The Research, Advising, and Mentoring Professional: A Unique Approach to Supporting Underrepresented Students in Biomedical Research.

As a pilot intervention strategy to support undergraduate students, especially rural and Alaska Native students who are pursuing biomedical science research and career trajectories, we have developed a unique, mid-level Research, Advising, and Mentoring Professional (RAMP) position. In this article we outline the reasons for creating this position, RAMP qualifications, training, duties, and differences between RAMP and other positions typically found in higher education. Additionally, we discuss the evolution of the position and why it may be of interest to other institutions as they address similar issues involving students from underrepresented groups. Preliminary survey and focus group data from students mentored directly by RAMPs indicated that the holistic advising approach of RAMPs has had a positive impact on student experiences by supporting persistence in degree programs and providing psychosocial support of both personal and professional development.

Supplementation of diets with bovine colostrum influences immune function in dogs.

While the need for colostrum in neonates is well established, the systemic effect of feeding bovine colostrum (BC) to adult humans is gaining increasing attention. However, no systematic studies evaluating the immunomodulatory effect of BC in dogs have been reported. The aim of the present study was to evaluate the immunomodulatory effect of dietary supplementation of BC in dogs. The study was conducted in two phases: pre-test (8 weeks) and test (40 weeks), with twenty-four dogs (mean age 2.5 years) randomised into two groups. In the 'pre-test' phase, both groups were fed a nutritionally complete diet. At the end of the 'pre-test' phase, all dogs received a canine distemper virus (CDV) vaccine, and dogs in the 'test group' were switched to a diet supplemented with 0.1% spray-dried BC. Response to the CDV vaccine was evaluated by measuring vaccine-specific plasma IgG levels. Gut-associated lymphoid tissue response was assessed by measuring faecal IgA levels. Gut microbiota were evaluated by the temporal temperature gel electrophoresis methodology. Dogs fed the BC-supplemented diet demonstrated a significantly higher vaccine response and higher levels of faecal IgA when compared with the control group. Supplementing diets with BC also resulted in significantly increased gut microbiota diversity and stability in the test group. In conclusion, diets supplemented with BC significantly influence immune response in dogs.

Supplementation of Diets With Spirulina Influences Immune and Gut Function in Dogs.

Spirulina refers to two species of blue green algae (Arthrospira platensis, and A. maxima) consumed by humans as food for centuries. While, Spirulina has been shown to have immune enhancing properties in several animal and human studies, there are no systematic studies in dogs. The aim of this study was to evaluate the immunomodulatory effect of dietary supplementation with Spirulina in dogs. The study was conducted in two phases: Pre-test (8 wks.) and Test (42 wks.). Thirty adult dogs (mean 2.9 yrs.) were randomized into two groups and fed a nutritionally complete diet in the "Pre-test" phase. At the end of "Pre-test" phase all dogs received a rabies vaccine, and dogs in "test group" were switched to diet supplemented with dried Arthrospira platensis (Spirulina). Response to rabies vaccine was evaluated by Rapid Fluorescent Focus Inhibition Test (RFFIT). Gut immune response was assessed by measuring fecal IgA. Gut microbiota was evaluated by Temporal Temperature Gel Electrophoresis (TTGE) methodology. Repeated measures ANOVA was used to test for differences between groups and statistical significance considered to be p < 0.05. Dogs fed diets supplemented with Spirulina demonstrated enhanced immune status by showing significantly higher vaccine response and higher levels of fecal IgA as compared to the control group. Supplementing diets with Spirulina also resulted in significantly increased gut microbiota stability in the test group. In conclusion, diets supplemented with Spirulina significantly enhanced immune response and gut health in dogs.

Sled dogs as a model for PM2.5 exposure from wildfires in Alaska.

