Increased Milk Yield and Reduced Enteric Methane Concentration on a Commercial Dairy Farm Associated with Dietary Inclusion of Sugarcane Extract (Saccharum officinarum)

(1) Background: The purpose of this study was to assess the influence of a natural sugarcane extract (Polygain™) on milk production, milk composition and methane emissions on a commercial dairy farm. (2) Methods: A three-week baseline was established for lactating Holstein × Friesian animals. Following this baseline period, these animals were fed Polygain™ at 0.25% of their estimated dry matter intake for 3 weeks. Methane concentration in the feed bin was determined at each milking using the Gascard NG Infrared Sensor (Edinburgh Sensors LTD). (3) Results: During the intervention phase milk yield increased significantly from 26.43 kg to 28.54 kg per cow per day, whilst methane emissions and bulk tank somatic cell counts decreased significantly in the intervention phase. For methane concentration, an average of 246 ppm during the baseline periods reduced to an average of 161.09 ppm during the intervention phase. For the bulk tank somatic cell counts, the average was observed at 283,200 during the baseline and reduced to an average value of 151,100 during the intervention phase. (4) Conclusions: The natural sugarcane extract was shown to have the potential to mitigate enteric methane emissions while also increasing production and animal wellbeing outcomes in a commercial dairy setting.

Using 17th century medication for modern diabetes management: Doctors' perceptions of self-medication practices - A qualitative study

Purpose

This study was conducted to explore doctors' perceptions and understanding of the self-medication practices of people living with type 2 diabetes.

Methods

A qualitative research design incorporating 20 semi-structured, face-to-face interviews were conducted with doctors treating people with type 2 diabetes in Mysuru, India, between July 2019 and January 2020. All the interviews were conducted in doctors' clinics, audio-recorded and thematically analyzed.

Results

Three themes were identified from these interviews- i) Doctors' beliefs towards their patients' use of traditional medicine and environmental factors influencing prescription practices, ii) Doctors reported little faith in traditional medicines, iii) Limited strategies implemented by doctors to overcome barriers to self-medications. Doctors reported greater belief in western medications over traditional medications and expressed concern that their patients favored traditional medications over western. Multiple factors such as social media, accessibility of healthcare facilities and pill burden influenced adherence to western medications. Also, lack of knowledge about traditional medications and trust in western medications available under government schemes have influenced prescription practices among doctors. It appears that doctors implemented strategies such as educating patients on the detrimental effects of self-medication and insisting on patients to take only western medications to achieve desired blood glucose levels when managing self-medication practices among people with diabetes.

Conclusion

These results suggest that doctors have limited strategies to implement to prevent self-medication practices among people with diabetes. Increasing knowledge amongst doctors about JAS medication effectiveness and thereby garnering greater trust in generic medications. In addition, efforts should be made to identify the best ways to integrate traditional and western medicine into patient-centered care delivery.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-022-01154-5.

Early Exposure is Necessary for the Lifespan Extension Effects of Cocoa in C. elegans

Background

We previously showed that cocoa, a rich source of polyphenols improved the age-associated health and extended the lifespan in C. elegans when supplemented starting from L1 stage.

Aim

In this study, we aimed to find out the effects of timing of cocoa exposure on longevity improving effects and the mechanisms and pathways involved in lifespan extension in C. elegans.

Methods

The standard E. coli OP50 diet of wild type C. elegans was supplemented with cocoa powder starting from different larval stages (L1, L2, L3, and L4) till the death, from L1 to adult day 1 and from adult day 1 till the death. For mechanistic studies, different mutant strains of C. elegans were supplemented with cocoa starting from L1 stage till the death. Survival curves were plotted, and mean lifespan was reported.

Results

Cocoa exposure starting from L1 stage till the death and till adult day 1 significantly extended the lifespan of worms. However, cocoa supplementation at other larval stages as well as at adulthood could not extend the lifespan, instead the lifespan was significantly reduced. Cocoa could not extend the lifespan of daf-16, daf-2, sir-2.1, and clk-1 mutants.

Conclusion

Early-start supplementation is essential for cocoa-mediated lifespan extension which is dependent on insulin/IGF-1 signaling pathway and mitochondrial respiration.

Oral administration of bovine milk-derived extracellular vesicles induces senescence in the primary tumor but accelerates cancer metastasis

The concept that extracellular vesicles (EVs) from the diet can be absorbed by the intestinal tract of the consuming organism, be bioavailable in various organs, and in-turn exert phenotypic changes is highly debatable. Here, we isolate EVs from both raw and commercial bovine milk and characterize them by electron microscopy, nanoparticle tracking analysis, western blotting, quantitative proteomics and small RNA sequencing analysis. Orally administered bovine milk-derived EVs survive the harsh degrading conditions of the gut, in mice, and is subsequently detected in multiple organs. Milk-derived EVs orally administered to mice implanted with colorectal and breast cancer cells reduce the primary tumor burden. Intriguingly, despite the reduction in primary tumor growth, milk-derived EVs accelerate metastasis in breast and pancreatic cancer mouse models. Proteomic and biochemical analysis reveal the induction of senescence and epithelial-to-mesenchymal transition in cancer cells upon treatment with milk-derived EVs. Timing of EV administration is critical as oral administration after resection of the primary tumor reverses the pro-metastatic effects of milk-derived EVs in breast cancer models. Taken together, our study provides context-based and opposing roles of milk-derived EVs as metastasis inducers and suppressors.

