Quercetin Limits Tumor Immune Escape through PDK1/CD47 Axis in Melanoma.

Quercetin (3,3[Formula: see text],4[Formula: see text],5,7-pentahydroxyflavone) is a bioactive plant-derived flavonoid, abundant in fruits and vegetables, that can effectively inhibit the growth of many types of tumors without toxicity. Nevertheless, the effect of quercetin on melanoma immunology has yet to be determined. This study aimed to investigate the role and mechanism of the antitumor immunity action of quercetin in melanoma through both in vivo and in vitro methods. Our research revealed that quercetin has the ability to boost antitumor immunity by modulating the tumor immune microenvironment through increasing the percentages of M1 macrophages, CD8[Formula: see text] T lymphocytes, and CD4[Formula: see text] T lymphocytes and promoting the secretion of IL-2 and IFN-[Formula: see text] from CD8[Formula: see text] T cells, consequently suppressing the growth of melanoma. Furthermore, we revealed that quercetin can inhibit cell proliferation and migration of B16 cells in a dose-dependent manner. In addition, down-regulating PDK1 can inhibit the mRNA and protein expression levels of CD47. In the rescue experiment, we overexpressed PDK1 and found that the protein and mRNA expression levels of CD47 increased correspondingly, while the addition of quercetin reversed this effect. Moreover, quercetin could stimulate the proliferation and enhance the function of CD8[Formula: see text] T cells. Therefore, our results identified a novel mechanism through which CD47 is regulated by quercetin to promote phagocytosis, and elucidated the regulation of quercetin on macrophages and CD8[Formula: see text] T cells in the tumor immune microenvironment. The use of quercetin as a therapeutic drug holds potential benefits for immunotherapy, enhancing the efficacy of existing treatments for melanoma.

Insilico design of an allosteric modulator targeting the protein-protein interaction site of 3 Phosphoinositide dependent Kinase-1: design, synthesis and biological activity.

The signalling pathways in human cells mostly rely on protein-protein interactions (PPI) for their function. Such a PPI site in 3 Phosphoinositide dependent Kinase-1 (PDK1) is targeted to design the small molecule modulators. Based on the hotspot residues in its PPI site, a pharmacophore with seven different features was developed and screened against 2.9 million lead like compounds in Zinc database. A phthalazine derivative was identified as a potent allosteric inhibitor through virtual screening, molecular docking and 100 ns dynamics simulations. The modified hit possessed hydrogen bonds with Lys115, Arg131, Thr148, Glu150 as well as pi-pi stacking interactions with Phe157 which are the key residues in the PIF pocket of PDK1. Comparison between the free energy profiles by metadynamics simulation with the presence and absence of the modified ligand (MH) in the binding pocket indicates that the binding of MH enhances the hinge motion making PDK1 to adopt open conformation also and stabilizes the fluctuation of the end-to-end distance in αB helix of PDK1. The modified hit compound was synthesized, characterized and found to be cytotoxic to cancerous cells that are rich in PDK1 expression. These results propose that MH can serve as a new scaffold template for the design of novel drugs targeting PDK1 as well as promising allosteric regulator of PDK1 targeting its protein-protein interface. Supplementary Information: The online version contains supplementary material available at 10.1007/s40203-023-00160-6.

[Effect of Liangfang Wenjing Decoction on expression of key glycolytic enzymes in uterus and ovaries of rats with coagulating cold and blood stasis syndrome].

