Intracellular Levels Research Articles

ROS formation, mitochondrial potential and osmotic stability of the lamprey red blood cells: effect of adrenergic stimulation and hypoosmotic stress.

Semi-anadromous animals experience salinity fluctuations during their life-span period. Alterations of environmental conditions induce stress response where catecholamines (CA) play a central role. Physiological stress and changes in external and internal osmolarity are frequently associated with increased production of reactive oxygen species (ROS). In this work, we studied the involvement of the cAMP/PKA pathway in mediating catecholamine-dependent effects on osmoregulatory responses, intracellular production of ROS, and mitochondrial membrane potential of the river lamprey (Lampetra fluviatilis, Linnaeus, 1758) red blood cells (RBCs). We also investigated the role of hypoosmotic shock in the process of ROS production and mitochondrial respiration of RBCs. For this, osmotic stability and the dynamics of the regulatory volume decrease (RVD) following hypoosmotic swelling, intracellular ROS levels, and changes in mitochondrial membrane potential were assessed in RBCs treated with epinephrine (Epi, 25 μM) and forskolin (Forsk, 20 μM). Epi and Forsk markedly reduced the osmotic stability of the lamprey RBCs whereas did not affect the dynamics of the RVD response in a hypoosmotic environment. Activation of PKA with Epi and Forsk increased ROS levels and decreased mitochondrial membrane potential of the lamprey RBCs. In contrast, upon hypoosmotic shock enhanced ROS production in RBCs was accompanied by increased mitochondrial membrane potential. Overall, a decrease in RBC osmotic stability and the enhancement of ROS formation induced by β-adrenergic stimulation raises concerns about stress-associated changes in RBC functions in agnathans. Increased ROS production in RBCs under hypoosmotic shock indicates that a decrease in blood osmolarity may be associated with oxidative damage of RBCs during lamprey migration.

Interleukin-4 protects retinal ganglion cells and promotes axon regeneration

BackgroundThe preservation of retinal ganglion cells (RGCs) and the facilitation of axon regeneration are crucial considerations in the management of various vision-threatening disorders. Therefore, we investigate the efficacy of interleukin-4 (IL-4), a potential therapeutic agent, in promoting neuroprotection and axon regeneration of retinal ganglion cells (RGCs) as identified through whole transcriptome sequencing in an in vitro axon growth model.MethodsA low concentration of staurosporine (STS) was employed to induce in vitro axon growth. Whole transcriptome sequencing was utilized to identify key target factors involved in the molecular mechanism underlying axon growth. The efficacy of recombinant IL-4 protein on promoting RGC axon growth was validated through in vitro experiments. The protective effect of recombinant IL-4 protein on somas of RGCs was assessed using RBPMS-specific immunofluorescent staining in mouse models with optic nerve crush (ONC) and N-methyl-D-aspartic acid (NMDA) injury. The protective effect on RGC axons was evaluated by anterograde labeling of cholera toxin subunit B (CTB), while the promotion of RGC axon regeneration was assessed through both anterograde labeling of CTB and immunofluorescent staining for growth associated protein-43 (GAP43).ResultsWhole-transcriptome sequencing of staurosporine-treated 661 W cells revealed a significant upregulation in intracellular IL-4 transcription levels during the process of axon regeneration. In vitro experiments demonstrated that recombinant IL-4 protein effectively stimulated axon outgrowth. Subsequent immunostaining with RBPMS revealed a significantly higher survival rate of RGCs in the rIL-4 group compared to the vehicle group in both NMDA and ONC injury models. Axonal tracing with CTB confirmed that recombinant IL-4 protein preserved long-distance projection of RGC axons, and there was a notably higher number of surviving axons in the rIL-4 group compared to the vehicle group following NMDA-induced injury. Moreover, intravitreal delivery of recombinant IL-4 protein substantially facilitated RGC axon regeneration after ONC injury.ConclusionThe recombinant IL-4 protein exhibits the potential to enhance the survival rate of RGCs, protect RGC axons against NMDA-induced injury, and facilitate axon regeneration following ONC. This study provides an experimental foundation for further investigation and development of therapeutic agents aimed at protecting the optic nerve and promoting axon regeneration.

