Microtubule remodelling as a driving force of axon guidance and pruning

The establishment of neuronal connectivity relies on the microtubule (MT) cytoskeleton, which provides mechanical support, roads for axonal transport and mediates signalling events. Fine-tuned spatiotemporal regulation of MT functions by tubulin post-translational modifications and MT-associated proteins is critical for the coarse wiring and subsequent refinement of neuronal connectivity. The defective regulation of these processes causes a wide range of neurodevelopmental disorders associated with connectivity defects. This review focuses on recent studies unravelling how MT composition, post-translational modifications and associated proteins influence MT functions in axon guidance and/or pruning to build functional neuronal circuits. We here summarise experimental evidence supporting the key role of this network as a driving force for growth cone steering and branch-specific axon elimination. We further provide a global overview of the MT-interactors that tune developing axon behaviours, with a special emphasis on their emerging versatility in the regulation of MT dynamics/structure. Recent studies establishing the key and highly selective role of the tubulin code in the regulation of MT functions in axon pathfinding are also reported. Finally, our review highlights the emerging molecular links between these MT regulation processes and guidance signals that wire the nervous system.

The Complement System in Kidney Transplantation

Kidney transplantation is the therapy of choice for patients who suffer from end-stage renal diseases. Despite improvements in surgical techniques and immunosuppressive treatments, long-term graft survival remains a challenge. A large body of evidence documented that the complement cascade, a part of the innate immune system, plays a crucial role in the deleterious inflammatory reactions that occur during the transplantation process, such as brain or cardiac death of the donor and ischaemia/reperfusion injury. In addition, the complement system also modulates the responses of T cells and B cells to alloantigens, thus playing a crucial role in cellular as well as humoral responses to the allograft, which lead to damage to the transplanted kidney. Since several drugs that are capable of inhibiting complement activation at various stages of the complement cascade are emerging and being developed, we will discuss how these novel therapies could have potential applications in ameliorating outcomes in kidney transplantations by preventing the deleterious effects of ischaemia/reperfusion injury, modulating the adaptive immune response, and treating antibody-mediated rejection.

Drug Repurposing and Systems Biology approaches of Enzastaurin can target potential biomarkers and critical pathways in Colorectal Cancer

Colorectal cancer (CRC) is a severe health concern that results from a cocktail of genetic, epigenetic, and environmental abnormalities. Because it is the second most lethal malignancy in the world and the third-most common malignant tumor, but the treatment is unavailable. The goal of the current study was to use bioinformatics and systems biology techniques to determine the pharmacological mechanism underlying putative important genes and linked pathways in early-onset CRC. Computer-aided methods were used to uncover similar biological targets and signaling pathways associated with CRC, along with bioinformatics and network pharmacology techniques to assess the effects of enzastaurin on CRC. The KEGG and gene ontology (GO) pathway analysis revealed several significant pathways including in positive regulation of protein phosphorylation, negative regulation of the apoptotic process, nucleus, nucleoplasm, protein tyrosine kinase activity, PI3K-Akt signaling pathway, pathways in cancer, focal adhesion, HIF-1 signaling pathway, and Rap1 signaling pathway. Later, the hub protein module identified from the protein-protein interactions (PPIs) network, molecular docking and molecular dynamics simulation represented that enzastaurin showed strong binding interaction with two hub proteins including CASP3 (-8.6 kcal/mol), and MCL1 (-8.6 kcal/mol), which were strongly implicated in CRC management than other the five hub proteins. Moreover, the pharmacokinetic features of enzastaurin revealed that it is an effective therapeutic agent with minimal adverse effects. Enzastaurin may inhibit the potential biological targets that are thought to be responsible for the advancement of CRC and this study suggests a potential novel therapeutic target for CRC.

The pseudokinase NRBP1 activates Rac1/Cdc42 via P-Rex1 to drive oncogenic signalling in triple-negative breast cancer

We have determined that expression of the pseudokinase NRBP1 positively associates with poor prognosis in triple negative breast cancer (TNBC) and is required for efficient migration, invasion and proliferation of TNBC cells in culture as well as growth of TNBC orthotopic xenografts and experimental metastasis. Application of BioID/MS profiling identified P-Rex1, a known guanine nucleotide exchange factor for Rac1, as a NRBP1 binding partner. Importantly, NRBP1 overexpression enhanced levels of GTP-bound Rac1 and Cdc42 in a P-Rex1-dependent manner, while NRBP1 knockdown reduced their activation. In addition, NRBP1 associated with P-Rex1, Rac1 and Cdc42, suggesting a scaffolding function for this pseudokinase. NRBP1-mediated promotion of cell migration and invasion was P-Rex1-dependent, while constitutively-active Rac1 rescued the effect of NRBP1 knockdown on cell proliferation and invasion. Generation of reactive oxygen species via a NRBP1/P-Rex1 pathway was implicated in these oncogenic roles of NRBP1. Overall, these findings define a new function for NRBP1 and a novel oncogenic signalling pathway in TNBC that may be amenable to therapeutic intervention.

