Wipawee Thukham-mee

Moringa oleifera Mitigates Memory Impairment and Neurodegeneration in Animal Model of Age-Related Dementia

To date, the preventive strategy against dementia is still essential due to the rapid growth of its prevalence and the limited therapeutic efficacy. Based on the crucial role of oxidative stress in age-related dementia and the antioxidant and nootropic activities of Moringa oleifera, the enhancement of spatial memory and neuroprotection of M. oleifera leaves extract in animal model of age-related dementia was determined. The possible underlying mechanism was also investigated. Male Wistar rats, weighing 180–220 g, were orally given M. oleifera leaves extract at doses of 100, 200, and 400 mg/kg at a period of 7 days before and 7 days after the intracerebroventricular administration of AF64A bilaterally. Then, they were assessed memory, neuron density, MDA level, and the activities of SOD, CAT, GSH-Px, and AChE in hippocampus. The results showed that the extract improved spatial memory and neurodegeneration in CA1, CA2, CA3, and dentate gyrus of hippocampus together with the decreased MDA level and AChE activity but increased SOD and CAT activities. Therefore, our data suggest that M. oleifera leaves extract is the potential cognitive enhancer and neuroprotectant. The possible mechanism might occur partly via the decreased oxidative stress and the enhanced cholinergic function. However, further explorations concerning active ingredient(s) are still required.

Laser Acupuncture Improves Memory Impairment in an Animal Model of Alzheimer’s Disease

The burden of Alzheimers disease is continually rising globally, especially in the Asia-Pacific region. Unfortunately, the efficacy of the therapeutic strategy is still very limited. Because the effect of acupuncture at HT7 can improve learning and memory, the beneficial effect of laser acupuncture, a noninvasive form of acupuncture, at HT7 on memory improvement in patients with Alzheimers disease has been a focus of research. To elucidate this issue, we used AF64A, a cholinotoxin, to induce memory impairment in male Wistar rats, which weighed 180-220 g. Then, the animals were treated with laser acupuncture either at HT7 or at a sham acupoint once daily for 10 minutes for a period of 14 days. Spatial memory assessments were performed at 1, 7, and 14 days after AF64A administration and at the end of the experiment, and the changes in the malondialdehyde (MDA) level and in the superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and acetylcholinesterase (AChE) activities in the hippocampus were recorded. The results showed that laser acupuncture significantly suppressed AChE activity in the hippocampus. Although laser acupuncture enhanced SOD and CAT activities, no reduction in MDA level in this area was observed. Therefore, laser acupuncture at HT7 is a potential strategy to attenuate memory impairment in patients with Alzheimers disease. However, further research, especially on the toxicity of laser acupuncture following repetitive exposure, is essential.

Preventive Effect of Zea mays L. (Purple Waxy Corn) on Experimental Diabetic Cataract

Recently, substances possessing antioxidant can prevent cataractogenesis of diabetic cataract. Therefore, this study was carried out to determine the anticataract effect of Zea mays L. (purple waxy corn), a flavonoids rich plant, in experimental diabetic cataract. Enucleated rat lenses were incubated in artificial aqueous humor containing 55 mM glucose with various concentrations of Zea mays L. (purple waxy corn) ranging between 2, 10, and 50 mg/mL at room temperature for 72 h. At the end of the incubation period, the evaluation of lens opacification, MDA level, and the activities of SOD, CAT, GPx, and AR in lens were performed. The results showed that both medium and high doses of extract decreased lens opacity together with the decreased MDA level. In addition, medium dose of extract increased GPx activity while the high dose decreased AR activity. No other significant changes were observed. The purple waxy corn seeds extract is the potential candidate to protect against diabetic cataract. The mechanism of action may occur via the decreased oxidative stress and the suppression of AR. However, further research in vivo is still essential.

