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Journal of Neurogenetics Jun 2024The neurogenetics and vision community recently mourned William L. Pak, PhD, whose pioneering work spearheaded the genetic, electrophysiological, and molecular bases of...
Personal essay of a rookie's journey with Bill Pak and his legacy: tales and perspectives on PI-PLC, NorpA and cyclophilin, NinaA - William L. Pak, PhD., 1932-2023: in memoriam.
The neurogenetics and vision community recently mourned William L. Pak, PhD, whose pioneering work spearheaded the genetic, electrophysiological, and molecular bases of biological processes underpinning vision. This essay provides a historical background to the daunting challenges and personal experiences that carved the path to seminal findings. It also reflects on the intellectual framework, mentoring philosophy, and inspirational legacy of Bill Pak's research. An emphasis and perspectives are placed on the discoveries and implications to date of the phosphatidylinositol-specific phospholipase C (P IP LC), NorpA, and the cyclophilin, NinaA of the fruit fly, Drosophila melanogaster, and their respective mammalian homologues, P I-P LCβ4, and cyclophilin-related protein, Ran-binding protein 2 (Ranbp2) in critical biological processes and diseases of photoreceptors and other neurons.
PubMed: 38913811
DOI: 10.1080/01677063.2024.2366455 -
PeerJ 2024(Thunb.) Makino, a well-known edible and medicinal plant, has anti-aging properties and is used to treataging-associated conditions such as diabetes, metabolic...
BACKGROUND
(Thunb.) Makino, a well-known edible and medicinal plant, has anti-aging properties and is used to treataging-associated conditions such as diabetes, metabolic syndrome, and cardiovascular diseases. Gypenosides (GYPs) are the primary constituents of . Increasing evidence indicates that GYPs are effective at preserving mitochondrial homeostasis and preventing heart failure (HF). This study aimed to uncover the cardioprotective mechanisms of GYPs related to mitochondrial regulation.
METHODS
The bioactive components in GYPs and the potential targets in treating HF were obtained and screened using the network pharmacology approach, followed by drug-disease target prediction and enrichment analyses. The pharmacological effects of GYPs in cardioprotection, mitochondrial function, mitochondrial quality control, and underlying mechanisms were further investigated in Doxorubicin (Dox)-stimulated H9c2 cardiomyocytes.
RESULTS
A total of 88 bioactive compounds of GYPs and their respective 71 drug-disease targets were identified. The hub targets covered MAPK, EGFR, PI3KCA, and Mcl-1. Enrichment analysis revealed that the pathways primarily contained PI3K/Akt, MAPK, and FoxO signalings, as well as calcium regulation, protein phosphorylation, apoptosis, and mitophagy process. In Dox-stimulated H9c2 rat cardiomyocytes, pretreatment with GYPs increased cell viability, enhanced cellular ATP content, restored basal oxygen consumption rate (OCR), and improved mitochondrial membrane potential (MMP). Furthermore, GYPs improved PINK1/parkin-mediated mitophagy without influencing mitochondrial fission/fusion proteins and the autophagic LC3 levels. Mechanistically, the phosphorylation of PI3K, Akt, GSK-3β, and the protein level of Mcl-1 was upregulated by GYP treatment.
CONCLUSION
Our findings reveal that GYPs exert cardioprotective effects by rescuing the defective mitophagy, and PI3K/Akt/GSK-3/Mcl-1 signaling is potentially involved in this process.
Topics: Gynostemma; Mitophagy; Glycogen Synthase Kinase 3 beta; Signal Transduction; Myeloid Cell Leukemia Sequence 1 Protein; Proto-Oncogene Proteins c-akt; Cardiotonic Agents; Plant Extracts; Phosphatidylinositol 3-Kinases; Animals; Rats; Myocytes, Cardiac; Cell Line
PubMed: 38912051
DOI: 10.7717/peerj.17538 -
International Journal of Nanomedicine 2024Endometriosis (EM) is an estrogen-dependent benign gynecologic disease affecting approximately 10% of reproductive-age women with a high recurrence rate, but lacks...
INTRODUCTION
Endometriosis (EM) is an estrogen-dependent benign gynecologic disease affecting approximately 10% of reproductive-age women with a high recurrence rate, but lacks reliable biomarkers. No previous studies have investigated the possible use of extracellular vesicle (EV)-associated micro RNAs (miRNAs) from menstrual blood (MB) as candidate diagnostic or prognostic markers of EM.
