Monophosphate Response Element Binding Protein Research Articles

Noncanonical UPR factor CREB3L2 drives immune evasion of triple-negative breast cancer through Hedgehog pathway modulation in T cells.

The unfolded protein response (UPR) pathway is crucial for tumorigenesis, mainly by regulating cancer cell stress responses and survival. However, whether UPR factors facilitate cell-cell communication between cancer cells and immune cells to drive cancer progression remains unclear. We found that adenosine 3',5'-monophosphate response element-binding protein 3-like protein 2 (CREB3L2), a noncanonical UPR factor, is overexpressed and activated in triple-negative breast cancer, where its cleavage releases a C-terminal fragment that activates the Hedgehog pathway in neighboring CD8+ T cells. The enhanced Hedgehog pathway represses CD8+ T cell activation and inhibits its cytotoxic effects. Consequently, overexpression of CREB3L2 not only promotes tumor growth but also causes resistance to immune checkpoint blockade (ICB). Inhibition of the Hedgehog pathway impedes the growth of CREB3L2-overexpressed tumors and sensitizes them to ICB therapy. In summary, we identified a previously unidentified mechanism by which the UPR pathway dictates cross-talk between cancer cells and immune cells, providing important anticancer therapeutic opportunities.

ZBED3 exacerbates hyperglycemia by promoting hepatic gluconeogenesis through CREB signaling

BackgroundElevated hepatic glucose production (HGP) is a prominent manifestation of impaired hepatic glucose metabolism in individuals with diabetes. Increased hepatic gluconeogenesis plays a pivotal role in the dysregulation of hepatic glucose metabolism and contributes significantly to fasting hyperglycemia in diabetes. Previous studies have identified zinc-finger BED domain-containing 3 (ZBED3) as a risk gene for type 2 diabetes (T2DM), and its single nucleotide polymorphism (SNPs) is closely associated with the fasting blood glucose level, suggesting a potential correlation between ZBED3 and the onset of diabetes. This study primarily explores the effect of ZBED3 on hepatic gluconeogenesis and analyzes the relevant signaling pathways that regulate hepatic gluconeogenesis. MethodsThe expression level of ZBED3 was assessed in the liver of insulin-resistant (IR)-related disease. RNA-seq and bioinformatics analyses were employed to examine the ZBED3-related pathway that modulated HGP. To investigate the role of ZBED3 in hepatic gluconeogenesis, the expression of ZBED3 was manipulated by upregulation or silencing using adeno-associated virus (AAV) in mouse primary hepatocytes (MPHs) and HHL-5 cells. In vivo, hepatocyte-specific ZBED3 knockout mice were generated. Moreover, AAV8 was employed to achieve hepatocyte-specific overexpression and knockdown of ZBED3 in C57BL/6 and db/db mice. Immunoprecipitation and mass spectrometry (IP-MS) analyses were employed to identify proteins that interacted with ZBED3. Co-immunoprecipitation (co-IP), glutathione S-transferase (GST) - pulldown, and dual-luciferase reporter assays were conducted to further elucidate the underlying mechanism of ZBED3 in regulating hepatic gluconeogenesis. ResultsThe expression of ZBED3 in the liver of IR-related disease models was found to be increased. Under the stimulation of glucagon, ZBED3 promoted the expression of hepatic gluconeogenesis-related genes PGC1A, PCK1, G6PC, thereby increasing HGP. Consistently, the rate of hepatic gluconeogenesis was found to be elevated in mice with hepatocyte-specific overexpression of ZBED3 and decreased in those with ZBED3 knockout. Additionally, the knockdown of ZBED3 in the liver of db/db mice resulted in a reduction in hepatic gluconeogenesis. Moreover, the study revealed that ZBED3 facilitated the nuclear translocation of protein arginine methyltransferases 5 (PRMT5) to influence the regulation of PRMT5-mediated symmetrical dimethylation of arginine (s-DMA) of cyclic adenosine monophosphate (cAMP) response element binding protein (CREB), which in turn affects the phosphorylation of CREB and ultimately promotes HGP. ConclusionsThis study indicates that ZBED3 promotes hepatic gluconeogenesis and serves as a critical regulator of the progression of diabetes.

A bitter taste receptor liganded by oxalic acid inhibits brown planthopper feeding by promoting CREB phosphorylation via the PI3K-AKT signaling pathway.

