Expression Levels Of Transporters Research Articles

Impact of dietary fat types on expression levels of dopamine and serotonin transporters in the ileum of broiler chickens

Impact of dietary fat types on expression levels of dopamine and serotonin transporters in the ileum of broiler chickens

CE9A215 (inotodiol), a lanostane-type oxysterol, mitigates LPS-induced sepsis through multifaceted mechanisms

Dysregulated host response against infection triggers sepsis that leads to multiple organ dysfunction due to uncontrolled inflammatory responses. Despite marked progress in understanding of sepsis, numerous clinical trials for treatment of sepsis have proven daunting and a new therapeutic approach is highly needed. CE9A215 (inotodiol), a fungal secondary metabolite, has been researched for its pharmacological activities and has shown potent anti-allergic effects. In this study, we evaluated the anti-inflammatory activities of CE9A215 upon lipopolysaccharide (LPS) stimulation in vivo and in vitro for the first time. CE9A215 decreased the production of interleukin (IL)-6, tumor necrosis factor alpha (TNF-α), and IL-1β in a concentration-dependent manner in LPS-stimulated RAW264.7 cells. Intriguingly, in human mast cell line LUVA, CE9A215 significantly lowered IL-4 and IL-10, and this effect could be beneficial for the clearance of bacterial infection. In addition, administration of CE9A215 improved the survival rate of LPS-stimulated mice and inhibited the pro-inflammatory cytokines, IL-6, TNF-α, and IL-1β in blood. Moreover, CE9A215 enhanced the expression levels of plasma phospholipid transfer protein (PLTP), apolipoprotein E (ApoE), and ATP-binding cassette transporter (ABCA1) in LPS-stimulated RAW246.7 cells. Liver PLTP level increased significantly in the CE9A215-administered group compared with the control group, which implies that CE9A215 promotes LPS clearance and neutralization by reverse transport of LPS by increasing the expressions of PLTP, ApoE, and ABCA1. Our results highlight CE9A215’s potential as a novel therapeutic option for the treatment of sepsis.

Reprogramming of Glutamine Amino Acid Transporters Expression and Prognostic Significance in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is the most prevalent primary liver malignancy and is a major cause of cancer-related mortality in the world. This study aimed to characterize glutamine amino acid transporter expression profiles in HCC compared to those of normal liver cells. In vitro and in vivo models of HCC were studied using qPCR, whereas the prognostic significance of glutamine transporter expression levels within patient tumors was analyzed through RNAseq. Solute carrier (SLC) 1A5 and SLC38A2 were targeted through siRNA or gamma-p-nitroanilide (GPNA). HCC cells depended on exogenous glutamine for optimal survival and growth. Murine HCC cells showed superior glutamine uptake rate than normal hepatocytes (p < 0.0001). HCC manifested a global reprogramming of glutamine transporters compared to normal liver: SLC38A3 levels decreased, whereas SLC38A1, SLC7A6, and SLC1A5 levels increased. Also, decreased SLC6A14 and SLC38A3 levels or increased SLC38A1, SLC7A6, and SLC1A5 levels predicted worse survival outcomes (all p < 0.05). Knockdown of SLC1A5 and/or SLC38A2 expression in human Huh7 and Hep3B HCC cells, as well as GPNA-mediated inhibition, significantly decreased the uptake of glutamine; combined SLC1A5 and SLC38A2 targeting had the most considerable impact (all p < 0.05). This study revealed glutamine transporter reprogramming as a novel hallmark of HCC and that such expression profiles are clinically significant.

Differential Mitochondrial Adaptation of the Slow and Fast Skeletal Muscles by Endurance Running Exercise in Streptozotocin-Induced Diabetic Mice.