Bortezomib elevates intracellular free Fe2+ by enhancing NCOA4-mediated ferritinophagy and synergizes with RSL-3 to inhibit multiple myeloma cells.

Iron contributes to tumor initiation and progression; however, excessive intracellular free Fe2+ can be toxic to cancer cells. Our findings confirmed that multiple myeloma (MM) cells exhibited elevated intracellular iron levels and increased ferritin, a key protein for iron storage, compared with normal cells. Interestingly, Bortezomib (BTZ) was found to trigger ferritin degradation, increase free intracellular Fe2+, and promote ferroptosis in MM cells. Subsequent mechanistic investigation revealed that BTZ effectively increased NCOA4 levels by preventing proteasomal degradation in MM cells. When we knocked down NCOA4 or blocked autophagy using chloroquine, BTZ-induced ferritin degradation and the increase in intracellular free Fe2+ were significantly reduced in MM cells, confirming the role of BTZ in enhancing ferritinophagy. Furthermore, the combination of BTZ with RSL-3, a specific inhibitor of GPX4 and inducer of ferroptosis, synergistically promoted ferroptosis in MM cell lines and increased cell death in both MM cell lines and primary MM cells. The induction of ferroptosis inhibitor liproxstatin-1 successfully counteracted the synergistic effect of BTZ and RSL-3 in MM cells. Altogether, our findings reveal that BTZ elevates intracellular free Fe2+ by enhancing NCOA4-mediated ferritinophagy and synergizes with RSL-3 by increasing ferroptosisin MM cells.

The γ-glutamyl cycle serves as an amino acids supply system in colorectal cancer organoids under chronic hypoxia

Malignant tumors are characterized by a hypoxic microenvironment, and metabolic reprogramming is necessary to ensure energy production and oxidative stress resistance. Although the microenvironmental properties of tumors vary under acute and chronic hypoxia, studies on chronic hypoxia-induced metabolic changes are limited. In the present study, we performed a comprehensive metabolic analysis in a chronic hypoxia model using colorectal cancer (CRC) organoids, and identified an amino acid supply system through the γ-glutamyl cycle, a glutathione recycling pathway. We analyzed the metabolic changes caused by hypoxia over time and observed that chronic hypoxia resulted in an increase in 5-oxoproline and a decrease in oxidized glutathione (GSSG) compared to acute hypoxia. These findings suggest that chronic hypoxia induces metabolic changes in the γ-glutamyl cycle. Moreover, inhibition of the γ-glutamyl cycle via γ-glutamyl cyclotransferase (GGCT) and γ-glutamyl transferase 1 (GGT1) knockdown significantly reversed chronic hypoxia-induced upregulation of 5-oxoproline and several amino acids. Notably, GGT1 knockdown downregulated the intracellular levels of γ-glutamyl amino acids. Conclusively, these results indicate that the γ-glutamyl cycle serves as an amino acid supply system in CRC under chronic hypoxia, which provides fresh insight into cancer metabolism under chronic hypoxia.

γ-Oryzanol from Rice Bran Antagonizes Glutamate-Induced Excitotoxicity in an In Vitro Model of Differentiated HT-22 Cells.