NRF2 signaling pathway: A comprehensive prognostic and gene expression profile analysis in breast cancer

Breast cancer is the most frequently diagnosed malignant tumor in women and a major public health concern. NRF2 axis is a cellular protector signaling pathway protecting both normal and cancer cells from oxidative damage. NRF2 is a transcription factor that binds to the gene promoters containing antioxidant response element-like sequences. In this report, differential expression of NRF2 signaling pathway elements, as well as the correlation of NRF2 pathway mRNAs with various clinicopathologic characteristics, including molecular subtypes, tumor grade, tumor stage, and methylation status, has been investigated in breast cancer using METABRIC and TCGA datasets. In the current report, our findings revealed the deregulation of several NRF2 signaling elements in breast cancer patients. Moreover, there were negative correlations between the methylation of NRF2 genes and mRNA expression. The expression of NRF2 genes significantly varied between different breast cancer subtypes. In conclusion, substantial deregulation of NRF2 signaling components suggests an important role of these genes in breast cancer. Because of the clear associations between mRNA expression and methylation status, DNA methylation could be one of the mechanisms that regulate the NRF2 pathway in breast cancer. Differential expression of Hippo genes among various breast cancer molecular subtypes suggests that NRF2 signaling may function differently in different subtypes of breast cancer. Our data also highlights an interesting link between NRF2 components' transcription and tumor grade/stage in breast cancer.

Dengue fever ophthalmic manifestations: A review and update

Dengue fever, the most common arbovirus disease, affects an estimated 390 million people annually. Dengue virus (DENV) is an RNA virus of the Flaviviridae family with four different serotypes. Dengue haemorrhagic fever is the deadliest form of dengue infection and is characterised by thrombocytopaenia, hypotension, and the possibility of multi-system organ failure. The mechanism hypothesised for DENV viral replication is intrinsic antibody-dependent enhancement, which refers to Fcγ receptor-mediated viral amplification. This hypothesis suggests that the internalisation of DENV through the Fcγ receptor inhibits antiviral genes by suppressing type-1 interferon-mediated antiviral responses. DENV NS1 antibodies can promote the release of various inflammatory mediators in the nuclear transcription factor pathway (NF-κB-dependent), including monocyte chemoattractant protein (MCP)-1, interleukin (IL)-6, and IL-8. As a result, MCP-1 increases ICAM-1 expression and facilitates leukocyte transmigration. In addition, anti-DENV NS1 antibodies induce endothelial cell apoptosis via a nitric oxide-regulated pathway. A chain reaction involving pre-existing DENV heterotypic antibodies and innate immune cells causes dysfunction in complement system activity and contributes to the action of autoantibodies and anti-endothelial cells, resulting in endothelial cell dysfunction, blood-retinal barrier breakdown, haemorrhage, and plasma leakage. A spectrum of ocular diseases associated with DENV infection, ranging from haemorrhagic to inflammatory manifestations, has been reported in the literature. Although rare, ophthalmic manifestations can occur in both the anterior and posterior segments and are usually associated with thrombocytopenia. The most common ocular complication is haemorrhage. However, ophthalmic complications, such as anterior uveitis and vasculitis, suggest an immune-mediated pathogenesis.

EF-24, a Curcumin Analog, Inhibits Cancer Cell Invasion in Human Nasopharyngeal Carcinoma through Transcriptional Suppression of Matrix Metalloproteinase-9 Gene Expression

Cancer metastasis is a main cause of failure in treating subjects with nasopharyngeal carcinoma (NPC) and is frequently linked to high death rates. EF-24, an analog of curcumin, has exhibited many anti-cancer properties and enhanced bioavailability over curcumin. Nevertheless, the effects of EF-24 on the invasiveness of NPC are poorly understood. In this study, we demonstrated that EF-24 effectively inhibited TPA-induced motility and invasion responses of human NPC cells but elicited very limited cytotoxicity. In addition, the TPA-induced activity and expression of matrix metalloproteinase-9 (MMP-9), a crucial mediator of cancer dissemination, were found to be reduced in EF-24-treated cells. Our reporter assays revealed that such a reduction in MMP-9 expression by EF-24 was transcriptionally mediated by NF-κB via impeding its nuclear translocation. Further chromatin immunoprecipitation assays displayed that the EF-24 treatment decreased the TPA-induced interaction of NF-κB with the MMP-9 promoter in NPC cells. Moreover, EF-24 inhibited the activation of JNK in TPA-treated NPC cells, and the treatment of EF-24 together with a JNK inhibitor showed a synergistic effect on suppressing TPA-induced invasion responses and MMP-9 activities in NPC cells. Taken together, our data demonstrated that EF-24 restrained the invasiveness of NPC cells through the transcriptional suppression of MMP-9 gene expression, implicating the usefulness of curcumin or its analogs in controlling the spread of NPC.

Chemopreventive Activity of Ellagitannins from Acer pseudosieboldianum (Pax) Komarov Leaves on Prostate Cancer Cells