Particulate matter 2.5 (PM2.5) exposure induces oxidative stress associated with many negative health outcomes such as respiratory disorders, cardiovascular disease and neurodegenerative disease. Research shows that diet and exercise can improve antioxidant defense against oxidative stress. This study is the first to use an Arctic animal model to investigate the cumulative effects of two lifestyle interventions on the antioxidant response before, during, and after ambient PM 2.5 exposure from wildfire: antioxidant supplementation (Arthrospira platensis) and exercise. In a two-factorial, longitudinal design, this study divided sled dogs (n = 48) into four groups (exercise and supplemented, exercise, supplemented, and control) to (1) test the effects of a 30-day exercise and antioxidant supplementation protocol on antioxidant response; and (2) measure the antioxidant response of all groups during and after a natural wildfire event. Commercial assays for total antioxidant power (TAP) and the enzymatic antioxidant superoxide dismutase (SOD) were used as markers for antioxidant status and response. During the forest fire, SOD was increased 5- to 10-fold over pre/post-exposure levels in all groups suggesting an endogenous upregulation of defense systems in response to the acute environmental stress. TAP was lower in all groups at peak PM2.5 exposure compared to 48 h after peak exposure in all groups except the exercise alone group which may indicate that exercise offers improved endogenous defense.

Baseline Characteristics of the 2015-2019 First Year Student Cohorts of the NIH Building Infrastructure Leading to Diversity (BUILD) Program.

Objective: The biomedical/behavioral sciences lag in the recruitment and advancement of students from historically underrepresented backgrounds. In 2014 the NIH created the Diversity Program Consortium (DPC), a prospective, multi-site study comprising 10 Building Infrastructure Leading to Diversity (BUILD) institutional grantees, the National Research Mentoring Network (NRMN) and a Coordination and Evaluation Center (CEC). This article describes baseline characteristics of four incoming, first-year student cohorts at the primary BUILD institutions who completed the Higher Education Research Institute, The Freshmen Survey between 2015-2019. These freshmen are the primary student cohorts for longitudinal analyses comparing outcomes of BUILD program participants and non-participants. Design: Baseline description of first-year students entering college at BUILD institutions during 2015-2019. Setting: Ten colleges/universities that each received <$7.5mil/yr in NIH Research Project Grants and have high proportions of low-income students. Participants: First-year undergraduate students who participated in BUILD-sponsored activities and a sample of non-BUILD students at the same BUILD institutions. A total of 32,963 first-year students were enrolled in the project; 64% were female, 18% Hispanic/Latinx, 19% African American/Black, 2% American Indian/Alaska Native and Native Hawaiian/Pacific Islander, 17% Asian, and 29% White. Twenty-seven percent were from families with an income <$30,000/yr and 25% were their family's first generation in college. Planned Outcomes: Primary student outcomes to be evaluated over time include undergraduate biomedical degree completion, entry into/completion of a graduate biomedical degree program, and evidence of excelling in biomedical research and scholarship. Conclusions: The DPC national evaluation has identified a large, longitudinal cohort of students with many from groups historically underrepresented in the biomedical sciences that will inform institutional/national policy level initiatives to help diversify the biomedical workforce.

One health in the circumpolar North.

The North faces significant health disparities, especially among its many Indigenous peoples. In this article we discuss historical, environmental, and cultural variables that contribute to these disparities and propose a One Health approach to address them in a holistic and culturally appropriate manner. The One Health paradigm recognizes the interdependence among the health and well-being of people, animals and the environment. As such, the framework aligns well with many Indigenous world views. This proactive, interdisciplinary, constructivist, and collaborative approach promise earlier detection of risks and threats, as well as more effective responses, in part by engaging community level stakeholders in all stages of the process. In the far North, humans, especially Indigenous peoples, continue to live closely connected to their environment, in settings that exert significant impacts on health. In recent decades, rapid warming and elevated contaminant levels have heightened environmental risks and increased uncertainty, both of which threaten individual and community health and well-being. Under these circumstances especially, One Health's comprehensive approach may provide mitigating and adaptive strategies to enhance resilience. While many of the examples used in this manuscript focus on Alaska and Canada, the authors believe similar conditions exist among the indigenous and rural residents across the entire Circumpolar North.

Disentangling factors that shape the gut microbiota in German Shepherd dogs.

