## 5 Plant Compounds and Longevity
On the contrary, another study reported no beneficial effects of garlic and onion or their main bioactive compounds diallyl disulphide and dipropyl disulphide on _D. melanogaster_ lifespan, although, they exerted a protective role against H\({}_{2}\)O\({}_{2}\)-induced damage [188]. Some studies have analyzed the effects of some plants in mammalian models of accelerated senescence. In one approach, the longevity-promoting effects of the polyphenol oligomol were investigated in a mouse model of senescence acceleration (SAMP8). The effects were characterizedby increased oxidative stress and a neuronal deficit [189]. Oligonol treatment increased the mean life span, improved locomotive activity, and ameliorated the extent of inflammation around the eyes. However, in this study, the possible pathways involved in the extension of life expectancy were not investigated. Another study using the same SAMP8 mice model showed that resveratrol extends mean life expectancy and maximal life span, also reducing cognitive impairment [190]. The mechanism here was associated with an activation of the AMPK pathway and its downstream target, SIRT1, which protects against neurodegeneration. In addition, a reduction in the acetylated forms of p53, which are the main substrates of deacetylases (such as SIRT1), implicated in replicative senescence, was also observed. In another work, the beneficial effects of a phenolic extract from _Portulaca oleraca_ were investigated in a senescent mice model, induced by means of D-galactose/NaNO\({}_{2}\) treatment [191]. The phenolic extract reversed the reduced lifespan induced by D-galactose/NaNO\({}_{2}\) and improved spatial memory and learning ability. The underlying mechanism of survival and cognitive function seems have no relationship with acetylcholinesterasecholinesteraseterase (AChE), since the extract did not affect brain AChE activity. In addition, _P. oleracea_ ameliorated oxidative stress by increasing catalase activity and reducing MDA levels, reducing hippocampal morphological damage. [PERSON] et al. [192] studied the longevity-promoting effects of _Withania somifera_ extract in a SODI\({}^{G93\AA}\) mouse model of amyotrophic lateral sclerosis. _W. somifera_ treatment expanded mice longevity, enhanced motor performance, and augmented the quantity of motor neurons in the lumbar spinal cord. The extract exerted neuroprotective effects, delaying disease onset in part by promoting autophagy, as evidenced by increased p62 positive autophagic granules and LC3-II. Also, the protective effects of the extract could be related to an increase in the levels of Hsp-70, Hsp-60, and Hsp-27, derived from the activation of heat shock factor 1 (HSF-1). In obese mice, which are characterized by a reduced median lifespan, the longevity-promoting effects of a commercial polyphenol-rich extract were analyzed [193]. Although the treatment did not reverse obesity, it increased the life expectancy of the mice, improved endotoxin and reduced the degree of inflammation and accumulation in the adipose tissue of cholesterol and cholesterol oxides. Finally, the regulation of the length and function of telomeres is an important factor in maintaining health and longevity, and, thus, the epigenetic effects of some bioactive compounds can be an interesting approach to maintain their activity. In this sense, the water extract of turmeric (_Curcuna longa_) was reported to increase the expression of telomerase reverse transcriptase, which participates in the reduction of replicative senescence and extends the lifespan of many cell types, including RAW264.7 macrophages [194]. In another study, the effects of _Eutere operacea_ juice were studied. The juice was administered over four days to mice treated with lipopolysaccharideaccharide to induce a depressive-like behavior [195]. The treatment was capable of reducing despair-like and anhedonic behaviors and showed alterations in electromyographic analysis. In addition, _E.