Insect gustatory receptors play a critical role in modulating feeding behaviors by detecting external nutritional cues through complex biochemical pathways. Bitter taste receptors are essential for insects to identify and avoid toxins. However, the detailed molecular and cellular mechanisms by which these receptors influence insect feeding behavior remain poorly understood. Our previous research identified the bitter taste receptor NlGr23a in the brown planthopper (BPH), which specifically binds to oxalic acid and elicits a significant feeding rejection response. In this study, using an Sf9 cell line stably expressing NlGr23a, we demonstrated that oxalic acid exposure significantly enhances phosphorylation of cyclic adenosine monophosphate response element-binding protein (CREB), a protein associated with BPH food consumption. Further analysis revealed the involvement of phosphatidylinositol 3-kinase (PI3K)-protein kinase B (AKT) signaling pathway in facilitating CREB phosphorylation upon activation by oxalic acid-NlGr23a binding. These in vitro findings were corroborated by in vivo experiments examining the expression profiles of relevant proteins and protein kinases in BPHs fed an oxalic acid-supplemented diet. Our results elucidate the biochemical cascades triggered by oxalic acid-NlGr23a interaction, advancing our understanding of insect gustatory receptor-mediated feeding behavior modulation and potentially informing novel strategies for integrated pest management.

Exploration of electroacupuncture at "Fengchi" (GB 20) and "Sishencong" (EX-HN 1) for attenuating learning and memory impairment in vascular dementia rats based on NMDAR/CREB/BDNF signaling pathway

To explore the mechanism of electroacupuncture (EA) at "Fengchi" (GB 20) and "Sishencong" (EX-HN 1) on learning and memory impairment in vascular dementia (VD) rats by observing the influences on the N-methyl-D-aspartate receptor (NMDAR)/cyclic adenosine monophosphate response element-binding protein (CREB)/brain-derived neurotrophic factor (BDNF) signaling pathway and the excitotoxicity induced by hippocampal calcium overload. Thirty-two male SD rats of SPF grade were selected and randomized into a normal group (6 rats), a sham-operation group (6 rats) and an operation group (20 rats). VD model was established with the modified Pulsinelli's four-vessel occlusion (4-VO) method. Twelve rats after successfully modeled were assigned randomly into a model group and an EA group, 6 rats in each one. In the EA group, EA was delivered at bilateral "Fengchi" (GB 20) and "Sishencong" (EX-HN 1), with the continuous wave, the frequency of 2 Hz and the electric current of 1 mA. Stimulation intensity was adjusted depending on the slightly trembling of rat head. EA was given once daily, 30 min each time; and EA intervention was delivered for 21 days continuously. Using Morris water maze test, the learning and memory function was assessed. The neuronal morphology in the hippocampal CA1 was observed with HE staining; the level of glutamate (GLU) in serum and hippocampal tissue, as well as the activity of calcium pump (Ca2+-ATP) in the hippocampus were detected using colorimetric method. The protein expression of NMDAR, calmodulin-dependent protein kinase Ⅱ (CaMKⅡ), phosphorylated calmodulin-dependent protein kinase Ⅱ (p-CaMKⅡ), phosphorylated cyclic phosphoradenosine effector element binding proteins (p-CREB), CREB, and BDNF in the hippocampal CA1 was detected using immunohistochemistry. The protein expression of NMDAR, CREB, p-CREB and BDNF in the hippocampal tissue was detected using Western blot method. Compared to the sham-operation group, in the model group, the escape latency was prolonged and the platform crossing times of rats were reduced (P<0.01), the hippocampal neuron structure was damaged to different degrees, the structure in hippocampal CA1 was loosened, the arrangement disorganized, with clear grid-like structure; the neuronal morphology was irregular, pyknosis and even dissolution occurred, glial cells increased, blood capillary was dilated and the inflammatory cells were infiltrated and scattered. The level of GLU in the serum and hippocampal tissue and the protein expression of hippocampal NMDAR were elevated (P<0.01), the activity of Ca2+-ATP and the protein expression of CaMKⅡ, p-CaMKⅡ, CREB, p-CREB and BDNF were reduced (P<0.01, P<0.05); and the ratio of p-CaMKⅡ/CaMKⅡ and that of p-CREB/CREB were dropped (P<0.05). In comparison with the model group, in the EA group, the escape latency was shortened and the platform crossing times of rats rose (P<0.01), the arrangement was improved in the hippocampal CA1, the neuronal morphology was intact, the nucleoli were clear relatively and the pyknosis or dissolution were attenuated, the numbers of glial cells reduced relatively, the dilation of blood capillary was alleviated. The level of GLU in the serum and hippocampal tissue and the protein expression of NMDAR were reduced in the hippocampal tissue (P<0.01), the activity of Ca2+-ATP and the protein expression of CaMKⅡ, p-CaMKⅡ, CREB, p-CREB and BDNF were elevated (P<0.05, P<0.01); and the ratio of p-CaMKⅡ/CaMKⅡ and that of p-CREB/CREB increased (P<0.05). EA at "Fengchi" (GB 20) and "Sishencong" (EX-HN 1) can attenuate learning and memory impairment in VD rats, which may be obtained by reducing GLU level in hippocampal tissue, inhibiting hippocampal excitotoxicity, mediating protein expression related to the NMDAR/CREB/BDNF signaling pathway, and maintaining neuronal survival and growth.