This study aimed to investigate the relationship between coagulating cold and blood stasis syndrome and glycolysis, and observe the intervention effect of Liangfang Wenjing Decoction(LFWJD) on the expression of key glycolytic enzymes in the uterus and ovaries of rats with coagulating cold and blood stasis. The rat model of coagulating cold and blood stasis syndrome was established by ice-water bath. After modeling, the quantitative scoring of symptoms were performed, and according to the scoring results, the rats were randomly divided into a model group and LFWJD low-, medium-and high-dose groups(4.7, 9.4, 18.8 g·kg~(-1)·d~(-1)), with 10 in each group. Another 10 rats were selected as the blank group. After 4 weeks of continuous administration by gavage, the quantitative scoring of symptoms was repeated. Laser speckle flowgraphy was used to detect the changes of microcirculation in the ears and uterus of rats in each group. Hematoxylin-eosin(HE) staining was used to observe the pathological morphology of uterus and ovaries of rats in each group. The mRNA and protein expressions of pyruvate dehydrogenase kinase 1(PDK1), hexokinase 2(HK2) and lactate dehydrogenase A(LDHA) in the uterus and ovaries of rats were examined by real-time quantitative polymerase chain reaction(RT-qPCR) and Western blot, respectively. The rats in the model group showed signs of coagulating cold and blood stasis syndrome, such as curl-up, less movement, thickened veins under the tongue, and reduced blood perfusion in the microcirculation of the ears and uterus, and HE staining revealed a thinning of the endometrium with disorganized arrangement of epithelial cells and a decrease in the number of ovarian follicles. Compared with the model group, the treatment groups had alleviated coagulating cold and blood stasis, which was manifested as red tongue, reduced nail swelling, no blood stasis at the tail end as well as increased blood perfusion of the microcirculation in the ears and uterus(P<0.05 or P<0.01). Among the groups, the LFWJD medium-and high-dose groups had the most significant improvement in coagulating cold and blood stasis, with neatly arranged columnar epithelial cells in uterus, and the number of ovarian follicles was higher than that in the model group, especially mature follicles. The mRNA and protein expressions of PDK1, HK2, LDHA in uterus and ovaries were up-regulated in the model group(P<0.05 or P<0.01), while down-regulated in LFWJD medium-and high-dose groups(P<0.05 or P<0.01). The LFWJD low-dose group presented a decrease in the mRNA expressions of PDK1, HK2 and LDHA in uterus and ovaries as well as in the protein expressions of HK2 and LDHA in uterus and HK2 and PDK1 in ovaries(P<0.05 or P<0.01). The therapeutic mechanism of LFWJD against coagulating cold and blood stasis syndrome is related to the down-regulation of key glycolytic enzymes PDK1, HK2 and LDHA, and the inhibition of glycolytic activities in uterus and ovaries.

Aristolone in Nardostachys jatamansi DC. induces mesenteric vasodilation and ameliorates hypertension via activation of the KATP channel and PDK1-Akt-eNOS pathway.

BACKGROUND: Nardostachys jatamansi DC. is a common medicinal herb used to treat cardiovascular diseases, particularly hypertension. Previously, our lab characterized the chemical compounds of N. jatamansi. However, the bioactive compounds of N. jatamansi and their mechanisms of action on blood pressure and blood vessels are unknown. PURPOSE: The vasorelaxant effects of the methanolic extract (MeOH ext.) of the roots and rhizomes of N. jatamansi, its main compounds, and their underlying mode of action, were investigated. METHODS: The main compounds of N. jatamansi were isolated and identified using UHPLC-TOF MS. The antihypertensive effect of N. jatamansi extracts and (-)-aristolone were determined using spontaneously hypertensive rats. The extracts, fractions, and compounds were also evaluated for their vasorelaxant effects on U46619 contractile responses in isolated thoracic aortic and mesenteric arterial rings. The endothelial-dependent relaxation, as well as the regulatory pathways and targets of (-)-aristolone, were studied in-vitro and ex-vivo. Molecular docking and biophysical characterization (Surface plasmon resonance) studies were utilized to investigate the molecular interaction between (-)-aristolone and the target protein. RESULTS: MeOH ext. (200 mg/kg) reduces the systolic and diastolic blood pressure in spontaneously hypertensive rats. MeOH ext. and its ethyl acetate fraction (EtOAc Fr.), but not the H2O fraction, had a significant relaxing effect on the thoracic aorta. (-)-aristolone and kanshone H from EtOAc Fr. induced vasorelaxation of the thoracic aorta and mesenteric artery. In human umbilical vein endothelial cells, (-)-aristolone treatment upregulated phosphorylation of Akt (T308) and eNOS. Molecular docking and surface plasmon resonance experiments revealed an interaction between (-)-aristolone and phosphoinositide-dependent protein kinase 1 (PDK1), an upstream protein kinase that phosphorylates Akt at T308. Treatment with PDK1 inhibitor PHT-427 and eNOS inhibitor L-NAME consistently inhibited (-)-aristolone-induced vasorelaxation. In addition, KATP channel inhibitor glibenclamide dramatically inhibited the vasorelaxant effects of (-)-aristolone and kanshone H in the endothelium-denuded thoracic aorta. Finally, (-)-aristolone lowers hypertensive rats' systolic and diastolic blood pressure. CONCLUSIONS: The extracts of N. jatamansi promote vasorelaxation and alleviate hypertension. The essential chemicals responsible for producing vasorelaxation effects are (-)-aristolone and kanshone H, which activate the PDK1-Akt-eNOS-NO relaxing pathway and stimulate the opening of the KATP channel. These findings point to N. jatamansi and aristolone as possible antihypertensive agents.

