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This work aims to present the results of evaluating the coloristic properties of polylactic acid (PLA) fibers. PLA is common nowadays in much research, as it is a biodegradable plastic from renewable sources. However, little research is devoted to PLA fibers, and even less to applied research of colored fibers. The prepared color masterbatches, created using inorganic pigments, such as titanium dioxide and carbon black, were subsequently used to prepare dyed PLA fibers in mass. The fibers were drawn to the maximum drawn ratio. The properties of the pure and dyed fibers were investigated before and after accelerated light aging using Q-SUN equipment. The changes were recorded by Fourier Transform Infrared (FTIR) spectroscopy and colorimetric properties were recorded using a device spectrometer from TECHKON SpectroDens. We also evaluated thermal properties from the first heating via differential scanning calorimetry (DSC). The measurements were taken before and after the aging of the PLA fibers, in order to see the effect of aging on the supermolecular structure, excluding the influence of the preparation process and the influence of the kind of PLA. Using inorganic pigments showed sufficient color stability even after accelerated light aging, which is beneficial for using colored fibers in practice.

In the past, mill races were part of the urban structure of many towns in Slovakia. As regulated and artificially created waterways, they served to drive mills, rollers, or hammers. With the use of new sources of energy, they lost their functions, and most of them were dried, filled, or buried underground. In our research, we examine the former mill race corridor in Podolínec (Prešov region, Slovakia) and its potential to contribute to urban regeneration strategies. The research steps included the following, namely 1. Identification of the route of the mill race corridor according to historical sources, 2. survey of its current state and its spatial preservation in the urban structure, 3. evaluation of the possibilities of its new uses, which could increase the quality and attractiveness of urban public spaces. The research results show that the fragments of the corridor of the extinct mill race are still identifiable in the urban fabric, and in the cadaster, they are in public ownership and suitable for new uses. The fragments of the corridor of the extinct mill race in Podolínec represent a potential for strengthening the blue and green infrastructure, pedestrian and cycling greenways, and a potential for the presentation of cultural heritage values, which could contribute to the improvement of the qualities of the urban environment.

Abstract Daily oscillations are present in many aspects of the immune system, including responsiveness to infections, allowing temporal alignment of defence mechanisms with the external environment. Our study addresses whether compromised circadian timing function by dim artificial light at night (ALAN) impacts the time dependency of the acute inflammatory response in a rat model of lipopolysaccharide (LPS)-induced inflammation. After 2 weeks of exposure to low-intensity ALAN (~2 lx) or a standard light/dark cycle, male rats were challenged with LPS during either the day or the night. Dim ALAN attenuated the anorectic response when rats were stimulated during their early light phase. Next, ALAN suppressed daily variability in inflammatory changes in blood leukocyte numbers and increased the daytime sensitivity of neutrophils to the priming effects of LPS on oxidative burst. An altered renal inflammatory response in ALAN-exposed rats was manifested by stimulated T-cell infiltration into the kidney upon night-time LPS injection and the modified rhythmic response of genes involved in inflammatory pathways. Moreover, ALAN disturbed steady-state oscillations of the renal molecular clock and eliminated the inflammatory responsiveness of Rev-erbα. Altogether, dim ALAN impaired time-of-day-dependent sensitivity of inflammatory processes, pointing out a causal mechanism between light pollution and negative health effects.

The study's main objective is the possible application of regranulate based on PLA and PHB bioplastics in the FDM 3D printing technique. The idea of using regranulate in the tested PLA/PHB biodegradable polymer blend can help to reduce the amount of plastic waste produced after defective or unwanted 3D printing from these types of materials suitable for 3D printing or after the industrial production of filaments with inadequate geometric parameters, which may help to economize raw material resources and, ultimately, lower the cost of studied polymer materials producing. The regranulate was added to the non-recycled biodegradable polymer blend with the same chemical composition in two different processes for making the filament for 3D printing. Based on testing the processing and utility properties of the processed regranulate materials, it was found that the regranulate partially degrades during multiple processing and thereby reduces the average molar mass and viscosity of the tested material during its processing. However, it was proven that despite the reduction of molecular characteristics after regranulate additions, it was possible to prepare the filaments by both investigated technologies of the regranulate addition and subsequently, it was possible to print such filaments using FDM 3D printing technology, even when the polymer blend contained a high content of regranulate. It was also proven that PLA/PHB materials containing regranulate exhibit comparable thermophysical and strength characteristics to the virgin PLA/PHB polymer blend.

