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Frontiers in Bioscience (Landmark... Jun 2024Under fasting conditions, the pathway converting gluconeogenesis precursors into muscle glycogen becomes crucial due to reduced glycogen reserves. However, there is...
BACKGROUND
Under fasting conditions, the pathway converting gluconeogenesis precursors into muscle glycogen becomes crucial due to reduced glycogen reserves. However, there is limited research on skeletal muscle gluconeogenesis and the impact of fasting on gluconeogenic gene expression.
METHODS
Sheep fetal skeletal muscle cells cultured were used to study the effects of varying lactic acid concentrations (0 to 30 mM) and 2.5 mM glucose on the expression of gluconeogenesis-related genes after 6 h of fasting. The effects on mRNA and protein expression of key genes involved in skeletal muscle gluconeogenesis were measured by quantitative real time polymerase chain reaction (qRT-PCR), immunofluorescence, and western blotting at 48 h.
RESULTS
Fasting increased the expression of key gluconeogenic genes, fructose-1,6-bisphosphatase 2 (), glucose-6-phosphatase 3 (), pyruvate kinase M (), monocarboxylate transporter1 (), glucose transporter type 4 (), pyruvate carboxylase (), and lactate dehydrogenase A (). The mRNA levels of , , and significantly decreased with glucose addition. Additionally, 10 mM lactic acid significantly promoted the expression of , , , , , and while inhibiting phosphoenolpyruvate carboxykinase () expression. At the protein level, 10 mM lactic acid significantly increased FBP2 and PKM protein expression.
CONCLUSIONS
This study shows that fasting regulates key gluconeogenic gene expression in sheep skeletal muscle cells and highlights the role of lactic acid in inducing these gene expressions.
Topics: Animals; Gluconeogenesis; Sheep; Muscle, Skeletal; Gene Expression Regulation; Glucose; Cells, Cultured; Lactic Acid; Fructose-Bisphosphatase
PubMed: 38940053
DOI: 10.31083/j.fbl2906237 -
Frontiers in Bioscience (Landmark... Jun 2024The endoplasmic reticulum (ER) played an important role in the folding, assembly and post-translational modification of proteins. ER homeostasis could be disrupted by... (Review)
Review
The endoplasmic reticulum (ER) played an important role in the folding, assembly and post-translational modification of proteins. ER homeostasis could be disrupted by the accumulation of misfolded proteins, elevated reactive oxygen species (ROS) levels, and abnormal Ca2+ signaling, which was referred to ER stress (ERS). Ferroptosis was a unique programmed cell death model mediated by iron-dependent phospholipid peroxidation and multiple signaling pathways. The changes of mitochondrial structure, the damage of glutathione peroxidase 4 (GPX4) and excess accumulation of iron were the main characteristics of ferroptosis. ROS produced by ferroptosis can interfere with the activity of protein-folding enzymes, leading to the accumulation of large amounts of unfolded proteins, thus causing ERS. On the contrary, the increase of ERS level could promote ferroptosis by the accumulation of iron ion and lipid peroxide, the up-regulation of ferroptosis related genes. At present, the studies on the relationship between ferroptosis and ERS were one-sided and lack of in-depth studies on the interaction mechanism. This review aimed to explore the molecular mechanism of cross-talk between ferroptosis and ERS, and provide new strategies and targets for the treatment of liver diseases.
Topics: Ferroptosis; Humans; Endoplasmic Reticulum Stress; Liver Diseases; Reactive Oxygen Species; Animals; Signal Transduction; Iron; Lipid Peroxidation; Endoplasmic Reticulum
PubMed: 38940044
DOI: 10.31083/j.fbl2906221 -
Frontiers in Bioscience (Landmark... Jun 2024The inhibitors of mammalian target of rapapmycin (mTOR), everolimus, temsirolimus and rapamycin, have a wide range of clinical utility; however, as is inevitably the... (Review)
Review
The inhibitors of mammalian target of rapapmycin (mTOR), everolimus, temsirolimus and rapamycin, have a wide range of clinical utility; however, as is inevitably the case with other chemotherapeutic agents, resistance development constrains their effectiveness. One putative mechanism of resistance is the promotion of autophagy, which is a direct consequence of the inhibition of the mTOR signaling pathway. Autophagy is primarily considered to be a cytoprotective survival mechanism, whereby cytoplasmic components are recycled to generate energy and metabolic intermediates. The autophagy induced by everolimus and temsirolimus appears to play a largely protective function, whereas a cytotoxic function appears to predominate in the case of rapamycin. In this review we provide an overview of the autophagy induced in response to mTOR inhibitors in different tumor models in an effort to determine whether autophagy targeting could be of clinical utility as adjuvant therapy in association with mTOR inhibition.
