Cardiovascular protective effect of nano selenium in hypothyroid rats: protection against oxidative stress and cardiac fibrosis.

BACKGROUND: Nano selenium (Nano Sel) has many therapeutic properties including antioxidant, anticancer, and anti-inflammatory actions. OBJECTIVE: Impacts of Nano Sel administration against cardiac fibrosis and heart and aorta tissue oxidative damage observed in hypothyroid rats were explored. METHODS: The animals were randomly grouped and treated as: 1) Control; 2) Propylthiouracil (PTU) in which PTU was added to the drinking water (0.05%) to induce hypothyroidism; 3-5) PTU-Nano Sel 50, PTU-Nano Sel 100, and PTU-Nano Sel 150 groups, which received daily PTU plus 50,100 or 150 µg/kg of Nano Sel for 6 weeks intraperitoneally. The heart and aorta tissues were removed under deep anesthesia and then biochemical parameters including malondialdehyde (MDA), total thiol groups, catalase (CAT), and superoxide dismutase (SOD), as well as cardiac fibrosis were assessed. RESULTS: Hypothyroidism induced by PTU was remarkably associated with myocardial hypertrophy and perivascular fibrosis in Masson's trichrome staining. Moreover, hypothyroidism increased MDA level, while it subtracted total thiol group content and activity of SOD and CAT. Treatment with Nano Sel recovered hypothyroidism-induced cardiac fibrosis in the histological assessment. Nano Sel also promoted CAT and SOD activity and thiol content, whereas alleviated MDA levels in the heart and aorta tissues. CONCLUSION: Results propose that administration of Nano Sel exerts a protective role in the cardio vascular system via preventing cardiac fibrosis and inhibiting oxidative stress.

Grape seed extract effects on hippocampal neurogenesis, synaptogenesis and dark neurons production in old mice. Can this extract improve learning and memory in aged animals?

BACKGROUND: During the elderly, hippocampal neurogenesis and synaptogenesis reduce and dark neurons (DNs) increase, leading to cognitive impairment. It is believed that natural products can protect the neural cells and system by protecting from damages or promoting regeneration. Therefore, the effects of grape seed extract (GSE) on the hippocampus of aged mice were investigated in this study. METHODS: twelve old mice were divided into two groups of control and GSE. Animals in the GSE group received 300 mg/kg of GSE for eight weeks via gavage. At the end of treatment, cognition performance was evaluated by Morris water maze (MWM) and passive avoidance tests. Hippocampal neurogenesis, synaptogenesis and DNs production were evaluated with immunohistochemistry and histological evaluations on 5-micron coronal tissue sections. RESULTS: The hippocampal mean number of double cortin positive cells (DCX+) per unit area, as well as synaptophysin expression in the GSE group, were significantly higher than the control group (p < 0.01). The frequency of DNs in the GSE group was lower than the control group (p < 0.05). Behavioral tests showed that GSE improves memory and learning performance. CONCLUSION: Consuming GSE in the elderly can potentially alleviate the age-related reduction of hippocampal neurogenesis and synaptogenesis. It is also able to decrease hippocampal DNs production and increase memory and learning.