To evaluate the in vivo activity of GBE, HE staining, electroretinography (ERG), Terminal-deoxynucleoitidyl transferase (TdT)-mediated nick end labeling (TUNEL) assay and immunofluorescence analysis were conducted. Our study showed that GBE treatment significantly attenuated WL illumination-induced oxidative damage in photoreceptor 661W cells—a finding that was also verified in C57BL/6J mice. Further molecular study revealed that WL illumination downregulated caveolin-1 (CAV-1) expression, interrupted CAV-1-NOX2 interaction, re-located NOX2 from the cell membrane to the cytoplasm and induced the formation of redoxosomes, which led to cell death. However, these cytotoxic events were significantly alleviated by GBE treatment. Interestingly, CAV-1 overexpression showed a consistent protective effect with GBE, while CAV-1 silencing impacted the protective effect of GBE against WL illumination-induced oxidative damage in in vitro and in vivo models. Thus, GBE was identified to prevent photoreceptor cell death due to CAV-1-dependent redoxosome activation, oxidative stress and mitochondrial dysfunction resulting from WL illumination. Overall, our study reveals the protective effect of GBE on photoreceptors against WL illumination-induced oxidative damage in in vitro and in vivo models, which effect is mediated through the modulation of CAV-1-redoxosome signaling. Our findings contribute to better understanding the therapeutic effect of GBE in preventing photoreceptor degeneration in retinal degenerative diseases, and GBE may become a novel therapeutic agent that is effective in reducing the morbidity of these diseases.

The Clinical Efficacy and Possible Mechanism of Combination Treatment of Cerebral Ischemic Stroke with Ginkgo Biloba Extract and Low-Frequency Repetitive Transcranial Magnetic Stimulation

To study the effect of the combination treatment of ginkgo biloba extract and low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) on the oxidative stress and brain neurotransmitters of patients who had cerebral ischemic stroke (CIS). A retrospective analysis was conducted, and 93 CIS patients admitted to the Sichuan Academy of Medical Sciences/Sichuan Provincial People's Hospital from January 2018 to January 2020 were included in the study. They were divided into three groups, the regular treatment group (31 cases), the LF-rTMS group (31 cases), and the combination treatment group (31 cases). Patients in the regular treatment group were given the conventional drug therapy and exercise regimen. The LF-rTMS group received LF-rTMS therapy (for 20-30 min each time, 1 time/d and 5 times/week) in addition to the treatment given to the regular treatment group. The combination treatment group was given ginkgo biloba extract (intravenous drips, once per day) in addition to the treatment given to the LF-rTMS group. The treatment was given continuously for 4 weeks and comparison was made at the end of the 4-week treatment regarding the clinical efficacy, oxidative stress response, cerebral oxygen metabolism, and brain neurotransmitter as shown by the three groups. The treatment efficacy in the combination treatment group (96.77%) was higher than those of the LF-rTMS group (80.65%) and the regular treatment group (54.84%). The LF-rTMS group showed higher treatment efficacy than that of the regular group. The serum superoxide dismutase (SOD) of the combination treatment group was higher than that of the LF-rTMS group and that of the routine group, while the malondialdehyde (MDA) and endothelin-1 (ET-1) of the combination treatment group were lower than those of the LF-rTMS group and the regular treatment group ( P<0.05). The serum SOD of the LF-rTMS group was higher than that of the regular treatment group, while the MDA and ET-1 of the group was lower than those of the regular treatment group ( P<0.05). The arterial oxygen content (CaO 2), arterio-venous oxygen content difference (Ca-vO 2) and cerebral extraction rate of oxygen (CERO 2) in the combination treatment group were lower than those of the LF-rTMS group and the regular treatment group ( P<0.05). The levels of these three indicators of the LF-rTMS group were lower than those of the regular treatment group ( P<0.05). EEG frequencies of gamma-aminobutyric acid (GABA), 5-hydroxytryptamine (5-HT) and dopamine (DA) of the combination treatment group were higher than those of the LF-rTMS group and the regular treatment group, while the acetylcholine (Ach) EEG frequency of the combination treatment group was lower than that of the LF-rTMS group and regular treatment group ( P<0.05). The LF-rTMS group showed higher GABA, 5-HT and DA EEG frequencies than those of the regular treatment group, while the Ach EEG frequency of the group was lower than that of the regular treatment group ( P<0.05). All the patients were followed up for 6 months, and recurrence rate was lower in the combination treatment group (3.23%) than that of the LF-rTMS group (19.35%) and the regular treatment group (25.81%) ( P<0.05). The combination treatment of ginkgo biloba extract and LF-rTMS helped to improve the clinical outcome of CIS patients, which may be related to the inhibition of oxidative stress, improvement in cerebral oxygen metabolism, and regulation of brain neurotransmitter.