Topics: Humans; Autophagy; TOR Serine-Threonine Kinases; MTOR Inhibitors; Animals; Neoplasms; Signal Transduction; Antineoplastic Agents; Cytoprotection; Sirolimus
PubMed: 38940039
DOI: 10.31083/j.fbl2906231 -
Frontiers in Bioscience (Landmark... May 2024Phosphine resistance in challenges grain storage. This study investigates the impact of cytochrome P450 (CYP) enzymes and CYP346 family genes on phosphine resistance in...
BACKGROUND
Phosphine resistance in challenges grain storage. This study investigates the impact of cytochrome P450 (CYP) enzymes and CYP346 family genes on phosphine resistance in Indian Tribolium castaneum populations.
METHODS
Seven field populations of were compared with Lab- susceptible population for their resistance to phosphine. The levels of cytochrome P450 enzyme and expression of certain CYP346 family genes were tracked in these populations.
RESULTS
The highly resistant Patiala population showed significantly increased CYP450 activity (11.26 ± 0.14 nmol/min/mg protein, 7.41-fold higher) compared to the lab-susceptible population (1.52 ± 0.09 nmol/min/mg protein) when assayed using 8 mM p-nitroanisole as the substrate. The mRNA expression was measured relative to the standard gene and revealed significant upregulation of and in highly resistant populations Moga and Patiala (: 12.09 ± 2.19 to 21.74 ± 3.82; : 59.097 ± 10.265 to 50.148 ± 8.272). Patiala's exhibited an impressive 685.76-fold change, and Moga's showed a 361.893-fold change compared to lab-susceptible. Linear regression confirmed robust fits for each gene (R2: 0.693 to 0.756). Principal component analysis (PCA) demonstrated a strong positive correlation between genes expression; and cytochrome P450 activity. Patiala, Moga, and Hapur populations showed conformity, associating higher resistance with increased P450 activity and CYP346 gene expression. Cluster analysis highlighted a potential correlation between , , and and P450 activity, with Patiala and Moga clustering together.
CONCLUSIONS
Variability in and in strong resistance populations may contribute to adaptation and resistance mechanisms. The study provides insights into specific CYP346 family genes associated with phosphine resistance, emphasizing the intricate interaction between CYP450 detoxifying enzymes, CYP346 family genes, and resistance mechanisms. The upregulation of genes suggests a survival advantage for against phosphine, diminishing phosphine's efficacy as a pest control measure.
Topics: Tribolium; Cytochrome P-450 Enzyme System; Insecticide Resistance; Phosphines; Insecticides; India; Animals
PubMed: 38940033
DOI: 10.31083/j.fbl2906203 -
Frontiers in Bioscience (Landmark... Jun 2024This study investigated the impact of salvianolic acids, derived from Danshen, on melanoma cell growth. Specifically, we assessed the ability of salvianolic acid A (Sal...
BACKGROUND
This study investigated the impact of salvianolic acids, derived from Danshen, on melanoma cell growth. Specifically, we assessed the ability of salvianolic acid A (Sal A) to modulate melanoma cell proliferation.
METHODS
We used human melanoma A2058 and A375 cell lines to investigate the effects of Sal A on cell proliferation and death by measuring bromodeoxyuridine incorporation and lactate dehydrogenase release. We assessed cell viability and cycle progression using water soluble tetrazolium salt-1 (WST-1) mitochondrial staining and propidium iodide. Additionally, we used a phospho-kinase array to investigate intracellular kinase phosphorylation, specifically measuring the influence of Sal A on checkpoint kinase-2 (Chk-2) via western blot analysis.