Several studies have shown that compounds from Acer pseudosieboldianum (Pax) Komarov leaves (APL) display potent anti-oxidative, anti-inflammatory, and anti-proliferative activities. Prostate cancer (PCa) is the most common cancer among older men, and DNA methylation is associated with PCa progression. This study aimed to investigate the chemopreventive activities of the compounds which were isolated from APL on prostate cancer cells and elucidate the mechanisms of these compounds in relation to DNA methylation. One novel ellagitannin [komaniin (14)] and thirteen other known compounds, including glucose derivatives [ethyl-β-D-glucopyranose (3) and (4R)-p-menth-1-ene-7,8-diol 7-O-β-D-glucopyranoside (4)], one phenylpropanoid [junipetrioloside A (5)], three phenolic acid derivatives [ellagic acid-4-β-D-xylopyranoside (1), 4-O-galloyl-quinic acid (2), and gallic acid (8)], two flavonoids [quercetin (11) and kaempferol (12)], and five hydrolysable tannins [geraniin (6), punicafolin (7), granatin B (9), 1,2,3,4,6-penta-galloyl-β-D-glucopyranoside (10), and mallotusinic acid (13)] were isolated from APL. The hydrolyzable tannins (6, 7, 9, 10, 13, and 14) showed potent anti-PCa proliferative and apoptosis-promoting activities. Among the compounds, the ellagitannins in the dehydrohexahydroxydiphenoyl (DHHDP) group (6, 9, 13, and 14), the novel compound 14 showed the most potent inhibitory activity on DNA methyltransferase (DNMT1, 3a and 3b) and glutathione S-transferase P1 methyl removing and re-expression activities. Thus, our results suggested that the ellagitannins (6, 9, 13, and 14) isolated from APL could be a promising treatment option for PCa.

T lymphocyte subsets and immunoglobulin and complement levels are associated with the infection status of patients with antineutrophil cytoplasmic antibody-associated vasculitis

BACKGROUND

Infection is the leading cause of death in patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV). The aim of this study was to characterize the immunological features of infectious events occurring in patients with newly diagnosed AAV and to identify possible risk factors associated with infection.

METHODS

The T lymphocyte subsets, immunoglobulin, and complement levels of the groups were compared between infected group and the noninfected group. Further, regression analysis was conducted to determine the association of each variable with the risk of infection.

RESULTS

280 patients with newly diagnosed AAV were enrolled. The average levels of CD3⁺ T cells (720.0 vs. 920.5, P < 0.001), CD3⁺CD4⁺ T cells (392.0 vs. 547.0, P < 0.001), and CD3⁺CD8⁺ T cells (248.0 vs. 335.0, P = 0.001), serum IgG (11.66 g/L vs. 13.59 g/L, P = 0.002), IgA (1.70 g/L vs. 2.44 g/L, P < 0.001), C3 (1.03 g/L vs. 1.09 g/L, P = 0.015), and C4 (0.24 g/L vs. 0.27 g/L, P < 0.001) were significantly lower in the infected group than in the noninfected group. The levels of CD3⁺CD4⁺ T cells (adjusted OR 0.997, P = 0.018), IgG (adjusted OR 0.804, P = 0.004), and C4 (adjusted OR 0.001, P = 0.013) were found independently associated with infection.

CONCLUSIONS

Patients of infected AAV and those without infection differ in T lymphocyte subsets and immunoglobulin and complement levels. Furthermore, CD3⁺CD4⁺ T cells counts and serum IgG and C4 levels were independent risk factors with infection in patients with newly diagnosed AAV.

C-Reactive Protein Levels Are Associated with Complement C4 Deposits and Interstitial Arteritis in ANCA-Associated Renal Vasculitis

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a potentially life-threatening systemic small-vessel vasculitis that is characterized by pauci-immune glomerulonephritis in case of kidney involvement, representing a major denominator of AAV mortality. Innate immunity with complement system activation is increasingly recognized in the pathogenesis of AAV and as an attractive therapeutic target. Although C-reactive protein (CRP) was thought to be a passive, nonspecific marker of inflammation, recent studies indicate that CRP plays a key role in the innate immune system by recognizing pathogens and altered self-determinants. Elevated baseline CRP at disease onset of AAV has already been described as a determinant of poor long-term outcomes. However, its clinical implications at disease onset of AAV, with respect to vasculitis manifestations and complement system activation that might also affect long-term outcomes, remain elusive. CRP levels were retrospectively analyzed in 53 kidney-biopsy-confirmed cases of ANCA-associated renal vasculitis; a total of 138 disease controls were also evaluated. Univariate and multivariate regression analysis was performed on clinicopathological parameters associated with CRP levels in ANCA-associated renal vasculitis. Results: Compared to disease controls, CRP elevation was common in ANCA-associated renal vasculitis and associated with de novo disease (p = 0.0169), critical illness (p = 0.0346), and severe deterioration of kidney function (p = 0.0167), independent of extrarenal disease manifestations. As confirmed by multiple regression analysis, CRP levels were correlated with active lesions predominated by interstitial arteritis in renal vasculitis, specifically with MPO-ANCA seropositivity (p = 0.0017). Based on analysis of systemic complement system activation and intrarenal complement deposits, CRP elevation was correlated specifically with complement C4 deposits in interstitial arteries in the subgroup with myeloperoxidase (MPO)-ANCA seropositivity (p = 0.039). Finally, this association was independent of systemic complement system activation, as reflected by the consumption of respective complement components. Here, we expand our current understanding of CRP in ANCA-associated renal vasculitis not only as an inflammatory marker, but potentially also as being involved in the pathogenesis of kidney injury by interaction with the complement system.

