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1.
Front Pharmacol ; 15: 1377876, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38567357

RESUMEN

Introduction: Acori Tatarinowii Rhizoma (ATR) is a well-known traditional Chinese medicine that is used for treating neuropathic diseases. However, there is little information about the safety of ATR. Methods: The present study evaluated the acute and subacute oral toxicity of a water extract of ATR in Institute of Cancer Research (ICR) mice. In acute trials, a single administration of extract at a dose 5,000 mg/kg body weight led to no clinical signs of toxicity or mortality, indicating that the lethal dose (LD50) exceeded 5,000 mg/kg. A subacute toxicity test was done using daily doses of 1,250, 2,500, and 5,000 mg/kg of the ATR extract for 28 days, which did not show any adverse clinical symptoms or mortality. However, the male renal organ index and urea level in mice given 5,000 mg/kg was obviously abnormal, which was consistent with pathological results and suggested that this dose might cause kidney injury. Results: Doses of ATR lower than 2,500 mg/kg could be regarded as safe, although the potential cumulative effects of long-term use of high doses of ATR need to be considered. Discussion: The study highlights the function of ATR in reducing blood lipids and provides a new idea for its widespread clinical use in the future.

2.
Elife ; 122024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38650461

RESUMEN

Transporter research primarily relies on the canonical substrates of well-established transporters. This approach has limitations when studying transporters for the low-abundant micromolecules, such as micronutrients, and may not reveal physiological functions of the transporters. While d-serine, a trace enantiomer of serine in the circulation, was discovered as an emerging biomarker of kidney function, its transport mechanisms in the periphery remain unknown. Here, using a multi-hierarchical approach from body fluids to molecules, combining multi-omics, cell-free synthetic biochemistry, and ex vivo transport analyses, we have identified two types of renal d-serine transport systems. We revealed that the small amino acid transporter ASCT2 serves as a d-serine transporter previously uncharacterized in the kidney and discovered d-serine as a non-canonical substrate of the sodium-coupled monocarboxylate transporters (SMCTs). These two systems are physiologically complementary, but ASCT2 dominates the role in the pathological condition. Our findings not only shed light on renal d-serine transport, but also clarify the importance of non-canonical substrate transport. This study provides a framework for investigating multiple transport systems of various trace micromolecules under physiological conditions and in multifactorial diseases.


Asunto(s)
Sistema de Transporte de Aminoácidos ASC , Transportadores de Ácidos Monocarboxílicos , Serina , Serina/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Sistema de Transporte de Aminoácidos ASC/metabolismo , Animales , Humanos , Riñón/metabolismo , Ratones , Sodio/metabolismo , Transporte Biológico , Masculino
3.
World J Clin Cases ; 12(5): 1033-1035, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38414610

RESUMEN

This letter praises a recent article in the World Journal of Clinical Cases (Roles of biochemistry data, lifestyle, and inflammation in identifying abnormal renal function in old Chinese), examining factors affecting abnormal renal function in elderly Chinese using advanced machine learning. It highlights the importance of uric acid, age, hemoglobin, body mass index, sport hours, and systolic blood pressure. The study's holistic approach, integrating lifestyle and inflammation, offers a nuanced understanding of chronic kidney disease risk factors. The letter suggests exploring mechanistic pathways of hyperuricemia, the link between anemia and renal function, and the connection between body mass index and estimated glomerular filtration rate. It advocates investigating physical activity's impact on renal health and the independent effects of blood pressure. The study significantly contributes to chronic kidney disease understanding, proposing avenues for further exploration and interventions. Commendations are extended to the authors and the journal.

4.
Heliyon ; 10(3): e24780, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38318056

RESUMEN

Nutritional supplements have been used to improve immune function. Condensed fuzheng extract (CFE) is a well-known traditional Chinese medicine (TCM) formula that is predominantly made from sheep placenta, Astragalus mongholicus Bunge, and Polygonatum kingianum Collett & Hemsl. However, the toxicological profile of CFE has not been determined. In this study, we investigated the acute (14 days) and sub-chronic (90 days) oral toxicities of CFE in mice and rats and the phytochemical composition of CFE. Materials and methods: For the assessment of acute toxicity, 80 ICR mice of both sexes were randomly divided into four groups. Three groups were treated with 4500, 2250 and 1125 mg/kg/d bw CFE daily (n = 10/group per sex) for 14 days; a separate group was used as control. To test the sub-chronic toxicity, male and female Sprague Dawley rats were orally administered 8150, 4075 or 2037 mg/kg bw of CFE for 90 days; a control group was included. Hematological, biochemical, and histopathological markers were tested at the end of the experiment. The chemical composition of CFE was determined by UPLC-HRMS method. Results: In both acute and sub-chronic toxicity studies, no mortalities, indications of abnormality, or treatment-related adverse effects were observed. The LD50 of CFE was higher than 4500 mg/kg. There were no significant changes in the hematological and biochemical data in the treatment group compared with the control group (p > 0.05). Histopathological analyses of the heart, liver, spleen, lungs, kidneys, thymus, testes (male rats) and ovaries (female rats) revealed no anatomical changes of each organ. Phytochemical analysis of CFE revealed the presence of flavonoids (highest abundance), phenols and alkaloids. In conclusion, our results showed that CFE is a safe and non-toxic formula. We also reported phytochemicals in CFE that may possess important pharmacological effects.