METHODS
Specimens were obtained from endometriosis and non-endometriosis patients at the International Peace Maternity and Child Health Hospital in Shanghai. Microarray was used to screen differentially expressed miRNAs among peritoneal fluid (PF), fallopian tube fluid (FF), and MB. Dual-luciferase reporter gene assay was carried out to verify the relationship between miR-4443 and ACSS2. Cell proliferation and Transwell invasion assays were performed in vitro after intervention on miR-4443 and ACSS2 in hEM15A human endometrial stromal cells and primary human endometrial stromal cells (hESCs). Spearman correlation analysis, receiver operating characteristic (ROC) curve analysis, and survival analysis were applied to clinical data, including severity of symptoms and relapse of EM among EM patients.
RESULTS
EV-associated miR-4443 was abundant in MB of endometriosis patients. ACSS2 knockdown and miR-4443 overexpression promoted cell proliferation and migration via the PI3K/AKT pathway. miR-4443 levels in MB-EVs were positively correlated with the degree of dyspareunia (r=0.64; P<0.0001) and dysmenorrhea (r=0.42; P<0.01) in the endometriosis group. ROC curve analyses showed an area under the curve (AUC) of 0.741 (95% CI 0.624-0.858; P<0.05) for miR-4443 and an AUC of 0.929 (95% CI 0.880-0.978; P<0.05) for the combination of miR-4443 and dysmenorrhea.
CONCLUSION
MB-derived EV-associated miR-4443 might participate in endometriosis development, thus providing a new candidate biomarker for the noninvasive prediction of endometriosis recurrence.
Topics: Humans; Endometriosis; Female; MicroRNAs; Extracellular Vesicles; Proto-Oncogene Proteins c-akt; Adult; Cell Proliferation; Phosphatidylinositol 3-Kinases; Disease Progression; Cell Movement; Signal Transduction; Cell Line; Endometrium
PubMed: 38911502
DOI: 10.2147/IJN.S456594 -
RSC Medicinal Chemistry Jun 2024[This corrects the article DOI: 10.1039/D3MD00630A.].
[This corrects the article DOI: 10.1039/D3MD00630A.].
PubMed: 38911159
DOI: 10.1039/d4md90022g -
TH Open : Companion Journal To... Apr 2024Agonist-induced platelet activation, with the integrin αIIbβ3 conformational change, is required for fibrinogen binding. This is considered reversible under...
Agonist-induced platelet activation, with the integrin αIIbβ3 conformational change, is required for fibrinogen binding. This is considered reversible under specific conditions, allowing a second phase of platelet aggregation. The signaling pathways that differentiate between a permanent or transient activation state of platelets are poorly elucidated. To explore platelet signaling mechanisms induced by the collagen receptor glycoprotein VI (GPVI) or by protease-activated receptors (PAR) for thrombin that regulate time-dependent αIIbβ3 activation. Platelets were activated with collagen-related peptide (CRP, stimulating GPVI), thrombin receptor-activating peptides, or thrombin (stimulating PAR1 and/or 4). Integrin αIIbβ3 activation and P-selectin expression was assessed by two-color flow cytometry. Signaling pathway inhibitors were applied before or after agonist addition. Reversibility of platelet spreading was studied by microscopy. Platelet pretreatment with pharmacological inhibitors decreased GPVI- and PAR-induced integrin αIIbβ3 activation and P-selectin expression in the target order of protein kinase C (PKC) > glycogen synthase kinase 3 > β-arrestin > phosphatidylinositol-3-kinase. Posttreatment revealed secondary αIIbβ3 inactivation (not P-selectin expression), in the same order, but this reversibility was confined to CRP and PAR1 agonist. Combined inhibition of conventional and novel PKC isoforms was most effective for integrin closure. Pre- and posttreatment with ticagrelor, blocking the P2Y adenosine diphosphate (ADP) receptor, enhanced αIIbβ3 inactivation. Spreading assays showed that PKC or P2Y inhibition provoked a partial conversion from filopodia to a more discoid platelet shape. PKC and autocrine ADP signaling contribute to persistent integrin αIIbβ3 activation in the order of PAR1/GPVI > PAR4 stimulation and hence to stabilized platelet aggregation. These findings are relevant for optimization of effective antiplatelet treatment.