Hippocampal SENP3 mediates chronic stress-induced depression-like behaviors by impairing the CREB-BDNF signaling

Impaired signaling between cyclic adenosine monophosphate response element binding protein (CREB) and brain-derived neurotrophic factor (BDNF) in the hippocampus is generally considered to be the cause of depression. The mechanisms underlying the impairment of CREB-BDNF signaling under stress conditions are largely unclear. Small ubiquitin-like modifier (SUMO) specific peptidase 3 (SENP3) is a molecule that can regulate SUMOylation of target proteins related to synaptic plasticity. Its dynamic changes have been reported to be associated with neuronal damage in various models of central nervous disorders such as cerebral ischemia and traumatic brain injury. However, its role in depression is completely unknown. This problem was addressed in the present study. Our results showed that chronic unpredictable stress (CUS) triggered a specific increase in SENP3 expression in the hippocampus of non-stressed mice. Overexpression of SENP3 in the hippocampus of non-stressed mice elicited depression-like behaviors in the tail suspension test, forced swimming test, and sucrose preference test, accompanied by impairment of the CREB-BDNF signaling cascade in the hippocampus. Conversely, genetic silencing of SENP3 in the hippocampus suppressed the development of depression-like behaviors. Furthermore, infusion of SENP3-shRNA into the hippocampus failed to suppress CUS-induced depression-like behaviors when mice received genetic silencing CREB or BDNF in the hippocampus or inhibition of the BDNF receptor by K252a. Taken together, these results suggest that abnormally elevated SENP3 in the hippocampus leads to the development of depression-like behavior by impairing the CREB-BDNF signaling cascade. SENP3 in the hippocampus could be a promising target for the development of new antidepressants.

CREB3L1 deficiency impairs odontoblastic differentiation and molar dentin deposition partially through the TMEM30B

Odontoblasts are primarily responsible for synthesizing and secreting extracellular matrix proteins, which are crucial for dentinogenesis. Our previous single-cell profile and RNAscope for odontoblast lineage revealed that cyclic adenosine monophosphate responsive element-binding protein 3 like 1 (Creb3l1) was specifically enriched in the terminal differentiated odontoblasts. In this study, deletion of Creb3l1 in the Wnt1+ lineage led to insufficient root elongation and dentin deposition. Assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq) and RNA sequencing were performed to revealed that in CREB3L1-deficient mouse dental papilla cells (mDPCs), the genes near the closed chromatin regions were mainly associated with mesenchymal development and the downregulated genes were primarily related to biological processes including cell differentiation, protein biosynthesis and transport, all of which were evidenced by a diminished ability of odontoblastic differentiation, a significant reduction in intracellular proteins, and an even greater decline in extracellular supernatant proteins. Dentin matrix protein 1 (Dmp1), dentin sialophosphoprotein (Dspp), and transmembrane protein 30B (Tmem30b) were identified as direct transcriptional regulatory targets. TMEM30B was intensively expressed in the differentiated odontoblasts, and exhibited a significant decline in both CREB3L1-deficient odontoblasts in vivo and in vitro. Deletion of Tmem30b impaired the ability of odontoblastic differentiation, protein synthesis, and protein secretion in mDPCs. Moreover, overexpressing TMEM30B in CREB3L1-deficient mDPCs partially rescued the extracellular proteins secretion. Collectively, our findings suggest that CREB3L1 participates in dentinogenesis and facilitates odontoblastic differentiation by directly enhancing the transcription of Dmp1, Dspp, and other differentiation-related genes and indirectly promoting protein secretion partially via TMEM30B.

Thyroid Hormone Upregulates Cav1.2 Channels in Cardiac Cells via the Downregulation of the Channels' β4 Subunit.