The excessive activation of glutamate in the brain is a factor in the development of vascular dementia. γ-Oryzanol is a natural compound that has been shown to enhance brain function, but more research is needed to determine its potential as a treatment for vascular dementia. This study investigated if γ-oryzanol can delay or improve glutamate neurotoxicity in an in vitro model of differentiated HT-22 cells and explored its neuroprotective mechanisms. The differentiated HT-22 cells were treated with 0.1 mmol/L glutamate for 24 h then given γ-oryzanol at appropriate concentrations or memantine (10 µmol/L) for another 24 h. Glutamate produced reactive oxygen species and depleted glutathione in the cells, which reduced their viability. Mitochondrial dysfunction was also observed, including the inhibition of mitochondrial respiratory chain complex I activity, the collapse of mitochondrial transmembrane potential, and the reduction of intracellular ATP levels in the HT-22 cells. Calcium influx triggered by glutamate subsequently activated type II calcium/calmodulin-dependent protein kinase (CaMKII) in the HT-22 cells. The activation of CaMKII-ASK1-JNK MAP kinase cascade, decreased Bcl-2/Bax ratio, and increased Apaf-1-dependent caspase-9 activation were also observed due to glutamate induction, which were associated with increased DNA fragmentation. These events were attenuated when the cells were treated with γ-oryzanol (0.4 mmol/L) or the N-methyl-D-aspartate receptor antagonist memantine. The results suggest that γ-oryzanol has potent neuroprotective properties against glutamate excitotoxicity in differentiated HT-22 cells. Therefore, γ-oryzanol could be a promising candidate for the development of therapies for glutamate excitotoxicity-associated neurodegenerative diseases, including vascular dementia.

The Role of PNPLA3_rs738409 Gene Variant, Lifestyle Factors, and Bioactive Compounds in Nonalcoholic Fatty Liver Disease: A Population-Based and Molecular Approach towards Healthy Nutrition.

This study aimed to investigate the impact of a common non-synonymous gene variant (C>G, rs738409) in patatin-like phospholipase domain-containing 3 (PNPLA3), leading to the substitution of isoleucine with methionine at position 148 (PNPLA3-I148M), on susceptibility to nonalcoholic fatty liver disease (NAFLD) and explore potential therapeutic nutritional strategies targeting PNPLA3. It contributed to understanding sustainable dietary practices for managing NAFLD, recently referred to as metabolic-dysfunction-associated fatty liver. NAFLD had been diagnosed by ultrasound in a metropolitan hospital-based cohort comprising 58,701 middle-aged and older Korean individuals, identifying 2089 NAFLD patients. The interaction between PNPLA3 and lifestyle factors was investigated. In silico analyses, including virtual screening, molecular docking, and molecular dynamics simulations, were conducted to identify bioactive compounds from foods targeting PNPLA3(I148M). Subsequent cellular experiments involved treating oleic acid (OA)-exposed HepG2 cells with selected bioactive compounds, both in the absence and presence of compound C (AMPK inhibitor), targeting PNPLA3 expression. Carriers of the risk allele PNPLA3_rs738409G showed an increased association with NAFLD risk, particularly with adherence to a plant-based diet, avoidance of a Western-style diet, and smoking. Delphinidin 3-caffeoyl-glucoside, pyranocyanin A, delta-viniferin, kaempferol-7-glucoside, and petunidin 3-rutinoside emerged as potential binders to the active site residues of PNPLA3, exhibiting a reduction in binding energy. These compounds demonstrated a dose-dependent reduction in intracellular triglyceride and lipid peroxide levels in HepG2 cells, while pretreatment with compound C showed the opposite trend. Kaempferol-7-glucoside and petunidin-3-rutinoside showed potential as inhibitors of PNPLA3 expression by enhancing AMPK activity, ultimately reducing intrahepatic lipogenesis. In conclusion, there is potential for plant-based diets and specific bioactive compounds to promote sustainable dietary practices to mitigate NAFLD risk, especially in individuals with genetic predispositions.

Curcumin reduces myocardial ischemia-reperfusion injury, by increasing endogenous H2S levels and further modulating m6A.