Ginkgo biloba Extract (GbE) Restores Serotonin and Leptin Receptor Levels and Plays an Antioxidative Role in the Hippocampus of Ovariectomized Rats.

Since Ginkgo biloba extract (GbE) was reported to improve the hypothalamic serotonergic system of ovariectomized (OVX) rats, the present study aimed to verify the GbE effects on hippocampal oxidative stress, inflammation, and levels of the serotonin transporter (5-HTT), and both the serotonin (5-HT1A, 5-HT1B) and leptin receptors of OVX rats. Two-month-old female Wistar rats had their ovaries surgically removed (OVX) or not (SHAM). After 60days, OVX rats were gavaged daily with GbE 500mgkg-1 (OVX+GbE), while SHAM and OVX groups received saline 0.9% (vehicle) for 14days. Rats were then euthanized, and hippocampi were collected. Both 5-HT1A and 5-HT1B levels were significantly reduced in OVX rats compared to SHAM rats, while 5-HT1A was higher in OVX+GbE rats in comparison to OVX rats. Similarly, LepR levels were increased in OVX+GbE rats compared to OVX rats, reaching similar levels to SHAM rats. Superoxide dismutase activity increased in OVX rats in relation to SHAM rats, which was restored to SHAM levels by GbE treatment. Additionally, GbE significantly increased the glutathione peroxidase activity in comparison to the SHAM group. No differences were observed either in catalase activity or in the levels of 5-HTT, PKCα, TLR-4, NF-κBp50, ERK, and CREB. In summary, our results show a potential effect of GbE on hippocampal pathways involved in feeding behavior, and thus, they suggest that GbE activity might improve menopausal-related hippocampal disorders, offering an alternative therapeutic tool particularly for women to whom hormone replacement therapy may be contraindicated.

Ginkgo biloba extract (GbE) attenuates obesity and anxious/depressive-like behaviours induced by ovariectomy

While several pieces of evidence link obesity and mood disorders in menopause, the mechanisms involved are not yet fully understood. We have previously demonstrated that Ginkgo biloba extract (GbE) both attenuated diet-induced obesity of male rats and restored serotonin-induced hypophagia in ovariectomized female rats. The present study aimed at exploring whether GbE treatment ameliorates ovariectomy-related obesity and anxious/depressive-like behaviours. Wistar female rats were either ovariectomized (OVX) or sham-operated (Sham). After 2 months, either 500 mg/kg of GbE or vehicle were administered daily by gavage for 14 days. Anxious/depressive-like behaviours were assessed by the Elevated Plus Maze and the Forced Swim Tests, respectively. Ovariectomy caused high visceral adiposity, hyperleptinemia, and hypercholesterolemia, and increased the anxiety index (p = 0.048 vs. Sham + GbE) while it decreased the latency to immobility (p = 0.004 vs. Sham). GbE treatment in OVX rats improved body composition, adiponectin levels and blood lipid profile. It also reduced the anxiety index (p = 0.004) and increased the latency to immobility (p = 0.003) of OVX rats. Linear regression analysis demonstrated that leptin (p = 0.047) and total cholesterol levels (p = 0.022) were associated with anxious-like behaviours while body adiposity (p = 0.00005) was strongly associated with depressive-like behaviours. The results showed that GbE therapy was effective in attenuating the deleterious effects of ovariectomy on body composition, lipid profile, and anxious/depressive-like behaviours. Further studies are warranted to better understand the therapeutic potential of GbE in menopause.

