Lycium Barbarum Polysaccharides Improves Cognitive Functions in ICV-STZ-Induced Alzheimer's Disease Mice Model by Improving the Synaptic Structural Plasticity and Regulating IRS1/PI3K/AKT Signaling Pathway.

Lycium barbarum polysaccharide (LBP) have a certain curative effect on hypoglycemic and neuroprotective effects, but the specific mechanism is unclear and needs to be further explored. This study aimed to clarify the mechanisms of LBP in the treatment of ICV-STZ mice model of AD from the perspectives of insulin resistance, IRS1/PI3K/AKT signaling pathway, and synaptic protein expression. We used male C57BL/6J mice injected with STZ (3 mg/kg) in the lateral ventricle as an AD model. After treatment with LBP, the learning and memory abilities of ICV-STZ mice were enhanced, and the pathological changes in brain tissue were alleviated. LBP can regulate the expression of proteins related to the IRS1/PI3K/AKT signaling pathway and thereby reducing Aß deposition and tau protein phosphorylation in the brain of ICV-STZ mice. In addition, LBP also can up-regulate the expression of synaptic proteins. The results indicated that LBP played a neuroprotective role by regulating the IRS1/PI3K/AKT pathway, inhibiting tau protein hyperphosphorylation and improving the expression levels of synapse-related proteins.

AZGP1 in POMC neurons modulates energy homeostasis and metabolism through leptin-mediated STAT3 phosphorylation.

Zinc-alpha2-glycoprotein (AZGP1) has been implicated in peripheral metabolism; however, its role in regulating energy metabolism in the brain, particularly in POMC neurons, remains unknown. Here, we show that AZGP1 in POMC neurons plays a crucial role in controlling whole-body metabolism. POMC neuron-specific overexpression of Azgp1 under high-fat diet conditions reduces energy intake, raises energy expenditure, elevates peripheral tissue leptin and insulin sensitivity, alleviates liver steatosis, and promotes adipose tissue browning. Conversely, mice with inducible deletion of Azgp1 in POMC neurons exhibit the opposite metabolic phenotypes, showing increased susceptibility to diet-induced obesity. Notably, an increase in AZGP1 signaling in the hypothalamus elevates STAT3 phosphorylation and increases POMC neuron excitability. Mechanistically, AZGP1 enhances leptin-JAK2-STAT3 signaling by interacting with acylglycerol kinase (AGK) to block its ubiquitination degradation. Collectively, these results suggest that AZGP1 plays a crucial role in regulating energy homeostasis and glucose/lipid metabolism by acting on hypothalamic POMC neurons.

Food perception promotes phosphorylation of MFFS131 and mitochondrial fragmentation in liver.

Liver mitochondria play a central role in metabolic adaptations to changing nutritional states, yet their dynamic regulation upon anticipated changes in nutrient availability has remained unaddressed. Here, we found that sensory food perception rapidly induced mitochondrial fragmentation in the liver through protein kinase B/AKT (AKT)-dependent phosphorylation of serine 131 of the mitochondrial fission factor (MFFS131). This response was mediated by activation of hypothalamic pro-opiomelanocortin (POMC)-expressing neurons. A nonphosphorylatable MFFS131G knock-in mutation abrogated AKT-induced mitochondrial fragmentation in vitro. In vivo, MFFS131G knock-in mice displayed altered liver mitochondrial dynamics and impaired insulin-stimulated suppression of hepatic glucose production. Thus, rapid activation of a hypothalamus-liver axis can adapt mitochondrial function to anticipated changes of nutritional state in control of hepatic glucose metabolism.

AMP-activated protein kinase can be allosterically activated by ADP but AMP remains the key activating ligand.

The AMP-activated protein kinase (AMPK) is a sensor of cellular energy status. When activated by increases in ADP:ATP and/or AMP:ATP ratios (signalling energy deficit), AMPK acts to restore energy balance. Binding of AMP to one or more of three CBS repeats (CBS1, CBS3, CBS4) on the AMPK-γ subunit activates the kinase complex by three complementary mechanisms: (i) promoting α-subunit Thr172 phosphorylation by the upstream kinase LKB1; (ii) protecting against Thr172 dephosphorylation; (iii) allosteric activation. Surprisingly, binding of ADP has been reported to mimic the first two effects, but not the third. We now show that at physiologically relevant concentrations of Mg.ATP2- (above those used in the standard assay) ADP binding does cause allosteric activation. However, ADP causes only a modest activation because (unlike AMP), at concentrations just above those where activation becomes evident, ADP starts to cause competitive inhibition at the catalytic site. Our results cast doubt on the physiological relevance of the effects of ADP and suggest that AMP is the primary activator in vivo. We have also made mutations to hydrophobic residues involved in binding adenine nucleotides at each of the three γ subunit CBS repeats of the human α2ß2γ1 complex and examined their effects on regulation by AMP and ADP. Mutation of the CBS3 site has the largest effects on all three mechanisms of AMP activation, especially at lower ATP concentrations, while mutation of CBS4 reduces the sensitivity to AMP. All three sites appear to be required for allosteric activation by ADP.