Our previous research shows that Curcumin (CUR) attenuates myocardial ischemia-reperfusion injury (MIRI) by reducing intracellular total RNA m6A levels. However, the mechanism remains unknown. For ischemia-reperfusion (IR), H9c2 cells were cultured for 6h in serum-free low-glycemic (1g/L) medium and a gas environment without oxygen, and then cultured for 6h in high-glycemic (4.5g/L) medium supplemented with 10% FBS and a 21% oxygen environment. The effects of different concentrations of CUR (5, 10, and 20 µM) treatments on signaling molecules in conventionally cultured and IR-treated H9c2 cells were examined. CUR treatment significantly up-regulated the H2S levels, and the mRNA and protein expression of cystathionine γ-lyase (CSE), and down-regulated the mRNAs and proteins levels of thiosulfate sulfurtransferase (TST) and ethylmalonic encephalopathy 1 (ETHE1) in H9c2 cells conventionally cultured and subjected to IR. Exogenous H2S supply (NaHS and GYY4137) significantly reduced intracellular total RNA m6A levels, and the expression of RNA m6A "writers" METTL3 and METTL14, and increased the expression of RNA m6A "eraser" FTO in H9c2 cells conventionally cultured and subjected to IR. CSE knockdown counteracted the inhibitory effect of CUR treatment on ROS production, promotion on cell viability, and inhibition on apoptosis of H9c2 cells subjected to IR. CUR attenuates MIRI by regulating the expression of H2S level-regulating enzymes and increasing the endogenous H2S levels. Increased H2S levels could regulate the m6A-related proteins expression and intracellular total RNA m6A levels.

A large-Stokes-shift fluorescence sensor for sensitive detection of iron ions: Rapid monitoring of Fe3+ in water samples, hydroponic fertilizers, and living cells via fluorescence visualization

Iron ions (Fe2+ and Fe3+) are physiologically essential for humans; however, an imbalance in intracellular iron ion levels can cause adverse health effects. Therefore, developing a method for monitoring iron ions in biological and environmental systems is necessary. In this study, a new fluorescence sensor derived from [5]helicene linked to 2‐methylene pyridine (M201P) was successfully synthesized. The sensor could detect iron ions with high sensitivity via fluorescence quenching with a large Stokes shift (175 nm). The total iron ion content in samples was determined via the simple oxidation of Fe2+ to Fe3+ using H2O2. The Fe3+‐sensing performance of the sensor efficiently tolerated interference from other metal ions, and the detection limit was found to be 0.51 μM (0.028 ppm). The sensor formed a complex with Fe3+ with a stoichiometric ratio of 2:1, as measured using a Job’s plot. Its binding mode was further investigated via 1H NMR titration and molecular modeling. In addition, using ultraviolet irradiation, M201P was used to visualize and monitor Fe3+ in water samples, hydroponic fertilizers, and living cells.

8-Cl-Ado and 8-NH2-Ado synergize with venetoclax to target the methionine-MAT2A-SAM axis in acute myeloid leukemia.

Targeting the metabolic dependencies of acute myeloid leukemia (AML) cells is a promising therapeutical strategy. In particular, the cysteine and methionine metabolism pathway (C/M) is significantly altered in AML cells compared to healthy blood cells. Moreover, methionine has been identified as one of the dominant amino acid dependencies of AML cells. Through RNA-seq, we found that the two nucleoside analogs 8-chloro-adenosine (8CA) and 8-amino-adenosine (8AA) significantly suppress the C/M pathway in AML cells, and methionine-adenosyltransferase-2A (MAT2A) is one of most significantly downregulated genes. Additionally, mass spectrometry analysis revealed that Venetoclax (VEN), a BCL-2 inhibitor recently approved by the FDA for AML treatment, significantly decreases the intracellular level of methionine in AML cells. Based on these findings, we hypothesized that combining 8CA or 8AA with VEN can efficiently target the Methionine-MAT2A-S-adenosyl-methionine (SAM) axis in AML. Our results demonstrate that VEN and 8CA/8AA synergistically decrease the SAM biosynthesis and effectively target AML cells both in vivo and in vitro. These findings suggest the promising potential of combining 8CA/8AA and VEN for AML treatment by inhibiting Methionine-MAT2A-SAM axis and provide a strong rationale for our recently activated clinical trial.