Reactivity of 7α-acetoxy-6β-hydroxyroyleanone and ability of its derivatives to modulate PKC isoforms.. [DOI: 10.21203/rs.3.rs-2456272/v1] [Cited by in Crossref: 0] [Impact Index Per Article: 0] Protein kinase C is a family of kinases that play important roles in carcinogenesis . Medicinal plants from Plectranthus spp. (Lamiaceae) are a well-known source of interesting abietanes, such as the 7α-acetoxy-6β-hydroxyroyleanone (Roy). The aim of this study was to extract and isolate Roy from P. grandidentatus Gürke and compare two extraction methods (the CO2 supercritical extraction and the ultrasound-assisted acetonic extraction). The aim is to designing new royleanone derivatives focused on PKC modulation for breast cancer therapy by molecular modeling. The concentration of Roy in the extracts was determined by HPLC-DAD. Supercritical extraction method afforded an extraction yield of 3.6% w/w, with the presence of 40.69 μg·mg-1 of Roy (yield of 0.14%), while ultrasound-assisted acetonic extraction afforded 2.3% w/w, with the presence of 52.67 μg·mg-1 of Roy (yield of 0.11%). The reactivity of Roy was investigated to synthetize new ester derivatives through Roy benzoylation, affording two different products, Roy-12-Bz and RoyBz. Similarly, from Roy acetylation, Roy-12-Ac and RoyAc were successfully prepared. Thus, a reactivity study pointed to the 12-OH position as the most reactive site for the esterification. It afforded ester derivatives, using mild conditions, with overall good yields (33–86%). For both positions’ derivatization, high temperature (50 °C), excess of reagents, and higher reaction time are recommended. Moreover, some royleanones were evaluated as PKC-α, βI, δ, ε and ζ activators. DeRoy displayed the most promising results with increased PKC activity for all the isoforms comparing to PMA and ARA. The results suggest that slightly changes in the royleanones structures’ may have a great impact in the selectivity towards each PKC isoform. New ester hit derivatives are currently in preparation based on this reactivity report, to be further evaluated as PKC modulators

Protein kinase C is a family of kinases that play important roles in carcinogenesis . Medicinal plants from Plectranthus spp. (Lamiaceae) are a well-known source of interesting abietanes, such as the 7α-acetoxy-6β-hydroxyroyleanone (Roy). The aim of this study was to extract and isolate Roy from P. grandidentatus Gürke and compare two extraction methods (the CO2 supercritical extraction and the ultrasound-assisted acetonic extraction). The aim is to designing new royleanone derivatives focused on PKC modulation for breast cancer therapy by molecular modeling. The concentration of Roy in the extracts was determined by HPLC-DAD. Supercritical extraction method afforded an extraction yield of 3.6% w/w, with the presence of 40.69 μg·mg-1 of Roy (yield of 0.14%), while ultrasound-assisted acetonic extraction afforded 2.3% w/w, with the presence of 52.67 μg·mg-1 of Roy (yield of 0.11%). The reactivity of Roy was investigated to synthetize new ester derivatives through Roy benzoylation, affording two different products, Roy-12-Bz and RoyBz. Similarly, from Roy acetylation, Roy-12-Ac and RoyAc were successfully prepared. Thus, a reactivity study pointed to the 12-OH position as the most reactive site for the esterification. It afforded ester derivatives, using mild conditions, with overall good yields (33–86%). For both positions’ derivatization, high temperature (50 °C), excess of reagents, and higher reaction time are recommended. Moreover, some royleanones were evaluated as PKC-α, βI, δ, ε and ζ activators. DeRoy displayed the most promising results with increased PKC activity for all the isoforms comparing to PMA and ARA. The results suggest that slightly changes in the royleanones structures’ may have a great impact in the selectivity towards each PKC isoform. New ester hit derivatives are currently in preparation based on this reactivity report, to be further evaluated as PKC modulators.

Role of Metabolism and Metabolic Pathways in Prostate Cancer

Prostate cancer (PCa) is the common cause of death in men. The pathophysiological factors contributing to PCa are not well known. PCa cells gain a protective mechanism via abnormal lipid signaling and metabolism. PCa cells modify their metabolism in response to an excessive intake of nutrients to facilitate advancement. Metabolic syndrome (MetS) is inextricably linked to the carcinogenic progression of PCa, which heightens the severity of the disease. It is hypothesized that changes in the metabolism of the mitochondria contribute to the onset of PCa. The studies of particular alterations in the progress of PCa are best accomplished by examining the metabolome of prostate tissue. Due to the inconsistent findings written initially, additional epidemiological research is required to identify whether or not MetS is an aspect of PCa. There is a correlation between several risk factors and the progression of PCa, one of which is MetS. The metabolic symbiosis between PCa cells and the tumor milieu and how this type of crosstalk may aid in the development of PCa is portrayed in this work. This review focuses on in-depth analysis and evaluation of the metabolic changes that occur within PCa, and also aims to assess the effect of metabolic abnormalities on the aggressiveness status and metabolism of PCa.

The proteomic landscape shows oncologic relevance in cystitis glandularis

BACKGROUND

The relationship between cystitis glandularis (CG) and bladder malignancy remains unclear.

METHODS

We identified the oncologic significance of CG at the molecular level using liquid chromatography-tandem mass spectrometry-based proteomic analysis of 10 CG, 12 urothelial carcinoma (UC), and nine normal urothelium (NU) specimens. Differentially expressed proteins (DEPs) were identified based on an analysis of variance false discovery rate < 0.05, and their functional enrichment was analyzed using a network model, Gene Set Enrichment Analysis, and Gene Ontology annotation.