Regulation of STAT1 and STAT4 Expression by Growth Factor and Interferon Supplementation in Sjögren's Syndrome Cell Culture Models.

Our goal was to investigate the effects of epidermal growth factor (EGF) and interferons (IFNs) on signal transducer and activator of transcription STAT1 and STAT4 mRNA and active phosphorylated protein expression in Sjögren's syndrome cell culture models. iSGECs (immortalized salivary gland epithelial cells) and A253 cells were treated with EGF, IFN-alpha, -beta, -gamma, or mitogen-activated protein kinase p38 alpha (p38-MAPK) inhibitor for 0-24-48-72 h. STAT1 and STAT4 mRNA expression was quantified by qRT-PCR. Untreated and treated cells were compared using the delta-delta-CT method based on glyceraldehyde-3-phosphate dehydrogenase (GAPDH) normalized relative fold changes. phospho-tyrosine-701-STAT1 and phospho-serine-721-STAT4 were detected by Western blot analysis. STAT4 mRNA expression decreased 48 h after EGF treatment in A253 cells, immortalized salivary gland epithelial cells iSGECs nSS2 (sicca patient origin), and iSGECs pSS1 (anti-SSA negative Sjögren's Syndrome patient origin). EGF and p38-MAPK inhibitor decreased A253 STAT4 mRNA levels. EGF combined with IFN-gamma increased phospho-STAT4 and phospho-STAT1 after 72 h in all cell lines, suggesting additive effects for phospho-STAT4 and a major effect from IFN-gamma for phospho-STAT1. pSS1 and nSS2 cells responded differently to type I and type II interferons, confirming unique functional characteristics between iSGEC cell lines. EGF/Interferon related pathways might be targeted to regulate STAT1 and STAT4 expression in salivary gland epithelial cells. Further investigation is required learn how to better target the Janus kinases/signal transducer and activator of transcription proteins (JAK/STAT) pathway-mediated inflammatory response in Sjögren's syndrome.

Effect of moxibustion combined with intraperitoneal injection of benazepril on endoplasmic reticulum stress-related protein phosphorylation in rats with chronic heart failure. / è‰¾ç¸è”åˆè´é‚£æ™®åˆ©å¯¹æ ¢æ€§å¿ƒåŠ›è¡°ç«­å¤§é¼ å¿ƒè‚Œå† è´¨ç½‘åº”æ¿€ç›¸å ³è›‹ç™½ç£·é ¸åŒ–è¡¨è¾¾çš„å½±å“.

OBJECTIVES: To observe the effect of moxibustion at "Xinshu"(BL15) and "Feishu"(BL13) combined with intraperitoneal injection of benazepril on cardiac function and phosphorylation of protein kinase R-like endoplasmic reticulum kinase (PERK) and eukaryotic initiation factor 2α (elF2α) proteins in myocardium of rats with chronic heart failure (CHF), so as to explore its potential mechanism underlying improvement of CHF. METHODS: A total of 42 male SD rats were randomly assigned to blank control (n=10), CHF model (n=7), medication (benazepril, n=8), moxibustion (n=8) and moxibustion+benazepril (n=9) groups, after cardiac ultrasound model identification and elimination of the dead. The CHF model was established by intraperitoneal injection of doxorubicin hydrochloride (DOX), once every week for 6 weeks. Mild moxibustion was applied to bilateral BL15 and BL13 regions for 20 min, once daily for 3 weeks. The rats of the medication group and moxibustion+benazepril group (benazepril was given first, followed by moxibustion) received intraperitoneal injection of benazepril (0.86 mg/kg) solution once daily for 3 weeks . The cardiac ejection fraction (EF) and left ventricular fractional shortening (FS) were measured using echocardiography. Histopathological changes of the cardiac muscle tissue were observed under light microscope after hematoxylin-eosin (H.E.) staining. Serum contents of B-type brain natriuretic peptide (BNP) and angiotensin Ⅱ (AngⅡ) were measured by enzyme-linked immunosorbent assay (ELISA). The expressions of phospho-PERK (p-PERK) and phospho-elF2α (p-elF2α) in the myocardium were detected by Western blot. RESULTS: Compared with the blank control group, the EF and FS of the left cardiac ventricle were significantly decreased (P<0.01), while the contents of serum BNP and AngⅡ, and expression levels of p-PERK and p-eIF2α significantly increased in the model group (P<0.01). In comparison with the model group, both the decreased EF and FS and the increased BNP and AngⅡ contents as well as p-PERK and p-elF2α expression levels were reversed by moxibustion, medication and moxibustion+benazepril (P<0.01). The effects of moxibustion+benazepril were markedly superior to those of simple moxibustion and simple medication in raising the levels of EF and FS rate and in down-regulating the contents of BNP, Ang Ⅱ, levels of p-PERK and p-elF2α (P<0.01, P<0.05). Outcomes of H.E. staining showed irregular arrangement of cardiomyocytes, cell swelling, vacuole and inflammatory infiltration in the model group, which was relatively milder in the 3 treatment groups. The effects of moxibustion+benazepril were superior to those of moxibustion or benazepril. CONCLUSIONS: Moxibustion combined with Benazepril can improve the cardiac function in CHF rats, which may be related to its functions in down-regulating the expression levels of myocardial p-PERK and p-elF2α to inhibit endoplasmic reticulum stress response.