Thyroid hormone binds to specific nuclear receptors, regulating the expression of target genes, with major effects on cardiac function. Triiodothyronine (T3) increases the expression of key proteins related to calcium homeostasis, such as the sarcoplasmic reticulum calcium ATPase pump, but the detailed mechanism of gene regulation by T3 in cardiac voltage-gated calcium (Cav1.2) channels remains incompletely explored. Furthermore, the effects of T3 on Cav1.2 auxiliary subunits have not been investigated. We conducted quantitative reverse transcriptase polymerase chain reaction, Western blot, and immunofluorescence experiments in H9c2 cells derived from rat ventricular tissue, examining the effects of T3 on the expression of α1c, the principal subunit of Cav1.2 channels, and Cavβ4, an auxiliary Cav1.2 subunit that regulates gene expression. The translocation of phosphorylated cyclic adenosine monophosphate response element-binding protein (pCREB) by T3 was also examined. We found that T3 has opposite effects on these channel proteins, upregulating α1c and downregulating Cavβ4, and that it increases the nuclear translocation of pCREB while decreasing the translocation of Cavβ4. Finally, we found that overexpression of Cavβ4 represses the mRNA expression of α1c, suggesting that T3 upregulates the expression of the α1c subunit in response to a decrease in Cavβ4 subunit expression.

Lactobacillus pentosus LPQ1 attenuates depressive-like behavior in BALB/C mice induced by chronic unpredictable mild stress (CUMS)

The development of depression is directly correlated with the concentration of 5-hydroxytryptophan (5-HTP). It has been demonstrated that Lactobacillus increases 5-HTP secretion, however, it is unclear how this elevated 5-HTP secretion results in antidepressant benefits. Mice exposed to chronic unpredictable mild stress (CUMS) were administered L. pentosus LPQ1 by gavage for 35 days. According to our findings, CUMS-exposed mice showed an improvement in body weight when treated with L. pentosus LPQ1. Furthermore, we discovered that in mice given CUMS, L. pentosus LPQ1 raised neurotransmitter levels and decreased behavior resembling depression. Also, L. pentosus LPQ1 upregulated hippocampal 5-HT1A, phosphorylated cyclic adenosine monophosphate responsive element binding protein (p-CREB)/CREB, brain-derived neurotrophic factor (BDNF), and phosphorylated tropomyosin kinase B (p-TrκB/TrκB) expression of CUMS-exposed mice. Additionally, L. pentosus LPQ1 is associated with an increase in the number of helpful bacteria in the gut microbiota, including Unclassified-f-Lachnospiracea, Lachnospiraceae-NK4A136-group, Eubacterium_xylanophilum_group. In summary, L. pentosus LPQ1 attenuated CUMS-induced depression by restoring 5-HTP-related 5-HT1A-CREB-BDNF-TrκB signaling. Interestingly, the improvement of depressive-like behavior by L. pentosus LPQ1 is also related to the improvement of gut microbiota dysbiosis. According to our research, L. pentosus LPQ1 may be a useful therapeutic alternative for depressed people.

Nimodipine Used with Vincristine: Protects Schwann Cells and Neuronal Cells from Vincristine-Induced Cell Death but Increases Tumor Cell Susceptibility.

The chemotherapeutic agent vincristine is commonly used for a variety of hematologic cancers, as well as solid tumors of the head and neck, bronchial carcinoma, as part of the procarbazine, lomustine and vincristine (PCV) regimen, for glioma. Damage to nerve tissue (neuropathy) is often dose-limiting and restricts treatment. Nimodipine is a calcium antagonist that has also shown neuroprotective properties in preliminary studies. In this approach here, we investigated the effects of the combination of vincristine and nimodipine on three cancer cell lines (A549, SAS and LN229) and neuronal cells (RN33B, SW10). Fluorescence microscopy, lactate dehydrogenase (LDH) assays and Western blot analyses were used. Nimodipine was able to enhance the cell death effects of vincristine in all tumor cells, while neuronal cells were protected and showed less cell death. There was an opposite change in the protein levels of Ak strain transforming/protein kinase B (AKT) in tumor cells (down) and neuronal cells (up), with simultaneous increased protein levels of cyclic adenosine monophosphate response element-binding protein (CREB) in all cell lines. In the future, this approach may improve tumor response to chemotherapy and reduce unwanted side effects such as neuropathy.

Berberine Alleviates Sevoflurane Anesthesia-Induced Cognitive Dysfunction in Neonatal Mice via Regulating CREB1.

