Effects of Pesticides on Longevity and Bioenergetics in Invertebrates—The Impact of Polyphenolic Metabolites

Environmentally hazardous substances such as pesticides are gaining increasing interest in agricultural and nutritional research. This study aims to investigate the impact of these compounds on the healthspan and mitochondrial functions in an invertebrate in vivo model and in vitro in SH-SY5Y neuroblastoma cells, and to investigate the potential of polyphenolic metabolites to compensate for potential impacts. Wild-type nematodes (Caenorhabditis elegans, N2) were treated with pesticides such as pyraclostrobin (Pyr), glyphosate (Gly), or fluopyram (Fluo). The lifespans of the nematodes under heat stress conditions (37 °C) were determined, and the chemotaxis was assayed. Energetic metabolites, including adenosine triphosphate (ATP), lactate, and pyruvate, were analyzed in lysates of nematodes and cells. Genetic expression patterns of several genes associated with lifespan determination and mitochondrial parameters were assessed via qRT-PCR. After incubation with environmentally hazardous substances, nematodes were incubated with a pre-fermented polyphenol mixture (Rechtsregulat®Bio, RR) or protocatechuic acid (PCA) to determine heat stress resistance. Treatment with Pyr, Glyph and Fluo leads to dose-dependently decreased heat stress resistance, which was significantly improved by RR and PCA. The chemotaxes of the nematodes were not affected by pesticides. ATP levels were not significantly altered by the pesticides, except for Pyr, which increased ATP levels after 48 h leads. The gene expression of healthspan and mitochondria-associated genes were diversely affected by the pesticides, while Pyr led to an overall decrease of mRNA levels. Over time, the treatment of nematodes leads to a recovery of the nematodes on the mitochondrial level but not on stress resistance on gene expression. Fermented extracts of fruits and vegetables and phenolic metabolites such as PCA seem to have the potential to recover the vitality of C. elegans after damage caused by pesticides.

The DegU Orphan Response Regulator Contributes to Heat Stress Resistance in Listeria monocytogenes

Listeria monocytogenes is more heat-resistant than most other non-spore-forming foodborne pathogens, posing a severe threat to food safety and human health, particularly during chilled food processing. The DegU orphan response regulator is known to control heat resistance in L. monocytogenes; however, the underlying regulatory mechanism is poorly understood. Here, we show that DegU contributes to L. monocytogenes exponential growth under mild heat-shock stress. We further demonstrate that DegU directly senses heat stress through autoregulation and upregulates the hrcA-grpE-dnaK-dnaJ operon, leading to increased production of heat-shock proteins. We also show that DegU can directly regulate the expression of the hrcA-grpE-dnaK-dnaJ operon. In conclusion, our results shed light on the regulatory mechanisms underlying how DegU directly activates the hrcA-grpE-dnaK-dnaJ operon, thereby regulating heat resistance in L. monocytogenes.

An Evaluation of Different Quail Varieties for the Heat Stress Resistance

The aim of this study was to evaluate some biochemical variables under heat-stressed Japanese quail that have different plumage colors for detecting that variety of quail better adapted to heat stress. A total of 100 birds were used in this study. The 25 birds that belong to each four plumage color group were placed in 5-tiered including 3 compartments in each tier plastic cages with subdivided 5 repetitions according to their initial body weights. The statistical significance occurred in LDH (P<0.01). The highest LDH level was found in the Recessive white variety (25.43 mmol/L), followed by Wild type (23.78 mmol/L), Golden (12.87 mmol/L), and Tuxedo (12.71 mmol/L), respectively. The Recessive white group was different from the Golden and Tuxedo groups. According to the results of the current study, there was no significant difference was observed between the four different color varieties of Japanese quail regarding heat stress. However, when LDH is taken into account, it can be thought that the white color may be more sensitive to stress. In order to clarify exactly this situation, more studies that are detailed such as yield performance can be conducted on different quail species.