RESULTS
Sal A inhibited the growth of A2058 and A375 cells dose-responsively and induced cell cycle arrest at the G2/M phase. Notably, Sal A selectively induces Chk-2 phosphorylation without affecting Chk-1, thereby degrading Chk-2-regulated genes and . However, Sal A does not affect the Chk1-Cdc25C pathway.
CONCLUSIONS
Salvianolic acids, especially Sal A, effectively hinder melanoma cell growth by inducing Chk-2 phosphorylation and disrupting G2/M checkpoint regulation.
Topics: Humans; Checkpoint Kinase 2; cdc25 Phosphatases; Melanoma; Cell Line, Tumor; Cell Proliferation; Lactates; Caffeic Acids; Signal Transduction; Phosphorylation; Cell Survival
PubMed: 38940031
DOI: 10.31083/j.fbl2906213 -
Frontiers in Bioscience (Landmark... Jun 2024Apricot kernels containing amygdalin (AMG) as the major cyanogenic glycoside are potentially useful as a complementary therapy for the management of several ailments...
BACKGROUND
Apricot kernels containing amygdalin (AMG) as the major cyanogenic glycoside are potentially useful as a complementary therapy for the management of several ailments including cancer. Nevertheless, little is known regarding the toxic and therapeutic doses of AMG, particularly in terms of male reproduction. Hence, this study evaluates selected qualitative characteristics of rabbit testicular tissue following administration of AMG or apricot kernels for 28 days.
METHODS
The rabbits were randomly divided into five groups (Control, P1, P2, P3, P4). The Control received no AMG/apricot kernels while the experimental groups P1 and P2 received a daily intramuscular injection of amygdalin at a dose of 0.6 and 3.0 mg/kg of body weight (b.w.) for 28 days, respectively. P3 and P4 received a daily dose of 60 and 300 mg/kg b.w. of crushed apricot kernels mixed with feed for 28 days, respectively. Changes to the testicular structure were quantified morphometrically, while tissue lysates were subjected to the evaluation of reactive oxygen species (ROS) production, total antioxidant capacity, activities of antioxidant enzymes, and glutathione concentration. The extent of damage to the proteins and lipids was quantified as well. Levels of selected cytokines were determined by the enzyme-linked immunosorbent assay while a luminometric approach was used to assess the activity of caspases.
RESULTS
Rabbits treated with 3.0 mg/kg b.w. AMG presented a significantly increased protein oxidation ( = 0.0118) accompanied by a depletion of superoxide dismutase ( = 0.0464), catalase ( = 0.0317), and glutathione peroxidase ( = 0.0002). Significantly increased levels of interleukin-1 beta ( = 0.0012), tumor necrosis factors alpha ( = 0.0159), caspase-3/7 ( = 0.0014), and caspase-9 ( = 0.0243) were also recorded in the experimental group P2 when compared to the Control. No effects were observed in the rabbits treated with apricot kernels at the oxidative, inflammatory, and histopathological levels.
CONCLUSIONS
Apricot kernels did not induce toxicity in the testicular tissues of male rabbits, unlike pure AMG, which had a negative effect on male reproductive structures carried out through oxidative, inflammatory, and pro-apoptotic mechanisms.
Topics: Animals; Male; Rabbits; Testis; Amygdalin; Prunus armeniaca; Oxidative Stress; Reactive Oxygen Species; Antioxidants; Inflammation
PubMed: 38940029
DOI: 10.31083/j.fbl2906235 -
Frontiers in Bioscience (Landmark... May 2024Osteosarcoma (OS) is a primary malignant bone tumor in the pediatric and adolescent populations. Long non-coding RNAs (LncRNAs), such as plasma-cytoma variant...
BACKGROUND
Osteosarcoma (OS) is a primary malignant bone tumor in the pediatric and adolescent populations. Long non-coding RNAs (LncRNAs), such as plasma-cytoma variant translocation 1 (PVT1), have emerged as significant regulators of OS metastasis. Recent studies have indicated that activation of signal transducer and activator of transcription 3 (STAT3) signaling, which might be controlled by PVT1, inhibits ferroptosis to promote the malignant progression of cancer. Therefore, the present study aimed to determine the role of PVT1 in OS pathogenesis and investigate whether PVT1 affects OS progression by regulating STAT3/GPX4 pathway-mediated ferroptosis.
