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Problem statement:Recent findings demonstrated the crucial role of oxidative stress on the pathophysiology of Alzheimer's Disease (AD). Antioxidant intake is beneficial to delay or inhibit the progression of this disease. Quercetin, a bioflavonoid in fruits and vegetables, has a powerful antioxidant activity both in vitro and in vivo. Claims that quercetin has many biological activities. However, quercetin is rapidly metabolized and limited ability to cross the blood-brain-barrier are obstacles to its use for treatment of AD. Liposomes have been used as an effective delivery system to the brain. Advantages associated with the nasal administration over oral route include higher bioavailability due to no first pass hepatic metabolism and rapid absorption leading to shorter time to onset of effect. Based on this information, the effects of quercetin liposomes via nasal route on improving cognitive behavior and biochemical markers of oxidative stress, Superoxide Dismutase (SOD), catalase, glutathione and Malondialdehyde (MDA) in the hippocampus in animal model of AD were investigated. Approach: Male Wistar rats were pretreated with quercetin liposomes, containing 0.5 mg of quercetin in 20 µL (dose = 20 µg), via intranasal route once daily continually for 2 weeks before and 1 week after AF64A administration. Learning and memory was evaluated using the Morris water maze test at 7 days after the AF64A administration and then the rats were sacrificed for determining the content of MDA and the activities of SOD, catalase and glutathione in the hippocampus. Results: Quercetin liposomes via nasal administration significantly improved memory impairment by inhibiting the oxidative damage in hippocampus. The possible underlying mechanisms might be partly associated with the decrease the level of MDA whereas increase the activity of SOD, catalase and glutathione. Conclusion: Our studies demonstrated that quercetin liposomes via nasal administration may have a therapeutic importance in the clinical management of AD.

Age-related decline in erectile function is a noted phenomenon worldwide. A variety of medicinal plants have been identified as having strong aphrodisiac properties along with the ability to improve erectile functioning. Kaempferia Parviflora (KP) has famous as a Thai Viagra and use it to increase male impotency. However, there is limited scientific evidence regarding the efficacy of this herb on this issue in aging healthy men. This study therefore investigated the effect of KP extract administration on erectile response of male elderly volunteers. Total 45 male healthy elderly volunteers will be divided into 3 separated groups including placebo and the different doses of ethanolic extracts of KP (25 and 90 mg) once daily at a period of 2 months. The erectile function tests including the response latency time to visual erotic stimuli, size and length of penis both in flaccid and erection states were assessed after single administration, 1 and 2 months of treatment. In order to investigate the possible underlying mechanism, we also determined the alteration of testosterone, FSH and LH concentrations. KP at a dose of 90 mg day^-1 treated group exhibited a significant enhanced all parameters after 1 and 2 months of treatment. Moreover, the penile length at erection states and the response latency to sexual erotic stimuli appeared to be the parameters that showed significant changes during the delay period. Unfortunately, our study failed to show the significant changes on hormones concentration. Our study clearly demonstrates that KP is a potential resource for the development of nutraceutical compound against aged related male erectile dysfunction

At present, the effects of quercetin liposome on anxiolytic activity and cognitive function are unclearly known. In this study, male Wistar rats were administered quercetin liposome via intranasal route once daily continually for 4 weeks. The anxiolytic activity and cognitive enhancing effect were determined after single administration, 1, 2, 3 and 4 weeks of treatment using elevated plus maze test and Morris water maze test respectively. The results showed that quercetin liposome significantly increased both number of opened arm entry and time spent in the opened arm. In addition, the quercetin liposome also decreased escape latency and increased retention time markedly. Therefore, our results demonstrated the anxiolytic activity and cognitive enhancing effect of quercetin liposome and suggested that it might be used as a novel therapeutic strategy for anxiety disorder and cognitive deficit condition

Problem statement: At present, the development of protective strategy against Alzheimer’s Disease (AD) is increasing its importance due to the high prevalence of AD, a limitation of therapeutic efficacy and its high impacts on economic and social aspects. The development of the preventive and therapeutic strategy to protect against the path physiology induced by free radicals in AD from antioxidant has gained very much concentration. Quercetin, one of the flavonoids in fruits and vegetables, has a powerful antioxidant activity both in vitro and in vivo. However, poor absorption, rapid metabolism and limited ability to cross the blood-brain-barrier are obstacles to its use for treatment of AD. Liposome’s have been used as an effective delivery system to the brain. Advantages associated with the nasal administration over oral route include higher bioavailability due to no first pass hepatic metabolism and rapid absorption leading to shorter time to onset of effect. Based on all these points, the possible effects of quercetin liposomes via nasal route on improving cognitive behavior and neurodegeneration in animal model of Alzheimer’s disease were investigated. Approach: Male Wistar rats were pretreated with quercetin liposome’s, containing 0.5 mg of quercetin in 20 μL (dose = 20 μg), via intranasal route once daily continually for 2 weeks before and 1 week after AF64A administration. Learning and memory was evaluated using the Morris water maze test at 7 days after the AF64A administration and then the rats were sacrificed for determining the density of neurons and cholinergic neurons in hippocampus using histological and immunohistochemical techniques. Results: Nasal administration of quercetin liposome’s significantly prevented changes of spatial memory of AF64A treated rats. The cognitive enhancement of quercetin liposome’s was found to be related to its ability to inhibit the degeneration of neurons and cholinergic neurons in hippocampus. Conclusion: Nasal administration of quercetin liposome’s possessed cognitive enhancer and neuroprotectant in animal model of AD, suggesting a potential novel therapeutic strategy against AD of quercetin liposomes