Regulation of hypothalamic reactive oxygen species and feeding behavior by phosphorylation of the beta 2 thyroid hormone receptor isoform.

Unlike other thyroid hormone receptors (THRs), the beta 2 isoform (THRB2) has a restricted expression pattern and is uniquely and abundantly phosphorylated at a conserved serine residue S101 (S102 in humans). Using tagged and or phosphorylation-defective (S101A) THRB2 mutant mice, we show that THRB2 is present in a large subset of POMC neurons and mitigates ROS accumulation during ROS-triggering events, such as fasting/refeeding or high fat diet (HFD). Excessive ROS accumulation in mutant POMC neurons was accompanied by a skewed production of orexigenic/anorexigenic hormones, resulting in elevated food intake. The prolonged exposure to pathogenic hypothalamic ROS levels during HFD feeding lead to a significant loss of POMC neurons in mutant versus wild-type (WT) mice. In cultured cells, the presence of WT THRB2 isoform, but not other THRs, or THRB2S101A, reduced ROS accumulation upon exogenous induction of oxidative stress by tert-butyl hydroperoxide. The protective function of phospho-THRB2 (pTHRB2) did not require thyroid hormone (TH), suggesting a TH-independent role of the THRB2 isoform, and phospho-S101 in particular, in regulating oxidative stress. We propose that pTHRB2 has a fundamental role in neuronal protection against ROS cellular damage, and mitigates hypothalamic pathological changes found in diet-induced obesity.

Xiebai San alleviates acute lung injury by inhibiting the phosphorylation of the ERK/Stat3 pathway and regulating multiple metabolisms.

BACKGROUND: Acute lung injury (ALI) often leads to serious respiratory diseases with high incidence rates and mortality. For centuries, Xiebai San (XBS) has been a classical traditional Chinese medicine (TCM) about respiratory illness such as pneumonia in children. However, the related mechanism of XBS against ALI remains indistinct. PURPOSE: To reveal specific targets of XBS in lipopolysaccharide (LPS)-induced ALI mice using integrated pharmacology. STUDY DESIGN: The integrated method was to expound mechanism and targets of XBS inhibited ALI. METHODS: The primary components in XBS were identified by ultra high performance liquid chromatography-quadrupole time of flight-mass spectrometry (UHPLC-QTOF-MS). The potential drug targets were established using network pharmacology. The anti-ALI effect of XBS was evaluated in mice. Additionally, therapeutic targets were screened by integrating metabolome and transcriptome and verified in lung tissue. RESULTS: In total, 163 chemical components were identified in XBS, and a network of "3 drugs-18 components-86 targets" for XBS against ALI was constructed. In ALI mice, XBS alleviated lung inflammation by decreasing permeation and expression of neutrophils, tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß) in bronchoalveolar lavage fluid (BALF), serum, and lung tissue. Next, the transcriptome of lung tissue was analyzed and enriched, indicating the importance of mitogen-activated protein kinase (MAPK), Janus kinase-signal transducer and activator of transcription (JAK-STAT), and others, which was consistent with network pharmacology prediction. Also, western blotting and immunohistochemistry results showed that XBS was against ALI mainly by inhibiting extracellular signal regulated kinase (ERK) and signal transducer and activator of transcription 3 (Stat3) phosphorylation. In addition, the metabolome of lung tissue revealed that XBS mainly regulated pathways involved in arachidonic acid, glycerophospholipid, and tryptophan metabolisms. The expression levels of leukotriene, phosphatidylcholine, kynurenine, and others were also verified. CONCLUSION: XBS alleviated inflammation of ALI by inhibiting the phosphorylation of the ERK/Stat3 pathway and regulating arachidonic acid, glycerophospholipid, and tryptophan metabolisms. This study will guide clinical precision medicine and promote modernization of XBS.