The skeletal muscle is the main organ responsible for insulin action, and glucose disposal and metabolism. Endurance and/or resistance training raises the number of mitochondria in diabetic muscles. The details of these adaptations, including mitochondrial adaptations of the slow and fast muscles in diabetes, are unclear. This study aimed to determine whether exercise training in streptozotocin (STZ)-induced mice leads to differential adaptations in the slow and fast muscles, and improving glucose clearance. Eight-week-old mice were randomly distributed into normal control (CON), diabetes (DM), and diabetes and exercise (DM+Ex) groups. In the DM and DM+Ex groups, mice received a freshly prepared STZ (100 mg/kg) intraperitoneal injection on two consecutive days. Two weeks after the injection, the mice in the groups ran on a treadmill for 60 min at 20 m/min for a week and subsequently at 25 m/min for 5 weeks (5 days/week). The analyses indicated that running training at low speed (25 m/min) enhanced mitochondrial enzyme activity and expression of lactate and glucose transporters in the plantaris (low-oxidative) muscle that improved whole-body glucose metabolism in STZ-induced diabetic mice. There were no differences in glucose transporter expression levels in the soleus (high-oxidative) muscle. The endurance running exercise at 20-25 m/min was sufficient to induce mitochondrial adaptation in the low-oxidative muscles, but not in the high-oxidative muscles, of diabetic mice. In conclusion, the present study indicated that running training at 25 m/min improved glucose metabolism by increasing the mitochondrial enzyme activity and glucose transporter 4 and monocarboxylate transporter 4 protein contents in the low-oxidative muscles in STZ-induced diabetic mice.

Ameliorative action of "daitongxiao" against hyperuricemia includes the "uric acid transporter group".

This study aimed to investigate the potential mechanisms involved in the therapeutic effects of daitongxiao (DTX) on hyperuricemia (HUA). DTX was administered to two animal models of HUA via gavage feeding: HUA quail model (a uricotelic animal with urate oxidase deficiency), treated continuously for 35 days post-HUA induction, and HUA rats (an animal with active urate oxidase), treated continuously for 28days post-HUA induction. HUA was induced in quail by administering a solution of sterile dry yeast powder via gavage feeding, while in rats, it was induced by intragastric gavage feeding of a solution of adenine and ethambutol hydrochloride. DTX improved overall health; increased bodyweight; reduced renal index, serum urate levels, serum xanthine oxidase activity, blood urea nitrogen, and creatinine; and enhanced urinary and fecal uric acid (UA) excretion in these two animal models. The results of hematoxylin and eosin and hexamine silver staining of kidney sections revealed that DTX significantly mitigated HUA-induced renal structural damage and inflammatory response. The results of quantitative real-time polymerase chain reaction, Western blotting, and immunofluorescence analyses revealed that DTX downregulated the renal expression levels of glucose transporter 9 (GLUT9) and upregulated the renal expression levels of organic anion transporters (OAT1 and OAT3) in both HUA models. Thus, the findings of this study suggest that DTX suppresses the progression of HUA by modulating the expression of the UA transporter group members.

Protective effect of Albizia chinensis saponin on ethanol-induced gastric mucosal injury in rats focus on mucus and mucosal barriers

This study aims to explore the protective effect of Albizia chinensis saponin on ethanol-induced acute gastric ulcer in rats and elucidate its mechanisms. SD rats were deprived of water for 24 hours before the experiment. The control group and model group were administered water by gavage, and the positive drug group received rabeprazole sodium solution(40 mg·kg~(-1)) by gavage. The experimental groups were given different doses of Albizia chinensis saponin solution(3, 10, and 30 mg·kg~(-1)). After 30 minutes, the control group received 1.5 mL of water by gavage, while the other groups were administered an equal volume of 95% ethanol for modeling. After six hours, the rats were killed by cervical dislocation, and the stomachs were collected. The ulcer area was measured, and the ulcer index was calculated. Hematoxylin-eosin(HE) staining was performed to assess histopathological changes in gastric tissue. Periodic acid-Schiff(PAS) staining was used to evaluate the distribution of gastric mucosal surface mucus. Enzyme-linked immunosorbent assay(ELISA) was employed to measure the levels of phospholipids and aminohexose in the gastric mucosa. Western blot was performed to determine the expression levels of the bicarbonate transporter, matrix metalloproteinase, and tight junction-associated proteins in gastric tissue. Immunohistochemistry(IHC) staining was conducted to quantify the number of positive cells for secreted mucin and tight junction-associated proteins. The results showed that the gastric tissue surface of rats in the control group was smooth without ulceration, and the gastric ulcer index of rats in the model group was 35±11. Albizia chinensis saponin at doses of 3, 10, and 30 mg·kg~(-1) resulted in inhibition rates of gastric ulcer of 46%(P&lt;0.01), 85%(P&lt;0.001), and 100%(P&lt;0.001), respectively. Severe disruption of gastric mucosal structure and absence of the mucus layer were observed in the model group. Compared with the model group, the Albizia chinensis saponin group showed intact gastric mucosal surface mucus layer, significantly increased levels of phospholipids and aminohexose in the mucus, increased number of MUC5AC positive cells, and upregulated expression levels of the bicarbonate transporter SLC26A3 and CFTR. It also showed decreased phosphorylation of JNK and c-Jun, reduced expression levels of MMP-8, elevated expression of TIMP-1, and increased expression levels of Occludin and ZO-1. In conclusion, Albizia chinensis saponin enhances the function of the mucus-bicarbonate barrier by upregulating the content of MUC5AC, phospholipids, and aminohexose and increasing the expression levels of the bicarbonate transporter SLC26A3 and CFTR. Moreover, Albizia chinensis saponin exerts its protective effects on gastric ulcers by inhibiting the JNK signaling pathway to prevent excessive activation of MMP-8, thereby reducing the degradation of Occludin and ZO-1 and enhancing the mucosal barrier function. In summary, Albizia chinensis saponin exerts its anti-gastric ulcer effects by simultaneously enhancing the mucus barrier and the mucosal barrier.