The aim of this study was to explore the development of the gut microbiota in 168 German Shepherd dogs (30 litters) from 7 weeks to 18 months of age and furthermore, to study the effect of relatedness, maternal microbiota composition and living environment in a large and well-defined population of dogs. Using 454 pyrosequencing, we assessed the effects of pre- and postnatal probiotic supplementation (Lactobacillus johnsonii NCC533 (La1)) and analysed whether administration of the probiotic strain influenced fecal microbiota composition in a placebo controlled double-blinded study. The bitches were treated with probiotics or placebo during last trimester of pregnancy and until their puppies were 8 weeks old, the puppies received the same treatment as their mothers between 3-12 weeks of age. Samples from bitches were collected at pregnancy day 42, partum, 4 weeks postpartum and 7 weeks postpartum and from puppies at the age 4 weeks, 7 weeks, 12-13 months and 15-18 months. Serum IgA, total serum IgE, fecal IgA and IgG antibody responses against canine distemper virus were analysed by ELISA in order to detect any immune stimulating effects of the probiotic strain. Analysis of the fecal microbiota composition showed that the predominant phyla were the same in 7 weeks old puppies as in pregnant and lactating bitches (Firmicutes, Fusobacteria, Bacteroidetes). Proportions among different bacteria as well as diversity varied from 7 weeks old puppies up to 15-18 months of age. Litter mates had a more similar fecal microbiota compared to unrelated dogs and 7 weeks old puppies were more similar to their mothers than to unrelated bitches at 7 weeks postpartum but not at partum. We observed a change in the relative abundance of different bacteria during lactation, and an increase in diversity from pregnancy to end of lactation. The microbial diversity was affected by living area where dogs living in big cities had higher diversity compared to dogs living at the countryside. However, we were not able to demonstrate an effect by pre and postnatal exposure to Lactobacillus johnsonii NCC533 (La1) upon the diversity or composition of the microbiota or the levels of serum IgA, total serum IgE, fecal IgA or vaccine response. Our findings provide a better understanding of the canine fecal microbiota in growing dogs as well as in pregnant and lactating bitches. This information forms a basis for further research on the connection between early gut colonization and immune function later in life.

Exercise Increases Glucose Transporter-4 Levels on Peripheral Blood Mononuclear Cells.

PURPOSE: Glucose transporter 4 (GLUT4) plays a key role in the pathophysiology of type 2 diabetes. Glucose transporter 4 is upregulated in response to exercise, enhancing cellular glucose transport in skeletal muscle tissue. This mechanism appears to remain intact in individuals with insulin resistance. Details of the mechanism are poorly understood and are challenging to study due to the invasive nature of muscle biopsy. Peripheral blood mononuclear cells (PBMC) have documented insulin-sensitive GLUT4 activity and may serve as a proxy tissue for studying skeletal muscle GLUT4. The purpose of this study was to investigate whether GLUT4 in PBMC is affected by conditioning. METHODS: We recruited 16 student athletes from the cross-country running and skiing teams and fifteen sedentary students matched for age and sex from the University of Alaska Fairbanks. Peripheral blood mononuclear cells were collected with mononuclear cell separation tubes. The GLUT4 concentrations were measured using a commercially available enzyme linked immunosorbent assay. Additionally, correlations between PBMC GLUT4 and common indicators of insulin resistance were examined. RESULTS: Results indicate significantly higher PBMC GLUT4 levels in conditioned athletes than in their sedentary counterparts, similar to what has been documented in myocytes. Females were observed to have higher PBMC GLUT4 levels than males. Correlations were not detected between PBMC GLUT4 and hemoglobin A1c, glucose, insulin, homeostatic model assessment of insulin resistance, body mass index, or body fat. CONCLUSIONS: This study provides evidence to support exploration of PBMC as a proxy tissue for studying GLUT4 response to exercise or other noninsulin factors.

Hair analysis in sled dogs (Canis lupus familiaris) illustrates a linkage of mercury exposure along the Yukon River with human subsistence food systems.