5.
Poult Sci ; 103(3): 103382, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38176373

RESUMEN

Deficiencies or excesses of dietary amino acids, and especially of methionine (Met), in laying hens can lead to abnormal protein anabolism and oxidative stress, which affect methylation and cause cellular dysfunction. This study investigated the effects of dietary methionine (Met) levels on growth performance, metabolism, immune response, antioxidant capacity, and the subsequent development of laying hens. A total of 384 healthy 1-day-old Hyline Grey chicks of similar body weight were randomly allocated to be fed diets containing 0.31%, 0.38%, 0.43% (control group), or 0.54% Met for 6 wk, with 6 replicates of 16 chicks in each. The growth performance of the chicks was then followed until 20 wk old. The results showed dietary supplementation with 0.43% or 0.54% Met significantly increased their mean daily body weight gain, final weight, and Met intake. However, the feed:gain (F/G) decreased linearly with increasing Met supplementation, from 0.31 to 0.54% Met. Met supplementation increased the serum albumin, IgM, and total glutathione concentrations of 14-day-old chicks. In contrast, the serum alkaline phosphatase activity and hydroxyl radical concentration tended to decrease with increasing Met supplementation. In addition, the highest serum concentrations of IL-10, T-SOD, and GSH-PX were in the 0.54% Met-fed group. At 42 d of age, the serum ALB, IL-10, T-SOD, GSH-PX, T-AOC, and T-GSH were correlated with dietary Met levels. Finally, Met supplementation reduced the serum concentrations of ALP, IL-1ß, IgA, IgG, hydrogen peroxide, and hydroxyl radicals. Thus, the inclusion of 0.43% or 0.54% Met in the diet helps chicks achieve superior performance during the brooding period and subsequently. In conclusion, Met doses of 0.43 to 0.54% could enhance the growth performance, protein utilization efficiency, antioxidant capacity, and immune responses of layer chicks, and to promote more desirable subsequent development during the brooding period.


Asunto(s)
Antioxidantes , Metionina , Animales , Femenino , Metionina/farmacología , Interleucina-10 , Pollos , Racemetionina , Glutatión , Radical Hidroxilo , Inmunidad , Suplementos Dietéticos , Peso Corporal , Superóxido Dismutasa
6.
Elife ; 122024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38252473

RESUMEN

Fibroblast growth factor 2 (FGF2) exits cells by direct translocation across the plasma membrane, a type I pathway of unconventional protein secretion. This process is initiated by phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2)-dependent formation of highly dynamic FGF2 oligomers at the inner plasma membrane leaflet, inducing the formation of lipidic membrane pores. Cell surface heparan sulfate chains linked to glypican-1 (GPC1) capture FGF2 at the outer plasma membrane leaflet, completing FGF2 membrane translocation into the extracellular space. While the basic steps of this pathway are well understood, the molecular mechanism by which FGF2 oligomerizes on membrane surfaces remains unclear. In the current study, we demonstrate the initial step of this process to depend on C95-C95 disulfide-bridge-mediated FGF2 dimerization on membrane surfaces, producing the building blocks for higher FGF2 oligomers that drive the formation of membrane pores. We find FGF2 with a C95A substitution to be defective in oligomerization, pore formation, and membrane translocation. Consistently, we demonstrate a C95A variant of FGF2 to be characterized by a severe secretion phenotype. By contrast, while also important for efficient FGF2 secretion from cells, a second cysteine residue on the molecular surface of FGF2 (C77) is not involved in FGF2 oligomerization. Rather, we find C77 to be part of the interaction interface through which FGF2 binds to the α1 subunit of the Na,K-ATPase, the landing platform for FGF2 at the inner plasma membrane leaflet. Using cross-linking mass spectrometry, atomistic molecular dynamics simulations combined with a machine learning analysis and cryo-electron tomography, we propose a mechanism by which disulfide-bridged FGF2 dimers bind with high avidity to PI(4,5)P2 on membrane surfaces. We further propose a tight coupling between FGF2 secretion and the formation of ternary signaling complexes on cell surfaces, hypothesizing that C95-C95-bridged FGF2 dimers are functioning as the molecular units triggering autocrine and paracrine FGF2 signaling.