Sevoflurane has been shown to stimulate neurotoxicity and lead to cognitive impairment. Berberine is known for its role in regulating nervous system diseases, including cognitive dysfunction. This study aimed to investigate the effects of berberine on cognitive dysfunction induced by sevoflurane anesthesia and its potential mechanisms. In the in vivo study, neonatal mice were subjected to sevoflurane anesthesia to induce cognitive dysfunction. The cognitive function of the neonatal mice was evaluated using the Morris water maze test, open field test, and tail suspension test. Enzyme-linked immunosorbent assay (ELISA) was utilized to assess the levels of inflammatory factors. Immunohistochemistry (IHC) was conducted to detect ionized calcium-binding adaptor molecule 1 (IBA-1)-positive cells and cleaved caspase-3-positive cells in the hippocampus of the neonatal mice. Western blotting was used to measure the levels of cyclic adenosine monophosphate (cAMP) response element-binding protein 1 (CREB1) in hippocampal tissues and neurons. Hippocampal neurons were isolated from the hippocampus of neonatal mice. These neurons were treated with berberine or subjected to cell transfection. The cell counting kit-8 (CCK-8) assay and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay were conducted to measure cell viability and apoptosis of hippocampal neurons in vitro. Berberine significantly attenuated sevoflurane-induced cognitive impairment and inflammation in neonatal mice (p < 0.05 or p < 0.01). Additionally, berberine reduced sevoflurane-triggered neuronal apoptosis in the hippocampus of neonatal mice (p < 0.01). Sevoflurane markedly decreased CREB1 expression in the hippocampus of neonatal mice (p < 0.01), which was elevated by berberine treatment (p < 0.01). Mechanistically, sevoflurane significantly suppressed cell viability and promoted cell apoptosis of hippocampal neurons (p < 0.0001 or p < 0.01), which were mitigated by berberine (p < 0.05, p < 0.01, or p < 0.001). Furthermore, berberine significantly elevated CREB1 expression in sevoflurane-treated hippocampal neurons (p < 0.01). The beneficial effects of berberine on cell viability and apoptosis in sevoflurane-treated hippocampal neurons were blocked by CREB1 depletion (p < 0.001). Our results demonstrated that CREB1 was significantly decreased in the hippocampus of sevoflurane-treated neonatal mice in vivo and in sevoflurane-treated hippocampal neurons in vitro. This decrease was mitigated by berberine treatment. Moreover, berberine improved sevoflurane anesthesia-induced cognitive impairment in neonatal mice by attenuating neuronal inflammation and apoptosis in vivo. The inhibitory effects of berberine on sevoflurane-induced cell apoptosis were reversed by CREB1 downregulation. These findings indicate that berberine protects against sevoflurane anesthesia-induced cognitive impairment by reducing apoptosis of hippocampal neurons, partially through increasing CREB1 expression.

The Anti-Melanogenic Effects of Ganodermanontriol from the Medicinal Mushroom Ganoderma lucidum through the Regulation of the CREB and MAPK Signaling Pathways in B16F10 Cells.

Ganoderma lucidum, a member of the Basidiomycetes family, is attracting attention for its medicinal potential due to its biological activity and the presence of numerous bioactive compounds. Although it is known that extracts of this mushroom inhibit melanin production, there are few reports on a single substance associated with this effect. In this study, we identified ganodermanontriol (GT), a novel compound from G. lucidum, that effectively inhibited melanin biosynthesis in B16F10 cells. GT inhibits melanin production by suppressing the expression of cellular tyrosinase proteins and microphthalmia-related transcription factor (MITF). Furthermore, GT affects the phosphorylation of cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB) and mitogen-activated protein kinase (MAPK) signaling molecules, which are involved in melanogenesis in B16F10 cells. Finally, the biosynthesis of GT and other substances by G. lucidum was evaluated using HPLC analysis. Thus, this study revealed the mechanism by which GT in G. lucidum inhibits melanin production in B16F10 cells, and these findings will contribute to promoting the potential use of this mushroom in the future.

Electroacupuncture Alleviates Streptozotocin-Induced Diabetic Neuropathic Pain via the TRPV1-Mediated CaMKII/CREB Pathway in Rats.

Diabetic neuropathic pain (DNP) is a diabetic complication that causes severe pain and deeply impacts the quality of the sufferer's daily life. Currently, contemporary clinical treatments for DNP generally exhibit a deficiency in effectiveness. Electroacupuncture (EA) is recognized as a highly effective and safe treatment for DNP with few side effects. Regrettably, the processes via which EA alleviates DNP are still poorly characterized. Transient receptor potential vanilloid 1 (TRPV1) and phosphorylated calcium/calmodulin-dependent protein kinase II (p-CaMKII) are overexpressed on spinal cord dorsal horn (SCDH) in DNP rats, and co-localization is observed between them. Capsazepine, a TRPV1 antagonist, effectively reduced nociceptive hypersensitivity and downregulated the overexpression of phosphorylated CaMKIIα in rats with DNP. Conversely, the CaMKII inhibitor KN-93 did not have any impact on TRPV1. EA alleviated heightened sensitivity to pain caused by nociceptive stimuli and downregulated the level of TRPV1, p-CaMKIIα, and phosphorylated cyclic adenosine monophosphate response element-binding protein (p-CREB) in DNP rats. Intrathecal injection of capsaicin, on the other hand, reversed the above effects of EA. These findings indicated that the CaMKII/CREB pathway on SCDH is located downstream of TRPV1 and is affected by TRPV1. EA alleviates DNP through the TRPV1-mediated CaMKII/CREB pathway.