Gastrodin regulates the TLR4/TRAF6/NF-κB pathway to reduce neuroinflammation and microglial activation in an AD model.

BACKGROUND: Gastrodia elata (Orchidaceae) is a medicinal plant used in traditional Chinese medicine. The rhizomes contain numerous active components, of which Gastrodin (p-hydroxymethylphenyl-B-D-glucopyranoside) forms the basis of the traditional medicine Gastrodiae Rhizoma. Gastrodin is also found in other medicinal plants and has neuroprotective, antioxidant, and anti-inflammatory effects. Neuroinflammation plays a crucial role in neurodegeneration. Research indicates that consuming meals and drinks containing Gastrodiaelata can enhance cognitive functioning and memory in elderly patients. The mechanisms relevant to the problem have not been completely understood. PURPOSE: The aim was to examine the in vivo and in vitro anti-neuroinflammatory effects of Gastrodin. STUDY DESIGN: The neuroprotective effects of Gastrodin on the TLR4/TRAF6/NF-κB pathway and Stat3 phosphorylation in LPS-treated C57BL/6 mice and BV-2 cells were investigated. METHODS: 1. C57BL/6 mice were assigned to model, gastrodin, donepezil, and control groups (n = 10 per group). The Gastrodin group received 100 mg/kg/d for five days, and the Dopenezil group 1.3 mg/kg/d. A neuroinflammation model was established by administering intraperitoneal injections of 2 mg/kg LPS to all groups, excluding the control. To induce microglial activation in Gastrodin-treated mouse microglial BV-2 cells, 1 µg/ml LPS was introduced for 24 h Morris water mazes were utilized to evaluate learning and spatial memory. Expression and subcellular localization of TLR4/TRAF6/NF-κB axis-related proteins and p-Stat3, Iba-1, GFAP, iNOS, and CD206 were assessed by immunofluorescence, western blots, and ELISA. qRT-PCR was performed to determine and measure IL-1ß, TNF-α, cell migration, and phagocytosis. Overexpression of TRAF6 was induced by transfection, and the effect of Gastrodin on IL-1ß and p-NF-κB p65 levels was assessed. RESULTS: 1. In mice, gastrodin treatment mitigated LPS-induced deficits in learning and spatial memory, as well as reducing neuroinflammation in the hippocampus, expression of TLR4/TRAF6/NF-κB pathway proteins, activation of microglia and astrocytes, and phosphorylation of Stat3. 2. Gastrodin pretreatment improved LPS-induced inflammation in vitro, reducing expression of TLR4/TRAF6/NF-κB-associated proteins and p-Stat3, inducing microglial transformation from M1 to M2, and inhibiting migration and phagocytosis. Overexpression of TRAF6 inhibited the Gastrodin-induced effects. CONCLUSION: Gastrodin suppresses neuroinflammation and microglial activation by modifying the TLR4/TRAF6/NF-κB pathway and Stat3 phosphorylation.

The yin and yang of nuclear envelope breakdown through the activity of phosphatase holoenzyme PP2A-B55SUR-6.

Cell division is a highly regulated and guardedly orchestrated process including nuclear envelope breakdown (NEBD). A recent study from Kapoor, Adhikary, and Kotak identifies the symphonic role of a phosphatase holoenzyme in NEBD.

Phosphorylation-dependent deubiquitinase OTUD3 regulates YY1 stability and promotes colorectal cancer progression.

Yin Yang 1 (YY1) is a key transcription factor that has been implicated in the development of several malignancies. The stability of YY1 is regulated by the ubiquitin-proteasome system. The role of deubiquitinases (DUBs) and their impact on YY1 remain to be fully elucidated. In this study, we screened for ubiquitin-specific proteases that interact with YY1, and identified OTUD3 as a DUB for YY1. Over-expressed OTUD3 inhibited YY1 degradation, thereby increasing YY1 protein levels, whereas OTUD3 knockdown or knockout promoted YY1 degradation, thereby decreasing the proliferation of colorectal cancer (CRC). Furthermore, PLK1 mediates OTUD3 S326 phosphorylation, which further enhances OTUD3 binding and deubiquitination of YY1. In CRC tissues, elevated the expression level of OTUD3 and YY1 were significantly associated with poor prognostic outcomes. These findings suggest that the OTUD3-YY1 pathway has therapeutic potential in CRC, and OTUD3 plays a critical role in regulating YY1.