The subject of the presented article is the analysis of the spatial planning legislation that is currently valid and effective and its comparison with the spatial planning legislation that will come into effect on April 1, 2024, in the legal conditions of the Slovak Republic. The authors of the article focused primarily on the comparison of two basic spatial planning tools – spatial planning documents and spatial planning documentation. The issue of the spatial plan of the municipality is elaborated in more detail, while the article points to changes in its legal regulations in connection with the process of land consolidation and the battle against climate change.

Urban overheating, intensified by climate change, poses a critical challenge in Central European cities, witnessing a rise in tropical days. Conventional mechanical cooling systems in buildings significantly contribute to carbon dioxide emissions, exacerbating global warming. In response, windcatchers—traditional Iranian natural cooling systems—emerge as a promising sustainable solution for contemporary architecture, even in non-arid climates. This research aims to evaluate windcatchers’ efficacy in improving building thermal comfort in Central European climates, focusing on Vienna’s urban environment. This study identifies optimal windcatcher designs by analyzing key variables: height variation, inlet dimensions, urban exposure, Building Management System (BMS) temperature thresholds, and integration with an earth tube system using Design Builder simulation software version 6. The findings reveal that a windcatcher standing at 2.5 m tall, with inlet dimensions of 0.9 m by 1.4 m, in an open, less densely populated urban setting, and with open valves when indoor temperatures surpass 22 °C, demonstrates the most effective reduction in cooling load. Moreover, both one-sided and two-sided windcatchers outperform conventional ventilation through openings. Additionally, combining a one-sided windcatcher with an earth tube system ensures efficient cooling even when exterior temperatures exceed 25 degrees Celsius. When augmented by a heat pump, this integrated system can provide heated ventilation.

In recent years, communication using electromagnetic (EM) radiation became an integral part of our lives. As a result, there is a large number of base transceiver stations (BTSs) which act as a source of high EM exposure for inhabitants mainly in the “hot-spot” areas. They employ higher values of radiation, thus, providing potentially harmful effects on living or working environment. The aim of this pilot study was to study a distribution of hot-spots and EMF power in a vicinity of BTSs. BTS was located in an extra-village area at least 500 m away from the nearest city or surrounded villages in the district of Martin. The targeted area of EM radiation from the BTS was divided into two smaller zones, the right and the left. For a better visualization, topographic maps were created. Using spectral analyzer Aaronia Spectran HF-6085, intensities of EMF within the frequency range from 880 – 960 MHz (GSM900) were recorded. Maximum values of EMF power flux density were 146.827 μW/m2 in horizontal and 96.448 μW/m2 in vertical plane. Minimal va lues were 0.052 μW/m2 in horizontal and 0.179 μW/m2 vertical plane respectively. The maps revealed two hotspots in the left zone and also two (smaller and larger) hotspots in the right zone. Our values were below the actual limits given by the Slovak Republic and the International Commission for Non-Ionizing Radiation Protection (ICNIRP) safety guidelines. However, the values from the hotspots were above the limits suggested by the BioInitiative Report. Our results indicate an elevation of EMF values in the hot-spots even in the extra-village areas. Further studies are needed to analyze in detail EMF parameters in the hot-spots, and their effects on living and working environments.