Asunto(s)
Espacio Extracelular , Factor 2 de Crecimiento de Fibroblastos , Dimerización , ATPasa Intercambiadora de Sodio-Potasio , Disulfuros
7.
J Appl Toxicol ; 44(2): 201-215, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37697829

RESUMEN

Huobahua, namely, Tripterygium hypoglaucum (Levl.) Hutch, known as a traditional Chinese herbal medicine, especially its underground parts, has been widely developed into several Tripterygium agents for the treatment of rheumatoid arthritis and other autoimmune diseases. It has sparked wide public concern about its safety, such as multi-organ toxicity. However, the toxic characteristics and damage mechanism of Huobahuagen extract (HBHGE) remain unclear. In the present study, subchronic oral toxicity study of HBHGE (10.0 g crude drug/kg/day for 12 weeks) was performed in male rats. Hematological, serum biochemical, and histopathological parameters, urinalysis, and plasma metabolic profiling were assessed. The single-dose subchronic toxicity results related to HBHGE exhibited obvious toxicity to the testis and epididymis of male rats. Furthermore, plasma metabolomics analysis suggested that a series of metabolic disorders were induced by oral administration of HBHGE, mainly focusing on amino acid (glutamate, phenylalanine, and tryptophan) metabolisms, pyrimidine metabolism, glutathione metabolism, and steroid hormone biosynthesis. Moreover, it appeared that serum testosterone in male rats treated with HBHGE for 12 weeks, decreased significantly, and was susceptible to the toxic effects of HBHGE. Taken together, conventional pathology and plasma metabolomics for preliminarily exploring subchronic toxicity and underlying mechanism can provide useful information about the reduction of toxic risks from HBHGE and new insights into the development of detoxification preparations.


Asunto(s)
Medicina Tradicional China , Testículo , Ratas , Masculino , Animales , Metabolómica/métodos , Plasma , Tripterygium/química , Extractos Vegetales/toxicidad , Pruebas de Toxicidad Subcrónica
8.
J Anim Physiol Anim Nutr (Berl) ; 108(1): 243-251, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37746672

RESUMEN

Recently, it is necessary to formulate high-quality, balanced and low-cost rations for ruminants from nontraditional sources. The present study conducted to investigate the impact of partially replacing corticated cottonseed (CS) cake with sesame meal (SM) in a lamb feedlot diet on growth performance, nutrient digestion, rumen fermentation and blood biochemistry. Fifteen growing lambs with an initial body weight of 27.4 ± 1.2 kg (6-7 months old) were randomly assigned into three equal groups (n = 5). Lambs in control group (CS) fed a basal diet, while 8% and 16% SM were used to replace an equal portion of corticated CS cake in the second (8SM) and third (16SM) groups respectively. Results showed that most parameters of growth performance and nutrient digestibility were significantly improved (p < 0.05) with the partial replacement of SM (8SM and/or 16SM). Regarding ruminal parameters, ruminal pH and total volatile fatty acids concentration increased (p < 0.05), while ammonia level and total protozoa count decreased with the partial replacement of SM. Moreover, blood parameters showed variant responses to SM partial replacement. Total protein increased, and glucose decreased significantly with 16SM, while cholesterol showed a significant decreasing with both SM replacement levels. SM may substitute CS cake in lamb diet without detrimental effects on performance, digestibility and ruminal fermentation.


Asunto(s)
Aceite de Semillas de Algodón , Sesamum , Ovinos , Animales , Aceite de Semillas de Algodón/metabolismo , Alimentación Animal/análisis , Fermentación , Rumen/metabolismo , Digestión , Dieta/veterinaria , Nutrientes
9.
J Exp Bot ; 75(6): 1654-1670, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-37889862

RESUMEN

Mass spectrometry imaging (MSI) has emerged as an invaluable analytical technique for investigating the spatial distribution of molecules within biological systems. In the realm of plant science, MSI is increasingly employed to explore metabolic processes across a wide array of plant tissues, including those in leaves, fruits, stems, roots, and seeds, spanning various plant systems such as model species, staple and energy crops, and medicinal plants. By generating spatial maps of metabolites, MSI has elucidated the distribution patterns of diverse metabolites and phytochemicals, encompassing lipids, carbohydrates, amino acids, organic acids, phenolics, terpenes, alkaloids, vitamins, pigments, and others, thereby providing insights into their metabolic pathways and functional roles. In this review, we present recent MSI studies that demonstrate the advances made in visualizing the plant spatial metabolome. Moreover, we emphasize the technical progress that enhances the identification and interpretation of spatial metabolite maps. Within a mere decade since the inception of plant MSI studies, this robust technology is poised to continue as a vital tool for tackling complex challenges in plant metabolism.