Astragaloside-IV promotes autophagy via the Akt/mTOR pathway to improve cellular lipid deposition.

The current study aimed to investigate the potential role of astragaloside IV (AS-IV) in improving cellular lipid deposition and its underlying mechanism. A fatty liver cell model was established by treating hepatoma cells with palmitic acid. AS-IV and SC79 were used for treatment. Oil Red O staining was applied to detect intracellular lipid deposition, and transmission electron microscopy was utilized to assess autophagosome formation. Immunofluorescence double staining was applied to determine microtubule-associated proteins 1A/1B light chain 3 (LC3) expression. Western blot analysis was performed to detect the expression of LC3, prostacyclin, Beclin-1, V-akt murine thymoma viral oncogene homolog (Akt), phosphorylated Akt, mTOR, and phosphorylated mTOR. Oil Red O staining revealed that AS-IV reduced intracellular lipid accumulation. Further, it increased autophagosome synthesis and the expression of autophagy proteins LC3 and Beclin-1 in the cells. It also reduced the phosphorylation levels of Akt and mTOR and the levels of prostacyclin. However, the effects of AS-IV decreased with SC79 treatment. In addition, LC3B + BODIPY493/503 fluorescence double staining showed that AS-IV reduced intracellular lipid deposition levels by enhancing autophagy. AS-IV can reduce lipid aggregation in fatty liver cells, which can be related to enhanced hepatocyte autophagy by inhibiting the Akt/mTOR signaling pathway.

Comparison of the Antioxidant Potency of Four Triterpenes of Centella asiatica against Oxidative Stress.

We comparatively evaluated the antioxidant properties of key triterpenes from Centella asiatica, including asiatic acid (AA), asiaticoside, madecassic acid, and madecassoside, in several cell types, including skin fibroblasts, macrophages, hepatocytes, and endothelial cells, under conditions promoting oxidative stress. AA conferred the highest viability on Hs68 cells exposed to ultraviolet B (UVB) irradiation. Triterpene pretreatment attenuated the UVB-induced generation of reactive oxygen species (ROS) and malondialdehyde (MDA), as well as the UVB-induced depletion of glutathione (GSH) in skin fibroblasts. AA most potently inhibited UVB-induced MMP generation, resulting in increased intracellular collagen levels. Pretreatment with triterpenes, particularly AA, significantly improved cell viability and attenuated TBHP-induced levels of ROS, alanine aminotransferase, and aspartate aminotransferase in HepG2 cells. Triterpenes attenuated ROS levels and reduced MDA and GSH expression in EA.hy926 cells. In RAW264.7 macrophages, production of nitric oxide, tumor necrosis factor-α, and interleukin-6 (indicators of LPS-induced oxidative damage) was significantly reduced by treatment with any of the triterpenes. Statistical analyses of triterpene biological activities using principal component analysis and hierarchical clustering revealed that AA exerted the greatest overall influence and showed remarkable activity in Hs68 and HepG2 cells.

SIRT3 suppression resulting from the enhanced β-catenin signaling drives glycolysis and promotes hypoxia-induced cell growth in hepatocellular carcinoma cells