Inhibition of the Renin-Angiotensin System Reduces Gene Expression of Inflammatory Mediators in Adipose Tissue Independent of Energy Balance

Obesity is a growing health problem worldwide. The renin-angiotensin system (RAS) is present in adipose tissue, and evidence suggests that it is involved in both diet-induced obesity and the inflammation associated with obesity. The present experiments determined the effect of (1) different angiotensin-converting enzyme (ACE) inhibitors (captopril, perindopril, enalapril) and angiotensin receptor blockers (ARBs: telmisartan, losartan) on adiposity of mice fed a high-fat diet for 28 days (2); acute treatment with the ACE-inhibitor captopril on gene expression of inflammatory markers in mice fed a high-fat diet (HFD); and (3) short-term (2 days) and chronic (28 days) treatment of ACE-inhibition on energy expenditure (EE) and energy balance in mice fed HFD ad libitum (AL), as well as receiving HFD limited to the amount of calories eaten by controls (pair-fed (PF) group). Body weight, food intake, adiposity and plasma leptin were lower in ACE inhibitor or ARB-treated groups over 28 days compared with HFD untreated mice. Short-term treatment with captopril led to increased EE relative to the level in the PF group. After 28 days, EE was lower in both captopril-treated and PF mice compared with AL, but the effect was greater in the captopril-treated group. Adiponectin was elevated in captopril-treated mice, but not in PF mice, after both 2 and 28 days. Additionally, acute RAS blockade in HFD-fed mice reduced mRNA expression for MCP-1, IL-6, TLR4, and leptin in adipose tissue relative to values in untreated groups. These data demonstrate that ACE inhibition and angiotensin receptor blockade reduce food intake to produce weight loss and suggest that the anti-inflammatory effects of ACE inhibition may be independent of weight loss.

Use of a sensitive multisugar test for measuring segmental intestinal permeability in critically ill, mechanically ventilated adults: A pilot study

BACKGROUND

Increased intestinal permeability (IP) is associated with sepsis in the intensive care unit (ICU). This study aimed to pilot a sensitive multisugar test to measure IP in the nonfasted state.

METHODS

Critically ill, mechanically ventilated adults were recruited from 2 ICUs in Australia. Measurements were completed within 3 days of admission using a multisugar test measuring gastroduodenal (sucrose recovery), small-bowel (lactulose-rhamnose [L-R] and lactulose-mannitol [L-M] ratios), and whole-gut permeability (sucralose-erythritol ratio) in 24-hour urine samples. Urinary sugar concentrations were compared at baseline and after sugar ingestion, and IP sugar recoveries and ratios were explored in relation to known confounders, including renal function.

RESULTS

Twenty-one critically ill patients (12 males; median, 57 years) participated. Group median concentrations of all sugars were higher following sugar administration; however, sucrose and mannitol increases were not statistically significant. Within individual patients, sucrose and mannitol concentrations were higher in baseline than after sugar ingestion in 9 (43%) and 4 (19%) patients, respectively. Patients with impaired (n = 9) vs normal (n = 12) renal function had a higher L-R ratio (median, 0.130 vs 0.047; P = .003), lower rhamnose recovery (median, 15% vs 24%; P = .007), and no difference in lactulose recovery.

CONCLUSION

Small-bowel and whole-gut permeability measurements are possible to complete in the nonfasted state, whereas gastroduodenal permeability could not be measured reliably. For small-bowel IP measurements, the L-R ratio is preferred over the L-M ratio. Alterations in renal function may reduce the reliability of the multisugar IP test, warranting further exploration.

Potential contributions of the methodology to the variability of glycaemic index of foods

Glycaemic index (GI) testing provides a useful point of comparison between carbohydrate sources. For this comparison to be meaningful, the methods used to determine GI values need to be rigorous and consistent between testing events. This requirement has led to increasing standardization of the GI methodology, with an international standard developed in joint consultation with FAO/WHO (ISO 26642:2010) currently the most up to date document. The purpose of this review is to compare the international standard to methods of published studies claiming to have performed a GI test. This analysis revealed that the international standard permits a wide range of choices for researchers when designing a GI testing plan, rather than a single standardized protocol. It has also been revealed that the literature contains significant variation, both between studies and from the international standard for critical aspects of GI testing methodology. The primary areas of variation include; what glucose specification is used, which reference food is used, how much reference food is given, what drink is given during testing, the blood sampling site chosen and what assay and equipment is used to measure blood glucose concentration. For each of these aspects we have explored some of the methodological and physiological implications of these variations. These insights suggest that whilst the international standard has assisted with framing the general parameters of GI testing, further stan-dardization to testing procedures is still required to ensure the continued relevance of the GI to clinical nutrition.

The Effect of Mianserin on Lifespan of Caenorhabditis elegan is Abolished by Glucose

BACKGROUND

The antidepressant Mianserin has been shown to extend the lifespan of Caenorhabditis elegan (C. elegan), a well-established model organism used in ageing research. The extension of lifespan in C. elegan was shown to be dependent on increased expression of the scaffolding protein (ANK3/unc-44). In contrast, antidepressant use in humans is associated with an increased risk of death. The C. elegan elegan in the laboratory are fed Escherichia coli (E. coli), a diet high in protein and low in carbohydrate, whereas a typical human diet is high in carbohydrates. We hypothesized that dietary carbohydrates might mitigate the lifespan-extension effect of mianserin.

OBJECTIVE

To investigate the effect of glucose added to the diet of C. elegan on the lifespan-extension effect of mianserin.

METHODS

Wild-type Bristol N2 and ANK3/unc-44 inactivating mutants were cultured on agar plates containing nematode growth medium and fed E. coli. Treatment groups included (C) control, (M50) 50 μM mianserin, (G) 73 mM glucose, and (M50G) 50 μM mianserin and 73 mM glucose. Lifespan was determined by monitoring the worms until they died. Statistical analysis was performed using the Kaplan-Meier version of the log-rank test.

RESULTS

Mianserin treatment resulted in a 12% increase in lifespan (P<0.05) of wild-type Bristol N2 worms but reduced lifespan by 6% in ANK3/unc-44 mutants, consistent with previous research. The addition of glucose to the diet reduced the lifespan of both strains of worms and abolished the lifespan-extension by mianserin.