Asunto(s)
Metaboloma , Plantas , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Plantas/metabolismo , Raíces de Plantas/metabolismo , Semillas
10.
J Sci Food Agric ; 104(5): 3069-3079, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38072654

RESUMEN

BACKGROUND: ε-polylysine hydrochloride (ε-PLH) is a naturally occurring antimicrobial peptide extensively utilized in the food and medical industries. However, its impact on animal husbandry remains to be further explored. Therefore, the present study aimed to determine the effect of ε-PLH on laying hens' health and laying performance. RESULTS: Dietary supplementation with ε-PLH to the diet significantly increased average egg weight during weeks 1-8. Meanwhile, compared with the control group, supplementation with ε-PLH decreased the feed egg ratio during weeks 9-12 and egg breakage rate during weeks 9-16 ,whereas it increased eggshell strength during weeks 1-4 and 13-16 . The ε-PLH 0.05% group increased yolk percentage during weeks 5-8 and yolk color during weeks 1-4 . Furthermore, ε-PLH supplementation significantly increased the concentrations of total protein, albumin, globulin and reproductive hormones estradiol, as well as decreased interleukin-1 beta and malondialdehyde in the serum. Compared with the control group, supplementation with 0.05% ε-PLH significantly increased the relative abundance of Cyanobacteria and Gastranaerophilales and decreased the abundance of Desulfovibrio and Streptococcus in the cecum microbiota. In addition, ε-PLH 0.1% supplementation also increased acetic acid content in the cecum. CONCLUSION: Dietary supplementation with ε-PLH has a positive impact on both productive performance and egg quality in laying hens. Furthermore, ε-PLH can also relieve inflammation by promoting the immunity and reducing oxidative damage during egg production. ε-PLH has been shown to improve intestinal morphology, gut microbial diversity and intestinal health. © 2023 Society of Chemical Industry.


Asunto(s)
Microbioma Gastrointestinal , Animales , Femenino , Polilisina/farmacología , Pollos/microbiología , Suplementos Dietéticos/análisis , Dieta/veterinaria , Ácidos Grasos Volátiles , Alimentación Animal/análisis
11.
J Ethnopharmacol ; 319(Pt 3): 117284, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-37844741

RESUMEN

ETHNOPHARMACOLOGY RELEVANCE: Sanghuangporus vaninii (S. vaninii), as a traditional large medicinal fungus, has a history of more than 2000 years in Chinese history and has been widely used to treat female diseases such as vaginal discharge, amenorrhea, and uterine bleeding, and recent pharmacological studies have also found that it has antioxidant, anti-inflammatory, and anti-tumor physiological activity, which has received more and more attention. AIM OF THE STUDY: The objective was to evaluate cytotoxicity and the acute, subacute toxicity, and in vitro antioxidant activity of S. vaninii crude polysaccharide (SVP). MATERIALS AND METHODS: The monosaccharide composition of SVP was determined by HPLC (high-performance liquid chromatography). The cytotoxicity of different concentrations of SVP on three types of cells (HT-22, Kupffer macrophages, HEK293) was assessed using CCk-8. The acute toxicity in vivo was evaluated for 14 days after the administration of SVP (2500,5000, or 10,000 mg/mL). For the evaluation of subacute toxicity, mice were daily treated for 28 days with SVP (2500,5000, or 10,000 mg/mL). In addition, DPPH, hydroxyl radical, and superoxide anion radical were used to evaluate the in vitro antioxidant activity of SVP. RESULTS: SVP was not toxic in all three cell lines tested. In vitro antioxidant tests on the extracts showed that SVP possessed a strong antioxidant capacity in vitro. In the acute study, the no-observed-adverse-effect level (NOAEL) in male and female rats was 10,000 mg/kg body weight. There were also no deaths or severe toxicity associated with SVP in subacute studies. However, SVP treatment had a decreasing effect on body weight in mice of both sexes (2500, 5000, and 10000 mg/kg). At doses (5000 and 10,000 mg/kg), SVP had a reduced effect on food intake in both male and female mice. In addition, there were significant effects on organ coefficients of the liver, lung, and kidney. Hematological analysis showed significantly lower LYM (%) values in mice of both sexes, with significantly lower MCH (pg) values obtained in males (5000 mg/kg and 10000 mg/kg) and higher GRAN (%) values in females. In addition, the RDW-SD (fL) values were significantly lower in the male mice given the highest dose. Biochemical tests showed that there were no significant changes in ALT, AST, TP, and Cr levels after SVP treatment. In histopathological analysis, mild liver toxicity was observed in both female mice treated with 10,000 mg/kg SVP. CONCLUSION: The extract of SVP showed a predominance of polysaccharide compounds, with non-toxic action in vivo. Our approach revealed SVP on the chemical composition and suggests a high margin of safety in the popular use of medicinal fungi. In conclusion, our results suggest that SVP is safe, and can be used as health care products and food.