Gypenoside XVII Reduces Synaptic Glutamate Release and Protects against Excitotoxic Injury in Rats.

Excitotoxicity is a common pathological process in neurological diseases caused by excess glutamate. The purpose of this study was to evaluate the effect of gypenoside XVII (GP-17), a gypenoside monomer, on the glutamatergic system. In vitro, in rat cortical nerve terminals (synaptosomes), GP-17 dose-dependently decreased glutamate release with an IC50 value of 16 μM. The removal of extracellular Ca2+ or blockade of N-and P/Q-type Ca2+ channels and protein kinase A (PKA) abolished the inhibitory effect of GP-17 on glutamate release from cortical synaptosomes. GP-17 also significantly reduced the phosphorylation of PKA, SNAP-25, and synapsin I in cortical synaptosomes. In an in vivo rat model of glutamate excitotoxicity induced by kainic acid (KA), GP-17 pretreatment significantly prevented seizures and rescued neuronal cell injury and glutamate elevation in the cortex. GP-17 pretreatment decreased the expression levels of sodium-coupled neutral amino acid transporter 1, glutamate synthesis enzyme glutaminase and vesicular glutamate transporter 1 but increased the expression level of glutamate metabolism enzyme glutamate dehydrogenase in the cortex of KA-treated rats. In addition, the KA-induced alterations in the N-methyl-D-aspartate receptor subunits GluN2A and GluN2B in the cortex were prevented by GP-17 pretreatment. GP-17 also prevented the KA-induced decrease in cerebral blood flow and arginase II expression. These results suggest that (i) GP-17, through the suppression of N- and P/Q-type Ca2+ channels and consequent PKA-mediated SNAP-25 and synapsin I phosphorylation, reduces glutamate exocytosis from cortical synaptosomes; and (ii) GP-17 has a neuroprotective effect on KA-induced glutamate excitotoxicity in rats through regulating synaptic glutamate release and cerebral blood flow.

Mechanisms of Sorafenib Resistance in HCC Culture Relate to the Impaired Membrane Expression of Organic Cation Transporter 1 (OCT1).

Sorafenib, an FDA-approved drug for advanced hepatocellular carcinoma (HCC) treatment, encounters resistance in many patients. Deciphering the mechanisms underlying sorafenib resistance is crucial for devising alternative strategies to overcome it. This study aimed to investigate sorafenib resistance mechanisms using a diverse panel of HCC cell lines. HCC cell lines were subjected to continuous sorafenib treatment, and stable cell lines (Huh 7.5 and Huh 7PX) exhibiting sustained growth in its presence were isolated. The investigation of drug resistance mechanisms involved a comparative analysis of drug-targeted signal transduction pathways (EGFR/RAF/MEK/ERK/Cyclin D), sorafenib uptake, and membrane expression of the drug uptake transporter. HCC cell lines (Huh 7.5 and Huh 7PX) with a higher IC50 (10μM) displayed a more frequent development of sorafenib resistance compared to those with a lower IC50 (2-4.8μM), indicating a potential impact of IC50 variation on initial treatment response. Our findings reveal that activated overexpression of Raf1 kinases and impaired sorafenib uptake, mediated by reduced membrane expression of organic cation transporter-1 (OCT1), contribute to sorafenib resistance in HCC cultures. Stable expression of the drug transporter OCT1 through cDNA transfection or adenoviral delivery of OCT1 mRNA increased sorafenib uptake and successfully overcame sorafenib resistance. Additionally, consistent with sorafenib resistance in HCC cultures, cirrhotic liver-associated human HCC tumors often exhibited impaired membrane expression of OCT1 and OCT3. Intrinsic differences among HCC cell clones, affecting sorafenib sensitivity at the expression level of Raf kinases, drug uptake, and OCT1 transporters, were identified. This study underscores the potential of HCC tumor targeted OCT1 expression to enhance sorafenib treatment response.

