Nicandra physalodes Extract Exerts Antiaging Effects in Multiple Models and Extends the Lifespan of Caenorhabditis elegans via DAF-16 and HSF-1.

The development of safe and effective therapeutic interventions is an important issue for delaying aging and reducing the risk of aging-related diseases. Chinese herbal medicines for the treatment of aging and other complex diseases are desired due to their multiple components and targets. Through screening for effects on lifespan of 836 Chinese herbal medicine extracts, Nicandra physalodes extract (HL0285) was found to exhibit lifespan extension activity in Caenorhabditis elegans (C. elegans). In further experiments, HL0285 improved healthspan, enhanced stress resistance, and delayed the progression of neurodegenerative diseases in C. elegans. Additionally, it ameliorated senescence in human lung fibroblasts (MRC-5 cells) and reversed liver function damage and reduced senescence marker levels in doxorubicin- (Dox-) induced aging mice. In addition, the longevity effect of HL0285 in C. elegans was dependent on the DAF-16 and HSF-1 signaling pathways, as demonstrated by the results of the mutant lifespan, gene level, and GFP level assays. In summary, we discovered that HL0285 had an antiaging effect in C. elegans, MRC-5 cells, and Dox-induced aging mice and deserves to be explored in the future studies on antiaging agents.

Crotamiton derivative JM03 extends lifespan and improves oxidative and hypertonic stress resistance in Caenorhabditis elegans via inhibiting OSM-9.

While screening our in-house 1072 marketed drugs for their ability to extend the lifespan using Caenorhabditis elegans (C. elegans) as an animal model, crotamiton (N-ethyl-o-crotonotoluidide) showed anti-aging activity and was selected for further structural optimization. After replacing the ortho-methyl of crotamiton with ortho-fluoro, crotamiton derivative JM03 was obtained and showed better activity in terms of lifespan-extension and stress resistance than crotamiton. It was further explored that JM03 extended the lifespan of C. elegans through osmotic avoidance abnormal-9 (OSM-9). Besides, JM03 improves the ability of nematode to resist oxidative stress and hypertonic stress through OSM-9, but not osm-9/capsaicin receptor related-2 (OCR-2). Then the inhibition of OSM-9 by JM03 reduces the aggregation of Q35 in C. elegans via upregulating the genes associated with proteostasis. SKN-1 signaling was also found to be activated after JM03 treatment, which might contribute to proteostasis, stress resistance and lifespan extension. In summary, this study explored a new small molecule derived from crotamiton, which has efficient anti-oxidative, anti-hypertonic, and anti-aging effects, and could further lead to promising application prospects.

Characterization of cellular senescence in doxorubicin-induced aging mice.

With a rise in the need to develop anti-aging drugs, a growing number of in vivo studies evaluating the efficacy of potential drug candidates have used doxorubicin-induced aging mice. However, changes in the biomarkers of senescent cells have not been reported in detail in these animals. To lay a foundation for the use of doxorubicin-induced aging mice, we examined the biomarkers of hepatic and renal senescent cells in these mice. We found that the 5 mg/kg doxorubicin dose is optimal to induce cellular senescence in mice. Subsequently, using this dose, we found that doxorubicin-induced an increase in senescence-associated ß-galactosidase (SA-ß-gal) positive cells in the kidney and lipofuscin accumulation in the liver. Some markers of senescent cells (p21WAF1/CIP1, p16INK4A, and γH2AX) were also significantly upregulated by doxorubicin and then counteracted by metformin treatment. These preliminary findings support the application of doxorubicin-induced aging mice as an animal model to evaluate the efficacy of anti-aging drug candidates.

Anti-aging effects of chlorpropamide depend on mitochondrial complex-II and the production of mitochondrial reactive oxygen species.

Sulfonylureas are widely used oral anti-diabetic drugs. However, its long-term usage effects on patients' lifespan remain controversial, with no reports of influence on animal longevity. Hence, the anti-aging effects of chlorpropamide along with glimepiride, glibenclamide, and tolbutamide were studied with special emphasis on the interaction of chlorpropamide with mitochondrial ATP-sensitive K+ (mitoK-ATP) channels and mitochondrial complex II. Chlorpropamide delayed aging in Caenorhabditis elegans, human lung fibroblast MRC-5 cells and reduced doxorubicin-induced senescence in both MRC-5 cells and mice. In addition, the mitochondrial membrane potential and ATP levels were significantly increased in chlorpropamide-treated worms, which is consistent with the function of its reported targets, mitoK-ATP channels. Increased levels of mitochondrial reactive oxygen species (mtROS) were observed in chlorpropamide-treated worms. Moreover, the lifespan extension by chlorpropamide required complex II and increased mtROS levels, indicating that chlorpropamide acts on complex II directly or indirectly via mitoK-ATP to increase the production of mtROS as a pro-longevity signal. This study provides mechanistic insight into the anti-aging effects of sulfonylureas in C. elegans.

Antiaging Effects of Vicatia thibetica de Boiss Root Extract on Caenorhabditis elegans and Doxorubicin-Induced Premature Aging in Adult Mice.