Arachidonic acid regulates pluripotency by modulating cellular energetics via fatty acid synthesis and mitochondrial fission

Arachidonic acid (AA) is an important omega-6 fatty acid that can be metabolised into an impressive spectrum of biologically active mediators participating in various cellular functions. Studies have shown that fatty acid synthesis is enhanced in embryonic stem cells (ESCs), and it is crucial for the cellular reprogramming of somatic cells into induced pluripotent stem cells (iPSCs). Fatty acid synthesis increases the cellular lipid contents and, in turn, promotes mitochondrial fission and cellular reprogramming. AA was found to induce acetyl-CoA carboxylase 1 (ACC1) expression, a major enzyme in fatty acid synthesis. In this study, we have investigated the regulation of pluripotency, fatty acid synthesis and mitochondrial activities of the human induced pluripotent stem cells (hiPSCs) and the human embryonal carcinoma (hEC) NTERA-2 cells upon treatment with varying concentrations of AA. Our results indicate that a lower concentration of AA can increase pluripotency, as evidenced by an increased expression of pluripotency markers, increased fatty acid synthesis as evidenced by lipid estimation and modulated mitochondrial fission, as evidenced by mitotracker staining for fissioned mitochondria. Moreover, higher concentrations of AA-induced the opposite effect, leading to pluripotent stem cell differentiation. Molecular docking simulations predicted the possible interactions between AA and its metabolites with fatty acid synthesis regulators ACC1 and CREB1 (Cyclic adenosine monophosphate Response Element Binding Protein 1) as a mechanism for AA regulating pluripotency.

COX-2 optimizes cardiac mitochondrial biogenesis and exerts a cardioprotective effect during sepsis

BackgroundSeptic cardiomyopathy is a component of multiple organ dysfunction in sepsis. Mitochondrial dysfunction plays an important role in septic cardiomyopathy. Studies have shown that cyclooxygenase-2 (COX-2) had a protective effect on the heart, and prostaglandin E2 (PGE2), the downstream product of COX-2, was increasingly recognized to have a protective effect on mitochondrial function. ObjectiveThis study aims to demonstrate that COX-2/PGE2 can protect against septic cardiomyopathy by regulating mitochondrial function. MethodsCecal ligation and puncture (CLP) was used to establish a mouse model of sepsis and RAW264.7 macrophages and H9C2 cells were used to simulate sepsis in vitro. The NS-398 and celecoxib were used to inhibit the activity of COX-2. ZLN005 and SR18292 were used to activate or inhibit the PGC-1α activity. The mitochondrial biogenesis was examined through the Mitotracker Red probe, mtDNA copy number, and ATP content detection. ResultsThe experimental data suggested that COX-2 inhibition attenuated PGC-1α expression thus decreasing mitochondrial biogenesis, whereas increased PGE2 could promote mitochondrial biogenesis by activating PGC-1α. The results also showed that the effect of COX-2/PGE2 on PGC-1α was mediated by the activation of cyclic adenosine monophosphate (cAMP) response element binding protein (CREB). Finally, the effect of COX-2/PGE2 on the heart was also verified in the septic mice. ConclusionCollectively, these results suggested that COX-2/PGE2 pathway played a cardioprotective role in septic cardiomyopathy through improving mitochondrial biogenesis, which has changed the previous understanding that COX-2/PGE2 only acted as an inflammatory factor.

Luteolin promotes neuronogenesis in hippocampus of chronic unpredictable mild stress rats and primary hippocampus of fetal rats.