PubMed: 38911141
DOI: 10.1055/s-0044-1786987 -
Chinese Journal of Integrative Medicine Jun 2024To explore the neuroprotective effects and mechanism of Tanreqing Injection (TRQ) on treating ischemic stroke based on network pharmacology and in vivo experimental...
OBJECTIVE
To explore the neuroprotective effects and mechanism of Tanreqing Injection (TRQ) on treating ischemic stroke based on network pharmacology and in vivo experimental validation.
METHODS
The chemical compounds of TRQ were retrieved based on published data, with targets retrieved from PubChem, Therapeutic Target Database and DrugBank. Network visualization and analysis were performed using Cytoscape, with protein-protein interaction networks derived from the STRING database. Enrichment analysis was performed using Kyoto Encyclopedia of Genes Genomes pathway and Gene Ontology analysis. In in vivo experiments, the middle cerebral artery occlusion (MCAO) model was used. Infarct volume was determined by 2,3,5-triphenyltetrazolium hydrochloride staining and protein expressions were analyzed by Western blot. Molecular docking was performed to predict ligand-receptor interactions.
RESULTS
We screened 81 chemical compounds in TRQ and retrieved their therapeutic targets. Of the targets, 116 were therapeutic targets for stroke. The enrichment analysis showed that the apelin signaling pathway was a key pathway for ischemic stroke. Furthermore, in in vivo experiment we found that administering with intraperitoneal injection of 2.5 mL/kg TRQ every 6 h could significantly reduce the infarct volume of MCAO rats (P<0.05). In addition, protein levels of the apelin receptor (APJ)/phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway were increased by TRQ (P<0.05). In addition, 41 chemical compounds in TRQ could bind to APJ.
CONCLUSIONS
The neuroprotective effect of TRQ may be related to the APJ/PI3K/AKT signaling pathway. However, further studies are needed to confirm the findings.
PubMed: 38910191
DOI: 10.1007/s11655-024-3910-6 -
The Journal of Reproduction and... Jun 2024Understanding how stress hormones induce apoptosis in oviductal epithelial cells (OECs) and mural granulosa cells (MGCs) can reveal the mechanisms by which female stress...
Understanding how stress hormones induce apoptosis in oviductal epithelial cells (OECs) and mural granulosa cells (MGCs) can reveal the mechanisms by which female stress impairs embryonic development and oocyte competence. A recent study showed that tissue plasminogen activator (tPA) ameliorates corticosterone-induced apoptosis in MGCs and OECs by acting on its receptors low-density lipoprotein receptor-related protein 1 (LRP1) and Annexin A2 (ANXA2), respectively. However, whether tPA is involved in corticotropin-releasing hormone (CRH)-induced apoptosis and whether it uses the same or different receptors to inhibit apoptosis induced by different hormones in the same cell type remains unknown. This study showed that CRH triggered apoptosis in both OECs and MGCs and significantly downregulated tPA expression. Moreover, tPA inhibits CRH-induced apoptosis by acting on ANXA2 in both OECs and MGCs. While ANXA2 inhibits apoptosis via phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling, LRP1 reduces apoptosis via mitogen-activated protein kinase (MAPK) signaling. Thus, tPA used the same receptor to inhibit CRH-induced apoptosis in both OECs and MGCs, however used different receptors to inhibit corticosterone-induced apoptosis in MGCs and OECs. These data helps understand the mechanism by which female stress impairs embryo/oocyte competence and proapoptotic factors trigger apoptosis in different cell types.
PubMed: 38910127
DOI: 10.1262/jrd.2024-028 -
Cellular Signalling Jun 2024In breast cancer, over one third of all patients harbor a somatic mutation in the PIK3CA gene, encoding the p110α catalytic subunit of the phosphatidylinositol 3-kinase...