The roots of Vicatia thibetica de Boiss are a kind of Chinese herb with homology of medicine and food. This is the first report showing the property of the extract of Vicatia thibetica de Boiss roots (HLB01) to extend the lifespan as well as promote the healthy parameters in Caenorhabditis elegans (C. elegans). For doxorubicin- (Doxo-) induced premature aging in adult mice, HLB01 counteracted the senescence-associated biomarkers, including P21 and γH2AX. Interestingly, HLB01 promoted the expression of collagen in C. elegans and mammalian cell systemically, which might be one of the essential factors to exert the antiaging effects. In addition, HLB01 was also found as a scavenger of free radicals, thereby performing the antioxidant ability. Lifespan extension by HLB01 was also dependent on DAF-16 and HSF-1 via oxidative stress resistance and heat stress resistance. Taken together, overall data suggested that HLB01 could extend the lifespan and healthspan of C. elegans and resist Doxo-induced senescence in mice via promoting the expression of collagen, antioxidant potential, and stress resistance.

Verapamil extends lifespan in Caenorhabditis elegans by inhibiting calcineurin activity and promoting autophagy.

Previous evidence has revealed that increase in intracellular levels of calcium promotes cellular senescence. However, whether calcium channel blockers (CCBs) can slow aging and extend lifespan is still unknown. In this study, we showed that verapamil, an L-type calcium channel blocker, extended the Caenorhabditis elegans (C. elegans) lifespan and delayed senescence in human lung fibroblasts. Verapamil treatment also improved healthspan in C. elegans as reflected by several age-related physiological parameters, including locomotion, thrashing, age-associated vulval integrity, and osmotic stress resistance. We also found that verapamil acted on the α1 subunit of an L-type calcium channel in C. elegans. Moreover, verapamil extended worm lifespan by inhibiting calcineurin activity. Furthermore, verapamil significantly promoted autophagy as reflected by the expression levels of LGG-1/LC3 and the mRNA levels of autophagy-related genes. In addition, verapamil could not further induce autophagy when tax-6, calcineurin gene, was knocked down, indicating that verapamil-induced lifespan extension is mediated via promoting autophagy processes downstream of calcineurin. In summary, our study provided mechanistic insights into the anti-aging effect of verapamil in C. elegans.

Lactose induced redox-dependent senescence and activated Nrf2 pathway.

Lactose is a disaccharide found in milk and thus a part of our daily food intake. Upon ingestion, it is hydrolyzed to glucose and galactose by the enzyme lactase and absorbed in the small intestine. People who suffer from lactose intolerance are unable to completely digest it due to deficiency of lactase, leading to intestinal problems such as diarrhoea, and bloating. Various studies have focused on treating these symptoms. However, the effects of lactose that diffuses passively into cells, on cellular senescence have largely remained unknown. Thus, the present study investigated the effects and mechanisms of lactose on senescence both in vitro and in vivo. The study was conducted in MRC-5 cells. The cellular senescence was estimated by determining the expression of SA-ß-gal and p16ink4a. The cell viability of MRC-5 cells was determined by the CCK-8 Assay. Activity of intracellular reactive oxygen species was estimated by measuring the levels of superoxide dismutase (SOD), glutathione (GHS), and reactive oxygen species (ROS). The mechanism of lactose on cellular senescence was explored by western blotting. We also studied the effect of lactose on the lifespan of Caenorhabditis elegans. Increased activities of SA-ß-gal and p16ink4a revealed the ability of lactose to induce senescence in MRC-5 cells. The elevated intracellular ROS level and decreased GSH and SOD levels in these cells were indicative of cellular oxidative stress induced by lactose. Furthermore, western blotting analysis of Nrf2 and mRNA expression of its downstream genes suggested the Nrf2/ARE pathway was involved in the oxidative stress induced by lactose. These results were further validated by the shortened lifespan of C. elegans after lactose supplement. Moreover, the lactose-induced senescence could be alleviated by an antioxidant, N-Acetyl-L-cysteine (NAC), both in vitro and in vivo. The present study observed a positive correlation between lactose and cellular oxidative stress, suggesting the latter to be an underlying mechanism of lactose-induced senescence.

A comparative assessment of cytotoxicity of commonly used agricultural insecticides to human and insect cells.

The cytotoxic potential of 13 commonly used agricultural insecticides was examined using cell-based systems with three human HepG2, Hek293, HeLa cells and three insect Tn5B1-4, Sf-21, and Drosophila S2 cells. Data showed that (1) an enhancement of some insecticides (e.g. pyrethroids) on cells proliferation; (2) an inhibition of some insecticides on cells viability; (3) various levels of susceptibility of different cells to the same insecticide; and (4) the cell type dependent sensitivity to different insecticides. The degree of cytotoxicity of insecticides on human cells was significantly lower than that on insect cells (P<0.05). Methomyl, even 20µg/ml, showed little cytotoxicity at 24h exposure whereas emamectin benzoate possessed the strongest cytotoxic potential in a dose-dependent fashion. The results revealed comparable cytotoxic property of agricultural insecticides against intact cells.