Abstract 2050: Slc43a3 And Intracellular Fatty Acid Trafficking

Background: Fatty acids (FAs) have important roles in many cellular functions. Dysregulation of FA flux is both a characteristic and effector of many prevalent clinical conditions, including diabetes mellitus, obesity as well as insulin resistance and/or metabolic syndrome. Adipocytes take up long chain fatty acids through diffusion and protein mediated transport, whereas fatty acid efflux is considered to occur by diffusion. Our previous study suggests the possibility of a protein facilitated/regulated process of FA efflux by demonstrating that the organic anion transport inhibitor DIDS strongly inhibits FA efflux in lipolytically-stimulated adipocytes, leading to an accumulation of intracellular FAs, while not affecting glycerol efflux. We hypothesize that there is potential regulator(s) for FA efflux. Methods and Results: In a screen of subcutaneous adipose samples from obese patients for expression levels of transporters without known function, Slc43a3 (a member of the solute carrier transporter family) shown increased expression after bariatric surgery. In addition, Slc43a3 regulates fatty acid flux in adipocytes. To study the mechanism of Slc43a3 function, clonal lines of preadipocyte OP9 cells were generated, in which green fluorescent protein has been knocked-in at the C-terminus of endogenous Slc43a3 using CRISPR/Cas9. In parallel, Slc43a3 knockout (KO) line has also been generated. Examination of the cells showed that expression of Slc43a3 induced in the cytoplasm of the adipocytes during differentiation. Slc43a3KO adipocytes accumulate bigger lipid droplets and less small lipid droplets. To study the functional significance of Slc43a3 in vivo, adipose tissue specific KO of Slc43a3 were generated with floxed Slc43a3 and tamoxifen induced adiponectin-Cre recombinase. The Slc43a3 KO mice have less body weight and less % body fat on a normal chow diet; however, no differences are noted when the mice are switched to high fat diet, indicating the lack of lipid signaling molecules in the Slc43a3 KO mice with normal chow diet. Functional analysis shows a blunted stimulated lipolysis in the Slc43a3 KO mice. Conclusions: Both in vitro and in vivo data confirmed an unique role of Slc43a3 in regulating fatty acid flux in adipose tissue.

Investigation of morpho-physiolgical traits and gene expression in barley under nitrogen deficiency

Nitrogen (N) is an essential element for plant growth, and its deficiency influences plants at several physiological and gene expression levels. Barley (Hordeum vulgare) is one of the most important food grains from the Poaceae family and one of the most important staple food crops. However, the seed yield is limited by a number of stresses, the most important of which is the insufficient use of N. Thus, there is a need to develop N-use effective cultivars. In this study, comparative physiological and molecular analyses were performed using leaf and root tissues from 10 locally grown barley cultivars. The expression levels of nitrate transporters, HvNRT2 genes, were analyzed in the leaf and root tissues of N-deficient (ND) treatments of barley cultivars after 7 and 14 days following ND treatment as compared to the normal condition. Based on the correlation between the traits, root length (RL) had a positive and highly significant correlation with fresh leaf weight (FLW) and ascorbate peroxidase (APX) concentration in roots, indicating a direct root and leaf relationship with the plant development under ND. From the physiological aspects, ND enhanced carotenoids, chlorophylls a/b (Chla/b), total chlorophyll (TCH), leaf antioxidant enzymes such as ascorbate peroxidase (APX), peroxidase (POD), and catalase (CAT), and root antioxidant enzymes (APX and POD) in the Sahra cultivar. The expression levels of HvNRT2.1, HvNRT2.2, and HvNRT2.4 genes were up-regulated under ND conditions. For the morphological traits, ND maintained root dry weight among the cultivars, except for Sahra. Among the studied cultivars, Sahra responded well to ND stress, making it a suitable candidate for barely improvement programs. These findings may help to better understand the mechanism of ND tolerance and thus lead to the development of cultivars with improved nitrogen use efficiency (NUE) in barley.