RESULTS

We identified 9,890 proteins across all samples and 1,139 DEPs among the three entities. A substantial number of DEPs overlapped in CG/NU, distinct from UC. Interestingly, we found that a subset of DEP clusters (n = 53, 5%) was differentially expressed in NU but similarly between CG and UC. This "UC-like signature" was enriched for reactive oxygen species (ROS) and energy metabolism, growth and DNA repair, transport, motility, epithelial-mesenchymal transition, and cell survival. Using the top 10 shortlisted DEPs, including SOD2, PRKCD, CYCS, and HCLS1, we identified functional elements related to ROS metabolism, development, and transport using network analysis. The abundance of these four molecules in UC/CG than in NU was consistent with the oncologic functions in CG.

CONCLUSIONS

Using a proteomic approach, we identified a predominantly non-neoplastic landscape of CG, which was closer to NU than to UC. We also confirmed a small subset of common DEPs in UC and CG, suggesting that altered ROS metabolism might imply potential cancerous risks in CG.

Characterizing the Role of Calcium Sensing Receptor in the Progression of Obesity-Mediated Aggressive Prostate Cancer Phenotype

Obesity increases the risk of advanced prostate cancer (PCa). The calcium sensing receptor (CaSR) has been shown to be responsive to obesity-mediated cytokines and is upregulated in metastatic PCa. This study used a novel in vitro approach, involving the exposure of PCa cells to sera, from obese or normal weight males, and to CaSR inhibitor NPS-2143. Cell viability was determined using MTT assay. MMP-9 activity and invasion were assessed using zymography and invasion chambers, respectively. Microscopy was used to visualize EMT proteins. qRT-PCR and immunoblot analysis were used to quantify changes in genes and proteins important for tumorigenesis. Exposure to obese sera increased the proliferation, and the invasive capacity of PCa cells and de-localized epithelial-mesenchymal transition markers, which were attenuated with CaSR inhibition. Exposure to obese sera upregulated mRNA expression of PTHrP and protein expression of COX-2, IL-6, and CaSR. Inhibition of CaSR downregulated the mRNA expression of PTHrP and RANK, and protein expression of pERK and TNF-α. Obesity was shown to increase invasion and upregulate the expression of genes and proteins involved in PCa tumorigenesis. CaSR inhibition downregulated the expression of several of these factors. Thus, CaSR is a potentially important protein to target in obesity-mediated PCa progression.

Protein kinase C epsilon promotes de novo lipogenesis and tumor growth in prostate cancer cells by regulating the phosphorylation and nuclear translocation of pyruvate kinase isoform M2

Protein kinase C epsilon (PKCε) belongs to a family of serine/threonine kinases that control cell proliferation, differentiation and survival. Aberrant PKCε activation and overexpression is a frequent feature of numerous cancers. However, its role in regulation of lipid metabolism in cancer cells remains elusive. Here we report a novel function of PKCε in regulating of prostate cancer cell proliferation by modulation of PKM2-mediated de novo lipogenesis. We show that PKCε promotes de novo lipogenesis and tumor cell proliferation via upregulation of lipogenic enzymes and lipid contents in prostate cancer cells. Mechanistically, PKCε interacts with NABD (1-388) domain of C-terminal deletion on pyruvate kinase isoform M2 (PKM2) and enhances the Tyr105 phosphorylation of PKM2, leading to its nuclear localization. Moreover, forced expression of mutant Tyr105 (Y105F) or PKM2 inhibition suppressed de novo lipogenesis and cell proliferation induced by overexpression of PKCε in prostate cancer cells. In a murine tumor model, inhibitor of PKM2 antagonizes lipogenic enzymes expression and prostate cancer growth induced by overexpression of PKCε in vivo. These data indicate that PKCε is a critical regulator of de novo lipogenesis, which may represent a potential therapeutic target for the treatment of prostate cancer.

The Many Faces of Hemolysis

Hemolysis is a problem associated with a variety of red cell pathologies and physiologies not limited to the transfusion of cells. Various pathways lead to the observed outcomes when a hemolytic event occurs. Each event, and the pathway it follows, is based on characteristics of the red cell, the location in which the hemolysis occurs, and the interaction of the immune system. The severity of an event can be predicted with the knowledge of how these 3 factors interface. Although not all hemolytic events are alike, similarities may exist when the pathways overlap.

Evidence of Chronic Complement Activation in Asymptomatic Pediatric Brain Injury Patients: A Pilot Study

Physical insult from a mild Traumatic Brain Injury (mTBI) leads to changes in blood flow in the brain and measurable changes in white matter, suggesting a physiological basis for chronic symptom presentation. Post-traumatic headache (PTH) is frequently reported by persons after an mTBI that may persist beyond the acute period (>3 months). It remains unclear whether ongoing inflammation may contribute to the clinical trajectory of PTH. We recruited a cohort of pediatric subjects with PTH who had an acute or a persistent clinical trajectory, each around the 3-month post-injury time point, as well as a group of age and sex-matched healthy controls. We collected salivary markers of mRNA expression as well as brain imaging and psychological testing. The persistent PTH group showed the highest levels of psychological burden and pain symptom reporting. Our data suggest that the acute and persistent PTH cohort had elevated levels of complement factors relative to healthy controls. The greatest change in mRNA expression was found in the acute-PTH cohort wherein the complement cascade and markers of vascular health showed a prominent role for C1Q in PTH pathophysiology. These findings (1) underscore a prolonged engagement of what is normally a healthy response and (2) show that a persistent PTH symptom trajectory may parallel a poorly regulated inflammatory response.