Asunto(s)
Antioxidantes , Extractos Vegetales , Ratas , Ratones , Humanos , Masculino , Femenino , Animales , Antioxidantes/toxicidad , Extractos Vegetales/toxicidad , Células HEK293 , Pruebas de Toxicidad Aguda , Peso Corporal
12.
Elife ; 122023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38149844

RESUMEN

Insulin resistance (IR) is a complex metabolic disorder that underlies several human diseases, including type 2 diabetes and cardiovascular disease. Despite extensive research, the precise mechanisms underlying IR development remain poorly understood. Previously we showed that deficiency of coenzyme Q (CoQ) is necessary and sufficient for IR in adipocytes and skeletal muscle (Fazakerley et al., 2018). Here, we provide new insights into the mechanistic connections between cellular alterations associated with IR, including increased ceramides, CoQ deficiency, mitochondrial dysfunction, and oxidative stress. We demonstrate that elevated levels of ceramide in the mitochondria of skeletal muscle cells result in CoQ depletion and loss of mitochondrial respiratory chain components, leading to mitochondrial dysfunction and IR. Further, decreasing mitochondrial ceramide levels in vitro and in animal models (mice, C57BL/6J) (under chow and high-fat diet) increased CoQ levels and was protective against IR. CoQ supplementation also rescued ceramide-associated IR. Examination of the mitochondrial proteome from human muscle biopsies revealed a strong correlation between the respirasome system and mitochondrial ceramide as key determinants of insulin sensitivity. Our findings highlight the mitochondrial ceramide-CoQ-respiratory chain nexus as a potential foundation of an IR pathway that may also play a critical role in other conditions associated with ceramide accumulation and mitochondrial dysfunction, such as heart failure, cancer, and aging. These insights may have important clinical implications for the development of novel therapeutic strategies for the treatment of IR and related metabolic disorders.


Asunto(s)
Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Enfermedades Mitocondriales , Humanos , Ratones , Animales , Ubiquinona , Transporte de Electrón , Diabetes Mellitus Tipo 2/metabolismo , Ceramidas/metabolismo , Ratones Endogámicos C57BL , Músculo Esquelético/metabolismo , Enfermedades Mitocondriales/patología
13.
BMC Complement Med Ther ; 23(1): 402, 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37946127

RESUMEN

Malaria is a global health challenge with endemicity in sub-Saharan Africa, where there are multiple drug-resistant strains and limited access to modern health care facilities, especially in rural areas. Studies indicate that African traditional medicine could make a substantial contribution to the reduction of malaria-related deaths and achievement of universal health coverage (UHC), particularly in these regions. Thus, this study evaluated the curative antimalarial effects of Chromolaena odorata leaf extract using mouse model. Forty-five (45) albino mice weighing between 18 and 22 g were grouped into nine groups of 5 animals each. Animals in groups 2-9 were infected with the chloroquine-resistant strain of Plasmodium berghei, while animals in groups 3-9 were subsequently treated with 10 mg/kg chloroquine, a combination of 1.4 mg/kg artemether and 8.75 mg/kg lumefantrine (Coartem), and varying concentrations of the fraction from the aqueous leaf extract of C. odorata at day 3 post-infection. The findings from this study indicate that treatment with 400 mg/kg of the ethanolic fraction of the crude extract resulted in a significant decrease in parasite load (97.6%), which was comparable to the activities of the conventional drugs chloroquine (98.6%) and Coartem (98.8%). The ethyl acetate and ethanolic fractions at 400 mg/kg also ameliorated the significant alterations in the red blood cells, white blood cells, and platelets of the infected animals. The high antimalarial activity displayed by the ethanolic fraction could be due to the presence of quercetin and kaempferol, as detected by high performance liquid chromatography (HPLC) analysis. The findings suggest that the fractions from C. odorata could serve as an alternative source of malaria therapy, particularly in sub-Saharan Africa.