GBE attenuates arsenite-induced hepatotoxicity by regulating E2F1-autophagy-E2F7a pathway and restoring lysosomal activity.

Arsenic is an environmental toxicant.Itsoverdose can cause liver damage. Autophagy has been reported to be involved in arsenite (iAs3+ ) cytotoxicity and plays a dual role in cell proliferation and cell death. However, the effect and molecular regulative mechanisms of iAs3+ on autophagy in hepatocytes remains largely unknown. Here, we found that iAs3+ exposure lead to hepatotoxicity by inducing autophagosome and autolysosome accumulation. On the one hand, iAs3+ promoted autophagosome synthesis by inhibiting E2F1/mTOR pathway in L-02 human hepatocytes. On the other, iAs3+ blocked autophagosome degradation partially via suppressing the expression of INPP5E and Rab7 as well as impairing lysosomal activity. More importantly, autophagosome and autolysosome accumulation induced by iAs3+ increased the protein level of E2F7a, which could further inhibit cell viability and induce apoptosis of L-02 cells. The treatment of Ginkgo biloba extract (GBE) effectively reduced autophagosome and autolysosome accumulation and thus alleviated iAs3+ -induced hepatotoxicity. Moreover, GBE could also protect lysosomal activity, promote the phosphorylation level of E2F1 (Ser364 and Thr433) and Rb (Ser780) as well as suppress the protein level of E2F7a in iAs3+ -treated L-02 cells. Taken together, our data suggested that autophagosome and autophagolysosome accumulation playa critical role for iAs3+ -induced hepatotoxicity, and GBE is a promising candidate for intervening iAs3+ induced liver damage by regulating E2F1-autophagy-E2F7a pathway and restoring lysosomal activity.

Potential antiosteoporotic effect of ginkgo biloba extract via regulation of SIRT1-NF-kB signaling pathway

ObjectiveOsteoporosis is bone disorder that happens when too much bone is damaged by the body, causing too little bone or both. As a consequence, bones are brittle and may crack from dropping or sneezing or small bumps in extreme situations. Ginkgo biloba is a Traditional Chinese Medicine (TCM) and commonly used for the treatment of various bone related disease. The current experimental study aimed to scrutinize the anti-osteoporosis effect of Ginkgo biloba and explore the possible mechanism of action. MethodsThe rats were divided into following groups; Control, Osteoporosis, osteoporosis received ginkgo biloba (25, 50 and 100 mg/kg) and rats were received the treatment after the surgery for 8 weeks. Bone parameters, osteocalcin (OC), alkaline phosphatase (ALP), calcium (Ca), phosphorus (P) and cytokines were estimated. The expression of sirtuin 1 (SIRT1) and nuclear factor kappa B (NF‑κB) were estimated. ResultsDose dependently treatment of ginkgo biloba extract significantly altered the bone parameters such as increase the number of trabecular bone, trabecular bone thickness, connectivity density, ration of BV/TV and decrease the trabecular separation. Ginkgo biloba extract decreased the serum level of ALP, OC, Ca and P at dose dependent manner. ginkgo biloba extract decreased the cytokines at dose dependent manner. Ginkgo biloba extract also reduced the expression of SIRT1 and NF-kB. ConclusionWe can conclude that ginkgo biloba extract showed the anti-osteoporosis effect via activation of SIRT1-NF-kB pathway.

Oral Supplements of Ginkgo biloba Extract Alleviate Neuroinflammation, Oxidative Impairments and Neurotoxicity in Rotenone-Induced Parkinsonian Rats.