Curcuminoid supplementation in canine diabetic mellitus and its complications using proteomic analysis

Introduction

Inflammation and oxidative stress contribute to diabetes pathogenesis and consequences. Therapeutic approaches for canine diabetes remain a challenge. Curcumin has anti-inflammatory and anti-oxidative effects and is beneficial for humans with diabetes mellitus (DM); however, data on its impact on canine diabetes is limited. This study aimed to evaluate the potential for causing adverse effects, anti-inflammatory effects, anti-oxidative effects and proteomic patterns of curcuminoid supplementation on canine DM.

Methods

Altogether, 18 dogs were divided into two groups: DM (n = 6) and healthy (n = 12). Curcuminoid 250 mg was given to the DM group orally daily for 180 days. Blood and urine sample collection for hematological parameters, blood biochemistry, urinalysis, oxidative stress parameters, inflammatory markers and proteomics were performed every 6 weeks.

Results and discussion

Curcuminoid supplementation with standard therapy significantly decreased oxidative stress with the increased glutathione/oxidized glutathione ratio, but cytokine levels were unaffected. According to the proteomic analysis, curcuminoid altered the expression of alpha-2-HS-glycoprotein, transthyretin, apolipoprotein A-I and apolipoprotein A-IV, suggesting that curcuminoid improves insulin sensitivity and reduces cardiovascular complications. No negative impact on clinical symptoms, kidneys or liver markers was identified. This study proposed that curcuminoids might be used as a targeted antioxidant strategy as an adjunctive treatment to minimize diabetes complications in dogs.

Autoimmunity in Infection-Related Glomerulonephritis

Introduction

Autoimmune (AI) reactivity in the setting of infection-related GN (IRGN) is often viewed as an epiphenomenon and is not well described.

Methods

We report a cohort of 17 patients with IRGN during a 7-year period that highlights cases with AI reactivity and describes the clinical and pathologic characteristics of IRGN cases associated with AI reactivity.

Results

Of the IRGN cases, 76% had clinical evidence of an autoimmune disease (AD) and/or positive AI serologies. Within the IRGN group with AI reactivity, 12 had positive AI serologies (92%) and 10 had AD (77%). 30% had a prior diagnosis of AD, while the remaining 70% did not have a history of AD and were either diagnosed or suspected of having an AD at the time of biopsy. The most common autoantibody detected was anti-nuclear antibody followed by anti-neutrophil cytoplasmic antibodies and autoantibodies associated with antiphospholipid syndrome.

Conclusion

The study is not sufficiently powered to determine any significance but demonstrates the frequency with which AI features occur in IRGN and should prompt further future investigation. In summary, our findings suggest AI manifestations are common in IRGN.

The complement system and human autoimmune diseases

Genetic deficiencies of early components of the classical complement activation pathway (especially C1q, r, s, and C4) are the strongest monogenic causal factors for the prototypic autoimmune disease systemic lupus erythematosus (SLE), but their prevalence is extremely rare. In contrast, isotype genetic deficiency of C4A and acquired deficiency of C1q by autoantibodies are frequent among patients with SLE. Here we review the genetic basis of complement deficiencies in autoimmune disease, discuss the complex genetic diversity seen in complement C4 and its association with autoimmune disease, provide guidance as to when clinicians should suspect and test for complement deficiencies, and outline the current understanding of the mechanisms relating complement deficiencies to autoimmunity. We focus primarily on SLE, as the role of complement in SLE is well-established, but will also discuss other informative diseases such as inflammatory arthritis and myositis.

Insights into the Antibacterial Properties of Complement Peptides C3a, C4a, and C5a across Vertebrates

Complement peptides C3a, C4a, and C5a are important components of innate immunity in vertebrates. Although they diverged from a common ancestor, only C3a and C4a can act as antibacterial peptides in Homo sapiens, suggesting that C5a has evolved into a purely chemotactic molecule; however, the antibacterial properties of C3a, C4a, and C5a across vertebrates still require elucidation. In this article, we show that, unlike those in H. sapiens, Mus musculus C3a, C4a, and C5a all possess antibacterial activities, implying that the antibacterial properties of C3a, C4a, and C5a have evolved divergently in vertebrates. The extremely different net charge, a key factor determining the antibacterial activities of cationic antimicrobial peptides, of vertebrate C3a, C4a, and C5a supports this speculation. Moreover, the antibacterial activity of overlapping peptides covering vertebrate C3a, C4a, and C5a further strongly supports the speculation, because their activity is positively correlated with the net charge of source molecules. Notably, the structures of C3a, C4a, and C5a are conserved in vertebrates, and the inactive overlapping peptides can become antibacterial peptides if mutated to possess enough net positive charges, indicating that net charge is the only factor determining the antibacterial properties of vertebrate C3a, C4a, and C5a. More importantly, many vertebrate C3a-, C4a-, and C5a-derived peptides possess high antibacterial activities yet exhibit no hemolytic activities, suggesting the application potential in anti-infective therapy. Taken together, our findings reveal that vertebrate C3a, C4a, and C5a are all sources of antibacterial peptides that will facilitate the design of excellent peptide antibiotics.