Herb–drug interactions: Quantitative analysis of levofloxacin absorption and transporter expression in the rat intestine following combined treatment with Persicaria capitata (Buch.-Ham. ex D. Don) H. Gross

Persicaria capitata (Buch.-Ham. ex D. Don) H. Gross, a traditional Chinese medicinal plant, is often used to treat various urologic disorders in China. P. capitata extracts (PCE) have been used in combination with levofloxacin (LVFX) to treat urinary tract infections (UTIs) for a long time. However, little is known about the absorption of LVFX and transporter expression in the intestine after combined treatment with PCE, restricting the development and utilization of PCE. In view of this, a UPLC-MS/MS method was established for the determination of LVFX in intestinal sac fluid samples and in situ intestinal circulation perfusate samples to explore the effect of PCE on the intestinal absorption characteristics of LVFX ex vivo and in vivo. To further evaluate the interaction between LVFX and PCE, western blotting, immunohistochemistry, and RT-qPCR were utilized to determine the expression levels of drug transporters (OATP1A2, P-gp, BCRP, and MRP2) involved in the intestinal absorption of LVFX after combined treatment with PCE. Using the everted intestinal sac model, the absorption rate constant (Ka) and cumulative drug absorption (Q) of LVFX in each intestinal segment were significantly lower in groups treated with PCE than in the control group. Ka at 2 h decreased most in the colon segment (from 0.088 to 0.016 µg/h·cm2), and Q at 2 h decreased most in the duodenum (from 213.29 to 33.92 µg). Using the intestinal circulation perfusion model, the Ka value and percentage absorption rate (A) of LVFX in the small intestine decreased significantly when PCE and LVFX were used in combination. These results showed that PCE had a strong inhibitory effect on the absorption of LVFX in the rat small intestine (ex vivo and in vivo intestinal segments). In addition, PCE increased the protein and mRNA expression levels of efflux transporters (P-gp, BCRP, and MRP2) and decreased the expression of the uptake transporter OATP1A2 significantly. The effects increased as the PCE concentration increased. These findings indicated that PCE changed the absorption characteristics of levofloxacin, possibly by affecting the expression of transporters in the small intestine. In addition to revealing a herb–drug interaction (HDI) between PCE and LVFX, these results provide a basis for further studies of their clinical efficacy and mechanism of action.

Abstract 6850: Unraveling molecular factors contributing to metallomic dyshomeostasis induced by triple-negative breast cancer using single-cell RNA sequencing

Abstract Triple-negative breast cancer (TNBC) comprises 20% of breast cancer cases and exhibits an aggressive phenotype with increased metastasis; these patients have limited treatment options, poorer prognosis and higher mortality than other breast cancers (BC). Metallomics is a relatively new discipline that studies the abundance of metal ions in biological samples. Metallomic analysis has identified differences in BC patients in elements such as iron (Fe) and zinc (Zn) but it is unclear if these reflect metabolic changes in the tumor. In this study, we conducted metallomic profiling to characterize 55 trace elements in the circulation and in the tumor microenvironment of orthotopic mammary fat pad tumors from two isogenic BC cell lines (highly metastatic 4T1; nonmetastatic 67NR). We complemented this analysis with single-cell RNA sequencing of the tumor to determine if complementary changes occur in molecules known to utilize metals as co-factors or transporters and identify drivers of metal metabolism in different tumors. We performed analysis on systemic metal elements by examining whole blood (including blood cells and platelets) and plasma separately. Tumor samples were assessed at the whole tissue level, and we also profiled separated immune or non-immune cells from the tumor. Li, Na, Mg, P, S, K, Ca, Fe, Cu, Zn, Rb were detectable within 100ul of input of whole blood or plasma. Metallomic analysis of the tumor and associated cell populations detected differential levels of Na, Mg, P, S, K Ca, Fe, Zn, and Rb from an average of 200mg of tissue or 2 million cells. Based on scRNAseq analysis, 67NR tumors were composed of greater proportions of cancer cells relative to the 4T1 tumors (79.1% vs 58.8% of tumor cells respectively) and endothelial cells (2.5% vs 1.8%). 4T1 tumors contained an increased abundance of cancer-associated fibroblasts (5.6% vs 2.1%) as well as immune infiltration (33.8% vs 16.3%). Fibroblasts and macrophage populations also showed elevated metal transporter expression levels based on gene expression relative to other tumor residing cell types yet minor differences induced by cancer type. Cancer cells express high levels of metal transport genes (Zn, Ca, Co, Na, Mg, Fe). 67NR cancer cells exhibited increased gene expression of many metal-transporting proteins including numerous solute carrier (SLC) group of membrane transport proteins such as Slc41a2 when compared to the more aggressive 4T1 cells. This study underscores the potential of linking metallomic profiling to tumor composition and cancer behaviors, offering a pathway for identifying novel biomarkers to differentiate aggressive and non-aggressive forms of breast cancer. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. Citation Format: Nicholas R. Hum, John M. Rolison, Nicole F. Leon, Ali Navid, Aimy Sebastian, Josh Wimpenny, Gabriela Loots. Unraveling molecular factors contributing to metallomic dyshomeostasis induced by triple-negative breast cancer using single-cell RNA sequencing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6850.