Ginkgo biloba extract (GbE) is known to contain several bioactive compounds and exhibits free radical scavenging activity. Parkinson's Disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic neurons and is associated with oxidative stress, neuroinflammation and apoptosis. The current study aimed to investigate the neuroprotective effect of GbE in a rat model of PD induced by rotenone (ROT; a neurotoxin). Twenty-four male albino rats were randomly divided into four groups of six rats each: normal control, GbE treated, toxin control (ROT treated) and GbE+ROT group. Oral administration of ROT (2.5 mg/kg b.w.) for 50 days caused an increased generation of lipid peroxidation products and significant depletion of reduced glutathione, total thiol content and activities of enzymatic antioxidants, i.e., superoxide dismutase and glutathione peroxidase in the brains of treated rats. Furthermore, ROT caused an elevation in acetylcholinesterase, interleukin-1β, interleukin- 6 and tumor necrosis factor-α and a significant reduction in dopamine in the stratum and substantia nigra. Immunohistochemical results illustrated that ROT treatment reduced the expression of tyrosine hydroxylase (TH). GbE treatment (150 mg/kg b.w./day) significantly reduced the elevated oxidative stress markers and proinflammatory cytokines and restored the reduced antioxidant enzyme activities, DA level and TH expression. These results were confirmed by histological observations that clearly indicated a neuroprotective effect of GbE against ROT-induced PD. GbE mitigated ROT-induced PD via the inhibition of free-radical production, scavenging of ROS, and antioxidant enhancement.

Ginkgobiloba extract protects diabetic rats against cerebral ischemia‑reperfusion injury by suppressing oxidative stress and upregulating the expression of glutamate transporter 1.

The current study aimed to evaluate the neuroprotective effect of Ginkgo biloba extract (GbE) on the progression of acute cerebral ischemia-reperfusion injury in diabetic rats, and to determine the molecular mechanism associated with this effect. Streptozotocin (STZ) induced diabetic rats were pretreated with GbE (50, 100 and 200 mg/kg/day; intragastric) for 3 weeks. During this period, body weight changes and fasting blood glucose levels were assessed each week. Following pretreatment, rats were subjected to suture occlusion of the middle cerebral artery for 30 min, which was followed by 24 h of reperfusion. Neurological deficits were subsequently evaluated at 2 and 24 h following reperfusion. Rats were sacrificed after 24 h reperfusion, and infarct volume and S100B content were measured to evaluate the neuroprotective effect of GbE. The results of the present study demonstrated that GbE pretreatment improved neurological scores, and reduced cerebral infarct volume and S100B content. Oxidative stress markers, including glutathione (GSH) and superoxide dismutase (SOD) were increased, and malondialdehyde (MDA) contents were reduced following GbE treatment. The levels of p-Akt, p-mTOR and glutamate transporter 1 (GLT1) were observed to be increased in GbE-pretreated rats. These results indicated that GbE pretreatment may serve a protective role against cerebral ischemia-reperfusion injury in diabetic rats by inhibiting oxidative stress reaction, upregulating the expression of Akt/mTOR and promoting GLT1 expression. In conclusion, the current study revealed the protective role and molecular mechanisms of GbE in diabetic rats with cerebral ischemia-reperfusion injury, and may provide novel insight into the future clinical treatment of this condition.

Ginkgo biloba ameliorates fluoride toxicity in rats by altering histopathology, serum enzymes of heme metabolism and oxidative stress without affecting brain mGluR5 gene

Background: To evaluate the therapeutic potential of Ginkgo biloba extract (GBE) in experimental model of fluorosis. Objectives: To study the protective effect of GBE in fluoride toxicity by assessment of oxidative stress, serum biochemical parameters, acetylcholinesterase (AChE) activity, histopathology and brain mGluR5 gene expression. Materials and Methods: Fifteen adult male Wistar rats were randomly assigned to 5 groups (n = 3 rats in each group). Group 1 (control) received water, Groups 2–5 were treated with 100 ppm of sodium fluoride for 30 days, while the Groups 3, 4 and 5 were GBE treated with 50 mg/kg, 100 mg/kg and 200 mg/kg body weight for 15 days, after sodium fluoride treatment for 30 days. Results: Elevated serum delta aminolevulinic acid dehydratase and delta aminolevulinic acid synthatase levels in fluoride intoxicated rats were ameliorated by various doses of GBE treatment. Elevated serum glutathione and decreased oxidized gluatathione levels observed in fluoride intoxicated rats were also ameliorated by GBE treatment but effectively at 100 mg/kg dose. Reduced AChE activity of hippocampus in fluoride-induced toxicity was reverted by 50 mg/kg of GBE whereas other doses (100 and 200 mg/kg) caused significant inhibition of AChE activity in comparison with fluoride group. Fluoride group rats showed significant reduction of mGluR5 gene expression levels whereas in all GBE treatment groups those changes Were not significantly reverted. GBE treatment to fluoride intoxicated rats almost reverted the degenerative changes in liver and kidney caused by fluorosis. Conclusion: The present study concluded beneficial effects of GBE in experimental model of fluorosis.