Corydaline alleviates Parkinson's disease by regulating autophagy and GSK-3ß phosphorylation.

BACKGROUND: Jitai tablet, a traditional Chinese medicine, has a neuroprotective effect on 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced Parkinson's disease (PD) mice. As one of the main active ingredients in the Jitai tablet, corydaline (Cory) has analgesic and anti-allergic effects, but it has not been studied in PD. Here, we investigated the role and mechanism of Cory in PD. METHODS: The PD model was induced by MPTP. Cell viability was measured by 3-(4, 5)-dimethylthiahiazo (-z-y1)-3, 5-di-phenytetrazoliumromide assay. The Pole test and traction test were performed to detect the behaviors of mice. The expression of tyrosine hydroxylase (Th) was detected by immunohistochemistry and Western blot. Immunofluorescence staining, monodansylcadaverine staining, and Western blot were conducted to assess autophagy. A lactic dehydrogenase release assay was used to detect cytotoxicity. Network pharmacology was used to screen the targets. RESULTS: There existed cytotoxicity when the concentration of Cory reached 40 µg/mL. Cory (not exceeding 20 µg/mL) could alleviate MPTP-induced cell damage. In vivo experiments indicated that Cory could improve the motor coordination of mice with PD. Besides, Cory could increase LC3-II/LC3-I levels both in vivo and in vitro. In addition, the Th levels reduced in the striatum and middle brain tissues of Parkinson's mice were recovered by Cory injection. We also found that Cory decreased the phosphorylation of glucogen synthase kinase-3 beta (GSK-3ß) at Tyr216 and increased the phosphorylation of GSK-3ß at Ser9 not only in primary neurons and SH-SY5Y cells but also in the striatum and middle brain tissues. Furthermore, Cory increased LC3-II/LC3-I levels and decreased p62 levels by regulating GSK-3ß. CONCLUSION: Cory enhanced autophagy, attenuated MPTP-induced cytotoxicity, and alleviated PD partly through the regulation of GSK-3ß phosphorylation.

Unveiling the role of host kinases at different steps of influenza A virus life cycle.

Influenza viruses remain a major public health concern causing contagious respiratory illnesses that result in around 290,000-650,000 global deaths every year. Their ability to constantly evolve through antigenic shifts and drifts leads to the emergence of newer strains and resistance to existing drugs and vaccines. To combat this, there is a critical need for novel antiviral drugs through the introduction of host-targeted therapeutics. Influenza viruses encode only 14 gene products that get extensively modified through phosphorylation by a diverse array of host kinases. Reversible phosphorylation at serine, threonine, or tyrosine residues dynamically regulates the structure, function, and subcellular localization of viral proteins at different stages of their life cycle. In addition, kinases influence a plethora of signaling pathways that also regulate virus propagation by modulating the host cell environment thus establishing a critical virus-host relationship that is indispensable for executing successful infection. This dependence on host kinases opens up exciting possibilities for developing kinase inhibitors as next-generation anti-influenza therapy. To fully capitalize on this potential, extensive mapping of the influenza virus-host kinase interaction network is essential. The key focus of this review is to outline the molecular mechanisms by which host kinases regulate different steps of the influenza A virus life cycle, starting from attachment-entry to assembly-budding. By assessing the contributions of different host kinases and their specific phosphorylation events during the virus life cycle, we aim to develop a holistic overview of the virus-host kinase interaction network that may shed light on potential targets for novel antiviral interventions.

B-cell lymphoma-2 phosphorylation at Ser70 site-related autophagy mediates puerarin-inhibited the apoptosis of MC3T3-E1 cells during osteoblastogenesis.

OBJECTIVE: To explore the relationship between autophagy and apoptosis regulated by puerarin during osteoblastogenesis. METHODS: In this study, the effects of puerarin on the autophagic activity and apoptosis level of osteoblast precursors (MC3T3-E1 cells) was observed. Subsequently, the roles of puerarin on B-cell lymphoma-2 (Bcl-2) phosphorylation at different sites in osteoblast precursors were observed. The effect of puerarin on the interaction between Bcl-2 and autophagy regulatory molecule or pro-apoptotic molecule was also investigated using Co-immunoprecipitation assays. In addition, the effect of puerarin on mitochondrial membrane potential of osteoblast precursors was also identified by mitochondrial membrane potential fluorescence probe assays. RESULTS: Our results showed that puerarin can promote the autophagic activity and apoptosis level of MC3T3-E1 cells. In addition, puerarin promoted Bcl-2 phosphorylation at Ser70 site, and the dissociation of Bcl-2-Beclin1 complex. Moreover, puerarin could enhance the binding of Bcl-2-Bcl-2-Associated X (Bax) complex in MC3T3-E1 cells. Furthermore, puerarin increased the mitochondrial membrane potential of MC3T3-E1 cells. CONCLUSIONS: Therefore, puerarin promotes Beclin1 into autophagy flux through Bcl-2 phosphorylation at Ser70, thereby enhancing autophagy of osteoblast precursors, which mediates its anti-apoptotic role during osteoblastogenesis. Furthermore, the dissociation of Bcl-2-Beclin1 complex is conducive to the binding of Bcl-2-Bax complex, which resists the apoptosis of osteoblast precursors viathe increased mitochondrial membrane potential.

