Exploring the role of host specialisation and oxidative stress in interspecific lifespan variation in subtropical tephritid flies

The resistance of domestic canine skin-derived fibroblasts to oxidative and non-oxidative chemical injury: implications of breed and body size

Small-breed dogs live significantly longer lives than large-breed dogs, while having higher mass-specific metabolic rates and faster growth rates. Underlying this observed physiological difference across domestic dogs, there must also be differences at other levels of organization that could lead to elucidating what accounts for the disparity in aging rates and life span within this species. At the cellular level, a clear mechanism underlying whole animal traits has not been fully elucidated. Here, we cultured dermal fibroblasts from large and small breed dogs from both young and old age categories and examined the degree of resistance to multiple sources of cytotoxic stress. This included heat (42 °C), paraquat, cadmium, and hydrogen peroxide for increasing amounts of time (heat) or increasing concentrations (chemical stressors). We hypothesized that small breed dogs, with longer lifespans, would have greater cellular resistance to stress compared with large breed dogs. Final sample sizes include small puppies (N = 18), large puppy (N = 32), small old (N = 11), and large old (N = 23) dogs. Using a 2 (donor size) by 2 (donor age) between-subjects multivariate analysis of variance, we found that the values for the dose that killed 50% of the cells (LD50) were not significantly different based on donor size (p = 0.45) or donor age (p = 0.20). The interaction was also not significant (p = 0.47). Interestingly, we did find that the degree of resistance to cadmium toxicity was significantly correlated with the degree of resistance to both heat and hydrogen peroxide, but not paraquat (p < 0.01 for both). These data suggest that cellular stress resistance does not differ among domestic dogs as a function of size or age, pointing to other cellular pathways as the mechanistic basis for the observed differences in lifespan.

Comprehensive Nutritional and Functional Characterization of Novel Mycoprotein Derived from the Bioconversion of Durvillaea spp

This study aimed, for the first time, to determine the nutritional composition, beta-glucan and ergosterol contents, phenolic compound composition, and biological and functional activities of a novel mycoprotein produced through a bioconversion process of Durvillaea spp., a brown seaweed. An untargeted metabolomics approach was employed to screen metabolites and annotate molecules with nutraceutical properties. Two products, each representing a distinct consortia of co-cultured fungi, named Myco 1 and Myco 2, were analysed in this study. These consortia demonstrated superior properties compared to those of Durvillaea spp., showing significant increases in total protein (~238%), amino acids (~219%), and β-D-glucans (~112%). The protein contains all essential amino acids, a low fatty acid content, and exhibits high antioxidant activity (21.5-25.5 µmol TE/g). Additionally, Myco 2 exhibited the highest anti-alpha-glucosidase activity (IC50 = 16.5 mg/mL), and Myco 1 exhibited notable anti-lipase activity (IC50 = 10.5 mg/mL). Among the 69 top differentially abundant metabolites screened, 8 nutraceutical compounds were present in relatively high concentrations among the identified mycoproteins. The proteins and polysaccharides in the mycoprotein may play a crucial role in the formation and stabilization of emulsions, identifying it as a potent bioemulsifier. In conclusion, the bioconversion of Durvillaea spp. results in a mycoprotein with high-quality protein, significant nutritional and functional value, and prebiotic and nutraceutical potential due to the production of unique bioactive compounds.

Role of the mtDNA Mutations and Mitophagy in Inflammaging

Ageing is an unavoidable multi-factorial process, characterised by a gradual decrease in physiological functionality and increasing vulnerability of the organism to environmental factors and pathogens, ending, eventually, in death. One of the most elaborated ageing theories implies a direct connection between ROS-mediated mtDNA damage and mutations. In this review, we focus on the role of mitochondrial metabolism, mitochondria generated ROS, mitochondrial dynamics and mitophagy in normal ageing and pathological conditions, such as inflammation. Also, a chronic form of inflammation, which could change the long-term status of the immune system in an age-dependent way, is discussed. Finally, the role of inflammaging in the most common neurodegenerative diseases, such as Alzheimer’s and Parkinson’s, is also discussed.