Animals use diverse signal types (e.g. visual, auditory) to honestly advertise their genotypic and/or phenotypic quality to prospective mates or rivals. Behavioral displays and other dynamically updateable signals (e.g. songs, vibrations) can reliably reveal an individual’s quality in real-time, but it is unclear whether more fixed traits like feather coloration, which is often developed months before breeding, still reveal an individual’s quality at the time of signal use. To address this gap, we investigated if various indices of health and condition – including body condition (residual body mass), poxvirus infection, degree of habitat urbanization, and circulating levels of ketones, glucose, vitamins, and carotenoids – were related to the expression of male plumage coloration at the start of the spring breeding season in wild male house finches (Haemorhous mexicanus), a species in which many studies have demonstrated a link between plumage redness and the health and condition of individuals at the time the feathers are grown in late summer and autumn. We found that, at the time of pair formation, plumage hue was correlated with body condition, such that redder males were in better condition (i.e. higher residual mass). Also, as in previous studies, we found that rural males had redder plumage; however, urban males had more saturated plumage. In sum, these results reveal that feather coloration developed long before breeding still can be indicative to choosy mates of a male’s current condition and suggest that females who prefer to mate with redder males may also gain proximate material benefits (e.g. better incubation provisioning) by mating with these individuals in good current condition.
Bioindicators of wildlife health are useful tools for studying the viability of various organisms and populations, and can include a range of phenotypic variables, such as behavior, body size, and physiological parameters, such as circulating hormones and nutrients. Few studies have investigated the utility of total plasma protein as a predictor of environmental or nutritional variation among birds, as well as variation across different seasons and life-history stages. Here I examined relationships between plasma protein and season, urbanization, sex, body condition, molt status, and disease state in house finches (Haemorhous mexicanus). I sampled blood from house finches across three seasons (winter, summer and fall 2021) and measured plasma protein levels using a Bradford assay. I also collected data including condition, sex, and poxvirus infection state at capture, as well as fecal samples to assess gut parasitism (coccidiosis). During the fall season I also estimated molt status, as number of actively growing feathers. I found circulating plasma protein concentration to be lower in the fall during molt than during winter or summer. I also found a significant relationship between circulating protein levels and capture site, as well as novel links to molt state and pox presence, with urban birds, those infected with pox, and those in more intense molt having higher protein levels. My results support the hypotheses that plasma protein concentration can be indicative of a bird’s body molt (which demands considerable protein for feather synthesis) and degree of habitat urbanization, although future work is needed to determine why protein levels were higher in virus-infected birds.
Heart disease is the leading cause of death in the developed world and often occurs following myocardial infarction. Apelin is an endogenous prepropeptide that has been studied for its role in improving cardiac contractility and vasodilation but suffers from a short half-life in the body. By encasing apelin in a nanoparticle patch, we were able to slowly release apelin to cardiac tissue and observe its effects for one month following induced myocardial infarction surgery in mice. This study demonstrates that the apelin nanoparticles can protect the heart from myocardial-induced heart failure, observing overall improved cardiac function and reduction of fibrotic scarring associated with post-myocardial infarction compared to a nontreated group.
Platelet Rich Plasma (PRP) is an emerging procedure in regenerative medicine that offers a non-surgical minimally invasive way for tissue repair and regeneration. PRP has many different bioactive molecules that are able to influence and help achieve greater recovery and regenerative outcomes. Diet has many effects on platelets and looking at the mechanism in which platelet function and aggregation are affected with different diets shows how they are able to affect PRP therapy. Looking at these mechanisms allows for better physician recommendations for preprocedural diets to optimize efficacy. This paper conducts a systematic review to investigate the influence that diet can have on PRP outcomes. It was shown that high fat diets lower the efficacy of treatment while the Mediterranean diet helps promote platelet function and help efficacy. The future is to look at more diets while also integrating lifestyle choice before treatment for optimal outcomes.