The research aimed to investigate the variability of the acrylamide content in French potato fries depending on the type of oil and the length and conditions of deep-frying. Deep-frozen pre-fried potato French fries primarily intended for catering establishments were deep-fried parallel in two oils (multi-component oil and rapeseed oil) at the same conditions (175 °C/4 min and 200 °C/3 min) until the limit for total polar compounds (TPCs) content (24%) was reached. The samples were analysed immediately after removal from the package, after the first frying and when the TPCs was exceeded. High-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC/ESI-MS/MS) was used to determine acrylamide. Mathematical and statistical evaluation of the results was according to the indicators of descriptive characteristics, i.e., arithmetic mean, standard deviation (SD), and coefficient of variation (%). Analysis of variance (ANOVA) was used to compare groups, i.e., the assumption of agreement of variance was verified by the F test (F). All pairwise differences in means were tested using Tukey's HSD test (Honest Significantly Different) and Scheffe´s test. The critical value of α, compared to the standardized difference between the means, was established using our chosen risk of 5%. The highest acrylamide values were measured in samples deep-fried in rapeseed oil at 200 °C/3 min in sample 2b (451.13 µg/kg when deep-fried immediately) and in sample 2d (383.24 µg/kg after exceeding TPCs). The lowest values of acrylamide were found in samples deep-fried in multi-component oil at a temperature of 200 °C/3 min in sample 1d (183.35 µg/kg after exceeding TPCs) and at a temperature of 175 °C/4 min in sample 1c (240.75 µg/kg after exceeding TPCs). The decreased tendency of acrylamide in both types of oils and variants of temperature after exceeding TPCs compared to the state immediately after frying is confirmed for all samples. Potato-based products are a significant source of acrylamide production and subsequent consumption. Monitoring its presence in food is, therefore, an important legislative requirement.

Sea buckthorn pomace is a by-product of juice production, which is still rich in bioactive compounds. After drying, the pomace can be effectively used as a valuable addition to bakery products supporting their nutritional value. However, due to the high content of the amino acid asparagine in sea buckthorn, this promising material contributes to the undesirable formation of acrylamide. To reduce the risk from this potentially carcinogenic compound, enzymatic treatment of sea buckthorn with asparaginase was applied, which resulted in a substantial reduction of asparagine content from 1834 mg/kg in untreated dried sea buckthorn pomace to 89 mg/kg in enzymatically treated dried sea buckthorn pomace. 10% substitution of wholegrain cereal flour with enzymatically treated sea buckthorn pomace powder in rye and triticale biscuits resulted in a 35% reduction in acrylamide content, in the case of wholegrain wheat biscuits up to a 64% reduction, compared to biscuits with untreated sea buckthorn pomace powder. This study confirmed that treating fruit with asparaginase is an effective way to reduce health risk caused by acrylamide in biscuits enriched with nutritionally valuable fruit pomace.

In this research the meat quality of the two canary sheep local breeds, Canaria breed (CB) and Canaria Hair breed (CHB), was evaluated, making groups of 10 males and females from each, slaughtered at live weights of 9.78 ± 0.49 kg, 15.8 ± 0.66 kg and 24.9 ± 0.76 kg. The breed affected to meat and fat colour at 24 h after slaughter. Meat of CB showed more redness and more chroma values. Fat of CB showed greater lightness. Related to the physio-chemical analysis of the meat, CB showed higher water-holding capacity, shear force and intramuscular fat content that CHB; however, CHB showed higher protein and ash percentages that CB. In relation to fat quality, CB presented higher MUFA percentage and CHB had higher PUFA percentage. CHB showed the lower atherogenic and thrombogenic indexes. Slaughter weight affected the pH, meat and fat colour and also all physio-chemical parameters, except shear force and collagen content and the fatty acid profile. Males had higher moisture content, soluble collagen and PUFA, while females had higher MUFA. The breed effect on meat quality was shown mainly in lambs slaughtered at 10 kg. Owing to their fatty acid profile, the healthiest meat was from lambs slaughtered at 25 kg. [ABSTRACT FROM PUBLISHER]

A crucial aspect concerning the intelligent transport systems is data transmission between vehicle and central control and information systems. Transportation needs a reliable system of data transfer based on GSM or WiFi networks. However, these networks employ a wide range of different frequencies which can be harmful to the health of drivers. The detrimental effect of electromagnetic radiation can negatively affect the process of transportation. This study determines the intensity of electric field levels (E) of the radiofrequency electromagnetic field (RF EMF) during the data transmission through the 3G, 4G and local WiFi networks, comparing them with the limit values. Conclusions: Our results showed a significantly higher level of the E-field intensity during 4G transmission in all places. The limit values were not exceeded. The lowest E-field values were found in local WiFi network.