ABSTRACT The precise mechanisms underlying the inhibitory effects of SIRT3, a mitochondrial sirtuin protein, on hepatocellular carcinoma (HCC) development, as well as its impact on mitochondrial respiration, remain poorly understood. We assessed sirtuins 3 (SIRT3) levels in HCC tissues and Huh7 cells cultured under hypoxic condition. We investigated the effects of SIRT3 on cell proliferation, glycolytic metabolism, mitochondrial respiration, mitophagy, and mitochondrial biogenesis in Huh7 cells. Besides, we explored the potential mechanisms regulating SIRT3 expression in hypoxically cultured Huh7 cells. Gradual reduction in SIRT3 expressions were observed in both adjacent tumor tissues and tumor tissues. Similarly, SIRT3 expressions were diminished in Huh7 cells cultured under hypoxic condition. Forced expression of SIRT3 attenuated the growth of hypoxically cultured Huh7 cells. SIRT3 overexpression led to a decrease in extracellular acidification rate while increasing oxygen consumption rate. SIRT3 downregulated the levels of hexokinase 2 and pyruvate kinase M2. Moreover, SIRT3 enhanced mitophagy signaling, as indicated by mtKeima, and upregulated key proteins involved in various mitophagic pathways while reducing intracellular reactive oxygen species levels. Furthermore, SIRT3 increased proxisome proliferator-activated receptor-gamma coactivator 1α levels and the amount of mitochondrial DNA in Huh7 cells. Notably, β-catenin expressions were elevated in Huh7 cells cultured under hypoxic condition. Antagonists and agonists of β-catenin respectively upregulated and downregulated SIRT3 expressions in hypoxically cultured Huh7 cells. The modulationsof glycolysis and mitochondrial respiration represent the primary mechanism through which SIRT3, suppressed by β-catenin, inhibits HCC cell proliferation.

Analysis of Lemon Verbena Polyphenol Metabolome and Its Correlation with Oxidative Stress under Glucotoxic Conditions in Adipocyte.

Lemon verbena has been shown to ameliorate obesity-related oxidative stress, but the intracellular final effectors underlying its antioxidant activity are still unknown. The purpose of this study was to correlate the antioxidant capacity of plasma metabolites of lemon verbena (verbascoside, isoverbascoside, hydroxytyrosol, caffeic acid, ferulic acid, homoprotocatechuic acid, and luteolin-7-diglucuronide) with their uptake and intracellular metabolism in hypertrophic adipocytes under glucotoxic conditions. To this end, intracellular ROS levels were measured, and the intracellular metabolites were identified and quantified by high-performance liquid chromatography with a diode array detector coupled to mass spectrometry (HPLC-DAD-MS). The results showed that the plasma metabolites of lemon verbena are absorbed by adipocytes and metabolized through phase II reactions and that the intracellular appearance of these metabolites correlates with the decrease in the level of glucotoxicity-induced oxidative stress. It is postulated that the biotransformation and accumulation of these metabolites in adipocytes contribute to the long-term antioxidant activity of the extract.

Corn Silk Polysaccharide Reduces the Risk of Kidney Stone Formation by Reducing Oxidative Stress and Inhibiting COM Crystal Adhesion and Aggregation.

HK-2 cells were damaged by 100 nm COM crystals to build an injury model. The cells were protected by CSPs with -COOH contents of 3.92% (CSP0) and 16.38% (CCSP3), respectively. The changes in the biochemical indexes of HK-2 cells and the difference in adhesion amount and aggregation degree of nano-COM on the cell surface before and after CSP protection were detected. CSP0 and CCSP3 protection can obviously inhibit HK-2 cell damage caused by nano-COM crystals, restore cytoskeleton morphology, reduce intracellular ROS level, inhibit phosphoserine eversion, restore the polarity of the mitochondrial membrane potential, normalize the cell cycle process, and reduce the expression of adhesion molecules, OPN, Annexin A1, HSP90, HAS3, and CD44 on the cell surface. Finally, the adhesion and aggregation of nano-COM crystals on the cell surface were effectively inhibited. The carboxymethylated CSP3 exhibited a higher protective effect on cells than the original CSP0, and cell viability was further improved with the increase in polysaccharide concentration. CSPs can protect HK-2 cells from calcium oxalate crystal damage and effectively reduce the adhesion and aggregation of nano-COM crystals on the cell surface, which is conducive to inhibiting the formation of calcium oxalate kidney stones.

Novel Peptides from Sturgeon Ovarian Protein Hydrolysates Prevent Oxidative Stress-Induced Dysfunction in Osteoblast Cells: Purification, Identification, and Characterization.