Asunto(s)
Antimaláricos , Chromolaena , Malaria , Animales , Ratones , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Chromolaena/química , Combinación Arteméter y Lumefantrina , Extractos Vegetales/química , Malaria/tratamiento farmacológico , Malaria/parasitología , Cloroquina/farmacología
14.
Molecules ; 28(22)2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-38005208

RESUMEN

The integration of phosphorus chemistry with the mechanism of ATP synthesis/hydrolysis requires dynamical information during ATP turnover and catalysis. Oxygen exchange reactions occurring at ß-catalytic sites of the FOF1-ATP synthase/F1-ATPase imprint a unique record of molecular events during the catalytic cycle of ATP synthesis/hydrolysis. They have been shown to provide valuable time-resolved information on enzyme catalysis during ATP synthesis and ATP hydrolysis. The present work conducts new experiments on oxygen exchange catalyzed by submitochondrial particles designed to (i) measure the relative rates of Pi-ATP, Pi-HOH, and ATP-HOH isotope exchanges; (ii) probe the effect of ADP removal on the extent of inhibition of the exchanges, and (iii) test their uncoupler sensitivity/resistance. The objectives have been realized based on new experiments on submitochondrial particles, which show that both the Pi-HOH and ATP-HOH exchanges occur at a considerably higher rate relative to the Pi-ATP exchange, an observation that cannot be explained by previous mechanisms. A unifying explanation of the kinetic data that rationalizes these observations is given. The experimental results in (ii) show that ADP removal does not inhibit the intermediate Pi-HOH exchange when ATP and submitochondrial particles are incubated, and that the nucleotide requirement of the intermediate Pi-HOH exchange is adequately met by ATP, but not by ADP. These results contradicts the central postulate in Boyer's binding change mechanism of reversible catalysis at a F1 catalytic site with Keq~1 that predicts an absolute requirement of ADP for the occurrence of the Pi-HOH exchange. The prominent intermediate Pi-HOH exchange occurring under hydrolytic conditions is shown to be best explained by Nath's torsional mechanism of energy transduction and ATP synthesis/hydrolysis, which postulates an essentially irreversible cleavage of ATP by mitochondria/particles, independent from a reversible formation of ATP from ADP and Pi. The explanation within the torsional mechanism is also shown to rationalize the relative insensitivity of the intermediate Pi-HOH exchange to uncouplers observed in the experiments in (iii) compared to the Pi-ATP and ATP-HOH exchanges. This is shown to lead to new concepts and perspectives based on ligand displacement/substitution and ligand permutation for the elucidation of the oxygen exchange reactions within the framework of fundamental phosphorus chemistry. Fast mechanisms that realize the rotation/twist, tilt, permutation and switch of ligands, as well as inversion at the γ-phosphorus synchronously and simultaneously and in a concerted manner, have been proposed, and their stereochemical consequences have been analyzed. These considerations take us beyond the binding change mechanism of ATP synthesis/hydrolysis in bioenergetics.


Asunto(s)
Fosforilación Oxidativa , Fósforo , Hidrólisis , Ligandos , Adenosina Trifosfato/metabolismo , Cinética , Oxígeno
15.
PeerJ ; 11: e15833, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37780388

RESUMEN

Background: The unconventional yeast species Yarrowia lipolytica is a valuable source of protein and many other nutrients. It can be used to produce hydrolytic enzymes and metabolites, including kynurenic acid (KYNA), an endogenous metabolite of tryptophan with a multidirectional effect on the body. The administration of Y. lipolytica with an increased content of KYNA in the diet may have a beneficial effect on metabolism, which was evaluated in a nutritional experiment on mice. Methods: In the dry biomass of Y. lipolytica S12 enriched in KYNA (high-KYNA yeast) and low-KYNA (control) yeast, the content of KYNA was determined by high-performance liquid chromatography. Then, proximate and amino acid composition and selected indicators of antioxidant status were compared. The effect of 5% high-KYNA yeast content in the diet on the growth, hematological and biochemical indices of blood and the redox status of the liver was determined in a 7-week experiment on adult male mice from an outbred colony derived from A/St, BALB/c, BN/a and C57BL/6J inbred strains. Results: High-KYNA yeast was characterized by a greater concentration of KYNA than low-KYNA yeast (0.80 ± 0.08 vs. 0.29 ± 0.01 g/kg dry matter), lower content of crude protein with a less favorable amino acid composition and minerals, higher level of crude fiber and fat and lower ferric-reducing antioxidant power, concentration of phenols and glutathione. Consumption of the high-KYNA yeast diet did not affect the cumulative body weight gain per cage, cumulative food intake per cage and protein efficiency ratio compared to the control diet. A trend towards lower mean corpuscular volume and hematocrit, higher mean corpuscular hemoglobin concentration and lower serum total protein and globulins was observed, increased serum total cholesterol and urea were noted. Its ingestion resulted in a trend towards greater ferric-reducing antioxidant power in the liver and did not affect the degree of liver lipid and protein oxidation. Conclusions: The improvement of the quality of Y. lipolytica yeast biomass with increased content of KYNA, including its antioxidant potential, would be affected by the preserved level of protein and unchanged amino acid profile. It will be worth investigating the effect of such optimized yeast on model animals, including animals with metabolic diseases.