Introduction: The most common occupational disease is carpal tunnel syndrome. The aim of this study was to translate and validate the Slovakian version of BCTSQ. Methods: The original questionnaire was translated into the Slovakian language by two expert translators. Cronbach’s alpha coefficient was used to analyze the internal consistency of the questionnaire. Construction validity was evaluated by using Pearson’s correlation coefficient and Spearman’s rank correlation. The results were processed in the statistical program SPSS 24. The level of significance p > 0.05 was considered significant. To analyze the validity, a factor analysis of the BCTSQ and the correlation between BCTSQ and SF-36 were obtained. Results: A total of 32 employees at risk of local muscular overload completed the BCTSQ and Health Questionnaire SF-36. Cronbach’s alpha for SSS was >0.8. The alpha coefficient for FSS was >0.9. The Pearson’s coefficient and Spearman’s rank correlation was >0.9 for each domain. Cronbach’s alpha for SF-36 was >0.7 and the Pearson’s coefficient and Spearman’s rank correlation was >0.6 and p-values

(1) Teeth, in humans, represent the most resilient tissues. However, exposure to concentrated acids might lead to their dissolving, thus making human identification difficult. Teeth often contain dental restorations from materials that are even more resilient to acid impact. This paper aims to introduce a novel method for the 3D reconstruction of dental patterns as a crucial step for the digital identification of dental records. (2) With a combination of modern methods, including micro-computed tomography, cone-beam computer tomography, and attenuated total reflection, in conjunction with Fourier transform infrared spectroscopy and artificial intelligence convolutional neural network algorithms, this paper presents a method for 3D-dental-pattern reconstruction, and human remains identification. Our research studies the morphology of teeth, bone, and dental materials (amalgam, composite, glass-ionomer cement) under different periods of exposure to 75% sulfuric acid. (3) Our results reveal a significant volume loss in bone, enamel, dentine, as well as glass-ionomer cement. The results also reveal a significant resistance by the composite and amalgam dental materials to the impact of sulfuric acid, thus serving as strong parts in the dental-pattern mosaic. This paper also probably introduces the first successful artificial intelligence application in automated-forensic-CBCT segmentation. (4) Interdisciplinary cooperation, utilizing the mentioned technologies, can solve the problem of human remains identification with a 3D reconstruction of dental patterns and their 2D projections over existing ante-mortem records.

Allergic rhinitis/rhinosinusitis (AR) is the most common allergic disease. It affects patients’ quality of life and may influence the severity of lower airway disease such as asthma. Therefore, its treatment is of great importance. AR is treated by a combination of effective approaches; however, in some patients, the disease is uncontrolled. In the last several years, the concept of AR has shifted from increased T helper 2 (Th2) cell signaling and downstream inflammation to disease phenotypes with non-Th2-mediated inflammation. AR is a largely heterogenous group of airway diseases, and as such, research should not only focus on immunosuppressive agents (e.g., corticosteroids) but should also include targeted immunomodulatory pathways. Here, we provide an overview of novel therapies, focusing on the role of phosphodiesterase-4 (PDE4) inhibitors in AR. PDE4 inhibitors are potent anti-inflammatory agents that are used for the treatment of inflammatory airway diseases including AR. The PDE4 inhibitor roflumilast was shown to effectively control symptoms of AR in a randomized, placebo-controlled, double-blinded, crossover study in patients with a history of AR. However, only a few PDE4 inhibitors have proceeded to phase II and III clinical trials, due to insufficient clinical efficacy and adverse effects. Research is ongoing to develop more effective compounds with fewer side effects that target specific inflammatory pathways in disease pathogenesis and can provide more consistent benefit to patients with upper airway allergic diseases. Novel specific PDE4 inhibitors seem to fulfill these criteria.