This study aimed to explore antioxidant peptides derived from sturgeon (Acipenser schrenckii) ovaries that exhibit antiosteoporotic effects in oxidative-induced MC3T3-E1 cells. The F3-15 component obtained from sturgeon ovarian protein hydrolysates (SOPHs) via gel filtration and RP-HPLC significantly increased the cell survival rate (from 49.38 ± 2.88 to 76.26 ± 2.09%). Two putative antioxidant-acting peptides, FDWDRL (FL6) and FEGPPFKF (FF8), were screened from the F3-15 faction via liquid chromatography-tandem mass spectrometry (LC-MS/MS) and through prediction by computer simulations. Molecular docking results indicated that the possible antioxidant mechanisms of FL6 and FF8 involved blocking the active site of human myeloperoxidase (hMPO). The in vitro tests showed that FL6 and FF8 were equally adept at reducing intracellular ROS levels, increasing the activity of antioxidant enzymes, and protecting cells from oxidative injuries by inhibiting the mitogen-activated protein kinase (MAPK) pathway and activating the phosphoinositide-3 kinase (PI3K)/protein kinase B (AKT)/glycogen synthase kinase-3β (GSK-3β) signaling pathway. Moreover, both peptides could increase differentiation and mineralization abilities in oxidatively damaged MC3T3-E1 cells. Furthermore, FF8 exhibited high resistance to pepsin and trypsin, showcasing potential for practical applications.

Effects of PDE-3 inhibition in persistent post-traumatic headache: evidence of cAMP-dependent signaling

BackgroundPhosphodiesterase 3 (PDE-3) inhibition have been implicated in the neurobiologic underpinnings of migraine. Considering the clinical similarities between migraine and persistent post-traumatic headache (PPTH), we aimed to ascertain whether PDE-3 inhibition can elicit migraine-like headache in persons with PPTH.MethodsWe tested cilostazol, which inhibits PDE-3, in a randomized, double-blind, placebo-controlled, two-way crossover study involving persons with PPTH attributed to mild traumatic brain injury. The randomized participants were allocated to receive oral administration of either 200-mg cilostazol or placebo (calcium tablet) on two separate experiment days. The primary end point was the incidence of migraine-like headache during a 12-hour observation window post-ingestion. The secondary endpoint was the area under the curve (AUC) for reported headache intensity scores during the same observation window.ResultsTwenty-one persons underwent randomization and completed both experiment days. The mean participants’ age was 41.4 years, and most (n = 17) were females. During the 12-hour observation window, 14 (67%) of 21 participants developed migraine-like headache post-cilostazol, in contrast to three (14%) participants after placebo (P =.003). The headache intensity scores were higher post-cilostazol than after placebo (P <.001).ConclusionsOur results provide novel evidence showing that PDE-3 inhibition can elicit migraine-like headache in persons with PPTH. Given that PDE-3 inhibition increases intracellular cAMP levels, our findings allude to the potential therapeutic value of targeting cAMP-dependent signaling pathways in the management of PPTH. Further investigations are imperative to substantiate these insights and delineate the importance of cAMP-dependent signaling pathways in the neurobiologic mechanisms underlying PPTH.ClinicalTrials.gov IdentifierNCT05595993.

Benzo[a]pyrene exposure causes exonal switch resulting in reduced surface CD5 expression in an AHR-dependent manner

The function of CD5 protein in T cells is well documented, but regulation of its surface-level expression has yet to be fully understood. However, variation in its surface expression is associated with various immunopathological conditions and haematological malignancies. Briefly, expression of an alternate exon E1B of a human endogenous retroviruses (HERV) origin directly downregulates the conventional transcript variant (E1A), as its expression leads to the retention of the resultant protein at the intracellular level (cCD5). A separate promoter governs the expression of E1B and may be influenced by different transcription factors. Hence, we performed in silico transcription factor binding site (TFBS) analysis of the 3 kb upstream region from TSS of exon E1B and found five putative DREs (Dioxin Response elements) with good similarity scores. Further, we observed the upregulation in E1B expression after the exposure of BaP (a dioxin) and the reduction of E1A expression and their respective protein, i.e. sCD5 and cCD5. The binding of AHR at the predicted DRE sites was confirmed by ChIP qPCR and AHR specific inhibitor and gene silencing studies suggested the involvement of AHR in exonal switch. This study indicates that the polycyclic aromatic hydrocarbon decreases the sCD5 expression by upregulating alternative exon expression, which may adversely affect the overall T cell functions.