CONCLUSION

The addition of glucose to the diet of C. elegan abolishes the lifespan-extension effects of mianserin.

Factors affecting self-medication practices among people living with type 2 diabetes in India- A systematic review

Self-medication practices of type 2 diabetes in India include the use of both traditional and western medications. It is important to understand the factors influencing self-medication. A total of 3257 studies were screened and nine studies (six quantitative and three qualitative) were included. The Hawker tool and Joanna Briggs Institute Critical Appraisal tool were used to assess the quality of studies. The findings of the quantitative studies were descriptively analysed while thematic analysis was performed to identify key themes from the qualitative studies. The analysis indicated that participants had greater trust in traditional medications regardless of their socioeconomic and/or educational backgrounds as these were often recommended by friends and family members. Low cost, ease of availability and perceived lower side effects of traditional medications were some of the factors contributing to greater trust. It is suggested that ongoing management of type 2 diabetes requires stringent policies and regulations in the dispensing of traditional and western medications. Continual education to inform people on the use of self-medications and its possible adverse effects is also required.

Serum zonulin measured by enzyme-linked immunosorbent assay may not be a reliable marker of small intestinal permeability in healthy adults

The association between intestinal permeability (IP) and body composition remains unclear. The gold standard differential sugar-absorption test is arduous to complete, with zonulin being increasingly used as an independent biomarker of IP. This pilot study aimed to explore the association between small IP, zonulin concentrations, and body composition in healthy adults. The urinary lactulose-rhamnose ratio was used to measure small IP. Serum zonulin, lipopolysaccharide (LPS) and high-sensitivity C-reactive protein (hs-CRP) were analyzed in serum. Body composition was measured using dual-energy X-ray absorptiometry and anthropometric measurements were collected. In total, 34 participants were included (12 males, median age 28 years, body mass index 24 kg/m², waist circumference 77cm). No correlation was observed between the lactulose-rhamnose ratio and zonulin (r = -.016, P = .929). The lactulose-rhamnose ratio displayed a strong positive correlation with LPS (n 20, r = .536, P = .018) but did not correlate with body composition measures. Conversely, zonulin displayed a moderate positive correlation with waist circumference (r = .437, P = .042) in female participants and hs-CRP (r = .485, P = .004) in all participants. These findings raise important considerations for the measurement of small IP, warranting exploration in larger powered studies that address the limitations of the present study.

Effects of herbs and spices on blood pressure: a systematic literature review of randomised controlled trials

: Hypertension is a major risk factor for cardiovascular disease, affecting 1 billion people worldwide. Literature suggests some herbs and spices have cardiovascular benefits, such as decreasing blood pressure; yet evidence is inconsistent. This article reviewed randomized controlled trials investigating effects of herbs and spices on blood pressure in normotensive, pre-hypertensive and hypertensive participants. Ovid Medline, Embase, Biological abstracts, CINAHL and Cochrane Collaboration were systematically searched. After inclusion and exclusion criteria were applied, nine articles were included for analysis. Overall, three of the nine studies reported statistically significant results, including one of the two studies on hypertensive participants and two of the six studies on pre-hypertensive participants. The remaining study was conducted on normotensive participants and reported no change in blood pressure. There is evidence to suggest certain herbs and spices can reduce blood pressure in a hypertensive and pre-hypertensive population and may not induce hypotension in a normotensive population.

A High-throughput Assay for the Prediction of Chemical Toxicity by Automated Phenotypic Profiling of Caenorhabditis elegans

Applying toxicity testing of chemicals in higher order organisms, such as mice or rats, is time-consuming and expensive, due to their long lifespan and maintenance issues. On the contrary, the nematode Caenorhabditis elegans (C. elegans) has advantages to make it an ideal choice for toxicity testing: a short lifespan, easy cultivation, and efficient reproduction. Here, we describe a protocol for the automatic phenotypic profiling of C. elegans in a 384-well plate. The nematode worms are cultured in a 384-well plate with liquid medium and chemical treatment, and videos are taken of each well to quantify the chemical influence on 33 worm features. Experimental results demonstrate that the quantified phenotype features can classify and predict the acute toxicity for different chemical compounds and establish a priority list for further traditional chemical toxicity assessment tests in a rodent model.

Spatially and temporally variable urinary N loads deposited by lactating cows on a grazing system dairy farm

Feed nitrogen (N) intakes in Australian grazing systems average 545 g cow^-1 day^-1, indicating that urinary N is likely to be the dominant form excreted. Grazing animals spend disproportionate amounts of time in places on dairy farms where N accumulation is likely to occur. We attached to grazing cows sensors that measure urine volume and N concentration, as well as global positioning systems sensors used to monitor the times the cows spent in different places on a farm and the location of urination events. The cows were monitored for up to 72 h in each of two seasons. More urination events and greater urine volumes per event were recorded in spring 2014 (3.1 L) compared with winter 2015 (1.4 L), most likely influenced by environmental conditions and the greater spring rainfall observed. Mean (range) N concentration (0.71%; 0.02 to 1.52%) and N load (12.8 g cow^-1 event^-1; 0.3 to 64.5 g cow^-1 event^-1) did not differ over the two monitoring periods. However, mean (range) daily N load was greater in spring (277 g cow^-1 day^-1; 200 to 346 g cow^-1 day^-1) than in winter (90 g cow^-1 day^-1; 44 to 116 g cow^-1 day^-1) due to the influence of urine volume. Relatively greater time was spent in paddocks overnight (13.3 h) than in paddocks between morning and evening milking (6.4 h), compared with the mean numbers of urinations in these places (6.4 and 3.8 respectively). The mean N load deposited overnight in paddocks (89.6 g cow^-1) was more than twice that deposited in paddocks during the day (43.8 g cow^-1), due to the greater N load per event overnight, and was more closely linked to the relative difference in time spent in paddocks than in the number of urination events. These data suggest that routinely holding cows in the same paddocks overnight will lead to high urinary N depositions, increasing the potential for N losses from these places. Further research using this technology is required to acquire farm and environment specific urinary data to improve N management.