Intergenerational hormesis is regulated by heritable 18S rRNA methylation

SummaryHeritable non-genetic information can regulate a variety of complex phenotypes. However, what specific non-genetic cues are transmitted from parents to their descendants are poorly understood. Here, we perform metabolic methyl-labelling experiments to track the heritable transmission of methylation from ancestors to their descendants in the nematode Caenorhabditis elegans. We find that methylation is transmitted to descendants in proteins, RNA, DNA and lipids. We further find that in response to parental starvation, fed naïve progeny display reduced fertility, increased heat stress resistance, and extended longevity. This intergenerational hormesis is accompanied by a heritable increase in N6’-dimethyl adenosine (m6,2A) on the 18S ribosomal RNA at adenosines 1735 and 1736. We identified the conserved DIMT-1 as the m6,2A methyltransferase in C. elegans and find that dimt-1 is required for the intergenerational hormesis phenotypes. This study provides the first labeling and tracking of heritable non-genetic material across generations and demonstrates the importance of rRNA methylation for regulating the heritable response to starvation.

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.

Dietary Laminaria japonica Polysaccharide Regulates Systemic Defence Property of Weaned Piglets Improving Growth Performance under High Temperature Condition

Background: This study was conducted to evaluate the effect of dietary LJP supplementation on growth performance, heat stress resistance and immune status of weaned piglets raised in a high-temperature environment (34 ± 3°C).Methods: A total of 72 Barkshire × Licha Black crossbred piglets were weaned at 30 days of age (BW, 5.88 ± 0.16 kg) and fed either without or with 100, 200 or 400 mg/kg LJP in a completely randomized design, with 3 pens per diet (6 pigs per pen). On day 21, a total of 12 piglets were selected to collect blood samples.Result: The results showed that 200 and 400 mg/kg LJP supplementation decreased the feed conversion ratio (FCR) of piglets compared to the control group (P = 0.037) and dietary LJP linearly increased average daily gain and decreased FCR of piglets (P = 0.037 and 0.011, respectively). In addition, adding 100, 200 and 400 mg/kg LJP reduced the serum HSP70 content compared to the control group (P = 0.019) and dietary LJP linearly and quadratically decreased the serum HSP70 content of piglets (P = 0.030 and 0.011, respectively). Moreover, supplementation of 200 mg/kg and 400 mg/kg LJP increased the serum (NO) and nitric oxide acid phosphatase (ACP) content compared to the control group (P = 0.019; P = 0.003) and dietary LJP linearly increased the serum lysozyme, NO and ACP contents (P = 0.039; P = 0.005; P = 0.001). In conclusion, dietary LJP has potential to regulate systemic defence property of weaned piglets raised in a high temperature condition, accompanied by increased growth performance.

Genes implicated in Caenorhabditis elegans and human health regulate stress resistance and physical abilities in aged Caenorhabditis elegans

Recently, nine Caenorhabditis elegans genes, grouped into two pathways/clusters, were found to be implicated in healthspan in C. elegans and their homologues in humans, based on literature curation, WormBase data mining and bioinformatics analyses. Here, we further validated these genes experimentally in C. elegans . We downregulated the nine genes via RNA interference (RNAi), and their effects on physical function (locomotion in a swim assay) and on physiological function (survival after heat stress) were analysed in aged nematodes. Swim performance was negatively affected by the downregulation of acox-1.1 , pept-1 , pak-2 , gsk-3 and C25G6.3 in worms with advanced age (twelfth day of adulthood) and heat stress resistance was decreased by RNAi targeting of acox-1.1 , daf-22 , cat-4 , pig-1 , pak-2 , gsk-3 and C25G6.3 in moderately (seventh day of adulthood) or advanced aged nematodes. Only one gene, sad-1 , could not be linked to a health-related function in C. elegans with the bioassays we selected. Thus, most of the healthspan genes could be re-confirmed by health measurements in old worms.