RAC1, a Potential Diagnostic and Prognostic Marker for Diffuse Large B Cell Lymphoma

The gene changes for diagnosis and prognosis of diffuse large B cell lymphoma (DLBCL) still remain unclear. RAC1 was reported to be asso;ciated with the B cell receptor signal pathway, but its relations with DLBCL have not yet been systematically explored. In this study, we have conducted molecular, bioinformatics and clinical analyses by using publicly available data from The Cancer Genome Atlas (TCGA). Wilcoxon signed-rank test and logistic regression were performed to evaluate the association between RAC1 and clinical features in patients. Kaplan-Meier and Cox regression methods were used to examine the impacts of RAC1 expression level on overall survival, and a nomogram was performed to illustrate the correlation between RAC1 and the risk of DLBCL. Our results revealed that the expression level of RAC1 in DLBCL was higher than that in normal tissues or lymphadenitis. High-level expression of RAC1 was significantly associated with clinical stage, as well as being an independent factor affecting overall survival. RAC1 was negatively correlated with Bruton's tyrosine kinase (BTK). The association between RAC1 gene expression and the risk of DLBCL was presented in a nomogram. In conclusion, RAC1 expression patterns may be used to predict the development and prognosis of DLBCL.

Androgen Receptor Signaling Inhibition in Advanced Castration Resistance Prostate Cancer: What Is Expected for the Near Future?

The androgen signaling pathway is the cornerstone in the treatment of high risk or advanced prostate cancer patients. However, in recent years, different mechanisms of resistance have been defined in this field, limiting the efficacy of the currently approved antiandrogen drugs. Different therapeutic approaches are under research to assess the role of combination therapies against escape signaling pathways or the development of novel antiandrogen drugs to try to solve the primary or acquired resistance against androgen dependent or independent pathways. The present review aims to summarize the current state of androgen inhibition in the therapeutic algorithm of patients with advanced prostate cancer and the mechanisms of resistance to those available drugs. In addition, this review conducted a comprehensive overview of the main present and future research approaches in the field of androgen receptor inhibition to overcome these resistances and the potential new drugs under research coming into this setting.

Genome-wide detection of positive and balancing selection signatures shared by four domesticated rainbow trout populations (Oncorhynchus mykiss).. [DOI: 10.1101/2022.12.08.519621] [Cited by in Crossref: 0] [Impact Index Per Article: 0] Evolutionary processes leave footprints across the genome over time. Highly homozygous regions may correspond to positive selection of favourable alleles, while maintenance of heterozygous regions may be due to balancing selection phenomena. We analyzed 176 genomes coming from 20 sequenced US fish and 156 fish from three different French lines that were genotyped using a HD Axiom Trout Genotyping 665K SNP Array. Using methods based on either Run of Homozygosity or Extended Haplotype Homozygosity, we detected selection signals in four domesticated rainbow trout populations. Nine genomic regions composed of 253 genes, mainly located on chromosome 2 but also on chromosomes 12, 15, 16, and 20, were identified under positive selection in all four populations. In addition, four heterozygous regions containing 29 genes putatively under balancing selection were also shared by the four populations and located on chromosomes 10, 13, and 19. Whatever the homozygous or heterozygous nature of the region, we always found some genes highly conserved among vertebrates due to their critical roles in cellular and nuclear organisation, embryonic development or immunity. We identify new promising candidate genes involved in rainbow trout fitness, as well as genes already detected under positive selection in other fishes (auts2, atp1b3, zp4, znf135, igf-1α, brd2, col9a2, mrap2, pbx1, emilin-3). These findings represent a genome-wide map of signatures of selection common over rainbow trout populations, which is the foundation to understand the processes in action and to identify what kind of diversity should be preserved, or conversely avoided in breeding programs, in order to maintain or improve essential biological functions in domesticated rainbow trout populations

Evolutionary processes leave footprints across the genome over time. Highly homozygous regions may correspond to positive selection of favourable alleles, while maintenance of heterozygous regions may be due to balancing selection phenomena. We analyzed 176 genomes coming from 20 sequenced US fish and 156 fish from three different French lines that were genotyped using a HD Axiom Trout Genotyping 665K SNP Array. Using methods based on either Run of Homozygosity or Extended Haplotype Homozygosity, we detected selection signals in four domesticated rainbow trout populations. Nine genomic regions composed of 253 genes, mainly located on chromosome 2 but also on chromosomes 12, 15, 16, and 20, were identified under positive selection in all four populations. In addition, four heterozygous regions containing 29 genes putatively under balancing selection were also shared by the four populations and located on chromosomes 10, 13, and 19. Whatever the homozygous or heterozygous nature of the region, we always found some genes highly conserved among vertebrates due to their critical roles in cellular and nuclear organisation, embryonic development or immunity. We identify new promising candidate genes involved in rainbow trout fitness, as well as genes already detected under positive selection in other fishes (auts2, atp1b3, zp4, znf135, igf-1α, brd2, col9a2, mrap2, pbx1, emilin-3). These findings represent a genome-wide map of signatures of selection common over rainbow trout populations, which is the foundation to understand the processes in action and to identify what kind of diversity should be preserved, or conversely avoided in breeding programs, in order to maintain or improve essential biological functions in domesticated rainbow trout populations.