BACKGROUND
In breast cancer, over one third of all patients harbor a somatic mutation in the PIK3CA gene, encoding the p110α catalytic subunit of the phosphatidylinositol 3-kinase (PI3K) in their tumor cells. Circulating tumor cells (CTCs) are cells shed from the primary tumor into the blood stream. Recently, the long-term stable breast cancer CTC-ITB-01 cell line with tumorigenic and metastatic capacity was established from liquid biopsy derived cells. The oncogenic hotspot PIK3CA mutation H1047R (kinase domain) was detected in the primary tumor, CTCs and metastasis of the same patient. Other PIK3CA mutations located within the C2 domain (E418K and E453K) were detected in the CTCs and the vaginal metastasis but not in the primary tumor. The goal of our study was to functionally characterize the impact of the rare E418K and E453K mutations within the C2 domain that were not detected in the primary tumor.
METHODS
PIK3CA mutations E418K, E453K, H1047R were generated by site-directed mutagenesis and stably overexpressed in breast cancer cells by lentiviral transduction. Subsequent signaling pathway activation was examined by western blot analysis. The impact of PIK3CA mutations on biological processes was studied by live cell imaging using the Incucyte Zoom system. Structural modeling was conducted in Pymol. The membrane localization of the mutants was evaluated by separating the cytosolic and membrane fraction using ultracentrifugation. Drug susceptibility of CTC-ITB-01 cells was analyzed by live cell imaging.
RESULTS
Western blot analysis of human MDA-MB-231, MCF-7 and T47D breast cancer cells stably overexpressing either the PIK3CA wildtype (WT) or one of the E418K, E453K or H1047R mutants revealed a significant increase in AKT phosphorylation in both C2 mutants (E418K and E453K) and the kinase domain mutant H1047R. Functional analysis showed a significantly increased proliferation of MDA-MB-231 cells overexpressing the E453K and H1047R mutants. Migration was increased in all cells overexpressing WT and each of the mutants. Interestingly, invasion and chemotaxis were only enhanced in the MDA-MB-231 cells overexpressing the C2 domain mutants, i.e. E418K and E453K. In addition, membrane localization of the two C2 domain mutants was increased. Structural modeling of the E453K mutation suggests a disruption of the interaction between the negative regulatory domain of the p85α subunit and the p110α catalytic subunit as a potential mechanism leading to the observed activation of PI3K/AKT/mTOR signaling. Dual targeting of AKT/mTOR pathway by MK2206 and RAD001 leads to very strong synergistic effects (IC MK2206: 148 nM, IC RAD001: 15 nM) with respect to proliferation in the CTC-ITB-01 line through apoptosis induction.
CONCLUSIONS
Our results demonstrate that PIK3CA C2 domain mutations activate PI3K downstream AKT signaling and can increase proliferation, migration and invasion after stable lentiviral transduction. Although both investigated mutations - E418K and E453K - are located within the C2 domain, a different molecular mechanism can be proposed. The PIK3CA mutated CTC-ITB-01 shows a high susceptibility against dual inhibition of AKT/mTOR. Further studies are required to fully elucidate the oncogenic potential of rare PIK3CA mutations.
PubMed: 38909932
DOI: 10.1016/j.cellsig.2024.111270 -
International Immunopharmacology Jun 2024Cisplatin (CDDP) is commonly employed as an antineoplastic agent, but its use is significantly limited by the occurrence of dose-dependent nephrotoxicity, the detailed...
AIMS
Cisplatin (CDDP) is commonly employed as an antineoplastic agent, but its use is significantly limited by the occurrence of dose-dependent nephrotoxicity, the detailed mechanisms of which remain unclear. This research is aimed to explore the molecular mechanisms of Piracetam (PIR)'s protective effects on nephrotoxicity resulting from CDDP exposure and to elucidate the mechanisms responsible for these effects.