Determination of maternal pedigree and ewe-lamb spatial relationships by application of Bluetooth technology in extensive farming systems

The objectives of this study were to validate the application of Bluetooth technology to determine maternal pedigree and to determine ewe-lamb spatial relationships in extensive farming systems. A total of 35 first-cross Merino ewes (Merino × Border Leicester and East Friesian) and 23 of their lambs aged 1 to 3 wk were fitted with activity monitors equipped with Bluetooth (BT) technology (ActiGraph wGT3X-BT) by means of halters and collars, respectively. The BT devices on lambs were programmed to receive wireless signals once every minute from nearby BT units on ewes, which were programmed as beacons sending BT signals 4 times every second. Ewes and lambs fitted with sensors were dispatched into the paddocks, and after 10 d, the sensor units were retrieved and the BT signals received by lambs were downloaded using the ActiGraph software. The maternal pedigree of the lambs was determined as the ewe from which the lamb received the most BT signals. The distance between the lamb receiving the signal and the ewe sending the signal was estimated from the strength of BT signal received. The pedigree determined by BT was compared with the pedigree determined by DNA profiling and verification. The results showed that the accuracy of maternal pedigree determined by BT signals reached 100% within the first 15 min of returning animals to pasture of ewes and lambs fitted with sensors. Maternal signals (counts/d) received by 1-, 2-, and 3-wk-old lambs were 617 ± 102, 603 ± 54, and 498 ± 36, respectively, and the corresponding nonmaternal signals received were 140 ± 27, 106 ± 30, and 155 ± 39, respectively. Maternal signals received during the dark period were significantly higher than the maternal signals received during the light period ( < 0.05). Maternal signals received during the light period by 3-wk-old lambs were significantly lower when compared with those received by 1- and 2-wk-old lambs. Over 90% of the BT signals received from within 2 m of the lamb were from its mother. The maternal BT signals expressed as a portion of total BT signals decreased with increasing distance from the lamb. The results show that BT wireless networking is a fast and reliable method for the determination of maternal pedigree of lambs in extensive farming systems. In addition, wireless BT technology is also useful in determining mother-offspring spatial relationships.

Regulation of myostatin expression is associated with growth and muscle development in commercial broiler and DMC muscle

Myostatin is a negative regulator of skeletal muscle growth. Muscle tissue is the largest tissue in the body and influences body growth. Commercial Avian broiler chickens are selected for high growth rate and muscularity. Daweishan mini chickens are a slow growing small-sized chicken breed. We investigated the relations between muscle (breast and leg) myostatin mRNA expression and body and muscle growth. Twenty chickens per breed were slaughtered at 0, 30, 60, 90, 120, and 150 days of age. Body and muscle weights were higher at all times in Avian chickens. Breast muscle myostatin expression was higher in Avian chickens than in Daweishan mini chickens at day 30. Myostatin expression peaked at day 60 in Daweishan mini chickens and expression remained higher in breast muscle. Daweishan mini chickens myostatin expression correlated positively with carcass weight, breast and leg muscle weight from day 0 to 60, and correlated negatively with body weight from day 90 to 150, while myostatin expression in Avian chickens was negatively correlated with carcass and muscle weight from day 90 to 150. The results suggest that myostatin expression is related to regulation of body growth and muscle development, with two different regulatory mechanisms that switch between days 30 and 60.

Segmenting Microscopy Images of Multi-Well Plates Based on Image Contrast

Image segmentation is a key process in analyzing biological images. However, it is difficult to detect the differences between foreground and background when the image is unevenly illuminated. The unambiguous segmenting of multi-well plate microscopy images with various uneven illuminations is a challenging problem. Currently, no publicly available method adequately solves these various problems in bright-field multi-well plate images. Here, we propose a new method based on contrast values which removes the need for illumination correction. The presented method is effective enough to distinguish foreground and therefore a model organism (Caenorhabditis elegans) from an unevenly illuminated microscope image. In addition, the method also can solve a variety of problems caused by different uneven illumination scenarios. By applying this methodology across a wide range of multi-well plate microscopy images, we show that our approach can consistently analyze images with uneven illuminations with unparalleled accuracy and successfully solve various problems associated with uneven illumination. It can be used to process the microscopy images captured from multi-well plates and detect experimental subjects from an unevenly illuminated background.

Quinoa Seed Lowers Serum Triglycerides in Overweight and Obese Subjects: A Dose-Response Randomized Controlled Clinical Trial

Background: Quinoa (Chenopodium quinoa) is a pseudo-cereal originally cultivated in the Andean region. The popularity of its seeds has increased in recent years due to the claims of health benefits and superfood qualities. Studies to date on the health benefits of quinoa have been restricted to animal models, and the results provide weak to moderate evidence to support improved plasma lipid profiles. Clinical trials in humans to examine the claims of health benefits of quinoa are limited to a few prospective studies and one randomized trial carried out in postmenopausal women. To our knowledge, no studies have been conducted in the general population. Objective: The objective of this randomized clinical trial was to investigate the effect of different quinoa doses (25 and 50 g/d) on body composition, serum lipids and hormones, and nutrient intakes in overweight and obese humans. Methods: This was a dose-response randomized, controlled, single-blind trial with a parallel design (1 control and 2 treatment groups) that compared the effect of 25 and 50 g quinoa/d in 50 overweight and obese participants over a 12-wk intervention period. Results: Body composition, nutrient intake, and total, LDL, and HDL cholesterol were not significantly altered by quinoa consumption (P > 0.05). Mean serum triglyceride (TG) concentration was reduced significantly in the 50-g quinoa group from 1.14 to 0.72 mmol/L at 12 wk (P < 0.05). The prevalence of metabolic syndrome (MetS) was also reduced in this group by 70%. No significant changes in TGs were observed in the control and 25-g quinoa groups. The prevalence of MetS was reduced by 40% (from n = 7 at baseline to n = 4 at 12 wk) in the 25-g group. Conclusions: The consumption of 50 g quinoa/d lowers serum TGs in overweight and obese participants and reduces the prevalence of MetS. This trial was registered at clinicaltrials.gov as UTN U1111-1175-470.