Asunto(s)
Yarrowia , Masculino , Animales , Ratones , Antioxidantes/metabolismo , Ácido Quinurénico/metabolismo , Biomasa , Ratones Endogámicos C57BL , Aminoácidos/metabolismo
16.
Elife ; 122023 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-37843983

RESUMEN

Inositol hexakisphosphate kinases (IP6Ks) are emerging as relevant pharmacological targets because a multitude of disease-related phenotypes has been associated with their function. While the development of potent IP6K inhibitors is gaining momentum, a pharmacological tool to distinguish the mammalian isozymes is still lacking. Here, we implemented an analog-sensitive approach for IP6Ks and performed a high-throughput screen to identify suitable lead compounds. The most promising hit, FMP-201300, exhibited high potency and selectivity toward the unique valine gatekeeper mutants of IP6K1 and IP6K2, compared to the respective wild-type (WT) kinases. Biochemical validation experiments revealed an allosteric mechanism of action that was corroborated by hydrogen deuterium exchange mass spectrometry measurements. The latter analysis suggested that displacement of the αC helix, caused by the gatekeeper mutation, facilitates the binding of FMP-201300 to an allosteric pocket adjacent to the ATP-binding site. FMP-201300 therefore serves as a valuable springboard for the further development of compounds that can selectively target the three mammalian IP6Ks; either as analog-sensitive kinase inhibitors or as an allosteric lead compound for the WT kinases.


Asunto(s)
Fosfotransferasas (Aceptor del Grupo Fosfato) , Ácido Fítico , Animales , Fosfotransferasas (Aceptor del Grupo Fosfato)/genética , Fosfotransferasas (Aceptor del Grupo Fosfato)/metabolismo , Fosfatos de Inositol/metabolismo , Mamíferos/metabolismo
17.
Artículo en Inglés | MEDLINE | ID: mdl-37903028

RESUMEN

Background: Lipopolysaccharides (LPSs) are a component of certain types of bacteria and can induce an inflammatory response in the body, including in the pancreas. Cannabidiol (CBD), a nonpsychoactive compound found in cannabis, has been shown to have anti-inflammatory effects and may offer potential therapeutic benefits for conditions involving inflammation and damage. The aim of this study was to investigate any potential preventative effects of CBD on experimental LPS-induced pancreatic pathology in rats. Materials and Methods: Thirty-two rats were randomly divided into four groups as control, LPS (5 mg/kg, intraperitoneally [i.p.]), LPS+CBD, and CBD (5 mg/kg, i.p.) groups. Six hours after administering LPS, the rats were euthanized, and blood and pancreatic tissue samples were taken for biochemical, polymerase chain reaction (PCR), histopathological, and immunohistochemical examinations. Results: The results indicated that LPS decreased serum glucose levels and increased lipase levels. It also caused severe hyperemia, increased vacuolization in endocrine cells, edema, and slight inflammatory cell infiltrations at the histopathological examination. Insulin and amylin expressions decreased during immunohistochemical analyses. At the PCR analysis, Silent Information Regulator 2 homolog 1 and peroxisome proliferator-activated receptor gamma coactivator-1 alpha expressions decreased and tumor protein p53 expressions increased in the LPS group. CBD improved the biochemical, PCR, histopathological, and immunohistochemical results. Conclusions: The findings of the current investigation demonstrated that LPS damages both the endocrine and exocrine pancreas. However, CBD demonstrated marked ameliorative effects in the pancreas in LPS induced rat model pancreatitis.

