Treatment with Ginkgo biloba supplement modulates oxidative disturbances, inflammation and vascular functions in oxygen deprived hypothyroid mice: Involvement of endothelin-1/NO signaling pathways.

A double-hit biological alteration involving exposure to oxygen deprivation in hypothyroid condition may exacerbate cellular oxidative and inflammatory disturbances comparative to a one-hit biological exposure. This study investigated the therapeutic effect of Ginkgo biloba as cardioprotective against aortic oxido-inflammatory disturbances following oxygen deprivation in hypothyroid mice. Male Swiss mice were partitioned into 5 groups (n = 6) for hypothyroidism (Carbimazole 1.2 mg/kg) and hypoxia induction. Group 1 (normal control), group 2 (hypoxic stress control), group 3 (hypoxic and hypothyroid stress), group 4 (hypoxic and hypothyroid stress and Ginkgo biloba 20 mg/kg; p.o) and group 5 (hypoxic and hypothyroid stress and Levothyroxine 10 µg/kg; p.o) for 14 days. Thereafter, serum and aorta was collected for biochemical evaluation. GBS did not up-regulate the serum thyroid hormone imbalances (tri-iodothyronine (T3), thyroxin (T4)) but maintains the TSH levels. The blood glucose level was reduced with decrease oxidative stress and inflammatory mediators in the serum/aorta indicated by inhibited redox status following treatment with GBS. Moreover, endothelin-1/nitric oxide signaling pathways were markedly regulated in the aorta. Conclusively, GBS acts as a therapeutic agent and may be consider as a potential vasodilator candidate in the management and control of hypoxic stress in hypothyroid condition. PRACTICAL APPLICATIONS: Treatment with Gingko biloba supplement abated endothelial abnormalities via elevation of nitric oxide release and suppression of endothelin activity in hypothyroid mice exposed to hypoxic hypoxia. The activity of myeloperoxidase enzyme and redo-inflammatory status was downregulated following treatment with Gingko biloba supplement in hypothyroid mice exposed to hypoxic hypoxia. Treatment with Gingko biloba supplement modulates hypothalamic-pituitary-adrenal (HPA) axis by inhibiting corticosterone release in hypothyroid mice exposed to hypoxic hypoxia.

The Anti-Parkinson Potential of Gingko biloba-Supplement Mitigates Cortico-Cerebellar Degeneration and Neuropathobiological Alterations via Inflammatory and Apoptotic Mediators in Mice.

Activation of nuclear factor erythroid 2 related factor 2 (Nrf2) associated with the suppression of various oxido-inflammatory pathways and the controller of several gene expressions involving "antioxidant response elements" (AREs) in their promoters to mediate and restores homeostatic functions is now considered as one of the main switch regulating the immune response, and it is also now involved in inflammatory cascade in PD. Whether therapeutic approach using Ginkgo biloba would have significant protective effects against cortico-cerebellar dopaminergic degeneration in rotenone-induced mice remains unknown. In this present study, we studied the therapeutic effects of Ginkgo biloba-supplement (Gb-S) administration in cortico-cerebellar dopaminergic degeneration. The results revealed that treatment with Gb-S suppresses cognitive decline and neuromuscular incompetence in the mice, abated tyrosine hydroxylase depletion and synucleinopathy development in the cortico-cerebellar neurons of the mice before and after rotenone induction. However, our data further shows increase Nrf2 immunoexpression with decrease oxido-nitrergic and neuroinflammatory release, increase cholinergic enzyme activity and downregulated executioner caspase-3 that may mediate cortico-cerebellar apoptosis. Also, the loss of cortico-cerebellar neurons was attenuated, marked by increase in dendritic spine length and width with numerous viable neurons. Overall findings suggest that Gb-S could be a potential pharmacotherapeutic candidate providing a strong protection for cortico-cerebellar neurocellular substances and against Parkinsonism-like non-motor and motor symptoms.

Lead acetate induces hippocampal pyramidal neuron degeneration in mice via up-regulation of executioner caspase-3, oxido-inflammatory stress expression and decreased BDNF and cholinergic activity: Reversal effects of Gingko biloba supplement.

PURPOSE: It has been hypothesized that compounds with strong anti-oxidant activity might mitigate lead-induced neurotoxicity that resulted to neuronal degeneration.Ginkgo biloba supplement (GB-S) is a neuroactive supplement which has been reported to demonstrate neuroprotective effects. In this study, we investigated the reversal effect and the underlying mechanism of GB-S following lead-induced neurotoxicity in mice. METHODS: Male Swiss mice (n = 8) were pre-treated with lead acetate (100 mg/kg) for 30 min before GB-S (10 mg/kg and 20 mg/kg) or Ethylenediaminetetraacetic acid (EDTA) (50 mg/kg) intraperitoneally for 14 consecutive days. Memory impairment symptoms were evaluated on day 13 and 14 using Y-maze and Novel object recognition test (NORT) respectively. Thereafter, spectrophotometry, ELISA, immunohistochemistry and histomorphormetry were used to estimate the degree and expression of biomarkers of neuronal inflammation: oxido-inflammatory stress, apoptosis and degeneration in the hippocampus (HC). RESULTS: Lead acetate treatment significantly (p < 0.05) induced neurobehavioral impairment which was reversed by GB-S as evident in increased percentage alternation and discrimination index. GB-S significantly (p < 0.05) reduced lipid peroxidation and nitrite level, inhibited TNF-α and acetylcholinesterase activity and improved glutathione, catalase and superoxide dismutase activity in the HC. Moreover, GB-S inhibited hippocampal apoptosis via elevated expression of caspase-3 with marked increase level of brain derived neurotrophic factor (BDNF). Also, the histomorphormetric study showed that GB-S rescued death of pyramidal neurons (CA3) in the HC. CONCLUSION: Our findings however suggest that GB-S decreased memory impairment progression induced by lead acetate via mechanisms connected to inhibition of oxido-inflammatory stress mediators, restrained acetylcholinesterase activity, up-regulated BDNF/Caspase-3 expression and suppression of hippocampal pyramidal neuron degeneration in mice.