Comparison and analysis of Wuding and avian chicken skeletal muscle satellite cells

Chicken skeletal muscle satellite cells are located between the basement membrane and the sarcolemma of mature muscle fibers. Avian broilers have been genetically selected based on their high growth velocity and large muscle mass. The Wuding chicken is a famous local chicken in Yunnan Province that undergoes non-selection breeding and is slow growing. In this study, we aimed to explore differences in the proliferation and differentiation properties of satellite cells isolated from the two chicken breeds. Using immunofluorescence, hematoxylin-eosin staining and real-time polymerase chain reaction analysis, we analyzed the in vitro characteristics of proliferating and differentiating satellite cells isolated from the two chicken breeds. The growth curve of satellite cells was S-shaped, and cells from Wuding chickens entered the logarithmic phase and plateau phase 1 day later than those from Avian chicken. The results also showed that the two skeletal muscle satellite cell lines were positive for Pax7, MyoD and IGF-1. The expression of Pax7 followed a downward trend, whereas that of MyoD and IGF-1 first increased and subsequently decreased in cells isolated from the two chickens. These data indicated that the skeletal muscle satellite cells of Avian chicken grow and differentiate faster than did those of Wuding chickens. We suggest that the methods of breeding selection applied to these breeds regulate the characteristics of skeletal muscle satellite cells to influence muscle growth.

ExoCarta: A Web-Based Compendium of Exosomal Cargo

Exosomes are membranous vesicles that are released by a variety of cells into the extracellular microenvironment and are implicated in intercellular communication. As exosomes contain RNA, proteins and lipids, there is a significant interest in characterizing the molecular cargo of exosomes. Here, we describe ExoCarta (http://www.exocarta.org), a manually curated Web-based compendium of exosomal proteins, RNAs and lipids. Since its inception, the database has been highly accessed (>54,000 visitors from 135 countries). The current version of ExoCarta hosts 41,860 proteins, >7540 RNA and 1116 lipid molecules from more than 286 exosomal studies annotated with International Society for Extracellular Vesicles minimal experimental requirements for definition of extracellular vesicles. Besides, ExoCarta features dynamic protein-protein interaction networks and biological pathways of exosomal proteins. Users can download most often identified exosomal proteins based on the number of studies. The downloaded files can further be imported directly into FunRich (http://www.funrich.org) tool for additional functional enrichment and interaction network analysis.

1-Sarcosine-angiotensin II infusion effects on food intake, weight loss, energy expenditure, and skeletal muscle UCP3 gene expression in a rat model

BACKGROUND

There are a myriad of proteins responsible for modulation of expenditure of energy. Angiotensin II (Ang II) is a vital component of renin-angiotensin system that affects blood pressure and also linked to both cachexia and obesity via fat and muscle metabolism. Previous research suggests that the direct action of Ang II is on the brain, via angiotensin II type 1 receptor protein, affecting food intake and energy expenditure. The objective of the study is to investigate the effect of 1-sarcosine (SAR)-Ang II infusion on energy expenditure and metabolism in a rat model of congestive heart failure cachexia.

METHODS

Adult female rats of the Sprague Dawley strain (n = 33) were used (11 pair-fed control, 12 ad libitum and 10, 1-sarcosine-angiotensin II-infused rats). Body weight, faecal excretion, feed intake (in grams), water intake (in milliliters) and urine excreted were recorded daily. The measurements were recorded in three different periods (4 days prior to surgery, "pre-infusion"; day of surgery and 5 days postsurgery, "infusion period"; days 7 to 14, "recovery" period). Different analytical methods were used to measure energy expenditure per period, uncoupling protein 3 mRNA expression, crude protein and adipose tissue body composition.

RESULTS

During the infusion period, the SAR-Ang II group experienced rapid weight loss (p < 0.05) in comparison to the ad libitum and pair-fed groups. The SAR-Ang II group displayed lower (p < 0.05) body fat content (in percent) than the controls. There was also increased (p < 0.05) uncoupling protein 3 (UCP3) mRNA expression in the SAR-Ang II group and pair-fed group when compared to the controls.

CONCLUSION

In summary, the results suggest that SAR-Ang II infusion impairs appetite and decreases body weight by wasting predominantly adipose tissue, which may be due to elevated energy expenditure via mitochondrial uncoupling (UCP3 protein activity).

Angiotensin-converting enzyme inhibition reverses diet-induced obesity, insulin resistance and inflammation in C57BL/6J mice

AIM

Angiotensin-converting enzyme (ACE) inhibition can reduce the body weight of mice maintained on a high-fat diet. The current study examined the effect of the ACE inhibitor, captopril (CAP), on the reversal of diet-induced obesity (DIO), insulin resistance and inflammation in mice.

MATERIALS AND METHODS

DIO was produced in C57BL/6J male mice (n=30) by maintaining animals on a high-fat diet (w/w 21% fat) for 12 weeks. During the subsequent 12-week treatment period, the animals were allowed access to the high-fat diet and either water containing CAP (0.05 mg ml(-1)) or plain tap water (CON, control).