Effect of estrogen and progesterone on intracellular free zinc and zinc transporter expression in bovine oviduct epithelial cells

Zinc (Zn) plays essential roles in numerous cellular processes. However, there is limited understanding of Zn homeostasis within the bovine reproductive system. This study investigated the influence of estradiol (E2) and progesterone (P4) on Zn transporter expression and intracellular free Zn levels in bovine oviduct epithelial cells (BOEC). For this purpose, cells were harvested from slaughtered cows and cultured in vitro. Intracellular Zn concentrations were measured using FluoZin-3AM staining, while real-time polymerase chain reaction assessed Zn transporter gene expression and quantification. Overall, our results confirmed the gene expression of all the evaluated Zn transporters (ZIP6, ZIP8, ZIP14, ZnT3, ZnT7 and ZnT9), denoted and the active role of E2 and P4 in intracellular Zn regulation. Our findings suggest an interaction between Zn, E2 and P4.

Silicon and iron nanoparticles protect rice against lead (Pb) stress by improving oxidative tolerance and minimizing Pb uptake

Lead (Pb) is toxic to the development and growth of rice plants. Nanoparticles (NPs) have been considered one of the efficient remediation techniques to mitigate Pb stress in plants. Therefore, a study was carried out to examine the underlying mechanism of iron (Fe) and silicon (Si) nanoparticle-induced Pb toxicity alleviation in rice seedlings. Si–NPs (2.5 mM) and Fe-NPs (25 mg L−1) were applied alone and in combination to rice plants grown without (control; no Pb stress) and with (100 µM) Pb concentration. Our results revealed that Pb toxicity severely affected all rice growth-related traits, such as inhibited root fresh weight (42%), shoot length (24%), and chlorophyll b contents (26%). Moreover, a substantial amount of Pb was translocated to the above-ground parts of plants, which caused a disturbance in the antioxidative enzyme activities. However, the synergetic use of Fe- and Si–NPs reduced the Pb contents in the upper part of plants by 27%. It reduced the lethal impact of Pb on roots and shoots growth parameters by increasing shoot length (40%), shoot fresh weight (48%), and roots fresh weight (31%). Both Si and Fe–NPs synergistic application significantly elevated superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and glutathione (GSH) concentrations by 114%, 186%, 135%, and 151%, respectively, compared to plants subjected to Pb stress alone. The toxicity of Pb resulted in several cellular abnormalities and altered the expression levels of metal transporters and antioxidant genes. We conclude that the synergistic application of Si and Fe-NPs can be deemed favorable, environmentally promising, and cost-effective for reducing Pb deadliness in rice crops and reclaiming Pb-polluted soils.

Evaluation of the theranostic potential of [64Cu]CuCl2 in glioblastoma spheroids

BackgroundGlioblastoma is an extremely aggressive malignant tumor with a very poor prognosis. Due to the increased proliferation rate of glioblastoma, there is the development of hypoxic regions, characterized by an increased concentration of copper (Cu). Considering this, 64Cu has attracted attention as a possible theranostic radionuclide for glioblastoma. In particular, [64Cu]CuCl2 accumulates in glioblastoma, being considered a suitable agent for positron emission tomography. Here, we explore further the theranostic potential of [64Cu]CuCl2, by studying its therapeutic effects in advanced three-dimensional glioblastoma cellular models. First, we established spheroids from three glioblastoma (T98G, U373, and U87) and a non-tumoral astrocytic cell line. Then, we evaluated the therapeutic responses of spheroids to [64Cu]CuCl2 exposure by analyzing spheroids' growth, viability, and cells' proliferative capacity. Afterward, we studied possible mechanisms responsible for the therapeutic outcomes, including the uptake of 64Cu, the expression levels of a copper transporter (CTR1), the presence of a cancer stem cell population, and the production of reactive oxygen species (ROS).ResultsResults revealed that [64Cu]CuCl2 is able to significantly reduce spheroids' growth and viability, while also affecting cells' proliferation capacity. The uptake of 64Cu, the presence of cancer stem-like cells and the production of ROS were in accordance with the therapeutic response. However, expression levels of CTR1 were not in agreement with uptake levels, revealing that other mechanisms could be involved in the uptake of 64Cu.ConclusionsOverall, our results further support [64Cu]CuCl2 potential as a theranostic agent for glioblastoma, unveiling potential mechanisms that could be involved in the therapeutic response.