Sinomenine ameliorates fibroblast-like synoviocytes dysfunction by promoting phosphorylation and nuclear translocation of CRMP2.

ETHNOPHARMACOLOGICAL RELEVANCE: Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by synovial inflammation and arthritic pain. Sinomenine (SIN), derived from the rhizome of Chinese medical herb Qing Teng (scientific name: Sinomenium acutum (Thunb.) Rehd. Et Wils), has a longstanding use in Chinese traditional medicine for treating rheumatoid arthritis. It has been shown to possess anti-inflammatory, analgesic, and immunosuppressive effects with minimal side-effects clinically. However, the mechanisms governing its effects in treatment of joint pathology, especially on fibroblast-like synoviocytes (FLSs) dysfunction, and arthritic pain remains unclear. AIM: This study aimed to investigate the effect and underlying mechanism of SIN on arthritic joint inflammation and joint FLSs dysfunctions. MATERIALS AND METHODS: Collagen-induced arthritis (CIA) was induced in rats and the therapeutic effects of SIN on joint pathology were evaluated histopathologically. Next, we conducted a series of experiments using LPS-induced FLSs, which were divided into five groups (Naïve, LPS, SIN 10, 20, 50 µg/ml). The expression of inflammatory factors was measured by qPCR and ELISA. The invasive ability of cells was detected by modified Transwell assay and qPCR. Transwell migration and cell scratch assays were used to assess the migration ability of cells. The distribution and content of relevant proteins were observed by immunofluorescence and laser confocal microscopy, as well as Western Blot and qPCR. FLSs were transfected with plasmids (CRMP2 T514A/D) to directly modulate the post-translational modification of CRMP2 protein and downstream effects on FLSs function was monitored. RESULTS: SIN alleviated joint inflammation in rats with CIA, as evidenced by improvement of synovial hyperplasia, inflammatory cell infiltration and cartilage damage, as well as inhibition of pro-inflammatory cytokines release from FLSs induced by LPS. In vitro studies revealed a concentration-dependent suppression of SIN on the invasion and migration of FLSs induced by LPS. In addition, SIN downregulated the expression of cellular CRMP2 that was induced by LPS in FLSs, but increased its phosphorylation at residue T514. Moreover, regulation of pCRMP2 T514 by plasmids transfection (CRMP2 T514A/D) significantly influenced the migration and invasion of FLSs. Finally, SIN promoted nuclear translocation of pCRMP2 T514 in FLSs. CONCLUSIONS: SIN may exert its anti-inflammatory and analgesic effects by modulating CRMP2 T514 phosphorylation and its nuclear translocation of FLSs, inhibiting pro-inflammatory cytokine release, and suppressing abnormal invasion and migration. Phosphorylation of CRMP2 at the T514 site in FLSs may present a new therapeutic target for treating inflammatory joint's destruction and arthritic pain in RA.

Tau Phosphorylation Patterns in the Rat Cerebral Cortex After Traumatic Brain Injury and Sodium Selenate Effects: An Epibios4rx Project 2 Study.