Crosstalk of LncRNA HOTAIR and SP1-mediated repression of PDK1 contributes to ß-Elemene-inhibited proliferation of hepatocellular carcinoma cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Hepatocellular carcinoma (HCC) is a liver malignancy which lacks effective treatment and has a poor prognosis. ß-Elemene refers to a natural Curcuma wenyujin-derived single molecular entity, which exhibits various biological activities, and is especially well-known for it's antitumor properties. AIM OF THE RESEARCH: LncRNA HOTAIR, SP1, and PDK1 have displayed oncogenic roles in many tumors, participating in the initiation and progression of cancers by mediating multiple signaling pathways. However, there are only a few reports about their roles and mutual relationship in the growth of HCC cells. Therefore, this study aimed to investigate the expression of LncRNA HOTAIR, SP1, and PDK1 and their interaction with ß-Elemene in HCC cells. MATERIALS AND METHODS: MTT, a Colony formation assay, and flow cytometry were employed to evaluate the growth of HCC and LO2 cells under ß-Elemene. LncRNA HOTAIR, SP1 and PDK1 plasmids were transfected into HCC cells by a transient transfection assay, and the expression and interaction of LncRNA HOTAIR, SP1 and PDK1 were assessed via qRT-PCR and western blotting. RESULTS: ß-Elemene suppressed HCC cell growth through the downregulation of LncRNA HOTAIR, SP1 and PDK1. The results demonstrated a reciprocal interaction among LncRNA HOTAIR, SP1 and PDK1. Exogenous overexpression LncRNA HOTAIR or SP1 eliminated the suppressive effects of ß-Elemene on them, and both of which regulated PDK1 expression in HCC cells. Additionally, exogenously overexpressed SP1 or LncRNA HOTAIR prevented ß-Elemene inhibition of the protein-level expression of PDK1, whereas overexpressing PDK1 had no effect on SP1, though it still weakened the inhibition of cell growth and LncRNA HOTAIR expression by ß-Elemene. CONCLUSION: ß-Elemene suppresses HCC cell proliferation via through the regulation of LncRNA HOTAIR, SP1, PDK1 and their interaction.

Suppression of phosphoinositide 3-kinase/phosphoinositide-dependent kinase-1/serum and glucocorticoid-induced protein kinase pathway.

In the current study, the pivotal roles of serum and glucocorticoid-induced protein kinase (SGK1) and NF-kB related signalings known as prognostic biomarkers in cervical cancers were explored in the antitumor effect of a ginseng saponin metabolite compound K (CK) in HeLa and SiHa cervical cancer cells. CK exerted significant cytotoxicity, induced sub-G1 accumulation, and attenuated the expression of proPoly (ADP-ribose) polymerase (pro-PARP) and Pro-cysteine aspartyl-specific protease (pro-caspase3) in HeLa cells more than in SiHa cells. CK inhibited phosphorylation of SGK1 and its upstream genes, phosphoinositide 3-kinases (PI3K), and phosphoinositide-dependent kinase-1 (PDK1) in HeLa cells. In addition, CK suppressed the phosphorylation of SGK1, NF-κB, and inhibitor of kappa B (IκB) and also NF-κB target genes such as X-linked inhibitor of apoptosis protein and B-cell lymphoma 2 (Bcl-2) in HeLa cells. Notably, Immunoprecipitation revealed that SGK1 binds to PI3K or PDK1 and also CK disturbed the binding between SGK1 and PI3K or PDK1 in HeLa cells. Furthermore, PI3K inhibitor LY294002 decreased expression of PI3K, p-PDK1, p-SGK1, and pro-caspase3 and SGK1 inhibitor GSK650394 also reduced expression of NF-κB and pro-caspase3 just like CK in HeLa cells. Overall, these findings suggest that CK induces apoptosis via suppression of PI3K/PDK1/SGK1 and NF-κB signaling axis.