The ectomycorrhizal fungus Paxillus ammoniavirescens influences the effects of salinity on loblolly pine in response to potassium availability.

Salinity is an increasing problem in coastal areas affected by saltwater intrusion, with deleterious effects on tree health and forest growth. Ectomycorrhizal (ECM) fungi may improve the salinity tolerance of host trees, but the impact of external potassium (K+ ) availability on these effects is still unclear. Here, we performed several experiments with the ECM fungus Paxillus ammoniavirescens and loblolly pine (Pinus taeda L.) in axenic and symbiotic conditions at limited or sufficient K+ and increasing sodium (Na+ ) concentrations. Growth rate, biomass, nutrient content, and K+ transporter expression levels were recorded for the fungus, and the colonization rate, root development parameters, biomass, and shoot nutrient accumulation were determined for mycorrhizal and non-mycorrhizal plants. P. ammoniavirescens was tolerant to high salinity, although growth and nutrient concentrations varied with K+ availability and increasing Na+ exposure. While loblolly pine root growth and development decreased with increasing salinity, ECM colonization was unaffected by pine response to salinity. The mycorrhizal influence on loblolly pine salinity response was strongly dependent on external K+ availability. This study reveals that P. ammoniavirescens can reduce Na+ accumulation of salt-exposed loblolly pine, but this effect depends on external K+ availability.

Morphological changes in perisynaptic astrocytes induced by dopamine neuronal degeneration in the striatum of rats

IntroductionThe typical functionality of astrocytes was previously shown to be disrupted by Parkinson's disease (PD), which actively regulates synaptic neurotransmission. However, the morphological changes in astrocytes wrapping glutamatergic synapses in the striatum after dopamine (DA) neuronal degeneration is unclear. MethodsWe utilized a range of methodologies, encompassing the 6-hydroxydopamine (6OHDA)-induced PD model, as well as techniques such as immunohistochemistry, Western blotting, immunofluorescence and immunoelectron microscopy (IEM) to delve into the consequences of DA neuronal degeneration on the morphological attributes of perisynaptic astrocytes. ResultsOur findings demonstrated a notable rise in glial fibrillary acidic protein (GFAP) + astrocyte density and an upregulation in GFAP protein expression within the striatum due to DA neuronal degeneration, coincided with the enlargement, elongation, and thickening of astrocyte protuberances. However, the expression levels of glutamate transporter 1 (GLT1) and glutamine synthetase (GS), which are related to glutamate–glutamine cycle, were significantly reduced. Double immunofluorescence and IEM results indicated that different proportions of vesicular glutamate transporter 1 (VGlut1)+ and vesicular glutamate transporter 2 (VGlut2) + terminals were wrapped by astrocytes. Additionally, DA neuronal degeneration increased the percentage and area of VGlut1+ and VGlut2+ terminals wrapped by GFAP + astrocytes in the striatum. Furthermore, we noted that DA neuronal degeneration increased the percentage of VGlut1+ and VGlut2+ axo-spinous synapses wrapped by astrocytes but had no effect on axo-dendritic synapses. ConclusionHence, perisynaptic astrocytes wrapping striatal glutamatergic synapses exhibit substantial morphological and functional alterations following DA neuronal degeneration making them a potential target for therapeutic interventions in PD.

A Small-Molecule Ratiometric Photoacoustic Probe for the High-Spatiotemporal-Resolution Imaging of Copper(II) Dynamics in the Mouse Brain.

