Histidine Promotes the Glucose Synthesis through Activation of the Gluconeogenic Pathway in Bovine Hepatocytes

Histidine (His) is considered to be the first-limiting amino acid (AA) on grass silage-based diets in lactation cows, which correlate positively with lactose yield. The higher glucose requirements of lactating cows can be met through a combination of increased capacity for gluconeogenesis and increased supply of gluconeogenic precursors. However, the effect of His on the expression of gluconeogenic genes in the bovine hepatocytes is less known. Therefore, this study aimed to investigate the regulatory effect of His on the key gluconeogenic genes and glucose output in bovine hepatocytes. The addition of 0.15, 0.6, and 1.2 mM His in a medium significantly enhanced (p < 0.05) the viability of bovine hepatocytes. Remarkably, 1.2 mM His induced profound changes (p < 0.05) in the mRNA level of key genes involved in gluconeogenesis, including PCK1, PCK2, FBP1, and G6PC in vitro. Furthermore, the mRNA expression of PCK1 was significantly elevated (p < 0.05) by the addition of 1.2 mM His at 3, 6, 12, and 24 h of incubation. The hepatic glucose output increased (p < 0.05) linearly with increasing His concentration. These findings indicate that the addition of His may be efficiently converted into glucose via the upregulation of genes related to the gluconeogenic pathway.

MYCN mediates cysteine addiction and sensitizes to ferroptosis

Aberrant expression of MYC family members predicts poor clinical outcome in many human cancers. Oncogenic MYC profoundly alters metabolism and mediates an antioxidant response to maintain redox balance. Here we show that MYC induces massive lipid peroxidation upon depletion of cysteine, the rate-limiting amino acid for glutathione biosynthesis and sensitizes cells to ferroptosis, an oxidative, non-apoptotic and iron-dependent type of cell death. In MYCN-amplified childhood neuroblastoma, MYCN mediates resistance to ferroptosis by activating transsulfuration of methionine to cysteine. MYCN may contribute to spontaneous tumor regression in low-risk neuroblastomas by promoting ferroptosis in cells with epigenetically silenced cystathionine-beta-synthase, the rate-limiting enzyme for transsulfuration. We identified enzymes and antiporter proteins crucial to ferroptotic escape, providing multiple previously unknown sites that may be acted on therapeutically.

Nutritional and Functional Properties of Gluten-Free Flours

This study characterized and compared 13 gluten-free (GF) flours (rice, brown rice, maize, oat, millet, teff, amaranth, buckwheat, quinoa, chickpea, gram, tiger nut, and plantain) for their nutritional and functional properties. For all GF flours investigated, starch was the major component, except for gram, chickpea, and tiger nut flours with lower starch content (<45%), but higher fiber content (8.8–35.4%). The higher amount of calcium, magnesium, zinc, potassium, phosphorus, similar values for iron and lower content of sodium in gram, makes this flour a good alternative to chickpea or other GF flour to develop healthier food products. Amaranth flour had a high protein digestibility, while tiger nut and millet flours were less digestible. Gram, chickpea, quinoa, buckwheat, and oat flours fulfilled amino acids recommendation for daily adult intake showing no limiting amino acid. Total polyphenolic content and antioxidant capacity showed higher values for buckwheat, followed by quinoa and maize flours. Gram, chickpea, maize, and quinoa flours are good candidates to improve health conditions due to lower saturated fatty acid content. The findings of this study provide useful insights into GF flours and may contribute to the development of novel gluten-free products like bread, cookies, or pasta.

Effect of Feeding Bio-fortified Maize on Performance and Slaughter Parameters in Vanaraja Birds

Background: The normal maize contains high zein fraction and devoid of lysine and tryptophan thus making lysine as second limiting amino acid in it. The opaque-2 and floury-2 mutants produce higher levels of lysine and tryptophan. Through plant breeding programme, bio-fortified maize (Provitamin-A enriched) is being produced. Therefore, the study was conducted to determine the effect feeding different bio-fortified maize based diets in Vanaraja birds.Methods: The experiment was conducted during January to April 2018 at ICAR-Directorate of Poultry Research. For the purpose, 175 day old chicks were randomly divided into 5 dietary groups each having 7 replicates with 5 birds each. Five experimental diets were formulated to contain normal maize (Diet 1), Vivek Hybrid 9 (Diet 2), APQH9 (Diet 3), Vivek QPM 9 (Diet 4) and white maize (Diet 5). The experimental diets fed ad libitum to all the chicks up to 6 weeks (nursery phase) and recorded performance parameters.Result: Improved feed efficiency was recorded in the group fed diet with APQH9 (Diet 3) compared to other experimental diets. The decrease in abdominal fat and increased breast muscle among the birds fed diet contained Vivek QPM 9 (Diet 4) and APQH9 (Diet 3) was recorded in comparison to other dietary groups. Hence, it is concluded that the birds fed QPM and QPM + Provit A showed an improved feed efficiency, reduced abdominal fat and increased breast muscle in Vanaraja birds during nursery phase.