RESULTS

From the first week of treatment, food intake and body weight decreased in CAP-treated mice compared with CON mice. Both peripheral insulin sensitivity and hepatic insulin sensitivity were improved in CAP-treated mice compared with CON mice. CAP-treated mice had decreased absolute and relative liver and epididymal fat weights compared with CON mice. CAP-treated mice had higher plasma adiponectin and lower plasma leptin levels than CON mice. Relative to CON mice, CAP-treated mice had reduced adipose and skeletal muscle monocyte chemoattractant protein 1 (MCP-1), adipose interleukin-6 (IL-6), toll-like receptor 4 (TLR4) and uncoupling protein 2 (UCP2) mRNA expressions. Furthermore, CAP-treated mice had increased peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), long chain acyl-CoA dehydrogenase (LCAD), hormone sensitive lipase (HSL) and decreased lipoprotein lipase (LPL) mRNA expressions in the liver.

CONCLUSION

The results of the current study indicate that in mice with DIO, CAP treatment reduced food intake and body weight, improved insulin sensitivity and decreased the mRNA expression of markers of inflammation. Thus, CAP may be a viable treatment for obesity, insulin resistance and inflammation.

The β3-adrenergic agonist (BRL35135A) acutely increases oxygen consumption and plasma intermediate metabolites in sheep

There is evidence that an atypical adrenoreceptor subtype is involved in mediating some of the physiological effects of catecholamines, particularly in some adipose tissue sites. Therefore, three experiments were conducted to determine the metabolic and energetic responses to oral administration of the purported β3-agonist BRL35135A in ruminant lambs. The post-prandial increase in O2 consumption (0.109 versus 0.139 L/min) and CO2 production (0.102 versus 0.127 L/min) at 30 min after feeding was greater (P < 0.05) in the lambs receiving 5 mg of the BRL35135A. Treatment × time interactions over the period between –50 and 220 min indicate significant increases in plasma non-esterified fatty acids (P < 0.001), glucose (P < 0.001) and lactate (P = 0.024) in lambs consuming a single oral dose of 5 mg BRL35135A. In a subsequent experiment there were similar interactions over the period between –120 and 1440 min for non-esterified fatty acids (P < 0.001), glucose (P < 0.001) and lactate (P < 0.001) in lambs consuming a lower oral dose of 1 mg BRL35135A. The effects of BRL35135A on plasma non-esterified fatty acids (P = 0.95), glucose (P = 0.84) and lactate (P = 0.68) were not modified by the β1- and β2-adrenergic antagonist alprenolol suggesting that the effects were mediated via β3-adrenergic receptor subtypes. In conclusion, these experiments indicate that BRL35135A is acutely active in sheep when given with feed, as indicated by increases in respiratory gas exchange and plasma metabolite concentrations.

Antagonists of the renin-angiotensin system and the prevention of obesity

In addition to its role as an energy store, adipose tissue also acts as an endocrine organ, synthesizing and secreting hormones and cytokines. This review discusses angiotensin II (Ang-II), the biologically active component of the renin-angiotensin system (RAS). Evidence suggests that a functioning RAS is present in adipose tissue. Animal studies have demonstrated that modifying the amount of Ang-II in the body (eg, using RAS knockout/transgenic animal models or the pharmacological treatment of animal models to prevent the formation or action of Ang-II) directly influences body weight and adiposity. In humans, body fat is correlated with levels of angiotensinogen, a precursor of Ang-II. Thus, the treatment of obesity could be improved through the use of substances that interfere with Ang-II.

The polymorphisms of UCP2 and UCP3 genes associated with fat metabolism, obesity and diabetes

Uncoupling proteins (UCPs) belong to the family of mitochondrial transporter proteins that may uncouple the transport of protons across the inner mitochondrial membrane from electron transport and the synthesis of ATP from ADP, hence generating heat rather than energy. In mammals, more than five family members have been identified, including UCP1, UCP2, UCP3, UCP4 (or BMCP1/UCP5) and UCP5. The UCPs may play an important role in energy homeostasis and have become prominent in the fields of thermogenesis, obesity, diabetes and free-radical biology and have been considered candidate genes for obesity and insulin resistance. They have been as important potential targets for treatment of aging, degenerative diseases, diabetes and obesity. Recently, a series of studies showed the polymorphisms of UCPs gene association with the fat metabolism, obesity and diabetes. This review summarizes data supporting the roles of UCP2 and UCP3 in energy dissipation, as well as the genetic variety association with fat metabolism, obesity and diabetes in humans.

Cell signalling and the hormonal stimulation of the hepatic glycine cleavage enzyme system by glucagon

The glycine cleavage enzyme system (GCS) is found in mitochondria. In liver it is activated by glucagon and other hormones but it is not known how the hormonal signal is transmitted to the mitochondria. We found that the cell-permeant protein phosphatase inhibitor okadaic acid stimulated flux through GCS and could induce a significant increase in the sensitivity of GCS and of glycogenolysis to glucagon. Half-maximal stimulation of GCS by glucagon occurred at 3.2+/-0.6 nM, whereas it was fully activated at 0.3 nM in the presence of 1 microM okadaic acid. The protein kinase A agonist adenosine-3',5'-cyclic monophosphorothioate, Sp isomer (10 microM) stimulated the GCS flux by approx. 100%. This stimulation was inhibited by the protein kinase A antagonist 8-bromoadenosine-3', 5'-cyclic monophosphorothioate, Rp isomer (Rp-8-Br-cAMPS). Although Rp-8-Br-cAMPS significantly inhibited glucagon-stimulated glycogenolysis it had no effect on the glucagon-stimulated GCS flux. These results indicate that a cytoplasmic phosphorylated protein is involved in transmitting glucagon's effect to the mitochondria. However, protein kinase A does not have a necessary role in transmitting glucagon's signal. We also examined the role of protein kinase C because angiotensin II also stimulated flux through GCS. However, the phorbol ester PMA had no effect on either GCS or on glycogenolysis.