Mangifera indica Fruit Extract Improves Memory Impairment, Cholinergic Dysfunction, and Oxidative Stress Damage in Animal Model of Mild Cognitive Impairment

To date, the effective preventive paradigm against mild cognitive impairment (MCI) is required. Therefore, we aimed to determine whether Mangifera indica fruit extract, a substance possessing antioxidant and cognitive enhancing effects, could improve memory impairment, cholinergic dysfunction, and oxidative stress damage in animal model of mild cognitive impairment. Male Wistar rats, weighing 180–200 g, were orally given the extract at doses of 12.5, 50, and 200 mg·kg−1 BW for 2 weeks before and 1 week after the bilateral injection of AF64A (icv). At the end of study, spatial memory, cholinergic neurons density, MDA level, and the activities of SOD, CAT, and GSH-Px enzymes in hippocampus were determined. The results showed that all doses of extract could improve memory together with the decreased MDA level and the increased SOD and GSH-Px enzymes activities. The increased cholinergic neurons density in CA1 and CA3 of hippocampus was also observed in rats treated with the extract at doses of 50 and 200 mg·kg−1 BW. Therefore, our results suggested that M. indica, the potential protective agent against MCI, increased cholinergic function and the decreased oxidative stress which in turn enhanced memory. However, further researches are essential to elucidate the possible active ingredients and detail mechanism.

The Combined Extract of Purple Waxy Corn and Ginger Prevents Cataractogenesis and Retinopathy in Streptozotocin-Diabetic Rats

Based on the crucial roles of oxidative stress and aldose reductase on diabetic complications and the protective effect against diabetic eye complication of purple waxy corn and ginger (PWCG) together with the synergistic effect concept, we aimed to determine anticataract and antiretinopathy effects of the combined extract of purple waxy corn and ginger (PWCG). The streptozotocin diabetics with the blood glucose levels >250 mg·dL−1 were orally given the extract at doses of 50, 100, and 200 mg/kg·BW−1 for 10 weeks. Then, lens opacity and histopathology of retina were determined. The changes of MDA together with the activities of SOD, CAT, GPx, and AR in lens were also determined using biochemical assays. All doses of PWCG decreased lens opacity, MDA, and AR in the lens of diabetic rats. The elevation of CAT and GPx activities was also observed. The antiretinopathy property of the combined extract was also confirmed by the increased number of neurons in ganglion cell layer and thickness of total retina and retinal nuclear layer in diabetic rats. PWCG is the potential functional food to protect against diabetic cataract and retinopathy. However, further studies concerning toxicity and clinical trial are still essential.

Evaluation of Safety and Protective Effect of Combined Extract of Cissampelos pareira and Anethum graveolens (PM52) against Age-Related Cognitive Impairment

The present study aimed to determine acute toxicity, the protective effect, and underlying mechanism of PM52, a combined extract of Cissampelos pareira and Anethum graveolens, against age-related cognitive impairment in animal model of age-related cognitive impairment. PM52 was determined as acute toxicity according to OECD guideline. Male Wistar rats, weighing 180–220 g, were orally given PM52 at doses of 2, 10, and 50 mg/kg at a period of 14 days before and 7 days after the bilateral administration of AF64A via intracerebroventricular route. All animals were assessed according to spatial memory, neuron density, MDA level, the activities of SOD, CAT, GSH-Px, and AChEI effect in hippocampus. It was found that all doses of PM52 could attenuate memory impairment and neurodegeneration in hippocampus. The possible mechanisms might occur via the suppression of AChE and the decreased oxidative stress in hippocampus. Therefore, our data suggest that PM52 may serve as food supplement to protect against age-related cognitive impairment such as mild cognitive impairment (MCI) and early phase of Alzheimers disease. However, further researches are still essential.

Anethum graveolens Linn. (dill) extract enhances the mounting frequency and level of testicular tyrosine protein phosphorylation in rats

ObjectiveTo investigate the effect of Anethum graveolens (AG) extracts on the mounting frequency, histology of testis and epididymis, and sperm physiology.MethodsMale rats induced by cold immobilization before treating with vehicle or AG extracts [50, 150, and 450 mg/kg body weight (BW)] via gastric tube for consecutive 1, 7, and 14 d were examined for mounting frequency, testicular phosphorylation level by immunoblotting, sperm concentration, sperm acrosome reaction, and histological structures of testis and epididymis, respectively.ResultsAG (50 mg/kg BW) significantly increased the mounting frequency on Days 1 and 7 compared to the control group. Additionally, rat testis treated with 50 mg/kg BW AG showed high levels of phosphorylated proteins as compared with the control group. In histological analyses, AG extract did not affect the sperm concentration, acrosome reaction, and histological structures of testis and epididymis.ConclusionsAG extract enhances the aphrodisiac activity and is not harmful to sperm and male reproductive organs.