The dog has been an important biomedical research model and hair samples from sled dogs could be used as a biomarker of exposure to metals. Hair samples were used as a non-invasive indicator of mercury exposure in sled dogs fed commercial food and traditional village diets. Sled dog populations living in rural New York and Alaska were sampled in 2005 and 2006. Total mercury (THg) content was determined on the entire hair sample in sled dogs from reference sites in North Creek, New York and Salcha Alaska. Both sites fed a commercial feed for high performance dogs and had mean THg levels of 36.6 ng/g for New York sled dogs while Alaskan sled dogs, occasionally supplemented with fish oil showed THg mean of 58.2 ng/g. These THg levels are below levels that are suggested to cause adverse effects and should be considered baseline levels. Yukon River sled dogs had higher THg, ranging from 139 to 15,800 ng/g and showed decreasing mean levels from the delta area to upriver. There were significant differences between THg in the dogs from Russian Mission (10,908.3+/-3028 ng/g), the farthest west village, and Ft. Yukon (1822.4+/-1747 ng/g), the farthest east village. All village dogs along the Yukon had higher THg levels than the THg mean level (657+/-273 ng/g) of hair from ancient dogs of the Seward Peninsula.

25(OH)D levels in trained versus sedentary university students at 64° north.

PURPOSE: 25-hydroxyvitamin D (25[OH]D) deficiency is associated with compromised bone mineralisation, fatigue, suppressed immune function and unsatisfactory skeletal muscle recovery. We investigated the risk of 25(OH)D insufficiency or deficiency in endurance athletes compared to sedentary non-athletes living at 64° north. METHODS: University student-athletes (TS) and sedentary students (SS) volunteered to participate in this study. TS engaged in regular exercise while SS exercised no more than 20 minutes/week. Metabolic Equivalent of Task (MET) scores for participants were determined. Vitamin D intake was assessed using the National Cancer Institute's 24-hour food recall (ASA24). Fasting plasma 25(OH)D levels were quantified via enzyme-linked immunosorbent assay. RESULTS: TS reported higher activity levels than SS as assessed with MET-minutes/week and ranking of physical activity levels (p < 0.05). The reported mean daily intake of vitamin D was higher in TS compared to SS (p < 0.05) while 25(OH)D plasma levels were lower in TS than in SS (p < 0.05). In total, 43.8% of the TS were either insufficient (31.3%) or deficient (12.5%) in 25(OH)D, while none of the SS were insufficient and 13.3% were deficient. CONCLUSION: TS are at increased risk of 25(OH)D insufficiency or deficiency compared to their sedentary counterparts residing at the same latitude, despite higher vitamin D intake.

BUILDing BLaST: promoting rural students' biomedical research careers using a culturally responsive, one health approach.

BACKGROUND AND PURPOSE: Most postsecondary institutions in the state of Alaska (USA) have a broad mission to serve diverse students, many of whom come from schools in rural villages that are accessible only by plane, boat, or snowmobile. The major research university, the University of Alaska in Fairbanks (UAF), serves a population whereby 40% are from groups recognized as underrepresented in the biomedical workforce. The purpose of this article is to describe the Building Infrastructure Leading to Diversity (BUILD)-supported program in the state of Alaska that seeks to engage students from rural areas with a culturally relevant approach that is centered on the One Health paradigm, integrating human, animal, and environmental health. PROGRAM AND KEY HIGHLIGHTS: The Biomedical Learning and Student Training (BLaST) program distinguished by broad themes that address recruitment, retention, and success of students in biomedical programs, especially for students from rural backgrounds. Targeted rural outreach emphasizes that biomedical research includes research on the integration of human, animal, and environmental health. This One Health perspective gives personal relevance and connection to biomedical research. This outreach is expected to benefit student recruitment, as well as foster family and community support for pursuit of college degrees. BLaST promotes integration of research into undergraduate curricula through curriculum development, and by creating a new class of instructors, laboratory research and teaching technicians, who provide research mentorship, course instruction, and comprehensive advising. Finally, BLaST facilitates early and sustained undergraduate research experiences in collaborations with graduate students and faculty. IMPLICATIONS: BLaST's approach is highly adapted to the Alaskan educational and physical environment, but components and concepts could be adapted to other rural areas as a means to engage students from rural backgrounds, who often have a closer relationship with the natural environment than urban students.

Immunoglobulins in dogs: correspondence and maturation in 15 litters of German shepherd dogs and their dams.