Sodium selenate (SS) activates protein phosphatase 2 (PP2A) and reduces phosphorylated tau (pTAU) and late post-traumatic seizures after lateral fluid percussion injury (LFPI). In EpiBioS4Rx Project 2, a multi-center international study for post-traumatic targets, biomarkers, and treatments, we tested the target relevance and modification by SS of pTAU forms and PP2A and in the LFPI model, at two sites: Einstein and Melbourne. In Experiment 1, adult male rats were assigned to LFPI and sham (both sites) and naïve controls (Einstein). Motor function was monitored by neuroscores. Brains were studied with immunohistochemistry (IHC), Western blots (WBs), or PP2A activity assay, from 2 days to 8 weeks post-operatively. In Experiment 2, LFPI rats received SS for 7 days (SS0.33: 0.33 mg/kg/day; SS1: 1 mg/kg/day, subcutaneously) or vehicle (Veh) post-LFPI and pTAU, PR55 expression, or PP2A activity were studied at 2 days and 1 week (on treatment), or 2 weeks (1 week off treatment). Plasma selenium and SS levels were measured. In Experiment 1 IHC, LFPI rats had higher cortical pTAU-Ser202/Thr205-immunoreactivity (AT8-ir) and pTAU-Ser199/202-ir at 2 days, and pTAU-Thr231-ir (AT180-ir) at 2 days, 2 weeks, and 8 weeks, ipsilaterally to LFPI, than controls. LFPI-2d rats also had higher AT8/total-TAU5-ir in cortical extracts ipsilateral to the lesion (WB). PP2A (PR55-ir) showed time- and region-dependent changes in IHC, but not in WB. PP2A activity was lower in LFPI-1wk than in sham rats. In Experiment 2, SS did not affect neuroscores or cellular AT8-ir, AT180-ir, or PR55-ir in IHC. In WB, total cortical AT8/total-TAU-ir was lower in SS0.33 and SS1 LFPI rats than in Veh rats (2 days, 1 week); total cortical PR55-ir (WB) and PP2A activity were higher in SS1 than Veh rats (2 days). SS dose dependently increased plasma selenium and SS levels. Concordant across-sites data confirm time and pTAU form-specific cortical increases ipsilateral to LFPI. The discordant SS effects may either suggest SS-induced reduction in the numbers of cells with increased pTAU-ir, need for longer treatment, or the involvement of other mechanisms of action.

Upregulation of tumor suppressor PIAS3 by Honokiol promotes tumor cell apoptosis via selective inhibition of STAT3 tyrosine 705 phosphorylation.

The natural product Honokiol exhibits robust antitumor activity against a range of cancers, and it has also received approval to undergo phase I clinical trial testing. We confrmed that honokiol can promote the apoptotic death of tumor cells through cell experiments. Then siRNA constructs specific for PIAS3, PIAS3 overexpression plasmid and the mutation of the STAT3 Tyr705 residue were used to confirm the mechanism of Honokiol-induced apoptosis. Finally, we confrmed that honokiol can promote PIAS3 upregulation, in turn suppressing STAT3 Tyr705 phosphorylation through the in vivo and in vitro experiments. Honokiol was ultimately found to reduce tumor cell viability by promoting apoptosis through a mechanism dependent on the ability of Honokiol to promote PIAS3 upregulation and the selective inhibition of p-STAT3 (Tyr705) without affecting p-STAT3 (Ser727) or p-STAT1 (Tyr701) levels. PIAS3 knockdown and overexpression in tumor cells altered STAT3 activation and associated DNA binding activity through the control of Tyr705 phosphorylation via PIAS3-STAT3 complex formation, ultimately shaping Honokiol-induced tumor cell apoptosis. Honokiol was also confirmed to significantly prolong the survival of mice bearing xenograft tumors in a PIAS3-dependent fashion. Together, these findings highlight a novel pathway through which Honokiol can promote PIAS3 upregulation, in turn suppressing STAT3 Tyr705 phosphorylation and promoting the apoptotic death of tumor cells.

Protopanaxatriol activates EGFR and HER2 to strengthen the molecules of skin protection in human keratinocytes.

BACKGROUND: Protopanaxatriol (PPT) is an important ginsenoside produced by ginseng, a tonic plant used in many areas. PPT has beneficial effects against many disease states including inflammation, diabetes, and cancer. However, PPT's protective effects on skin integrity have been rarely studied. Previously, we reported that PPT can maintain skin moisture through activation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) pathways. However, the cellular targets for enhancing skin moisturizing effects via PPT are still unknown. PURPOSE: We wanted to identify the upstream targets of PPT on upregulating moisturizing factor (HAS-2) expression. STUDY DESIGN: We investigated which upstream proteins can be directly stimulated by PPT to modulate NF-κB, MAPKs and other signaling cascades. Then, the targeted proteins were overexpressed to check the relationship with HAS-2. Next, the cellular thermal shift assay (CETSA) was conducted to check the relationship between targeted proteins and PPT. METHODS: A human keratinocyte HaCaT were employed to measure the levels of moisturizing factors and the signaling proteins activated by PPT. Transfection conditions were established with DNA constructs expressing epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) and their mutants prepared by site-directed mutagenesis. Further investigation on molecular mechanisms was conducted by RT-PCR, luciferase reporter gene assay, CETSA, or Western blot. RESULTS: We found that PPT can activate the phosphorylation of EGFR and HER2. These stimulations caused Src phosphorylation, which resulted in the activation of phosphoinositide 3-kinases (PI3K)/pyruvate dehydrogenase kinase 1 (PDK1)/protein kinase B (AKT)/NF-κB and MAPKs signaling cascades. Additionally, EGFR and HER2 activation resulted in phosphorylation of signal transducer and activator of transcription 3 (STAT3) and calcium/calmodulin-dependent protein kinase II (CaMKII). This induced the AMP-activated protein kinase alpha (AMPKα) signaling pathway. Additionally, PPT blocked peroxisome proliferator activated receptor gamma (PPARγ), which also contributed to the phosphorylation of Src. CONCLUSION: Overall, we first found that PPT offers excellent protection of the skin barrier and hydrogen supply in keratinocytes. Moreover, growth factor receptors such as EGFR and HER2 were revealed to be central enzymes to be directly targeted by PPT. These results suggest a potentially valuable role as a cosmetic ingredient.