Uptake and metabolism of propionate in the liver isolated from sheep treated with glucagon

The uptake and metabolism of propionate in the isolated perfused caudal lobe of the liver and in isolated hepatocytes were examined following treatment of sheep with glucagon or saline. Glucagon or sterile saline was infused at 9.8 micrograms/min for 3 h into the jugular vein and then the caudal lobe of the liver was removed surgically under anaesthesia. The caudal lobe was used either to prepare hepatocytes or in a non-recirculating perfusion experiment. Uptake and metabolism of propionate were studied using [2-14C]propionate. In studies using the non-recirculation perfusion of the caudal lobe of the sheep liver it was shown that the treatment of sheep with glucagon resulted in an increased rate of gluconeogenesis from propionate and in an increased net uptake of propionate by the caudal lobe. The uptake of propionate into the hepatocytes was saturable, concentrative and exhibited a K(m) for propionate of 0.24 (SE 0.07) mM and a maximal rate of uptake (Vmax) of 6.7 (SE 0.6) nmol/mg dry cells per min and was unaffected by glucagon treatment of sheep. After incubation of cells in medium containing 0.5 mM-[2-14C]propionate for 10 min, the rate of gluconeogenesis from propionate was 22% higher in the hepatocytes isolated from glucagon-treated sheep. Concentrations in the medium of 1.35 mM butyrate and 1 mM-caproate inhibited propionate uptake by about 50% and abolished the glucagon-induced stimulation of gluconeogenesis from propionate. The results are consistent with a regulatory role for glucagon in the gluconeogenesis from propionate in the sheep liver.

Hormonal regulation of hepatic glycine oxidation

Hormones which regulate hepatic oxidation of glycine include glucagon, catecholamines and vasopressin. The stimulation of oxidation of glycine by glucagon requires cyclic nucleotidedependent phosphorylation of one or more cytosolic proteins and does not involve mobilization of calcium from intracellular stores. The stimulation of glycine oxidation by catecholamines and vasopressin, on the other hand, appears to involve calcium mobilization. While calcium has direct effect on mitochondrial glycine oxidation, the link between phosphorylation of cytosolic protein(s) and mitochondrial glycine oxidation is not known. The stimulation of glycine oxidation by hormones can be demonstrated in mitochondria isolated from rats treated with hormones prior to sacrifice. Both the effects of glucagon and calcium are evident in isolated mitochondria only when inorganic phosphate is included in the medium. These findings are discussed in relation to the regulation of hepatic glycine oxidation.

Regulation of glycine catabolism in rat liver mitochondria

1. The catabolism of glycine was studied in isolated rat liver mitochondria by measuring release of 14CO2 from [1-14C]-glycine. Incubation of mitochondria in a medium containing 0.5 microM free Ca2+ resulted in an 8-fold increase in the rate of degradation of glycine. Intraperitoneal injection of glucagon (33 or 100 micrograms/100 g body wt.) 25 min before killing of rats also resulted in a 3-fold or 10-fold (depending on dosage) increase in the rate of catabolism of glycine. 2. Both the stimulation by free Ca2+ and that by injection of glucagon in vivo were dependent on phosphate in the incubation medium. This requirement for phosphate was specific, as replacement of phosphate by other permeant anions such as thiocyanate and acetate did not permit the stimulation. The phosphate-dependent stimulation of glycine catabolism by Ca2+ was also evident when mitochondria were incubated in the absence of K+. 3. Mitochondria isolated from rats previously injected with glucagon showed elevated rates of degradation of glycine even in the presence of rotenone, provided that regeneration of NAD+ was affected by providing acetoacetate. 4. Hypo-osmolarity of the medium markedly stimulated the rate of degradation of glycine by mitochondria. Although hypo-osmolarity-induced stimulation of glycine degradation was accompanied by parallel changes in mitochondrial matrix volume, no measurable changes in matrix volume were observed in mitochondria stimulated either by free Ca2+ (0.5 microM) or by injection of glucagon in vivo. Furthermore, Ca2+ stimulated glycine decarboxylation in mitochondria exposed to either hyper-osmolar (410 mosmol) or hypo-osmolar (210 mosmol) conditions. Although hyper-osmolarity decreased and hypo-osmolarity increased matrix volume, stimulation of glycine degradation by Ca2+ was not associated with any further changes in matrix volume. 5. These data demonstrate that the regulation of hepatic glycine oxidation by glucagon and by free Ca2+ is largely independent of changes in mitochondrial matrix volume.

Rapid stimulation of the hepatic glycine-cleavage system in rats fed on a single high-protein meal

Glycine catabolism was studied in isolated rat liver mitochondria by measuring the release of 14CO2 from [1-14C]glycine. Mitochondria isolated from rats fed on a high-protein (60% casein) diet for 5 days showed an enhanced ability to catabolize glycine compared with mitochondria from rats fed on a normal-protein (15% casein) diet. Glycine catabolism was also stimulated in normal protein-fed rats if they ingested a single high-protein meal for 2 h before being killed, thus illustrating the rapid response of the glycine-cleavage system to protein intake. The stimulation of glycine catabolism in rats given a high-protein diet or meal was not evident if the mitochondria were incubated in the absence of P(i) (omitting ADP had no effect on the rate). Mitochondria from high-protein- and normal-protein-fed rats did not differ in their ability to accumulate glycine, a process which occurred far too rapidly to impose a limit on the rate of flux through the glycine-cleavage system. The stimulation of glycine catabolism by high-protein feeding was not associated with a change in mitochondrial matrix volume. Furthermore, mitochondria from rats fed on a high-protein meal maintained an enhanced ability to catabolize glycine compared with those from rats fed on a normal-protein meal when incubated in hypo-osmotic solutions of very low osmolarity. When mitochondria from high-protein- or normal-protein-fed rats were maximally activated by incubation in the presence of 0.25 microM-Ca2+, the rates of glycine catabolism were high, but similar, showing that the stimulation of glycine catabolism by high-protein feeding does not involve an increase in the total capacity of the system. These findings show that hepatic glycine catabolism is stimulated rapidly by high-protein feeding, a response that we suggest is involved in the disposal of the excess glycine in the diet.