In recent years, there has been an increase in the number of studies on biological effects of Electromagnetic (EM) fields emitted from Base Transceiver Stations (BTSs). The biological effects of generated and real telecommunication signals produced by different types of exposure systems are discussed. However, the proper exposure methods for such experiments are very limited. We successfully developed a simple and cost-effective exposure unit with real GSM/DCS/UMTS signal from BTS containing proper modulations or intermittence (continuous, interrupted). Signal processing and conditioning unit is based on a Radiofrequency (RF) repeater. The downlink signal is filtered by integrated high selectivity passband filters and amplified to a required level. The main part of exposure unit is a Faraday cage with the specimen (exposure) area measuring 150 x 250 mm with E-field percent deviation less than 18%. This exposure system can be helpful in experiments with living organisms in in vivo studies and in vitro studies with normal or pathological cells and other micro scale structures being exposed to RF EM fields from BTS.

Meteorological impacts of El Niño events of 1982–1983 and 1997–1998 were observed in locations throughout the world. In southern Brazil, El Niño events are associated with increased rainfall and higher freshwater discharge mto Patos Lagoon, a large coastal lagoon that empties into the Atlantic Ocean. Based on interdecadal meteorological and biological data sets encompassing the two strongest El Niño events of the last 50 yr, we evaluated the hypothesis that El Niño-induced hydrological changes are a major driving force controlling the interannual variation in the structure and dynamics of fishes in the Patos Lagoon estuary. High rainfall in the drainage basin of the lagoon coincided with low salinity in the estuarine area during both El Niño episodes. Total rainfall in the drainage basin was higher (767 versus 711 mm) and near-zero salinity conditions in the estuarine area lasted about 3 mo longer during the 1997–1998 El Niño event compared with the 1982–1983 event. Hydrological changes triggered by both El Niño events had similar relationships to fish species composition and diversity patterns, but the 1997–1998 event appeared to have stronger effects on the species assemblage. Although shifts in species composition were qualitatively similar during the two El Niño events, distance between El Niño and non-El Niño assemblage multivariate centroids was greater during the 1996–2000 sampling period compared with the 1979–1983 period. We provide a conceptual model of the principal mechanisms and processes connecting the atmospheric-oceanographic interactions triggered by the El Niño phenomena anti their effect on the estuarine fish assemblage. [ABSTRACT FROM AUTHOR]

It is generally acknowledged that there is a correlation between the incidence of ultraviolet burden diseases and overexposure of the body to ultraviolet radiation (UVR). The main goals of our study were to determine the level of knowledge of college students in regard to the effects of UVR, to educate them about it, and finally to urge them to improve their personal protection against the harmful effects of UVR. We performed an educational-questionnaire study of UVR in 2003, 2005, and 2008 years. Responses of 841 students from Jessenius Faculty of Medicine in Martin (JFM), University of Zilina, and St. Elizabeth College of Health and Social Work (SEC) in Bratislava showed a higher level of knowledge in students at JFM and Univ. of Zilina following their education, as compared to those students from SEC. There was little difference in responses to questions related to the protection against UVR. A lower level of knowledge in all groups of students was shown in 2005. Nevertheless, all respondents significantly increased their level of protection against UVR during the years of the study and the number of those visiting solaria decreased. A weak relationship between the knowledge of students and their protection skills against UVR was found, indicating that a complex reason might be involved. This study highlights the importance of providing education that is systematic and longterm to university students in Slovakia (future doctors, bioengineers and nurses). Moreover, this study brings new insights on the surveillance and protection against the harmful effects of UVR to prospective patients.

Iso-dose maps creation and kerma-area products calculation are important procedures in radiotherapy and medical imaging. In this work, a method is presented to obtain iso-dose maps through digital processing of the images obtained from radiochromic films, which are employed to estimate the dose absorbed by the patient. The kerma-area product in selected regions of interest (ROIs) in the iso-dose map was then evaluated. The images were obtained by scanning the irradiated films using a commercial flatbed scanner. The iso-dose areas were extracted by means of an image segmentation algorithm, while calibration for a particular film to obtain a sensitometric curve relating dose to film darkening, was also made. A software interface allowed introducing the scanned image for the estimation of kerma-area products by defining the ROI interactively. The methods developed in this work allowed to implement a software application to obtain the iso-dose maps and kerma-area product in selected ROIs. [ABSTRACT FROM AUTHOR]

