Gallic Acid Alleviates Cognitive Impairment by Promoting Neurogenesis via the GSK3ß-Nrf2 Signaling Pathway in an APP/PS1 Mouse Model.

Background: Neuronal loss occurs early and is recognized as a hallmark of Alzheimer's disease (AD). Promoting neurogenesis is an effective treatment strategy for neurodegenerative diseases. Traditional Chinese herbal medicines serve as a rich pharmaceutical source for modulating hippocampal neurogenesis. Objective: Gallic acid (GA), a phenolic acid extracted from herbs, possesses anti-inflammatory and antioxidant properties. Therefore, we aimed to explore whether GA can promote neurogenesis and alleviate AD symptoms. Methods: Memory in mice was assessed using the Morris water maze, and protein levels were examined via western blotting and immunohistochemistry. GA's binding site in the promoter region of transcription regulator nuclear factor erythroid 2-related factor 2 (Nrf2) was calculated using AutoDock Vina and confirmed by a dual luciferase reporter assay. Results: We found that GA improved spatial memory by promoting neurogenesis in the hippocampal dentate gyrus zone. It also improved synaptic plasticity, reduced tau phosphorylation and amyloid-ß concentration, and increased levels of synaptic proteins in APP/PS1 mice. Furthermore, GA inhibited the activity of glycogen synthase kinase-3ß (GSK-3ß). Bioinformatics tools revealed that GA interacts with several amino acid sites on GSK-3ß. Overexpression of GSK-3ß was observed to block the protective effects of GA against AD-like symptoms, while GA promoted neurogenesis via the GSK-3ß-Nrf2 signaling pathway in APP/PS1 mice. Conclusions: Based on our collective findings, we hypothesize that GA is a potential pharmaceutical agent for alleviating the pathological symptoms of AD.

Beneficial effect of electroacupuncture on the distribution of foreign substances in the brain of rats developing depression-like behavior.

We used low and high molecular weight fluorescence tracers to investigate the entry of foreign solutes into the brain parenchyma and their exit from it by the glymphatic system, during experimentally induced depressive-like behavior in rats. The tail suspension test (TST), as an acute stressor, is known to induce such a type of behavior, considered to model the human major depressive disorder (MDD). Electroacupuncture (EAP) relieves both depressive-like behavior in rodents and the symptoms of MDD in humans. Here we report that 180 min after the intracisternal injection of the low molecular weight tracer Fluorescein-5-Isothiocianate Conjugated Dextran (FITC-d3), a 15-min duration TST tended to increase the control fluorescence in the brain of rats. Both EAP and sham EAP decreased the fluorescence of FITC-d3 in comparison with the TST, but not the control value. In addition, EAP and sham EAP counteracted the effects of TST. The high molecular weight tracer Ovalbumin Alexa Fluor 555 Conjugate (OA-45) failed to enter the brain parenchyma and accumulated at more superficial sites; however, EAP or sham EAP modified the distribution of fluorescence under TST application in a similar manner as that observed during the use of FITC-d3. It is concluded that EAP is possibly a valid treatment to slow down the entry of foreign solutes into the brain; in view of the comparable effects of EAP on FITC-d3 and OA-45 distribution, EAP seems to act before FITC-d3 passes the astroglial aquaporin-4 water channels, which are a critical constituent of the glymphatic system.

Harmine suppresses breast cancer cell migration and invasion by regulating TAZ-mediated epithelial-mesenchymal transition.