MAIN METHODS
PIR was given in dosages of 100 and 300 mg/kg body weight for a duration of 15 days; concurrently, on the last day, a single 10 mg/kg dose of CDDP was delivered via intraperitoneal injection. Forty-eight hours post-CDDP injection, the animals were sacrificed to assess nephrotoxicity. Blood samples and renal tissues were taken for biochemical and histopathological investigations. Serum creatinine and blood urea nitrogen (BUN) were measured. AMP-activated protein kinase (AMPK), caspase-9 and nuclear factor kappa b p65 (NF-κB p65) were assessed by immunohistochemistry method. Enzyme-linked immunosorbent assay (ELISA) analysis was employed to determine cytochrome c (Cyt. c), Bcl-2-associated X-protein (BAX), caspase-3, nuclear factor erythroid 2-related factor 2 (Nrf2), Heme oxygenase-1 (HO-1), superoxide dismutase (SOD), tumor necrosis factor alpha (TNF-α), myeloperoxidase (MPO), and interleukin-1β (IL-1β) levels in renal tissue homogenates. The mRNA levels of tumor protein P53 (TP53), phosphatidylinositol-3 kinase (PI3K), protein kinase B (Akt), p38 mitogen-activated protein kinase (p38 MAPK), extracellular signal-regulated kinases (ERK), and c-Jun N-terminal kinases (JNK) were tested by quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, histopathological evaluations of the renal tissues and the binding affinity of PIR to AMPK by molecular docking were also performed.
KEY FINDINGS
Pre-treatment with PIR enhanced renal function markers such as urea and creatinine, mitigated histological damage, and diminished inflammatory cell presence in renal tubules. PIR demonstrated antioxidant effects by reestablishing the equilibrium between pro-oxidants and antioxidants such as MPO, HO-1, Nrf2, as well as SOD. Furthermore, PIR inhibited the inflammatory pathways through the MAPK/NF-κB pathway. Additionally, PIR counteracted the CDDP-induced decline in PI3K/Akt activity and hindered caspase-dependent apoptotic processes.
SIGNIFICANCE
In summary, PIR appears to be an effective therapeutic strategy for reducing CDDP-induced nephrotoxicity, attributed to its antioxidant, anti-inflammatory, and antiapoptotic mechanisms. Consequently, PIR may serve as a complementary treatment alongside CDDP to alleviate nephrotoxicity associated with CDDP.
PubMed: 38909496
DOI: 10.1016/j.intimp.2024.112511 -
BMC Women's Health Jun 2024Insulin resistance (IR) induces hyperinsulinemia, which activates downstream signaling pathways such as the phosphatidylinositol-3-kinase/protein kinase B (PI3K/AKT)...
BACKGROUND
Insulin resistance (IR) induces hyperinsulinemia, which activates downstream signaling pathways such as the phosphatidylinositol-3-kinase/protein kinase B (PI3K/AKT) pathway, ultimately leading to abnormal proliferation and apoptosis of endometrial cells. This is thought to be a key pathogenic mechanism underlying the development of endometrial polyps (EP). This study aims to investigate the relationship between IR and the development of EP, the expression levels of downstream signaling molecules, including PI3K and AKT, and related laboratory parameters were examined.
METHODS
A total of 100 patients who visited the gynecology outpatient clinic of Zhongda Hospital affiliated with Southeast University from May 2021 to March 2023 and were diagnosed with abnormal endometrial echoes by vaginal ultrasound and underwent hysteroscopic diagnostic curettage were enrolled in this study. General data and relevant hematological indicators were compared, and intraoperative specimens were obtained for pathological examination. Possible factors influencing the development of endometrial polyps were analyzed using Pearson correlation analysis and logistic regression analysis.
RESULTS
In terms of body mass index, waist circumference, fasting insulin, insulin resistance index, serum total testosterone, and free testosterone index, women of childbearing age in the endometrial polyp group had higher values than those in the non-polyp group, while sex hormone-binding globulin in the endometrial polyp group was lower than that in the non-polyp group, and the differences were statistically significant (P < 0.05). The expression scores and mRNA expression levels of PI3K and AKT proteins were higher in the EP group than in the non-EP group (p < 0.05). Pearson correlation analysis showed a positive correlation between HOMA-IR and the expression scores of PI3K and AKT proteins (p < 0.01).
CONCLUSIONS
Insulin resistance and abnormal activation of the phosphatidylinositol 3-kinase/protein kinase B signaling pathway may be potential pathogenic mechanisms for the development of endometrial polyps.
Topics: Humans; Female; Insulin Resistance; Polyps; Proto-Oncogene Proteins c-akt; Adult; Phosphatidylinositol 3-Kinases; Middle Aged; Uterine Diseases; Body Mass Index; Signal Transduction; Endometrium; Sex Hormone-Binding Globulin; Testosterone; Insulin
PubMed: 38909214
DOI: 10.1186/s12905-024-03218-5