Levrier Bay, located in the western part of Mauritanian Cost, has a strategic position in Mauritania’s fish economy and reproduction environment. Recently, fishmeal factories have multiplied in the bay. This study was carried out in Levrier Bay. It is the first one in this area which is interested in assessing the environmental impact of fishmeal factory discharges by measuring several parameters such as suspended matter, chemical oxygen demand (COD), biological oxygen demand (BOD), conductivity, turbidity, and salinity. A total of 27 samples were collected at 9 sites distributed on the link between effluents from factories and the Atlantic Ocean (discharge site). Results show that some parameters are over permissible values, like suspended matter content (SS), which reached 2020 mg. L.-1 level. The turbidity measure shows excessively high values (50 to 961 mg.L.-1); impacted by effluents at the reject point, the seawater conductivity and salinity are particularly low (4.53 to 188.2 and 13 to 56.4, respectively). The total organic carbon (TOC) values ranged from 200 to 780 mg/L, whereas the highest measured level of chemical oxygen demand was 4010 mg.L.-1 Biochemical oxygen demand content ranged from 685 to 961 mg/L. The biodegradability index (COD/BOD) shows that these effluents are not easily biodegradable because the index > 3.

Abstract Background Bovine herpesvirus 5 (BoHV-5) is a member of the subfamily Alphaherpesvirinae responsible for meningo-encephalitis in young cattle. The first case of bovine meningo-encephalitis associated with a herpesvirus infection was reported in Australia. The current geographical distribution of BoHV-5 infection is mainly restricted to South America, especially Brazil and Argentina. Outbreaks of BoHV-5 are regularly observed in Argentina suggesting the circulation of the virus in the bovine population. Results Seventeen field strains of BoHV-5 isolated from 1984 to now were confirmed by differential PCR and subjected to restriction endonuclease analysis (REA). Viral DNA was cleaved with BstEII which allows the differentiation among subtypes a, b and non a, non b. According to the REA with BstEII, only one field strain showed a pattern similar to the Argentinean A663 strain (prototype of BoHV-5b). All other isolates showed a clear pattern similar to the Australian N569 strain (prototype of BoHV-5a) consistent with the subtypes observed in Brazil, the other South-American country where BoHV-5 is known to be prevalent. The genomic region of subtype b responsible for the distinct pattern was determined and amplified by PCR; specifically a point mutation was identified in glycoprotein B gene, on the BstEII restriction site, which generates the profile specific of BoHV-5b. Conclusions This is the first report of circulation of BoHV-5a in Argentina as the prevailing subtype. Therefore the circulation of BoHV-5b was restricted to a few years in Argentina, speculating that this subtype was not able to be maintained in the bovine population. The mutation in the gB gene is associated with the difference in the restriction patterns between subtypes "a" and "b".

Hyperreactive platelets are commonly observed in diabetic patients indicating a potential link between glucose homeostasis and platelet reactivity. This raises the possibility that platelets may play a role in the regulation of metabolism. Pancreatic β cells are the central regulators of systemic glucose homeostasis. Here, we show that factor(s) derived from β cells stimulate platelet activity and platelets selectively localize to the vascular endothelium of pancreatic islets. Both depletion of platelets and ablation of major platelet adhesion or activation pathways consistently resulted in impaired glucose tolerance and decreased circulating insulin levels. Furthermore, we found platelet-derived lipid classes to promote insulin secretion and identified 20-Hydroxyeicosatetraenoic acid (20-HETE) as the main factor promoting β cells function. Finally, we demonstrate that the levels of platelet-derived 20-HETE decline with age and that this parallels with reduced impact of platelets on β cell function. Our findings identify an unexpected function of platelets in the regulation of insulin secretion and glucose metabolism, which promotes metabolic fitness in young individuals., (© 2023 The Authors. Published under the terms of the CC BY 4.0 license.)