Yin Yang 1-induced LINC00667 up-regulates pyruvate dehydrogenase kinase 1 to promote proliferation, migration and invasion of cholangiocarcinoma cells by sponging miR-200c-3p.

Cholangiocarcinoma (CCA) is one of the most aggressive and lethal malignancies. Long noncoding RNAs (lncRNAs) are being found to play crucial roles in CCA progression. This work aims to investigate the roles of long intergenic non-protein coding RNA 667 (LINC00667) in progression of CCA. RT-qPCR and western blot were applied to detect gene expression. Clinical correlation and survival were analyzed by statistical methods. Overexpression and RNA interference approaches were used to investigate the effects of LINC00667 on CCA cells. Tumor xenograft assay was performed to detect the function of LINC00667 in vivo. Transcriptional regulation and competing endogenous RNA (ceRNA) mechanism were predicted via bioinformatics analysis. ChIP, luciferase reporter, and Ago2 RIP assays further confirmed the predicted results. Our data indicated that LINC00667 was highly expressed in CCA tissues and cells, and transcription factor Yin Yang 1 (YY1) induced LINC00667 expression in CCA cells. Up-regulated LINC00667 was significantly associated with lymph node metastasis, advanced TNM stage, and poor prognosis. Knockdown of LINC00667 suppressed the proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) of CCA cells, while overexpression of LINC00667 acquired opposite effects. Moreover, knockdown of LINC00667 inhibited tumor growth in vivo. In addition, LINC00667 was demonstrated to function as a ceRNA for miR-200c-3p, and then LINC00667 up-regulated pyruvate dehydrogenase kinase 1 (PDK1) to promote CCA development by inhibiting miR-200c-3p. These findings identified a pivotal role of LINC00667 in tumorigenesis and development of CCA. Targeting the YY1/LINC00667/miR-200c-3p/PDK1 axis may provide a new therapeutic strategy for CCA treatment.

Archidendron lucidum Exerts Anti-Inflammatory Effects by Targeting PDK1 in the NF-κB Pathway.

Pharmacological activities of some Leguminosae family members were reported. Pharmacological activities of Archidendron lucidum, a Leguminosae family member have never been explored. Therefore, this study investigated anti-inflammatory effects of an Archidendron lucidum methanol extract (Al-ME). In this study, anti-inflammatory effects of Al-ME were investigated in LPS-stimulated RAW264.7 cells and HCl/EtOH-induced gastritis mice by MTT assay, nitric oxide (NO) production assay, semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), luciferase reporter assay, and Western blotting. High-performance liquid chromatography (HPLC) analysis identified ethnopharmacological compounds in Al-ME. Al-ME inhibited NO production without cytotoxicity in peritoneal macrophages and RAW264.7 cells stimulated with LPS or Pam3CSK4. Al-ME downregulated mRNA expression of inflammatory genes (inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2)) and pro-inflammatory cytokines (tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and IL-6). Al-ME exerted anti-inflammatory activity in LPS-stimulated RAW264.7 cells by inhibiting nuclear factor-kappa B (NF-κB) signaling pathway. HPLC analysis identified quercetin, luteolin, and kaempferol as major anti-inflammatory components in Al-ME. Al-ME ameliorated HCl/EtOH-induced gastritis symptoms in mice by suppressing iNOS and IL-6 mRNA expressions and IκBα phosphorylation. Therefore, these results suggest that Al-ME exhibited anti-inflammatory activity by targeting NF-κB signaling pathway, implying that Al-ME could be potent anti-inflammatory medications to prevent and treat inflammatory diseases.

Disturbed Yin-Yang balance: stress increases the susceptibility to primary and recurrent infections of herpes simplex virus type 1.