18.
iScience ; 26(10): 107738, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37692288

RESUMEN

LAT1 (SLC7A5) is one of the most studied membrane transporters due to its relevance to physiology in supplying essential amino acids to brain and fetus, and to pathology being linked to nervous or embryo alterations; moreover, LAT1 over-expression is always associated with cancer development. Thus, LAT1 is exploited as a pro-drug vehicle and as a target for anti-cancer therapy. We here report the identification of a new substrate with pathophysiological implications, i.e., Cu-histidinate, and an unconventional uniport mechanism exploited for the Cu-histidinate transport. Crystals of the monomeric species Cu(His)2 were obtained in our experimental conditions and the actual transport of the complex was evaluated by a combined strategy of bioinformatics, site-directed mutagenesis, radiolabeled transport, and mass spectrometry analysis. The LAT1-mediated transport of Cu(His)2 may have profound implications for both the treatment of copper dysmetabolism diseases, such as the rare Menkes disease, and of cancer as an alternative to platinum-based therapies.

19.
Front Vet Sci ; 10: 1259426, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37771941

RESUMEN

Although antibiotics growth promoters (AGPs), including zinc-bacitracin (ZnB), can threaten human health due to developing antimicrobial resistance, as well as drug residue in animal and poultry products, ZnB is still widely used, particularly in developing countries, for the sustainability of poultry farming. The present investigation aims to assess the use of Saccharomyces cerevisiae and Lactobacillus acidophilus, with or without a prebiotic (mannooligosaccharide, MOS), as alternatives to ZnB. For this reason, 150 one-day-old chicks were grouped into six groups, designated negative control, LA, SC, ZnB, SA + MOS, and LA + MOS (5 replicates of 5 chicks for each group). Chicks kept in the control group were fed the basal diet. Chickens kept in LA and SC groups received L. acidophilus, S. cerevisiae at a 1 g/kg diet and 2 g/Kg, respectively. Chickens kept in ZnB received ZnB at 0.5 g/kg. Chicks kept in the SC + MOS and LA + MOS were fed a basal diet containing 2 g S. cerevisiae + 1 g MOS/kg or 1 g L. acidophilus + 1 g MOS /kg, respectively. The efficacy was assessed based on the growth performance, carcass traits, meat quality, nutrient digestibility, and blood biochemistry composition during the entire trial 1-36 days of age. Results showed that chicks kept in the SC group had greater BW than the control (p < 0.05). Chicks kept in the SC, LA, SC + MOS, and LA + MOS consumed less feed than the control and Zn-B groups (p < 0.05). Supplementation with S. cerevisiae resulted in a better (p < 0.05) feed conversion rate (FCR) than the control group. Supplementation with L. acidophilus + MOS significantly increased (p < 0.05) the relative liver weight compared to those supplemented with ZnB, S. cerevisiae, and L. acidophilus. In addition, supplementation with ZnB-induced spleen hypertrophy compared to S. cerevisiae and L. acidophilus-supplemented groups (p < 0.05). Plasma, meat, and liver cholesterol, as well as the cholesterol-to-lipid ratio of meat and liver, were significantly decreased (p < 0.05) in both SC and LA groups compared to the control group. Our research indicates that adding 2 g/kg of S. cerevisiae to broiler feed can effectively replace ZnB and enhance productive performance and economic profits, making it a viable and sustainable option for broiler farming.

20.
J Paediatr Child Health ; 59(10): 1140-1145, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37545420

RESUMEN

AIM: To characterise parathyroid hormone (PTH) concentrations in infants at high risk for metabolic bone disease, in order to assist clinical decisions around the use of PTH for screening. METHODS: Infants born under 28 weeks' postmenstrual age or with birthweight under 1.5 kg in a tertiary neonatal unit in the UK were included. Clinical guidance was to assess PTH concentration in the first 3 weeks after birth. Clinical information was extracted from prospective records. RESULTS: Sixty-four infants had mean birth gestation of 26 weeks and birthweight of 882 g. Median PTH (sent on median day 18 of life) was 9.2 pmol/L (interquartile range 5.3-17 pmol/L). Sixty-seven per cent of infants had a PTH greater than 7 pmol/L. For 22% of the infants, raised PTH was not accompanied by abnormal phosphate or alkaline phosphatase. Eighty-nine per cent of infants tested were insufficient or deficient for 25-hydroxyvitamin D. CONCLUSIONS: Universal screening highlights the high frequency of high PTH in this high-risk population, implying a need for calcium supplementation. A considerable number of infants would not be identified as showing potential signs of metabolic bone disease if the assessment excludes the use of PTH. The high level of 25-hydroxyvitamin D deficiency may be a confounder.

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