Some dog breeds, including the German shepherd dog (GSD), are predisposed to immune-related disorders. The authors prospectively described development of serum and faecal IgA and serum IgE in GSD from puppies until adulthood and the relationship between mothers and their offspring. Further, the authors tested whether dogs with lower serum IgA also have low faecal IgA and/or serum IgE. To reveal whether any of the parameters could be proven to influence the immune response, the authors also measured serum IgG against canine distemper virus (CDV). To test their hypothesis, the authors used linear mixed models to investigate the relationship of serum IgA, serum IgE and faecal IgA levels in litters and their mothers. Fifteen GSD bitches beginning at 42 days of pregnancy and subsequently all of their offspring (n=83 puppies), reared under well-controlled conditions, were included. All dogs came from the kennel of the Swedish Armed Forces. Serum IgE, serum IgA and faecal IgA levels were lower in seven-week-old puppies than at one year of age. There was no relationship in Ig concentrations between bitches and their puppies at seven weeks of age. Dogs with higher faecal IgA had higher IgG titres against CDV, indicating a favourable systemic immune status.

Effects of postexercise feeding of a supplemental carbohydrate and protein bar with or without astaxanthin from Haematococcus pluvialis to exercise-conditioned dogs.

OBJECTIVE: To characterize the postprandial nutrient profiles of exercise-conditioned dogs fed a supplemental carbohydrate and protein bar with or without astaxanthin from Haematococcus pluvialis immediately after exercise. ANIMALS: 34 exercise-conditioned adult Husky-Pointer dogs. PROCEDURES: The study had 2 phases. During phase 1, postprandial plasma glucose concentration was determined for dogs fed a bar containing 25% protein and 18.5% or 37.4% maltodextrin plus dextrin (rapidly digestible carbohydrate; RDC), or dry kibble (30% protein and 0% RDC) immediately after exercise. During phase 2, dogs were exercised for 3 days and fed a bar (25% protein and 37.4% RDC) with (CPA; n = 8) or without (CP; 8) astaxanthin or no bar (control; 8) immediately after exercise. Pre- and postexercise concentrations of plasma biochemical analytes and serum amino acids were determined on days 1 and 3. RESULTS: Phase 1 postexercise glucose concentration was increased when dogs were provided the 37.4% RDC bar, but not 0% or 18.5% RDC. On day 3 of phase 2, the CPA group had the highest pre-exercise triglyceride concentration and significantly less decline in postexercise glucose concentration than did the CP and control groups. Mean glucose concentration for the CP and CPA groups was significantly higher than that for the control group between 15 and 60 minutes after bar consumption. Compared to immediately after exercise, branched-chain amino acid, tryptophan, leucine, and threonine concentrations 15 minutes after exercise were significantly higher for the CP and CPA groups, but were lower for the control group. CONCLUSIONS AND CLINICAL RELEVANCE: Dogs fed a bar with 37.4% RDCs and 25% protein immediately after exercise had increased blood nutrient concentrations for glycogen and protein synthesis, compared with control dogs.

Glucose transporter-4 in white blood cells of young and old sled dogs: a model for human biomarker development.

The insulin responsive glucose transporter, GLUT4 is found predominantly in muscle and adipose cells. Maratou and others (2007) reported that there is GLUT4 in white blood cells (WBC) collected from human subjects in response to insulin activation. This study was designed to validate the presence of GLUT4 in white blood cells of sled dogs and furthermore to investigate whether changes in levels of the GLUT4 protein might be associated with aging. Additionally, we examined the blood insulin concentration of two populations of dogs, young and old, before and after a meal to observe their insulin response. It is documented in skeletal muscle that GLUT4 expression is increased as a result of conditioning, making sled dogs an excellent model in the circumpolar north for studying the effects of exercise, nutrition and diabetes (Felsburg 2002; Kararli 2006). Blood was withdrawn from 11 healthy sled dogs: 6 young (1-5 years) and physically fit, conditioned for racing and 5 old (7-13 years), retired from racing. The insulin response was determined using blood plasma and ELISA. The buffy coat (containing WBC) was collected with a glass pipette after centrifugation and washed and suspended in 1x phosphate buffer. GLUT4 was measured using ELISA kits (USCN Life Sciences). The results validate that GLUT4 is present in white blood cells in sled dogs. Age had no significant effect in the concentration of GLUT4 between the populations of old and young dogs. A significant difference in insulin levels pre and post meal in young (0.13 ± 0.03 ng/mL (pre), 0.22 ± 0.04 ng/mL (post), p < 0.05) and old (0.13 ± 0.02 ng/mL (pre), 0.22 ± 0.03 ng/mL (post), p < 0.05) dogs was observed, displaying the typical postprandial insulin spike. No significant difference was found in insulin concentration comparing old versus young dogs. Our data shows that white blood cells in young (40.4 ± 2.4 ng/mL) and old (35.3 ± 8.8 ng/mL) sled dogs have quantifiable but non-significant different GLUT4 levels (p > 0.05). Detecting GLUT4 via an ELISA in white blood cells, opens up minimally invasive avenues for studying the underlying molecular mechanisms associated with insulin resistance in more complex, dynamic and physiological systems. This project was the first step in developing a protocol for this simple, technique with a potential clinical application for diagnosing insulin resistance.