To investigate the effects of luteolin on chronic unpredictable mild stress (CUMS)-induced depressive rats and corticosterone (CORT)-induced depressive primary hippocampal neurons, and to elucidate the mechanism behind the action. The antidepressant mechanism of luteolin was studied by using CUMS rat model and primary hippocampal neurons in fetal rats. In vivo, novelty suppressed feeding, open-field and sucrose preference tests as well as Morris water maze were evaluated. The content of brain derived neurotrophic factor (BDNF), 5-hydroxytryptamine (5-HT), norepinephrine (NE), and dopamine (DA) in serum were detected by enzyme-linked immunosorbent assay. The mechanisms of luteolin were explored based on neurotrophin and hippocampal neurogenesis, and proliferation. Survival of the septo-temporal axis in hippocampus was assayed using the 5-bromo-2-deoxyuridine (BrdU), the expression of BDNF, neurotrophin-3 (NT-3), and nerve growth factor (NGF) in hippocampus dentate gyrus region were measured by Western-blotting. In vitro, BDNF, NT-3, tropomyosin receptor kinase B (TrkB), and phosphorylated cyclic adenosine monophosphate responsive element binding protein (p-CREB) were detected through the high content analysis (HCA) to investigate neurotrophin and apoptosis. Induction of CUMS in rats induced depressive symptoms, while luteolin significantly enhanced sucrose consumption, decreased feeding latency, increased locomotor activity, escape latency, distance of target quadrant and regulated the content of depressive-like biomarkers. Histology analysis revealed that luteolin increased the abundance of new born neurons that had been labeled with BrdU, BrdU + neuronal nuclear antigen, and BrdU + doublecortin in septo-temporal axis of S2 (mid-septal) and T3 (mid-temporal). Moreover, expression of BDNF, NT-3, and NGF increased significantly in the septo-temporal axis of S2 and T3. HCA showed increased expression of BDNF, NT-3, TrkB and p-CREB in primary hippocampal neurons. The results provided direct evidence that luteolin has an antidepressant effect and could effectively promote the regeneration of the septotemporal axis nerve and hippocampal neuronutrition, which suggested that the antidepressant effect of luteolin may be related to hippocampal neurogenesis.

Exploring the analgesic potential of isorhamnetin: insights from formalin-induced pain and diabetic neuropathy models.

Isorhamnetin, a naturally occurring flavonoid compound, holds paramount importance as a primary constituent within several medicinal plants, exhibiting profound pharmacological significance. The aim of this study is to investigate the pain-relieving attributes of isorhamnetin in murine models through both formalin-induced pain and diabetic neuropathy scenarios. To achieve our objective, isorhamnetin was orally administered to mice at varying dosage levels (10 to 100 mg/kg). Pain-related behaviors were assessed using the formalin test during its secondary phase. Additionally, the potential pain-alleviating effect of isorhamnetin was evaluated in a diabetic neuropathy model induced by streptozotocin. Additionally, we carried out advanced interventions using naloxone, which is a well-known antagonist of opioid receptors, yohimbine, which blocks α2-adrenergic receptors, and methysergide, which inhibits serotonergic receptors, during the formalin test. The oral intake of isorhamnetin showed a decrease in behaviors associated with pain that was proportional to the dose observed during the second phase of the formalin test when induced by formalin. In the diabetic neuropathy model, isorhamnetin administration effectively reversed the reduced pain threshold observed. Notably, naloxone, the opioid receptor antagonist, effectively counteracted the pain-relieving effect produced by isorhamnetin in the formalin test, whereas yohimbine and methysergide did not yield similar outcomes. Isorhamnetin also led to a reduction in elevated spinal cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) levels triggered by formalin, with this effect reversed by pre-treatment with naloxone. The compound also suppressed heightened spinal phosphorylated CREB (p-CREB) levels caused by diabetic neuropathy. This research determined that isorhamnetin has notable abilities to relieve pain in models of formalin-induced pain and diabetic neuropathy. The pain-relieving mechanism of isorhamnetin in the formalin-induced pain model seems to be connected to the activation of spinal opioid receptors and the adjustment of CREB protein amounts. This insight improves our knowledge of how isorhamnetin could be used therapeutically to treat pain conditions stemming from formalin-induced pain and diabetic neuropathy.

Eicosapentaenoic Acid Rescues Cav1.2-L-Type Ca2+ Channel Decline Caused by Saturated Fatty Acids via Both Free Fatty Acid Receptor 4-Dependent and -Independent Pathways in Cardiomyocytes.

Dietary intake of omega-3 polyunsaturated fatty acids (eicosapentaenoic acid, EPA) exerts antiarrhythmic effects, although the mechanisms are poorly understood. Here, we investigated the possible beneficial actions of EPA on saturated fatty acid-induced changes in the L-type Ca2+ channel in cardiomyocytes. Cardiomyocytes were cultured with an oleic acid/palmitic acid mixture (OAPA) in the presence or absence of EPA. Beating rate reduction in cardiomyocytes caused by OAPA were reversed by EPA. EPA also retrieved a reduction in Cav1.2 L-type Ca2+ current, mRNA, and protein caused by OAPA. Immunocytochemical analysis revealed a distinct downregulation of the Cav1.2 channel caused by OAPA with a concomitant decrease in the phosphorylated component of a transcription factor adenosine-3',5'-cyclic monophosphate (cAMP) response element binding protein (CREB) in the nucleus, which were rescued by EPA. A free fatty acid receptor 4 (FFAR4) agonist TUG-891 reversed expression of Cav1.2 and CREB mRNA caused by OAPA, whereas an FFAR4 antagonist AH-7614 abolished the effects of EPA. Excessive reactive oxygen species (ROS) accumulation caused by OAPA decreased Cav1.2 and CREB mRNA expressions, which was reversed by an ROS scavenger. Our data suggest that EPA rescues cellular Cav1.2-Ca2+ channel decline caused by OAPA lipotoxicity and oxidative stresses via both free fatty acid receptor 4-dependent and -independent pathways.

