Starvation differentially affects gene expression, immunity and pathogen susceptibility across symbiotic states in a model cnidarian.

Mutualistic symbioses between cnidarians and photosynthetic algae are modulated by complex interactions between host immunity and environmental conditions. Here, we investigate how symbiosis interacts with food limitation to influence gene expression and stress response programming in the sea anemone Exaiptasia pallida (Aiptasia). Transcriptomic responses to starvation were similar between symbiotic and aposymbiotic Aiptasia; however, aposymbiotic anemone responses were stronger. Starved Aiptasia of both symbiotic states exhibited increased protein levels of immune-related transcription factor NF-κB, its associated gene pathways, and putative target genes. However, this starvation-induced increase in NF-κB correlated with increased immunity only in symbiotic anemones. Furthermore, starvation had opposite effects on Aiptasia susceptibility to pathogen and oxidative stress challenges, suggesting distinct energetic priorities under food scarce conditions. Finally, when we compared starvation responses in Aiptasia to those of a facultative coral and non-symbiotic anemone, 'defence' responses were similarly regulated in Aiptasia and the facultative coral, but not in the non-symbiotic anemone. This pattern suggests that capacity for symbiosis influences immune responses in cnidarians. In summary, expression of certain immune pathways-including NF-κB-does not necessarily predict susceptibility to pathogens, highlighting the complexities of cnidarian immunity and the influence of symbiosis under varying energetic demands.

Starvation decreases immunity and immune regulatory factor NF-κB in the starlet sea anemone Nematostella vectensis.

Lack of proper nutrition has important consequences for the physiology of all organisms, and nutritional status can affect immunity, based on many studies in terrestrial animals. Here we show a positive correlation between nutrition and immunity in the sea anemone Nematostella vectensis. Gene expression profiling of adult anemones shows downregulation of genes involved in nutrient metabolism, cellular respiration, and immunity in starved animals. Starved adult anemones also have reduced protein levels and activity of immunity transcription factor NF-κB. Starved juvenile anemones have increased sensitivity to bacterial infection and also have lower NF-κB protein levels, as compared to fed controls. Weighted Gene Correlation Network Analysis (WGCNA) is used to identify significantly correlated gene networks that were downregulated with starvation. These experiments demonstrate a correlation between nutrition and immunity in an early diverged marine metazoan, and the results have implications for the survival of marine organisms as they encounter changing environments.

Aging and the Indian Face: An Analytical Study of Aging in the Asian Indian Face.

Asian Indians make up almost one-sixth of the world's population. Although some aspects of facial beauty are universal, anthropometric morphology and age-related changes differ in all ethnic groups. Currently, there are hardly any published studies highlighting the process of aging in Asian Indians. We wanted to understand the aging patterns in different ethnic subgroups within Asian Indians and also compare the aging patterns with Caucasians. METHOD: 300 participants, above 30 years of age, were selected from different Indian ethnic groups (North, South, East, West). Recent good-quality photographs as well as those from the preceding decades (20 years and beyond) were studied. A validated grading score of 1-5 was used for assessing various aging parameters. RESULTS: Significant differences exist in the process of aging between Asian Indians and Caucasians. Maximum signs of aging were reported in the age group of >70 years. Earlier signs of aging (in 30-40 years) were more visible in North and East Indian ethnic groups followed by West and South Indians in decreasing order. Also, South Indians showed the least signs of aging (early as well as overall) compared to the other 3 ethnic groups in any given age range. CONCLUSIONS: This study attempts to understand in greater detail the aging process of the Asian Indian population. This study could open up specific treatment protocols to treat this population in the fields of facial esthetics and facial cosmetic surgery.