METHODS
The human OS cell line MG63 were transfected with sh-PVT1 plasmid to inhibit PVT1 expression, with or without co-transfection with a STAT3 overexpression plasmid. The expression of PVT1 was determined by real-time quantitative polymerase chain reaction (RT-qPCR). The proliferation, migration, invasion, and apoptosis of MG63 cells were determined using the cell counting kit-8 (CCK8), Transwell assay, and flow cytometry. The levels of malondialdehyde (MDA), Fe2+, and glutathione (GSH) were determined by ELISA kits, whereas reactive oxygen species (ROS) level was determined by immunofluorescence. The protein expression levels of STAT3, p-STAT3, and glutathione peroxidase 4 (GPX4) were detected by western blot (WB).
RESULTS
PVT1 expression was significantly increased in MG63 cells. When knocking down PVT1 with sh-PVT1 plasmid, the proliferation, migration, and invasion of MG63 cells were markedly inhibited, while the rate of apoptosis was upregulated. Further investigation revealed that MG63 cells with PVT1 knockdown exhibited elevated levels of MDA, Fe2+, and ROS. In addition, the inhibition of PVT1 expression resulted in decreased levels of GSH and inhibited expression of p-STAT3 and GPX4. When sh-PVT1 was co-transfected with STAT3 overexpression plasmid in MG63 cells, the increased levels of MDA, Fe2+, and ROS were downregulated, and the decreased expressions of GSH, p-STAT3, and GPX4 were upregulated.
CONCLUSION
PVT1 promotes OS metastasis by activating the STAT3/GPX4 pathway to inhibit ferroptosis. Targeting PVT1 might be a novel therapeutic strategy for OS treatment.
Topics: Humans; Osteosarcoma; RNA, Long Noncoding; Ferroptosis; STAT3 Transcription Factor; Cell Line, Tumor; Bone Neoplasms; Phospholipid Hydroperoxide Glutathione Peroxidase; Cell Proliferation; Reactive Oxygen Species; Signal Transduction; Cell Movement; Disease Progression; Apoptosis; Gene Expression Regulation, Neoplastic
PubMed: 38940027
DOI: 10.31083/j.fbl2906207 -
Frontiers in Bioscience (Landmark... Jun 2024Nonalcoholic fatty liver disease (NAFLD) is a prevalent condition characterized by hepatic fat accumulation, often progressing to severe liver injury, for which approved...
BACKGROUND
Nonalcoholic fatty liver disease (NAFLD) is a prevalent condition characterized by hepatic fat accumulation, often progressing to severe liver injury, for which approved treatments are currently lacking. This study explores the potential therapeutic impact of alpha-lipoic acid (ALA), a natural compound crucial in lipid metabolism, on NAFLD using an model.
METHODS
HepG2 cells were treated with a palmitic acid:oleic acid (PA:OA) mixture, representing a cellular model of steatosis. Subsequent treatment with ALA at concentrations of 1 µM and 5 µM aimed to evaluate its effects on lipid content and metabolism. Real-time polymerase chain reaction (PCR), BODIPY staining, cytofluorimetric analysis, and lipidomics were used to assess gene expression, lipid droplet accumulation, and fatty acid profiles.
RESULTS
Our results showed that ALA significantly reduced lipid droplets in PA:OA-treated HepG2 cells, with a concentration-dependent effect. Analysis of fatty acid profiles demonstrated a decrease in palmitic acid levels with ALA treatment, while oleic acid reduction was observed only at the higher concentration. Moreover, ALA modulated the expression of genes involved in cholesterol biosynthesis and low-density lipoprotein (LDL) metabolism, indicating a potential role in lipid homeostasis. Further insights into molecular mechanisms revealed that ALA modulated peroxisome proliferator activated receptors (PPARs), specifically PPAR-alpha and PPAR-gamma, involved in fatty acid metabolism and insulin sensitivity. Finally, ALA counteracted the overexpression of thermogenic genes induced by exogenous fatty acids, suggesting a regulatory role in energy dissipation pathways.