Ginkgo biloba Induces Thrombomodulin Expression and Tissue-Type Plasminogen Activator Secretion via the Activation of Krüppel-Like Factor 2 within Endothelial Cells.

The effects of thrombo-prevention, such as antiplatelet and anticoagulant activity, have been reported with the usage of Ginkgo biloba extract (GbE); however, the detailed mechanism has not yet been fully investigated, especially the role of Krüppel-like factor 2 (KLF2). This study aimed to investigate whether GbE can activate KLF2 and then induce thrombomodulin (TM) and tissue-type plasminogen activator (t-PA) secretion to enhance the effects of thrombo-prevention. Different concentrations of GbE were incubated with human umbilical vein endothelial cells (HUVECs) to evaluate its effect on endothelial cells. We found that KLF2 expression is correlated to the risk of atherosclerosis and venous thromboembolism in clinical practice. In the HUVEC cell model, GbE stimulated the expression of KLF2 in a dose-dependent manner. Moreover, TM and t-PA secretion increased when the cells were cultured with GbE.Both the expressions and activities of TM and t-PA in the GbE-treated cells declined after KLF2 was blocked by shKLF2. In sum, with GbE treatment, KLF2 expression in human endothelial cells was significantly activated, which in turn induced an increase in the protein expression and activity of TM and t-PA.After shRNA inhibited the KLF2 expression, GbE stopped inducing the expression and activity of TM and t-PA.These findings suggest that GbE exerts an antithrombotic effect on endothelial cells by increasing the TM expression and t-PA secretion; further, KLF2 is a key factor in this mechanism.

Ginkgo biloba extract attenuates the disruption of pro-and anti-inflammatory T-cell balance in peripheral blood of arsenicosis patients.

Endemic arsenicosis is a public health problem that affects thousands of people worldwide. However, the biological mechanism involved is not well characterized, and there is no specific treatment. Exposure to arsenic may be associated with immune-related problems. In the present work, we performed an investigation to determine whether the Th17/Treg balance was abnormal in peripheral blood mononuclear cells (PBMCs) of patients with arsenicosis caused by burning coal. Furthermore, we investigated the effect of Ginkgo biloba extract (GBE) on the Th17/Treg imbalance in patients with arsenicosis. In this trial, 81 arsenicosis patients and 37 controls were enrolled. The numbers of Th17 and Treg cells, as well as related transcription factors and serum cytokines, were determined at the beginning and end of the study. Patients with arsenicosis exhibited higher levels of Th17 cells, Th17-related cytokines (IL-17A and IL-6), and the transcription factor RORγt. There were lower levels of Treg cells, a Treg-related cytokine (IL-10), and the transcription factor Foxp3 as compared with controls. There was a positive correlation between the levels of Th17 cells and IL-17A and the levels of arsenic in hair. Arsenicosis patients were randomly assigned to a GBE treatment group or a placebo group. After 3 months of follow-up, 74 patients completed the study (39 cases in the GBE group and 35 in the placebo group). Administration of GBE to patient upregulated the numbers of Treg cells and the level of IL-10 and downregulated the numbers of Th17 cells and the levels of cytokines associated with Th17 cells. The mRNA levels of Foxp3 and RORγt were increased and decreased, respectively. These results indicated that exposure to arsenic is associated with immune-related problems. The present investigation describes a previously unknown mechanism showing that an imbalance of pro- and anti-inflammatory T cells is involved in the pathogenesis of arsenicosis and that a GBE exerts effects on arsenicosis through regulation of the pro- and anti-inflammatory T cell balance.