Analysis of the functional role and mRNA expression of GABA B R in the nucleus accumbens of cocaine-addicted rats.

Drug addiction is a social and medical problem that must be urgently addressed. The nucleus accumbens (NAc) is closely related to addiction-related learning memory, and γ-aminobutyric acid type B receptor (GABA B R) is a potential target for the treatment of drug addiction. However, the role of GABA B R activity levels in the NAc in cocaine addiction is unclear. In this study, we established an animal model of cocaine dependence, modulated the level of GABA B R activity, applied a conditioned place preference assay (CPP) to assess the role of the NAc in reconsolidation of addiction memory, evaluated learning and memory functions by behavioral experiments, examined the expression of GB1, GB2, cyclic adenosine monophosphate response element binding protein (CREB), p-CREB, protein kinase A (PKA), protein kinase (ERK), and Brain-derived neurotrophic factor (BDNF) in the NAc by molecular biology experiments, and screened differentially significantly expressed genes by transcriptome sequencing. Our study showed that the GABA B receptor agonist baclofen (BLF) had a significant effect on locomotor distance in rats, promoted an increase in GABA levels and significantly inhibited the PKA and ERK1/2/CREB/BDNF signaling pathways. Moreover, transcriptome sequencing showed that GABA B R antagonist intervention identified a total of 21 upregulated mRNAs and 21 downregulated mRNAs. The differentially expressed (DE) mRNA genes were mainly enriched in tyrosine metabolism; however, further study is needed. GABA B R activity in the NAc is involved in the regulation of cocaine addiction and may play an important role through key mRNA pathways.

Signaling pathways in the treatment of Alzheimer's disease with acupuncture: a narrative review.

To date, there is no effective treatment for Alzheimer's disease (AD), a progressive neurodegenerative disorder that is increasing in prevalence worldwide. The objective of this review was to summarize the core targets and signaling pathways involved in acupuncture treatment for AD. We reviewed numerous signaling pathways, including mammalian target of rapamycin (mTOR), phosphatidylinositol 3-kinase-protein kinase B (PI3 K/Akt), adenosine monophosphate-activated protein kinase (AMPK), mitogen-activated protein kinase (MAPK), nuclear factor (NF)-kB, p53, Wnt, nitric oxide (NO), Janus kinase / signal transducer and activator of transcription (JAK/ STAT), RhoA/ROCK (Rho-associated protein kinase) and Ca2+/ calmodulin-dependent protein kinase II (CaMKII) / cyclic adenosine monophosphate-response element-binding protein (CREB). The relevant data were obtained from PubMed, EMBASE, Web of Science, China National Knowledge Infrastructure (CNKI) and Wanfang databases. In summary, the effects of acupuncture are mediated by multiple targets and pathways. Furthermore, acupuncture can improve pathological changes associated with AD (such as abnormal deposition of amyloid (A)β, tau hyperphosphorylation, synaptic dysfunction and neuronal apoptosis) through multiple signaling pathways. Overall, our findings provide a basis for future research into the effects of acupuncture on AD.

Chronic ingestion of soy peptide supplementation reduces aggressive behavior and abnormal fear memory caused by juvenile social isolation

Juvenile loneliness is a risk factor for psychopathology in later life. Deprivation of early social experience due to peer rejection has a detrimental impact on emotional and cognitive brain function in adulthood. Accumulating evidence indicates that soy peptides have many positive effects on higher brain function in rodents and humans. However, the effects of soy peptide use on juvenile social isolation are unknown. Here, we demonstrated that soy peptides reduced the deterioration of behavioral and cellular functions resulting from juvenile socially-isolated rearing. We found that prolonged social isolation post-weaning in male C57BL/6J mice resulted in higher aggression and impulsivity and fear memory deficits at 7 weeks of age, and that these behavioral abnormalities, except impulsivity, were mitigated by ingestion of soy peptides. Furthermore, we found that daily intake of soy peptides caused upregulation of postsynaptic density 95 in the medial prefrontal cortex and phosphorylation of the cyclic adenosine monophosphate response element binding protein in the hippocampus of socially isolated mice, increased phosphorylation of the adenosine monophosphate-activated protein kinase in the hippocampus, and altered the microbiota composition. These results suggest that soy peptides have protective effects against juvenile social isolation-induced behavioral deficits via synaptic maturation and cellular functionalization.