Herpes simplex virus type 1 (HSV-1), a neurotropic herpes virus, is able to establish a lifelong latent infection in the human host. Following primary replication in mucosal epithelial cells, the virus can enter sensory neurons innervating peripheral tissues via nerve termini. The viral genome is then transported to the nucleus where it can be maintained without producing infectious progeny, and thus latency is established in the cell. Yin-Yang balance is an essential concept in traditional Chinese medicine (TCM) theory. Yin represents stable and inhibitory factors, and Yang represents the active and aggressive factors. When the organism is exposed to stress, especially psychological stress caused by emotional stimulation, the Yin-Yang balance is disturbed and the virus can re-engage in productive replication, resulting in recurrent diseases. Therefore, a better understanding of the stress-induced susceptibility to HSV-1 primary infection and reactivation is needed and will provide helpful insights into the effective control and treatment of HSV-1. Here we reviewed the recent advances in the studies of HSV-1 susceptibility, latency and reactivation. We included mechanisms involved in primary infection and the regulation of latency and described how stress-induced changes increase the susceptibility to primary and recurrent infections.

An Integrated Network, RNA Sequencing, and Experiment Pharmacology Approach Reveals the Active Component, Potential Target, and Mechanism of Gelsemium elegans in the Treatment of Colorectal Cancer.

In this study, a combination of network pharmacology, bioinformatics analysis, molecular docking and transcriptomics was used to investigate the active ingredient and potential target of Gelsemium elegans in the treatment of colorectal cancer. Koumine was screened as the active component by targeting PDK1 through network pharmacology and reverse docking. RNA-Seq, enrichment analysis and validation experiment were then further employed to reveal koumine might function in inhibiting Akt/mTOR/HK2 pathway to regulate cell glycolysis and detachment of HK2 from mitochondria and VDAC-1 to activate cell apoptosis both in vitro and in vivo. In the present study, we provide a systematical approach for the identification of effective ingredient and potential target of herbal medicine. Our results have important implication for the intensive study of koumine as novel anticancer agents for colorectal cancer and could be supportive in its further structural modification.

Polyphyllin I induces autophagy and cell cycle arrest via inhibiting PDK1/Akt/mTOR signal and downregulating cyclin B1 in human gastric carcinoma HGC-27 cells.

Paris polyphylla. is a traditional medicinal herb that has long been used to prevent cancer in many Asian countries. Polyphyllin I (PPI), an important bioactive constituent of Paris polyphylla, has been found to exhibit a wide variety of anticancer activities in many types of cancer cells. However, the effects of PPI on human gastric carcinoma cells and its mechanism of action remain unclear. In this study, we examined the effective anti-gastric carcinoma activity of PPI and its underlying mechanism of action in HGC-27 cells. In vitro, sub-micromolar concentrations of PPI inhibited HGC-27 cell proliferation with an IC50 of 0.34 ± 0.06 µM after a 72-h treatment. In vivo, 3 mg/kg PPI significantly inhibited proliferation of HGC-27 tumor cells, with a 78.8% inhibition rate compared to paclitaxel, and demonstrated higher safety. Analysis of MDC and mGFP-LC3 fluorescence, Western blotting and flow cytometry indicated that PPI induced cell cycle arrest in HGC-27 cells by promoting the conversion of LC3-I to LC3-II and by downregulating cyclin B1. Furthermore, Western blotting showed that PPI inhibited the autophagy-regulating PDK1/Akt/mTOR signaling pathway in vitro and in vivo. In addition, immunohistochemistry and TUNEL staining revealed that PPI decreased Ki67 expression and increased the percentage of apoptotic cells in HGC-27 xenograft tumors. These data indicate that PPI is an PDK1/Akt/mTOR signaling inhibitor and of therapeutic relevance for gastric cancer treatment and that the rhizome of Paris polyphylla deserves further clinical investigation as an alternative therapy for gastric cancer.

Iridoids from Valeriana jatamansi induce autophagy-associated cell death via the PDK1/Akt/mTOR pathway in HCT116 human colorectal carcinoma cells.