PKCα Inhibition as a Strategy to Sensitize Neuroblastoma Stem Cells to Etoposide by Stimulating Ferroptosis

Cancer stem cells (CSCs) are a limited cell population inside a tumor bulk characterized by high levels of glutathione (GSH), the most important antioxidant thiol of which cysteine is the limiting amino acid for GSH biosynthesis. In fact, CSCs over-express xCT, a cystine transporter stabilized on cell membrane through interaction with CD44, a stemness marker whose expression is modulated by protein kinase Cα (PKCα). Since many chemotherapeutic drugs, such as Etoposide, exert their cytotoxic action by increasing reactive oxygen species (ROS) production, the presence of high antioxidant defenses confers to CSCs a crucial role in chemoresistance. In this study, Etoposide-sensitive and -resistant neuroblastoma CSCs were chronically treated with Etoposide, given alone or in combination with Sulfasalazine (SSZ) or with an inhibitor of PKCα (C2-4), which target xCT directly or indirectly, respectively. Both combined approaches are able to sensitize CSCs to Etoposide by decreasing intracellular GSH levels, inducing a metabolic switch from OXPHOS to aerobic glycolysis, down-regulating glutathione-peroxidase-4 activity and stimulating lipid peroxidation, thus leading to ferroptosis. Our results suggest, for the first time, that PKCα inhibition inducing ferroptosis might be a useful strategy with which to fight CSC chemoresistance.

Sustainable and regional gastronomy: cassava leaves as a potential ingredient for gluten-free biscuits

The addition of roots derivatives to bakery products may be a promising alternative to add value to these products. This study aimed to characterize and evaluate the effect of cassava leaves on the properties of gluten-free biscuits (GFB). The ingredients used were cassava flour, rice flour, cuí, tapioca flour, and 0 (F0), 3.69% (F1), 5.34% (F2), and 7.38% (F3) of cassava leaves (CCL). The results were evaluated by analysis of variance, followed by Scott-Knott test (p-value<0.05). The CCL presented 89.9% moisture, water activity of 0.98, and 2.75% protein; tryptophan was the limiting amino acid. No significant differences were observed between the F0-control and those made with the addition of CCL, which presented moisture and Aw below 3% and 0.30, and hardness between 45 to 60 N. The sensory acceptance scores were greater than 6, which indicates that it is possible to increase the added value of CCL in bakery products. The use of cassava leaves in biscuits showed good technological and sensory characteristics, making it possible to be an ingredient from regional by-products that can favor sustainable development, respect the concept of regionalization, and add income and employment.

Use of the precision-fed cecectomized rooster assay to determine standardized amino acid digestibility, true metabolizable energy content, and digestible indispensable amino acid scores of plant-based protein by-products used in canine and feline diets

Traditionally, protein by-products from oil seeds and cereal grains have been used in pet foods as sustainable, inexpensive, and protein-rich ingredients. However, the on-going demonization of soy- and corn-based ingredients continue to hinder their use in pet food and treat formulations. Ideally, the further demonstration of their protein quality and nutrient composition may encourage their favorable return as acceptable ingredients in pet foods and treats. Therefore, the objectives of this study were to determine the macronutrient composition, indispensable amino acid profile, standardized amino acid digestibility, true metabolizable energy content corrected for nitrogen (TMEn), and digestible indispensable amino acid scores (DIAAS-like) of soy flakes (SF), peanut flour (PF), soybean meal (SBM), and corn gluten meal (CGM). Standardized amino acid digestibility was assessed using the precision-fed cecectomized rooster assay. All test ingredients demonstrated a profile of highly digestible indispensable amino acids except for lysine in PF, which was lowest (P &lt; 0.05) at 45.5%. The SBM and CGM had the highest (P &gt; 0.05) digestibilities of indispensable amino acids. A DIAAS-like values was calculated for each ingredient using either AAFCO (2020) recommended values or NRC (2006) recommended allowances as the reference protein pattern. For adult dogs compared to AAFCO recommended values, the first-limiting amino acid was lysine for PF and CGM but it was methionine for SF and SBM. For adult cats compared to AAFCO recommended values, the first-limiting amino acid was lysine for PF and CGM but it was threonine for SF. There was no first-limiting amino acid in SBM for cats as DIAAS-like values were over 100% for all indispensable amino acids. The TMEn values were highest (P &lt; 0.05) for PF and CGM (4.58 and 4.31 kcal/g [dry matter basis], respectively). The protein quality of these plant-based protein by-products reflect their value as nutritional ingredients for canine and feline diets. However, the prior processing of these by-products must be considered before exposing them to additional processing methods, such as extrusion. Additionally, the inclusion of complementary proteins or supplemental amino acids will be needed to meet all indispensable amino acid requirements for a nutritionally complete and balanced pet food.