The regular overconsumption of energy-dense foods (rich in lipids and sugars) results in elevated intestinal nutrient absorption and consequently excessive accumulation of lipids in the liver, adipose tissue, skeletal muscles, and other organs. This can eventually lead to obesity and obesity-associated diseases such as type 2 diabetes (T2D), non-alcoholic fatty liver disease (NAFLD), cardiovascular disease, and certain types of cancer, as well as aggravate inflammatory bowel disease (IBD). Therefore, targeting the pathways that regulate intestinal nutrient absorption holds significant therapeutic potential. In this review, we discuss the molecular and cellular mechanisms controlling intestinal lipid handling, their relevance to the development of metabolic diseases, and emerging therapeutic strategies., (© 2022 The Authors. Published under the terms of the CC BY 4.0 license.)

Members of the protein kinase D (PKD) family (PKD1, 2, and 3) integrate hormonal and nutritional inputs to regulate complex cellular metabolism. Despite the fact that a number of functions have been annotated to particular PKDs, their molecular targets are relatively poorly explored. PKD3 promotes insulin sensitivity and suppresses lipogenesis in the liver of animals fed a high-fat diet. However, its substrates are largely unknown. Here we applied proteomic approaches to determine PKD3 targets. We identified more than 300 putative targets of PKD3. Furthermore, biochemical analysis revealed that PKD3 regulates cAMP-dependent PKA activity, a master regulator of the hepatic response to glucagon and fasting. PKA regulates glucose, lipid, and amino acid metabolism in the liver, by targeting key enzymes in the respective processes. Among them the PKA targets phenylalanine hydroxylase (PAH) catalyzes the conversion of phenylalanine to tyrosine. Consistently, we showed that PKD3 is activated by glucagon and promotes glucose and tyrosine levels in hepatocytes. Therefore, our data indicate that PKD3 might play a role in the hepatic response to glucagon., (© 2021 Loza-Valdes et al.)

Lipids are the most energy-dense components of the diet, and their overconsumption promotes obesity and diabetes. Dietary fat content has been linked to the lipid processing activity by the intestine and its overall capacity to absorb triglycerides (TG). However, the signaling cascades driving intestinal lipid absorption in response to elevated dietary fat are largely unknown. Here, we describe an unexpected role of the protein kinase D2 (PKD2) in lipid homeostasis. We demonstrate that PKD2 activity promotes chylomicron-mediated TG transfer in enterocytes. PKD2 increases chylomicron size to enhance the TG secretion on the basolateral side of the mouse and human enterocytes, which is associated with decreased abundance of APOA4. PKD2 activation in intestine also correlates positively with circulating TG in obese human patients. Importantly, deletion, inactivation, or inhibition of PKD2 ameliorates high-fat diet-induced obesity and diabetes and improves gut microbiota profile in mice. Taken together, our findings suggest that PKD2 represents a key signaling node promoting dietary fat absorption and may serve as an attractive target for the treatment of obesity., (© 2021 The Authors. Published under the terms of the CC BY 4.0 license.)

Nutrient overload in combination with decreased energy dissipation promotes obesity and diabetes. Obesity results in a hormonal imbalance, which among others activates G protein-coupled receptors utilizing diacylglycerol (DAG) as secondary messenger. Protein kinase D1 (PKD1) is a DAG effector, which integrates multiple nutritional and hormonal inputs, but its physiological role in adipocytes is unknown. Here, we show that PKD1 promotes lipogenesis and suppresses mitochondrial fragmentation, biogenesis, respiration, and energy dissipation in an AMP-activated protein kinase (AMPK)-dependent manner. Moreover, mice lacking PKD1 in adipocytes are resistant to diet-induced obesity due to elevated energy expenditure. Beiging of adipocytes promotes energy expenditure and counteracts obesity. Consistently, deletion of PKD1 promotes expression of the β3-adrenergic receptor (ADRB3) in a CCAAT/enhancer binding protein (C/EBP)-α- and δ-dependent manner, which leads to the elevated expression of beige markers in adipocytes and subcutaneous adipose tissue. Finally, deletion of PKD1 in adipocytes improves insulin sensitivity and ameliorates liver steatosis. Thus, depletion of PKD1 in adipocytes increases energy dissipation by several complementary mechanisms and might represent an attractive strategy to treat obesity and its related complications., (© 2018 The Authors.)