Chlorovaltrates U-W (1-3), three previously undescribed iridoids, together with four known analogues were isolated from the roots of Valeriana jatamansi. Their structures were elucidated by means of spectroscopic analyses (HRESIMS, NMR). The cytotoxicity of all isolates was evaluated. Compounds 5-7 exhibited selective cytotoxicity against HCT116 cells, with IC50 values of 9.3, 1.7 and 2.2 µM, respectively. The preliminary mechanistic study revealed that, the cytotoxicity effect of 6 was attributed to Akt/mTOR activation blockade via inhibition of PDK1 phosphorylation. Meanwhile, compound 6 could induce autophagosome formation in HCT116 cells via suppressing its downstream Akt/mTOR. These findings show that compound 6 could be of great importance to the development of anti-colon cancer agents.

Mycetia cauliflora methanol extract exerts anti-inflammatory activity by directly targeting PDK1 in the NF-κB pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Mycetia cauliflora Reinw. (Rubiaceae) has been used as a traditional remedy to ameliorate clinical signs of inflammatory diseases, including pain, inflammation, ulcers, and wounds. Among the Mycetia subfamilies, the molecular and cellular mechanisms of Mycetia longifolia (Rubiaceae) have been studied. However, those of Mycetia cauliflora are not clearly understood. Comprehensive investigation of this plant is necessary to evaluate its potential for ethnopharmacological use. MATERIALS: and methods: The activities of Mycetia cauliflora methanol extract (Mc-ME) on the secretion of inflammatory mediators, the mRNA expression of proinflammatory cytokines, and identification of its molecular targets were elucidated using lipopolysaccharide (LPS)-induced macrophage-like cells. Moreover, the suppressive actions of Mc-ME were examined in an LPS-induced peritonitis mouse model. RESULTS: At nontoxic concentrations, Mc-ME downregulated the release of nitric oxide (NO), the mRNA expression of inducible nitric oxide synthase (iNOS), and the mRNA expression of interleukin (IL)-1ß from LPS-activated RAW264.7 cells. This extract also inhibited the nuclear translocation of p65 and p50 and the phosphorylation of IκBα, IKK, and AKT. Western blot analysis and in vitro kinase assays confirmed that phosphoinositide-dependent kinase-1 (PDK1) is the direct immunopharmacological target of Mc-ME effect. In addition, Mc-ME significantly reduced inflammatory signs in an animal model of acute peritonitis. These effects were associated with decreased NO production and decreased AKT phosphorylation. CONCLUSION: Our results suggest that Mc-ME displays anti-inflammatory actions in LPS-treated macrophage-like cells and in an animal model of acute inflammatory disease. These actions are preferentially managed by targeting PDK1 in the nuclear factor (NF)-κB signaling pathway.

PDK1 in NF-κB signaling is a target of Xanthium strumarium methanolic extract-mediated anti-inflammatory activities.

ETHNOPHARMACOLOGICAL RELEVANCE: Xanthium strumarium L. (Asteraceae) has traditionally been used to treat bacterial infections, nasal sinusitis, urticaria, arthritis, chronic bronchitis and rhinitis, allergic rhinitis, edema, lumbago, and other ailments. However, the molecular mechanisms by which this plant exerts its anti-inflammatory effects are poorly characterized. Here we studied the immunopharmacological activities of the methanolic extract of the aerial parts of this plant (Xs-ME) and validated its pharmacological targets. MATERIALS AND METHODS: To evaluate the anti-inflammatory activity of Xs-ME, we employed lipopolysaccharide (LPS)-treated macrophages and an HCl/EtOH-induced mouse model of gastritis. We also used HPLC to identify the potentially active anti-inflammatory components of this extract. The molecular mechanisms of its anti-inflammatory activity were studied by kinase assays, reporter gene assays, immunoprecipitation analysis, and overexpression of target enzymes. RESULTS: The production of nitric oxide (NO) and prostaglandin E2 (PGE2) were both suppressed by Xs-ME. Moreover, orally administered Xs-ME ameliorated HCl/EtOH-induced gastric lesions. Furthermore, this extract downregulated the expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 and reduced the nuclear levels of NF-κB. Signaling events upstream of NF-κB translocation, such as phosphorylation of AKT and the formation of PDK1-AKT signaling complexes, were also inhibited by Xs-ME. Moreover, Xs-ME suppressed the enzymatic activity of PDK1. Additionally, PDK1-induced luciferase activity and Akt phosphorylation were both inhibited by Xs-ME. We also identified the polyphenol resveratrol as a likely active anti-inflammatory component in Xs-ME that targets PDK1. CONCLUSION: Xs-ME exerts anti-inflammatory activity in vitro and in vivo by inhibiting PDK1 kinase activity and blocking signaling to its downstream transcription factor, NF-κB.