Breast cancer is a highly lethal disease due to cancer metastasis. Harmine (HM), a ß-carboline alkaloid, is present in various medicinal plants. Our previous study demonstrated that HM suppresses cell proliferation and migration by regulating TAZ in breast cancer cells and accelerates apoptosis. Epithelial-mesenchymal transition (EMT) plays an important role in the development of breast cancer by inducing the characteristics of cancer stem cells, cancer metastasis and recurrence. Overexpression of TAZ was shown to mediate EMT in breast cancer cells. We aimed to investigate whether HM inhibits EMT and metastasis of breast cancer cells by targeting TAZ. In this study, the cells treated with HM or with downregulated expression of TAZ showed an increase in epithelial markers and decrease in mesenchymal markers in breast cancer cells. Consistently, the breast cancer cells treated with HM or with downregulated expression of TAZ showed suppressed migration and proliferation. Moreover, TAZ overexpression reversed EMT and metastasis induced by HM in breast cancer cells. Thus, HM suppresses EMT and metastasis and invasion by targeting TAZ in breast cancer cells. HM can be used as an anticancer drug for breast cancer treatment and chemoprevention.

Emodin targeting the colonic metabolism via PPARγ alleviates UC by inhibiting facultative anaerobe.

BACKGROUND: Emodin is an active ingredient of traditional Chinese medicine Rheum palmatum L. and Polygonum cuspidatum, which possesses anti-inflammatory and intestinal mucosal protection effects. Our previous study found that emodin significantly alleviated ulcerative colitis induced by sodium dextran sulfate (DSS). In this study, we found the underlying mechanism of emodin on ulcerative colitis (UC). PURPOSE: We aimed to further explore the mechanism of emodin in the treatment of ulcerative colitis from the perspective of metabolism and intestinal flora. METHODS: Ulcerative colitis was induced by 3% sodium dextran sulfate (DSS) on mice, and the mice were respectively treated with mesalazine, rosiglitazone, emodin, and emodin combined with GW9662 (PPARγ inhibitor) simultaneously. Weight changes, the disease activity index (DAI), colonic length, and pathologic changes in colon were used to evaluate the efficacy of emodin. LC-MS/MS was performed for metabolomics analysis of colon. In addition, intestinal flora was assessed using 16S rDNA sequencing. A vector-based short hairpin RNA (shRNA) method was used to silence PPARγ gene expression in Caco-2 cells. RESULTS: Emodin binds to the active site of PPARγ protein and forms hydrogen bond interaction with ARG288 and CYS285 amino acids. Furthermore, Emodin significantly promotes the protein expression of PPARγ, while inhibiting iNOS and NF-kB p65 in UC mice, however, this effect is hardly shown when it is combined with GW9662 (the inhibitor of PPARγ). Meanwhile, emodin suppresses the expression of iNOS in Caco-2 cells induced with IFNγ and IL-22, but has no effect on its expression in shPPARγ-Caco-2 cells. In addition, through activating PPARγ signal pathway, emodin is capable of regulating colonic metabolism including oxidative phosphorylation and citrulline metabolism and effecting luminal availability of oxygen and nitrate. This promotes the recovery of anoxic environment of colon epithelial cells, which strains the growth and expansion of Enterobacteriaceae. CONCLUSION: The mechanism of Emodin in the treatment of ulcerative colitis relies on its regulation of PPARγ signal pathway, which could modulate colonic metabolism and restore intestinal homeostasis.

Effect of Huangqin decoction on regulating intestinal flora in colitis mice characterized as inhibition of the NOD2-dependent pathway.