The effect of acute exercise on GLUT4 levels in peripheral blood mononuclear cells of sled dogs.

Using sled dogs as exercise model, our objectives of this study were to 1) assess the effects of one acute bout of high-intensity exercise on surface GLUT4 concentrations on easily accessible peripheral blood mononuclear cells (PBMC) and 2) compare our findings with published research on exercise induced GLUT4 in skeletal muscle. During the exercise bout, dogs ran 5 miles at approximately 90% of VO2 max. PMBC were collected before exercise (baseline), immediately after exercise and after 24h recovery.GLUT4 was measured via ELISA. Acute exercise resulted in a significant increase on surface GLUT4 content on PBMC. GLUT4 was increased significantly immediately after exercise (~ 50%; p<0.05) and reduced slightly by 24h post-exercise as compared to baseline (~ 22%; p>0.05). An effect of acute exercise on GLUT4 levels translocated to the cell membrane was observed, with GLUT4 levels not yet returned to baseline after 24h post-exercise. In conclusion, the present investigation demonstrated that acute high-intensity exercise increased GLUT4 content at the surface of PBMC of sled dogs as it has been reported in skeletal muscle in other species. Our findings underline the potential use of peripheral blood mononuclear cell GLUT4 protein content as minimally invasive proxy to investigate relationships between insulin sensitivity, insulin resistance, GLUT4 expression and glucose metabolism.

Biochemical and metabolic changes due to exercise in sprint-racing sled dogs: implications for postexercise carbohydrate supplements and hydration management.

Evaluations of biochemical changes associated with spring-style sled dog racing indicate that differences in cortisol, lactate, and serum glucose levels suggest exercise of moderate duration (but high intensity) has metabolic demands that dif-fer from those for typical endurance sled dog racing. Additionally, hematocrit, albumin, sodium, chloride, and blood urea nitrogen levels decreased in one team of dogs, whereas there were mild increases in sodium, chloride, and blood urea nitrogen in the other team. These opposing biochemical findings suggest physiologic changes associated with differences in hydration status, likely attributed to different dietary and hydration strategies used by the respective kennels.

Effects of post-exercise supplements on glycogen repletion in skeletal muscle.

Post-exercise carbohydrate supplementation has been routinely used to enhance glycogen concentrations in skeletal muscle, particularly during multiple-day athletic events. Consumption of protein hydrolysates mixed with carbohydrate supplements during the post-exercise period may increase insulin response and cause glycogen repletion in skeletal muscle. A group of Alaskan sled dogs were selected to examine post-exercise supplementation in a paired crossover study design. The dogs were subjected to the same exercise regimen and provided one of three treatments-water, glucose polymers, or glucose polymers with protein hydrolysates-over a 2-month period. Parameters tested at various post-exercise time points included plasma insulin, glucagon and glucose concentrations, and skeletal muscle glycogen content to gain a better understanding of glucose metabolism and glycogen repletion. The results showed an enhanced insulin, glucose, and glucagon response immediately after supplementation and significantly increased glycogen concentrations in skeletal muscle within 24 hours when dogs received either of the glucose-containing supplements compared with water alone. There were no differences in the plasma parameters or skeletal muscle glycogen stores in dogs provided the glucose polymers alone or the glucose polymers plus protein hydrolysates. Thus, post-exercise carbohydrate supplementation increased muscle glycogen repletion, but inclusion of protein hydrolysates in the supplements provided no additional benefits.