DHEA supplementation in ovariectomized rats reduces impaired glucose-stimulated insulin secretion induced by a high-fat diet.

Dehydroepiandrosterone (DHEA) and the dehydroepiandrosterone sulfate (DHEA-S) are steroids produced mainly by the adrenal cortex. There is evidence from both human and animal models suggesting beneficial effects of these steroids for obesity, diabetes mellitus, hypertension, and osteoporosis, conditions associated with the post-menopausal period. Accordingly, we hypothesized that DHEA supplementation in ovariectomized (OVX) female rats fed a high-fat diet would maintain glucose-induced insulin secretion (GSIS) and pancreatic islet function. OVX resulted in a 30% enlargement of the pancreatic islets area compared to the control rats, which was accompanied by a 50% reduction in the phosphorylation of AKT protein in the pancreatic islets. However, a short-term high-fat diet induced insulin resistance, accompanied by impaired GSIS in isolated pancreatic islets. These effects were reversed by DHEA treatment, with improved insulin sensitivity to levels similar to the control group, and with increased serine phosphorylation of the AKT protein. These data confirm the protective effect of DHEA on the endocrine pancreas in a situation of diet-induced overweight and low estrogen concentrations, a phenotype similar to that of the post-menopausal period.

Huang-Lian-Jie-Du-Decotion induced protective autophagy against the injury of cerebral ischemia/reperfusion via MAPK-mTOR signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Huang-Lian-Jie-Du-Decotion (HLJDD, Hwangryun-Hae-Dok-Decotion in Japan), an ancient antipyretic and detoxifying traditional Chinese medicine formula, was reported to have protective effect on ischemic stroke. AIM OF THE RESEARCH: To investigate the therapeutic effect of HLJDD on ischemic stroke and explore its mode of action. MATERIAL AND METHODS: A model of ischemic stroke in the rat was established after transient middle cerebral artery occlusion (MCAO) followed by reperfusion. Rats were assigned randomly to groups of control, sham, transient ischemia/reperfusion (I/R), and three treatment groups by HLJDD at 2.5, 5.0, 10.0mg/kg. The neurological deficit, the cerebral infarct size, morphology abnormality, biochemical parameters were examined, and the levels of relevant proteins were determined by immunoblotting analysis to evaluate the protective effects of HLJDD on ischemic stroke and explore the underlying mechanism. RESULTS: Compared with I/R group, HLJDD significantly ameliorated neurological deficit and histopathology changes, decreased infarct area, and restored the levels of biochemical indicators including nitric oxide (NO), malondialdehyde (MDA), glutathione (GSH), glutathione disulfide (GSSG), total superoxide dismutase (T-SOD), Cu/Zn-SOD, Mn-SOD and glutathione peroxidase (GSH-PX). HLJDD also notably elevated the levels of microtubule-associated protein 1 light chain 3 (LC3), Beclin-1, and other autophagy related genes (Atgs), promoted the activation of extracellular signal-regulated kinases (ERK), protein kinase B (Akt), 3-phosphoinositide-dependent kinase (PDK1), and inhibited the activation of mammalian target of rapamycin (mTOR), c-Jun N-terminal protein kinases (JNK), p38, phosphatase and tensin homolog (PTEN). CONCLUSION: HLJDD showed neuroprotective effects on ischemic stroke, at least in part to the induced protective autophagy via the regulation of mitogen-activated protein kinase (MAPK) signals. This Akt-independent protective autophagy is favorable in the treatment of stroke, avoiding unfavorable side-effects associated with the inactivation of Akt. The efficacy of HLJDD on ischemic stroke and its safety warranted by its long-term clinical use in traditional Chinese medicine favored further study to develop HLJDD as an effective therapeutic agent to treat ischemic stroke.