Ginkgo biloba extract increases neurite outgrowth and activates the Akt/mTOR pathway.

Standardized Ginkgo biloba extract (GBE) has demonstrated efficacy in the cognitive functional neuropsychiatric symptoms of patients with Alzheimer's disease (AD). With regard to its underlying molecular mode of action, first evidence was provided that GBE was able to modulate neuronal outgrowth in vitro, but the mechanisms underlying GBE effects on neuroplasticity remain unclear. In this study, we investigated the effect of GBE on neurite outgrowth using SH-SY5Y neuroblastoma cells in a 2D and 3D surface culture. The effects of the GBE LI1370 on neuroplasticity and neurite outgrowth were compared to those of nerve growth factor (NGF, 50 ng/ml) which was used as a positive control. We evaluated several parameters of neurite outgrowth such as the neurite number, total neurite length and extend of branching. Our findings showed that GBE (10 and 100 μg/ml) significantly increased neurite outgrowth in the 2D as well as 3D culture model after 3 days of treatment with a comparable effect than that NGF. The use of the 3D cell culture allowed us to better reproduce the in vivo neuronal microenvironment for the evaluation the neurite formation after GBE treatment. In addition, we assessed the effects of GBE on the Akt/mTOR pathway, which is known to promote neuroplasticity induced by nerve growth factors. We showed that GBE treatment induced an increase of phosphorylated IGF1R (Tyr1135/Tyr1136), Akt (Ser473), TSC2 (Ser939), mTOR (Ser2448), PTEN (Ser380) and GSK3β (Ser9). Together, these findings indicate that GBE promotes neurite growth and activates the PI3K/Akt/mTOR pathway suggesting that this plant extract supports neuronal plasticity.

Activation of heme oxygenase-1 by Ginkgo biloba extract differentially modulates endothelial and smooth muscle-like progenitor cells for vascular repair

Vascular progenitors such as endothelial progenitor cells (EPCs) and smooth muscle-like progenitor cells (SMPCs) may play different roles in vascular repair. Ginkgo biloba extract (GBE) is an exogenous activator of heme oxygenase (HO)-1, which has been suggested to improve vascular repair; however, the detailed mechanisms have yet to be elucidated. This study aimed to investigate whether GBE can modulate different vascular progenitor cells by activating HO-1 for vascular repair. A bone marrow transplantation mouse model was used to evaluate the in vivo effects of GBE treatment on wire-injury induced neointimal hyperplasia, which is representative of impaired vascular repair. On day 14 of GBE treatment, the mice were subjected to wire injury of the femoral artery to identify vascular reendothelialization. Compared to the mice without treatment, neointimal hyperplasia was reduced in the mice that received GBE treatment for 28 days in a dose-dependent manner. Furthermore, GBE treatment increased bone marrow-derived EPCs, accelerated endothelial recovery, and reduced the number of SMPCs attached to vascular injury sites. The effects of GBE treatment on neointimal hyperplasia could be abolished by co-treatment with zinc protoporphyrin IX, an HO-1 inhibitor, suggesting the in vivo role of HO-1. In this in vitro study, treatment with GBE activated human early and late EPCs and suppressed SMPC migration. These effects were abolished by HO-1 siRNA and an HO-1 inhibitor. Furthermore, GBE induced the expression of HO-1 by activating PI3K/Akt/eNOS signaling in human late EPCs and via p38 pathways in SMPCs, suggesting that GBE can induce HO-1 in vitro through different molecular mechanisms in different vascular progenitor cells. Accordingly, GBE could activate early and late EPCs, suppress the migration of SMPCs, and improve in vivo vascular repair after mechanical injury by activating HO-1, suggesting the potential role of pharmacological HO-1 activators, such as GBE, for vascular protection in atherosclerotic diseases.