Flux through glycine cleavage system in isolated hepatocytes: effects of glucagon, cAMP, and calcium

The hepatic glycine cleavage system (GCS) is the principal route for the metabolism of glycine in mammals. Flux through the GCS in isolated rat hepatocytes was stimulated by about 100% by glucagon (10(-7) M), forskolin (10(-4) M), and dibutyryl cAMP (10(-4) M). The stimulation of flux through the GCS by these agents was accompanied by marked elevation of cellular cAMP levels. A significant correlation was observed between increased cellular cAMP levels induced by glucagon and stimulation of flux through the GCS by glucagon. Exclusion of calcium from the incubation medium reduced the basal flux by 38%, but did not affect the degree of stimulation of flux through the GCS by glucagon. A single intraperitoneal injection of glucagon to rats prior to isolation of hepatocytes resulted in a 76% stimulation of flux through the GCS. These hepatocytes with stimulated flux through the GCS showed reduced sensitivity for further stimulation by glucagon. Half-maximal stimulation of flux through the GCS occurred at 3.8 +/- 1.1 and 8.5 +/- 1.4 nM glucagon in hepatocytes isolated from control and glucagon-injected rats, respectively. We conclude that cAMP is involved in the regulation of flux through the GCS by glucagon.

Stimulation of glycine catabolism in isolated perfused rat liver by calcium mobilizing hormones and in isolated rat liver mitochondria by submicromolar concentrations of calcium

Glucagon stimulates flux through the glycine cleavage system (GCS) in isolated rat hepatocytes (Jois, M., Hall, B., Fewer, K., and Brosnan, J. T. (1989) J. Biol. Chem. 264, 3347-3351. In the present study, flux through GCS was measured in isolated rat liver perfused with 100 nM glucagon, 1 microM epinephrine, 1 microM norepinephrine, 10 microM phenylephrine, or 100 nM vasopressin. These hormones increased flux through GCS in perfused rat liver by 100-200% above the basal rate. The possibility that the stimulation of flux by adrenergic agonists and vasopressin is mediated by increases in cytoplasmic Ca2+ which in turn could regulate mitochondrial glycine catabolism was examined by measuring flux through GCS in isolated mitochondria in the presence of 0.04-2.88 microM free Ca2+. Flux through GCS in isolated mitochondria was exquisitely sensitive to free Ca2+ in the medium; half-maximal stimulation occurred at about 0.4 microM free Ca2+ and maximal stimulation (7-fold) was reached when the free Ca2+ in the medium was 1 microM. The Vmax (nanomoles/mg protein/min) and Km (millimolar) values for the flux through GCS in intact mitochondria were 0.67 +/- 0.16 and 20.66 +/- 4.82 in the presence of 1 mM [ethylenebis(oxyethylenenitrilo)]tetraacetic acid and 3.28 +/- 0.76 and 10.98 +/- 1.91 in presence of 0.5 microM free Ca2+, respectively. The results show that the flux through GCS is sensitive to concentrations of calcium which would be achieved in the cytoplasm of hepatocytes stimulated by calcium-mobilizing hormones.

Regulation of hepatic glycine catabolism by glucagon

Glucagon stimulates 14CO2 production from [1-14C] glycine by isolated rat hepatocytes. Maximal stimulation (70%) of decarboxylation of glycine by hepatocytes was achieved when the concentration of glucagon in the medium reached 10 nM; half-maximal stimulation occurred at a concentration of about 2 nM. A lag period of 10 min was observed before the stimulation could be measured. Inclusion of beta-hydroxybutyrate (10 mM) or acetoacetate (10 mM) did not affect the magnitude of stimulation suggesting that the effects of glucagon were independent of mitochondrial redox state. Glucagon did not affect either the concentration or specific activity of intracellular glycine, thus excluding the possibilities that altered concentration or specific activity of intracellular glycine contributes to the observed stimulation. The stimulation of decarboxylation of glycine by glucagon was further studied by monitoring 14CO2 production from [1-14C]glycine by mitochondria isolated from rats previously injected with glucagon. Glycine decarboxylation was significantly stimulated in the mitochondria isolated from the glucagon-injected rats. We suggest that glucagon is a major regulator of hepatic glycine metabolism through the glycine cleavage enzyme system and may be responsible for the increased hepatic glycine removal observed in animals fed high-protein diets.

Effects of exogenous growth hormone on milk production and nutrient uptake by muscle and mammary tissues of dairy cows in mid-lactation

Responses to exogenous growth hormone were measured in lactating dairy cows surgically prepared to allow measurement of nutrient exchanges across mammary and hind-limb muscle tissues. Cows were injected daily with either saline or growth hormone, at a dose of 0.1 mg/kg liveweight, over periods of 6 days. During administration of growth hormone milk yield, milk fat content and yields of milk fat protein and lactose increased. Arterial plasma concentrations of glucose and non-esterified fatty acids were increased, uptake of glucose by leg muscle tissue decreased, lactate release from leg muscle tended to increase, mammary uptake of non-esterified fatty acids increased, blood flow to leg muscle tended to increase and blood flow to mammary tissue increased during injection of growth hormone. The results show that growth hormone affects supply to and utilization of key nutrients by tissues, resulting in the supply to the mammary gland of additional precursors for milk synthesis.