High-dose ascorbic acid potentiates immune modulation through STAT1 phosphorylation inhibition and negative regulation of PD-L1 in experimental sepsis.

Sepsis is a complex, multifactorial syndrome characterized by a dysregulated host response to infection, leading to severe organ dysfunction and high mortality rates among critically ill patients. Hypovitaminosis C and vitamin C deficiency are frequently observed in septic patients, prompting interest in the potential therapeutic role of ascorbic acid. Although intravenous administration of ascorbic acid has been investigated in multiple clinical trials for sepsis treatment, the specific immunomodulatory mechanisms underlying its effects remain elusive. This study aimed to investigate the protective effects of high-dose ascorbic acid on experimental sepsis. Results show that intravenous administration of high-dose ascorbic acid (250 mg/kg) attenuated sepsis-induced organ dysfunctions in a cecal ligation and puncture (CLP)-induced septic mouse model. Ascorbic acid improved splenic cell apoptosis and increased the number of CD3+ T cells in septic mice induced by CLP. Furthermore, ascorbic acid downregulated PD-L1 expression in livers, reduced PD-1 expression in spleens, and inhibited the phosphorylation of STAT1 at Y701 in multiple organs of CLP-induced septic mice. The in vitro experiments also revealed that 800 µM ascorbic acid suppressed STAT1 phosphorylation and inhibited lipopolysaccharide (LPS) and IFN-γ-induced PD-L1 expression in macrophages. These findings suggest that ascorbic acid prevents sepsis-associated organ dysfunction through the p-STAT1/PD-L1 signaling pathway. Our study provides new insights into the potential therapeutic use of ascorbic acid in sepsis.

Effects of Whey Protein Combined with Amylopectin/Chromium on the Muscle Protein Synthesis and mTOR Phosphorylation in Exercised Rats.

This study aimed to examine the impact of varying doses of whey protein (WP) and amylopectin/chromium complex (ACr) supplementation on muscle protein synthesis (MPS), amino acid and insulin levels, and the rapamycin (mTOR) signaling pathways in exercised rats. A total of 72 rats were randomly divided into nine groups: (1) Exercise (Ex), (2) Ex + WPI to (5) Ex + WPIV with various oral doses of whey protein (0.465, 1.55, 2.33, and 3.1 g/kg) and (6) Ex + WPI + ACr to (9) Ex + WPIV + ACr with various doses of whey protein combined with 0.155 g/kg ACr. On the day of single-dose administration, the products were given by oral gavage after exercise. To measure the protein fractional synthesis rate (FSR), a bolus dose of deuterium-labeled phenylalanine was given, and its effects were evaluated 1 h after supplementation. Rats that received 3.1 g/kg of whey protein (WP) combined with ACr exhibited the most significant increase in muscle protein synthesis (MPS) compared to the Ex group (115.7%, p < 0.0001). In comparison to rats that received the same dose of WP alone, those given the combination of WP and ACr at the same dosage showed a 14.3% increase in MPS (p < 0.0001). Furthermore, the WP (3.1 g/kg) + ACr group exhibited the highest elevation in serum insulin levels when compared to the Ex group (111.9%, p < 0.0001). Among the different groups, the WP (2.33 g/kg) + ACr group demonstrated the greatest increase in mTOR levels (224.2%, p < 0.0001). Additionally, the combination of WP (2.33 g/kg) and ACr resulted in a 169.8% increase in 4E-BP1 levels (p < 0.0001), while S6K1 levels rose by 141.2% in the WP (2.33 g/kg) + ACr group (p < 0.0001). Overall, supplementation with various doses of WP combined with ACr increased MPS and enhanced the mTOR signaling pathway compared to WP alone and the Ex group.