Conditioning causes an increase in glucose transporter-4 levels in mononuclear cells in sled dogs.

This study was designed to investigate the effects of physical conditioning on the expression of the insulin sensitive glucose transporter-4 protein (GLUT4) on mononuclear cells and HOMA-IR levels in dogs and compared to results reported in human skeletal muscle and the skeletal muscle of rodent models. Blood was sampled from conditioned dogs (n = 8) and sedentary dogs (n = 8). The conditioned dogs were exercised four months prior the experiment and were following a uniform training protocol, whereas the sedentary dogs were not. GLUT4 expression in mononuclear cells and plasma insulin levels were measured using commercially available enzyme-linked immunosorbent assay (ELISA). Blood glucose levels were determined using blood plasma. HOMA-IR was calculated using plasma insulin and blood glucose levels using the linear approximation formula. Our results indicate that the state of conditioning had a significant effect on the GLUT4 expression at the surface of mononuclear cells. HOMA-IR was also affected by conditioning in dogs. GLUT4 levels in mononuclear cells of sled dogs were inversely correlated with the homeostasis model assessment of insulin sensitivity. This study demonstrates that conditioning increases GLUT4 levels in mononuclear cells of sled dogs as it has been previously reported in skeletal muscle. Our results support the potential of white blood cells as a proxy tissue for studying insulin signaling and may lead to development of a minimally invasive and direct marker of insulin resistance. This may be the first report of GLUT4 in mononuclear cells in response to exercise and measured with ELISA.

Milk oligosaccharides over time of lactation from different dog breeds.

The partnership of humans and dogs goes back to over 10'000 years, yet relatively little is known about a dog's first extra-uterine nutrition particularly when it comes to milk oligosaccharides. We set out to identify and quantify milk oligosaccharides over the course of lactation from different dog breeds (Labrador retriever, Schnauzer and 3 Alaskan husky crossbreeds). To this end, 2 different chromatographic methods with fluorescence and mass spectrometry detection were developed and one was validated for quantification. Besides lactose and lactose-sulphate, we identified 2 different trisaccharides composed of 3 hexose units, 3'sialyllactose (3'SL), 6'sialyllactose (6'SL), 2'fucosyllactose (2'FL), and a tetrasaccharide composed of 2 hexoses, an N-acetylhexosamine and a deoxyhexose. 3'SL was present at the highest levels in milk of all dog breeds starting at around 7.5 g/L and dropping to about 1.5 g/L in the first 10 days of lactation. 6'SL was about 10 times less abundant and 2'FL and the tetrasaccharide had rather varying levels in the milk of the different breeds with the tetrasaccharide only detectable in the Alaskan husky crossbreeds. The longitudinal and quantitative data of milk oligosaccharides from different dog breeds are an important basis to further our understanding on their specific biological roles and also on the specific nutritional requirements of lactating puppies.

Mercury interferes with endogenous antioxidant levels in Yukon River subsistence-fed sled dogs.

Before adopting modern corn-and-grain-based western processed diets, circumpolar people had a high fat and protein subsistence diet and exhibited a low incidence of obesity, diabetes and cardiovascular disease. Some health benefits are attributable to a subsistence diet that is rich in omega-3 fatty acids and antioxidants. Pollution, both global and local, is a threat to wild foods, as it introduces contaminants into the food system. Northern indigenous people and their sled dogs are exposed to a variety of contaminants, including mercury, that accumulate in the fish and game that they consume. The sled dogs in Alaskan villages are maintained on the same subsistence foods as their human counterparts, primarily salmon, and therefore they can be used as a food systems model for researching the impact of changes in dietary components. In this study, the antioxidant status and mercury levels were measured for village sled dogs along the Yukon River. A reference kennel, maintained on a nutritionally balanced commercial diet, was also measured for comparison. Total antioxidant status was inversely correlated with the external stressor mercury.