CONCLUSION
In conclusion, this study highlights ALA as a therapeutic agent in mitigating lipid accumulation and dysregulation in NAFLD.
Topics: Humans; Thioctic Acid; Hep G2 Cells; Lipid Metabolism; Non-alcoholic Fatty Liver Disease; Oleic Acid; Palmitic Acid; Gene Expression Regulation; Fatty Acids; PPAR gamma; Lipid Droplets; PPAR alpha; Uncoupling Protein 2
PubMed: 38940024
DOI: 10.31083/j.fbl2906209 -
Frontiers in Bioscience (Scholar... Jun 2024Several inherited metabolic fatty acid disorders present with myopathies. Skeletal muscle accounts for 40% of the body and is important for metabolism, exercise, and... (Review)
Review
Several inherited metabolic fatty acid disorders present with myopathies. Skeletal muscle accounts for 40% of the body and is important for metabolism, exercise, and movement. Muscle energy failure is manifested by metabolic crises with muscle weakness, sometimes associated with muscle fatigue and failure resulting in acute necrosis or rhabdomyolysis/myoglobinuria episodes. Lack of energy leads to muscle necrosis. Other presentations are weakness and myalgias with lipid storage myopathies in the biopsy. The biomarkers of such disorders are acyl-carnitine with various profiles and need to be carefully evaluated to plan supplementary therapy and specific diets. If red flags are not distinctly followed and diagnosed in time they might lead to a metabolic or cardiac failure.
Topics: Humans; Muscular Diseases; Carnitine; Lipid Metabolism, Inborn Errors; Muscle, Skeletal; Muscular Dystrophies
PubMed: 38939976
DOI: 10.31083/j.fbs1602012 -
Journal of Global Health Jun 2024Malaria infection during pregnancy is associated with an increased risk of maternal death, as well as adverse birth outcomes. Intermittent preventive treatment in...
BACKGROUND
Malaria infection during pregnancy is associated with an increased risk of maternal death, as well as adverse birth outcomes. Intermittent preventive treatment in pregnancy with sulfadoxine-pyrimethamine (IPTp-SP) is known to improve pregnancy outcomes. However, the coverage of IPTp-SP in antenatal care (ANC) in sub-Saharan Africa remains well below the target. This study aims to estimate to what extent malaria service readiness affects the uptake of IPTp-SP during ANC visits in sub-Saharan African countries.
METHODS
This study included 3267 pregnant women attending ANC for the first time and 2797 pregnant women who had attended ANC more than a month ago in six sub-Saharan African countries. The readiness of malaria services at each institution includes four indicators: the presence of IPTp-SP guidelines, SP availability, integration of IPTp-SP service into ANC, and provider training on IPTp-SP. The outcome variable indicates whether a pregnant woman received IPTp-SP at her current ANC visit. A modified Poisson regression model estimated the associations between malaria service readiness and IPTp-SP uptake for women eligible for the first and subsequent doses.
RESULTS
For women eligible for their first dose, visiting an institution with available SP was associated with an increased probability of receiving IPTp-SP (risk ratio (RR) = 1.43; 95% confidence interval (CI) = 1.22 to 1.67, P < 0.001). For women who were eligible for their next dose, the availability of SP (RR = 1.17; 95% CI = 1.04 to 1.32, P = 0.008) and integration of IPTp-SP service into ANC (RR = 1.82; 95% CI = 1.21 to 2.74, P = 0.004) in the institution were associated with increased likelihood of IPTp-SP uptake. Counterfactual predictions indicated that enhanced provider training could boost IPTp-SP uptake in high-uptake countries, while better SP availability and IPTp-SP integration into ANC would significantly impact low-uptake countries.
CONCLUSIONS
For better IPTp-SP coverage, strategies should be customised. High uptake countries should focus on provider training, while low uptake ones should ensure IPTp-SP availability and service integration.
Topics: Humans; Female; Pregnancy; Antimalarials; Africa South of the Sahara; Pyrimethamine; Sulfadoxine; Malaria; Pregnancy Complications, Parasitic; Adult; Drug Combinations; Prenatal Care; Young Adult; Adolescent; Patient Acceptance of Health Care
PubMed: 38939971
DOI: 10.7189/jogh.14.04112