Antiosteoporotic Effect of Combined Extract of Morus alba and Polygonum odoratum

Due to the limitation of osteoporosis therapy, the alternative therapies from natural sources have been considered. In this study, we aimed to determine the antiosteoporotic effect of the combined extract of Morus alba and Polygonum odoratum leaves. Ovariectomized rats, weighing 200–220 g, were orally given the combined extract at doses of 5, 150, and 300 mg·kg−1 BW for 3 months. At the end of study, blood was collected to determine serum osteocalcin, calcium, and alkaline phosphatase level. In addition, tibia bone was isolated to determine bone oxidative stress markers, cortical bone thickness, and density of osteoblast. The combined extract decreased oxidative stress and osteoclast density but increased osteoblast density and cortical thickness. The elevation of serum calcium, alkaline phosphatase, and osteocalcin was also observed. These results suggested the antiosteoporotic effect of the combined extract via the increased growth formation together with the suppression of bone resorption. However, further studies concerning chronic toxicity and the underlying mechanism are required.

Protocatechuic Acid Restores Vascular Responses in Rats With Chronic Diabetes Induced by Streptozotocin

Oxidative stress has been shown to play an important role in development of vascular dysfunction in diabetes. Protocatechuic acid (PCA) has been reported to exert antioxidant and anti‐hyperglycemic activities. Diabetes was induced in male Sprague–Dawley rats by a single intraperitoneal injection of 50 mg/kg streptozotocin (STZ). The rats were maintained in a state of hyperglycemia for 12 weeks. Then, PCA (50 or 100 mg/kg/day) was administered orally or insulin (4 U/kg/day) was subcutaneous injected to the rats for 6 weeks. Blood pressure, vascular responses to vasoactive agents, vascular superoxide production, blood glucose, insulin, malondialdehyde, nitric oxide and antioxidant enzymes were examined. The diabetic rats showed weight loss, insulin deficiency, hyperglycemia, increased oxidative stress, decreased plasma nitric oxide, elevated blood pressure, increased vascular response to phenylephrine and decreased vascular responses to acetylcholine and sodium nitroprusside. PCA significantly decreased blood glucose and oxidative stress, and increased plasma nitric oxide in diabetic rats. Interestingly, PCA treatment restored blood pressure and vascular reactivity, and antioxidant enzyme activity diabetic rats. This study provides the first evidence of the efficacy of PCA in restoring the vascular reactivity of diabetic rats. The mechanism of action may be associated with an alleviation of oxidative stress. Copyright

The Combined Extract of Zingiber officinale and Zea mays (Purple Color) Improves Neuropathy, Oxidative Stress, and Axon Density in Streptozotocin Induced Diabetic Rats.

Based on the protective effect of the combined extract of purple waxy corn and ginger (PWCG) on oxidative stress related disorders in diabetic condition, we aimed to determine the effect of PWCG on the functional, biochemical, and structural change of the lesion nerve in streptozotocin- (STZ-) diabetic rats. PWCG at doses of 100, 200, and 300 mg·kg−1 BW were orally given to STZ-diabetic rats which were subjected to chronic constriction (CCI) at right sciatic nerve for 21 days. The blood sugar was assessed before and at the end of study whereas the sciatic function index (SFI), paw withdrawal threshold intensity (PWTI), and paw withdrawal latency (PWL) were assessed every 3 days until the end of study. At the end of study, the determination of nerve conduction velocity (NCV), axon density, oxidative stress status, and aldose reductase (AR) activity of the lesion nerve were performed. It was found that PWCG improved SFI, PWTI, PWL, and NCV together with the improved oxidative stress status and the axon density in the lesion nerve. No changes of AR activity or blood sugar level were observed. Therefore, PWCG might improve the functional and structural changes in STZ-diabetic rats plus CCI via the improved oxidative stress status.