Alzheimer’s disease (AD) is related to increasing age. It is mainly characterized by progressive neurodegenerative disease, which damages memory and cognitive function. Natural products offer many options to reduce the progress and symptoms of many kinds of diseases, including AD. Meanwhile, natural compound structures, including lignans, flavonoids, tannins, polyphenols, triterpenes, sterols, and alkaloids, have anti-inflammatory, antioxidant, anti-amyloidogenic, and anticholinesterase activities. In this review, we summarize the pathogenesis and targets for treatment of AD. We also present several medicinal plants and isolated compounds that are used for preventing and reducing symptoms of AD.

Curcuma longa, which contains curcumin as a major constituent, has been shown many pharmacological effects, but it is limited using in clinical due to low bioavailability. In this study, we developed a phytosome curcumin formulation and evaluated the hepatoprotective effect of phytosome curcumin on paracetamol induced liver damage in mice. Phytosome curcumin (equivalent to curcumin 100 and 200 mg/kg body weight) and curcumin (200 mg/kg body weight) were given by gastrically and toxicity was induced by paracetamol (500 mg/kg) during 7 days. On the final day animals were sacrificed and liver function markers (ALT, AST), hepatic antioxidants (SOD, CAT and GPx) and lipid peroxidation in liver homogenate were estimated. Our data showed that phytosome has stronger hepatoprotective effect compared to curcumin-free. Administration of phytosome curcumin effectively suppressed paracetamol-induced liver injury evidenced by a reduction of lipid peroxidation level, and elevated enzymatic antioxidant activities of superoxide dismutase, catalase, glutathione peroxidase in mice liver tissue. Our study suggests that phytosome curcumin has strong antioxidant activity and potential hepatoprotective effects.

Resveratrol (RSV) is a bioactive natural molecule that induces antioxidant activity and increases protection against oxidative damage. RSV could be used to mitigate damages associated to metabolic diseases and aging. Particularly, RSV regulates different aspects of mitochondrial metabolism. However, no information is available about the effects of RSV on Coenzyme Q (CoQ), a central component in the mitochondrial electron transport chain. Here, we report for the first time that RSV modulates COQ genes and parameters associated to metabolic syndrome in mice. Mice fed with high fat diet (HFD) presented a higher weight gain, triglycerides (TGs) and cholesterol levels while RSV reverted TGs to control level but not weight or cholesterol. HFD induced a decrease of COQs gene mRNA level, whereas RSV reversed this decrease in most of the COQs genes. However, RSV did not show effect on CoQ₉, CoQ₁₀ and total CoQ levels, neither in CoQ-dependent antioxidant enzymes. HFD influenced mitochondrial dynamics and mitophagy markers. RSV modulated the levels of PINK1 and PARKIN and their ratio, indicating modulation of mitophagy. In summary, we report that RSV influences some of the metabolic adaptations of HFD affecting mitochondrial physiology while also regulates COQs gene expression levels in a process that can be associated with mitochondrial dynamics and turnover.

Background: Sanchezia speciosa has been used in traditional medicine for gastritis treatment in Vietnam. Some phytochemical study showed that S. speciosa contains high amounts of flavonoids and cardiac glycoside compounds. In the present study, we isolated four compounds from the ethanol extract of the S. speciosa leaf, and we evaluated the in vitro antioxidant and anti-inflammatory effect of the isolated compound from the ethanol extract of the S. speciosa leaf. Methods: The leaf of S. speciosa Leonard was extracted with ethanol 96%. Compounds were isolated using column chromatography and identified by spectroscopic method, including IR, MS, and NMR and by comparing their physicochemical and spectral data with those published in literatures. These isolated compounds were investigated for their antioxidant activity using DPPH and inflammation inhibitory activity by inhibition of albumin denaturation assay. Results: We have isolated four compounds quercetin 3- O - α - l -rhamnopyranosid ( quercitrin ) (1), quercetin 3- O-β- d -galactopyranosid (hyperosid) (2), sitosterol-3-O-β-D-glucopyranosid (daucosterol) (3), and 3-methyl-1H-benz[f]indole-4,9-dione (4) from the ethanolic extract of the S. speciosa leaf. The antioxidant activities were in the following order: compound 2 >compound 1>compound 4 >compound 3 . The IC ₅₀ values of scavenging DPPH radicals for compound 2 was 20.83±1.29 μg/mL. For anti-inflammatory activities, the order was compound 4 >compound 3 >compound 2 >compound 1 . Compound 4 showed the strongest inhibition, with IC50 values of 193.70±5.24 µg/mL. Conclusions: These compounds 1 , 2 , and 4 were isolated for the first time from the leaves of S. speciosa. These compounds showed strong antioxidant and anti-inflammatory activity.