Copper dysmetabolism is associated with various neurodegenerative disorders, making high-spatiotemporal-resolution imaging of Cu2+ in the brain essential for understanding the underlying pathophysiological processes. Nevertheless, the current probes encounter obstacles in crossing the blood-brain barrier (BBB) and providing high-spatial-resolution in deep tissues. Herein, we present a photoacoustic probe capable of imaging Cu2+ dynamics in the mouse brain with high-spatiotemporal-resolution. The probe demonstrates selective ratiometric and reversible responses to Cu2+ , while also efficiently crossing the BBB. Using the probe as the imaging agent, we successfully visualized Cu2+ in the brain of Parkinson's disease (PD) model mouse with a remarkable micron-level resolution. The imaging results revealed a significant increase in Cu2+ levels in the cerebral cortex as PD progresses, highlighting the close association between Cu2+ alternations in the region and the disease. We also demonstrated that the probe can be used to monitor changes in Cu2+ distribution in the PD model mouse brain during L-dopa intervention. Mechanism studies suggest that the copper dyshomeostasis in the PD mouse brain was dominated by the expression levels of divalent metal transporter 1. The application of our probe in imaging Cu2+ dynamics in the mouse brain offers valuable insights into the copper-related molecular mechanisms underlying neurodegenerative diseases.

A Small‐Molecule Ratiometric Photoacoustic Probe for the High‐Spatiotemporal‐Resolution Imaging of Copper(II) Dynamics in the Mouse Brain

AbstractCopper dysmetabolism is associated with various neurodegenerative disorders, making high‐spatiotemporal‐resolution imaging of Cu2+ in the brain essential for understanding the underlying pathophysiological processes. Nevertheless, the current probes encounter obstacles in crossing the blood–brain barrier (BBB) and providing high‐spatial‐resolution in deep tissues. Herein, we present a photoacoustic probe capable of imaging Cu2+ dynamics in the mouse brain with high‐spatiotemporal‐resolution. The probe demonstrates selective ratiometric and reversible responses to Cu2+, while also efficiently crossing the BBB. Using the probe as the imaging agent, we successfully visualized Cu2+ in the brain of Parkinson's disease (PD) model mouse with a remarkable micron‐level resolution. The imaging results revealed a significant increase in Cu2+ levels in the cerebral cortex as PD progresses, highlighting the close association between Cu2+ alternations in the region and the disease. We also demonstrated that the probe can be used to monitor changes in Cu2+ distribution in the PD model mouse brain during L‐dopa intervention. Mechanism studies suggest that the copper dyshomeostasis in the PD mouse brain was dominated by the expression levels of divalent metal transporter 1. The application of our probe in imaging Cu2+ dynamics in the mouse brain offers valuable insights into the copper‐related molecular mechanisms underlying neurodegenerative diseases.

Tobacco NtUBC1 and NtUBQ2 enhance salt tolerance by reducing sodium accumulation and oxidative stress through proteasome activation in Arabidopsis

The ubiquitin/proteasome system plays a crucial role in the regulation of plant responses to environmental stress. Here, we studied the involvement of the UBC1 and UBQ2 genes encoding a ubiquitin conjugating enzyme (E2) and ubiquitin extension protein, respectively, in the response to salt stress. Our results showed that the constitutive expression of tobacco NtUBC1 and NtUBQ2 in Arabidopsis thaliana improved salt tolerance, along with the lower Na+ level and higher K+/Na+ ratio compared to control plants. Moreover, the expression levels of sodium transporters, including AtHKT1 (High-Affinity K+ Transporter1) and AtSOS1 (Salt Overly Sensitive 1), were higher in NtUBC1- and NtUBQ2-Arabidopsis. However, the transcript level of AtNHX1 (Na+/H+ Exchanger 1) was similar between control and transgenic plants. After salt exposure, the activity of the 26S proteasome markedly increased in NtUBC1- and NtUBQ2-expressing plants; however, ubiquitinated protein levels decreased compared to control plants. Furthermore, higher activity of antioxidant enzymes and lower ROS production were observed in UBC1- and UBQ2-expressing plants. We further challenged atubc1, atubc2, and atubq2 single mutants and atubc1ubc2 double mutant lines with salt stress; interestingly, the salt sensitivity and sodium levels of the studied mutants were enhanced, while the potassium levels were reduced. However, the atubc1ubc2 double mutant illustrated a more severe phenotype than the single mutants, probably due to the redundant function of UBC1 and UBC2 in Arabidopsis. Taken together, NtUBC1 and NtUBQ2 enhance salt tolerance by enhancing 26S proteasome activity and reducing Na+ accumulation, ROS, and ubiquitinated/salt-denatured proteins.