CONTEXT: Chinese herb Huangqin decoction (HQD) can regulate intestinal flora in ulcerative colitis (UC) mice. OBJECTIVE: Our study clarifies the mechanism of HQD in regulating the intestinal flora of UC mice. MATERIALS AND METHODS: Male C57BL/6 mice were randomly divided into six groups: Control, Model (3% DSS), Sulfasalazine (500 mg/kg), HQD-L (250 mg/kg), HQD-M (500 mg/kg), and HQD-H (1000 mg/kg) groups. Measurement of body weight, colon length, DAI, and haematoxylin-eosin staining were conducted. FISH and 16S rDNA detected colonic bacterial infiltration and intestinal flora changes. The expression of RegIIIγ and PRRs (NOD2, TLR5, TLR4) were detected by FCM and WB, respectively. In addition, WB, qPCR, or IHC were used to detect the expression of NOD2, MyD88, RIP2, and NF-κB p65 in the colon. ELISA was used to determine cytokines. RESULTS: Compared with the model group (DAI score, 2.38 ± 0.05; histological score, 4.08 ± 0.54), HQD treatment significantly reduced the DAI score (L, 2.16 ± 0.09; M, 1.45 ± 0.05; H, 1.18 ± 0.05) and histological score (L, 3.16 ± 0.82; M, 2.50 ± 0.81; H, 1.51 ± 0.76); restored the weight, the colonic length (p < 0.05). 16S rDNA identification showed HQD regulated the balance of intestinal flora. Moreover, HQD suppressed the expression of RegIIIγ (p < 0.05) and prevented colonic bacterial infiltration. Furthermore, WB results showed NOD2, and TLR4 were inhibited by HQD, especially NOD2 (p < 0.01). The data of WB, qPCR, and IHC demonstrated that the NOD2-dependent pathway was inhibited by HQD (p < 0.01). DISCUSSION AND CONCLUSIONS: HQD (1000 mg/kg) regulates the intestinal flora of colitis mice, mainly characterized as inhibition of the NOD2-dependent pathway. These results indicate that HQD has potential.

Employing ATP as a New Adjuvant Promotes the Induction of Robust Antitumor Cellular Immunity by a PLGA Nanoparticle Vaccine.

Tumor vaccines based on synthetic human papillomavirus (HPV) oncoprotein E7 and/or E6 peptides have shown encouraging results in preclinical model studies and human clinical trials. However, the clinical efficacy may be limited by the disadvantages of vulnerability to enzymatic degradation and low immunogenicity of peptides. To further improve the potency of vaccine, we developed a poly(lactide-co-glycolide)-acid (PLGA) nanoparticle, which encapsulated the antigenic peptide HPV16 E744-62, and used adenosine triphosphate (ATP), one of the most important intracellular metabolites and an endogenous extracellular danger signal for the immune system, as a new adjuvant component. The results showed that PLGA nanoparticles increased the in vivo stability, lymph node accumulation, and dendritic cell (DC) uptake of the E7 peptide; in addition, ATP further increased the migration, nanoparticle uptake, and maturation of DCs. Preventive immunization with ATP-adjuvanted nanoparticles completely abolished the growth of TC-1 tumors in mice and produced long-lasting immunity against tumor rechallenge. When tumors were fully established, therapeutic immunization with ATP-adjuvanted nanoparticles still significantly inhibited tumor progression. Mechanistically, ATP-adjuvanted nanoparticles significantly improved the systemic generation of antitumor effector cells, boosted the local functional status of these cells in tumors, and suppressed the generation and tumor infiltration of immunosuppressive Treg cells and myeloid-derived suppressor cells. These findings indicate that ATP is an effective vaccine adjuvant and that nanoparticles adjuvanted with ATP were able to elicit robust antitumor cellular immunity, which may provide a promising therapeutic vaccine candidate for the treatment of clinical malignancies, such as cervical cancer.

Purinergic signaling as a basis of acupuncture-induced analgesia.

This review summarizes experimental evidence indicating that purinergic mechanisms are causally involved in acupuncture (AP)-induced analgesia. Electroacupuncture (EAP) and manual AP release at pain-relevant acupoints ATP which may activate purinergic P2X receptors (Rs) especially of the P2X3 type situated at local sensory nerve endings (peripheral terminals of dorsal root ganglion [DRG] neurons); the central processes of these neurons are thought to inhibit via collaterals of ascending dorsal horn spinal cord neurons, pain-relevant pathways projecting to higher centers of the brain. In addition, during AP/EAP non-neuronal P2X4 and/or P2X7Rs localized at microglial cells of the CNS become activated at the spinal or supraspinal levels. In consequence, these microglia secrete bioactive compounds such as growth factors, cytokines, chemokines, reactive oxygen, and nitrogen species, which modulate the ascending neuronal pathways conducting painful stimuli. Alternatively, ATP released at acupoints by AP/EAP may be enzymatically degraded to adenosine, stimulating in loco presynaptic A1Rs exerting an inhibitory influence on the primary afferent fibers (the above mentioned pain-sensing peripheral terminals of DRG neurons) which thereby fail to conduct action potentials to the spinal cord dorsal horn. The net effect of the stimulation of P2X3, P2X4, P2X7, and A1Rs by the AP/EAP-induced release of ATP/adenosine at certain acupoints will be analgesia.