Effect of harvest season on the nutritional value of bee pollen protein

Bee pollen is a natural product that has valuable nutritional and medicinal characteristics and has recently garnered increasing attention in the food industry due to its nutritive value. Here, we harvested pollen loads from the Al-Ahsa oasis in eastern Saudi Arabia during spring, summer, autumn, and winter in 2018/2019 to compare the nutritional value of bee pollen protein with the amino acid requirements of honeybees and adult humans. Based on the nutritional value of bee pollen protein, the optimal season for harvesting bee pollen was determined. The composition of the bee pollen showed the highest contents of crude protein, total amino acids, leucine, glutamic acid, valine, isoleucine, threonine, and glycine in samples collected in spring. The highest contents of lysine, phenylalanine, threonine, tryptophan, arginine, tyrosine, and cysteine were observed in samples collected in winter. The highest contents of histidine, methionine, and serine were in samples collected in autumn. Moreover, the highest levels of aspartic acid, proline, and alanine were in samples collected in summer. Leucine, valine, lysine, histidine, threonine, and phenylalanine (except in autumn bee pollen) contents in pollen from all four seasons were above the requirements of honeybees. Leucine, valine, histidine, isoleucine (except in autumn bee pollen), lysine (except in spring and summer bee pollen), and threonine (except in winter and spring bee pollen) in all tested samples were above the requirements of adult humans. In comparison with the minimal amino acid requirements of adult humans and honeybees, the 1st limiting amino acid in bee pollen collected during the different seasons was methionine. Bee pollen collected during spring (March–May) and winter (December–February) can be considered a nutritive food source for adult humans and honeybees.

Profil Asam Amino Ekstrak Mukus Ikan Glodok (Boleophthalmus boddarti) dari Kawasan Mangrove Cilacap, Jawa Tengah

Mudskipper or glodok fish is a unique fish that can crawl and climb mangrove roots with their fins. In Indonesia, this fish is exported to abroad as a source of food. The by-product of this fish is rarely used, which one is their mucus. Protein is a composition of fish mucus which consists of amino acids. The mucus of fish has the potential as a source of medicine because it’s proven to have antibacterial, antiviral, and antifungal activities. This study aims to determine the protein and amino acid content of fresh meat and mucus extract of mudskipper. Protein content testing was carried out using the titrimetric method, while amino acid content using the UPLC method. In this study, mucus extract has protein content at 1.79%. It’s small than the protein content of fresh meat at 17.7%. The highest essential amino acid in fresh meat and mucus extract of mudskipper was leucine (15% and 0.91%). The highest nonessential amino acid in fresh meat and mucus extract of mudskipper were glutamic acid (26.4% and 1.6%). The limiting amino acid in fresh meat is leucine as 226.9% and lysine as 12.27% in the mucus extract of mudskipper.

Amino Acid Composition of Kilishi - Nigerian (Beef Jerky) Meat

The article reports the amino acid composition of Nigerian beef jerky meat called Kilishi. Kilishi is consumed dry, hence determination was on dry weight basis. Sample was purchased in Ado-Ekiti, Nigeria. Amino acid values were highest for non-essential amino acid in Glu (14.3 g100g-1) whereas from essential amino acid it was Lys (8.69 g100g-1). Other high value amino acids were (in g100g-1): Asp (8.85), Leu (7.68), Arg (6.02), Ile (4.08), Trp (1.02), Cys (1.18) and His (2.40). P-PER1,2,3 values were superior at values of 2.52 – 2.70. EAAI1 (soybean standard) was 1.23 and EAAI2 (egg standard) was 94.5 with corresponding BV of 91.3. Lys/Trp was very high at 8.55 and Met/Trp was 2.38. Values of TNEAA was 52.1 g100g-1 (57.7%) and TEAA was 38.2 g100g-1(42.3%). In the egg score comparison Ser (0.461) was the limiting amino acid (LAA) with protein corrected digestibility value of 0.338; in provisional EAA scoring pattern, LAA was Val (0.882) and corrected version was 0.742; in pre-school children requirement, LAA was Trp (0.927) and corrected value of 0.780. Variation percentage values between the scores/corrected scores were virtually 12.2% per parameter compared. Correlation values between each score standard/corrected score values were significantly different at r=0.01 with values of 0.9997 – 0.99999. Estimates of amino acid requirements at ages 10 – 12 years (mg kg-1 day-1) showed kilishi to be better than the standards at 74.9% - 453%. Results showed that kiishi is protein-condensed.