Critical role of G3BP1 in bovine parainfluenza virus type 3 (BPIV3)-inhibition of stress granules formation and viral replication.

It remains unclear whether BPIV3 infection leads to stress granules formation and whether G3BP1 plays a role in this process and in viral replication. This study aims to clarify the association between BPIV3 and stress granules, explore the effect of G3BP1 on BPIV3 replication, and provide significant insights into the mechanisms by which BPIV3 evades the host's antiviral immunity to support its own survival. Here, we use Immunofluorescence staining to observe the effect of BPIV3 infection on the assembly of stress granules. Meanwhile, the expression changes of eIF2α and G3BP1 were determined. Overexpression or siRNA silencing of intracellular G3BP1 levels was examined for its regulatory control of BPIV3 replication. We identify that the BPIV3 infection elicited phosphorylation of the eIF2α protein. However, it did not induce the assembly of stress granules; rather, it inhibited the formation of stress granules and downregulated the expression of G3BP1. G3BP1 overexpression facilitated the formation of stress granules within cells and hindered viral replication, while G3BP1 knockdown enhanced BPIV3 expression. This study suggest that G3BP1 plays a crucial role in BPIV3 suppressing stress granule formation and viral replication.

Glutathione Depletion and Stalwart Anticancer Activity of Metallotherapeutics Inducing Programmed Cell Death: Opening a New Window for Cancer Therapy.

The cellular defense system against exogenous substances makes therapeutics inefficient as intracellular glutathione (GSH) exhibits an astounding antioxidant activity in scavenging reactive oxygen species (ROS) or reactive nitrogen species (RNS) or other free radicals produced by the therapeutics. In the cancer cell microenvironment, the intracellular GSH level becomes exceptionally high to fight against oxidative stress created by the production of ROS/RNS or any free radicals, which are the byproducts of intracellular redox reactions or cellular respiration processes. Thus, in order to maintain redox homeostasis for survival of cancer cells and their rapid proliferation, the GSH level starts to escalate. In this circumstance, the administration of anticancer therapeutics is in vain, as the elevated GSH level reduces their potential by reduction or by scavenging the ROS/RNS they produce. Therefore, in order to augment the therapeutic potential of anticancer agents against elevated GSH condition, the GSH level must be depleted by hook or by crook. Hence, this Review aims to compile precisely the role of GSH in cancer cells, the importance of its depletion for cancer therapy and examples of anticancer activity of a few selected metal complexes which are able to trigger cancer cell death by depleting the GSH level.

Respiratory Responses to Single Oral Administration of Taurine in Sprague-Dawley Rats.

Taurine is a nonessential amino acid that has been increasingly consumed due to its various beneficial biological effects. Excessive taurine intake has been linked to the positive regulation of inflammatory responses and endoplasmic reticulum stress through the modulation of intracellular calcium levels. However, research on the potential adverse effects of taurine consumption on the respiratory system is limited. To address this, we investigated the respiratory responses of 6-week-old male Sprague-Dawley rats to taurine administered orally at 0, 100, 200, and 400 mg/kg. Respiratory rate, tidal volume, and minute volume were monitored in accordance with the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) Harmonized Tripartite Guideline S7A for Safety Pharmacology Studies for Human Pharmaceuticals. We found that taurine administration did not significantly alter respiratory rate or tidal volume; however, a significant increase in minute volume was observed 6 h after administration of 200 mg/kg taurine.