Harmine induces anticancer activity in breast cancer cells via targeting TAZ.

Harmine (HM) is a ß­carboline alkaloid found in multiple medicinal plants. It has been used in folk medicine for anticancer therapy; however, the molecular mechanism of HM on human breast cancer remains unclear. Transcriptional co­activator with PDZ­binding motif (TAZ), also known as WW domain­containing transcription regulator 1, serves an important role in the carcinogenesis and progression of breast cancer. The aim of the present study was to elucidate the potential anticancer activity and mechanism of HM in breast cancer, in vitro and in vivo. Cell proliferation was measured using a CCK­8 assay, apoptotic activity was detected by flow cytometry and DAPI staining, and cell migration was examined using a wound healing assay. The expression of proteins, including extracellular signal­regulate kinase (Erk), phosphorylated (p­) Erk, protein kinase B (Akt), p­Akt, B­cell lymphoma 2 (Bcl­2) and Bcl­2­associated X protein (Bax), were determined by western blotting. The mRNA expression of TAZ was detected using reverse transcription­quantitative polymerase chain reaction analysis. The expression of proteins in mouse tumor tissues were examined by immunohistochemistry. HM significantly suppressed cellular proliferation and migration, promoted apoptosis in vitro and inhibited tumor growth in vivo. In addition, HM significantly decreased the expression of TAZ, p­Erk, p­Akt and Bcl­2, but increased that of Bax. The overexpression of TAZ in breast cancer cells inhibited the antitumor effect of HM. In conclusion, HM was found to induce apoptosis and prevent the proliferation and migration of human breast cancer cell lines, possibly via the downregulation of TAZ.

An outbreak of Mycoplasma pneumoniae caused by a macrolide-resistant isolate in a nursery school in China.

Eighteen out of 45 children were reported to have a respiratory illness during an outbreak at a temporary dormitory in a nursery school in China in 2011. To study the outbreak and to determine the risk factors for infection, an epidemiological investigation was performed. A standardized questionnaire was completed for a total of 45 children with the help of their guardians and parents. In addition, acute- and convalescent-phase serum samples and throat swabs from the children were taken for laboratory diagnosis. The diagnosis of a Mycoplasma-like illness was based on the following clinical criteria. The criteria were onset of illness after 31 May 2011, characterized by a cough, fever(>37.5 °C), or at least 3 of the following symptoms: fever, sore throat, cough or expectoration, and runny or stuffy nose. PCR-restriction fragment length polymorphism (PCR-RFLP), determination of MICs, and sequencing were performed to determine the genotype, antibiotic resistance, and sequence polymorphisms of the isolated strains, respectively. The paired sera revealed that 15 patients were infected with Mycoplasma pneumoniae. Epidemiology confirmed that this was a point source outbreak, characterized by a short incubation period, a high secondary attack rate, and a long period of hospitalization. PCR-RFLP analysis revealed that the 12 isolated strains of M. pneumoniae shared the same subtype P1 gene, and 23S rRNA sequence analysis showed that these strains harbored two macrolide-resistant gene-related point mutations at position 2063 and 2617. In this outbreak, the major risk factor was the distance between the bed of the first patient and the beds of close contacts (beds less than three meters apart). The strains isolated in this study were found to harbor two point mutations conferring macrolide resistance, indicating the importance of pathogen and drug resistance surveillance systems.