Obesity Contributes to Inflammation in Patients with IBS via Complement Component 3 and C-Reactive Protein

Irritable Bowel Syndrome (IBS) is usually a lifelong state that disturbs the digestive system. IBS has been linked to low-grade inflammation and the release of inflammatory mediators into the bloodstream. This could be associated with the degree of obesity presented by patients with IBS. Reports imply that IBS is more frequent in obese patients than in the overall population, with a prevalence of up to 31%. Here, we evaluated the serum levels of immunological and inflammation molecules and their correlation with Body Mass Index in IBS patients and the healthy control (HC). Seventy-nine serum samples of the IBS patients and thirty-five of the HC group were analyzed to determine the levels of each molecule and compare them with their BMI. Serum levels of C3 and C4 were significantly increased in IBS patients. C3 and C4 levels were higher in IBS-M and IBS-D subtypes compared with the HC group. When patients were grouped by BMI, a positive correlation between serum C3 (r = 0.49, p < 0.0001) and CRP (r = 0.40, p < 0.001) levels was found. Our results show, for the first time, a correlation between immunological molecules and BMI in IBS patients, suggesting that the inflammatory nature of obesity could contribute to the development of the symptoms in IBS through the stimulation and release of proteins as complement components and CRP.

Tear-derived exosomal biomarkers of Graves' ophthalmopathy

Graves' ophthalmopathy (GO), the most frequent extrathyroidal manifestation of Graves' disease (GD), can lead to a significant decline in the quality of life in patients. Exosomes, which contain proteins, lipids and DNA, play important roles in the pathological processes of various diseases. However, their roles in Graves' ophthalmopathy are still unclear. We aimed to isolate exosomes and analyze the different exosomal proteins. Tear fluids were collected from twenty-four GO patients, twenty-four GD patients and sixteen control subjects. The numbers of tear exosomes were assayed using nanoparticle tracking analysis. A Luminex 200 kit and ELISA kit were used to confirm the different cytokine concentrations in serum. Extraocular muscle from GO patients and controls was extracted, and western blotting was used to assay the levels of Caspase-3 and complement C4A. Our study demonstrated that the number of tear exosomes differ from GD patients and control. The expression levels of cytokines, including IL-1 and IL-18, were significantly increased in the tear exosomes and serum from GO patients compared with GD patients and controls. The levels of the exosomal proteins Caspase-3, complement C4A and APOA-IV were significantly increased in GO patients compared to GD patients and controls. Orbital fibroblasts from GO patients showed significantly higher levels of Caspase-3 and complement C4A than those from controls. The levels of serum APOA-IV in GO patients were significantly higher than those in GD patients and controls. Specific proteins showed elevated expression in tear exosomes from GO patients, indicating that they may play important roles in GO pathogenesis.

Kalirin mediates Rac1 activation downstream of calcium/calmodulin-dependent protein kinase II to stimulate glucose uptake during muscle contraction

In this study, we investigated the role of calcium/calmodulin-dependent protein kinase II (CaMKII) in contraction-stimulated glucose uptake in skeletal muscle. C2C12 myotubes were contracted by electrical pulse stimulation (EPS), and treadmill running was used to exercise mice. The activities of CaMKII, the small G protein Rac1, and the Rac1 effector kinase PAK1 were elevated in muscle by running exercise or EPS, while they were lowered by the CaMKII inhibitor KN-93 and/or small interfering RNA (siRNA)-mediated knockdown. EPS induced the mRNA and protein expression of the Rac1-GEF Kalirin in a CaMKII-dependent manner. EPS-induced Rac1 activation was lowered by the Kalirin inhibitor ITX3 or siRNA-mediated Kalirin knockdown. KN-93, ITX3, and siRNA-mediated Kalirin knockdown reduced EPS-induced glucose uptake. These findings define a CaMKII-Kalirin-Rac1 signaling pathway that contributes to contraction-stimulated glucose uptake in skeletal muscle myotubes and tissue.

Association of PKCi variant and its gene expression with breast cancer prognosis.. [DOI: 10.21203/rs.3.rs-2299569/v1] [Cited by in Crossref: 0] [Impact Index Per Article: 0] Breast cancer is one of the most common causes of fatalities in females globally. Rising cases of drug resistance against existing chemotherapeutics are great problem. To address this issue, there is a need to find appropriate biomarker that could be used to detect cancer at early stages, so drug resistance development can be avoided. Protein Kinase C iota (PKCɩ), an AGC kinase, has an oncogenic role in cancers and its expression and SNPs have been reported to be associated with the cancer development. So, the study aims were to examine the expression of PKCɩ, Protein Kinase B (AKT), Suppressor of cytokine signaling 3 (SOC3), Vascular endothelial growth factor (VEGF), Krupple like factor 3 (KLF3), Tumor protein D52 (TPD52), Hypoxia inducible factor (HIF1α) and microRNA-124 (miR-124) in breast cancer and association of PKCɩ variants (G34W & F66Y) with breast cancer.: Genetic expression assay was performed through real time PCR, whereas the genotypic association of PKCɩ SNPs with breast cancer was accomplished through Tetra-ARMS PCR. The overall expression levels of PKCɩ, AKT, SOC3, VEGF, HIF1α and TPD52 were elevated in patients as compared to control whereas the expression levels of miR-124 and KLF3 were lowered in patients. Positive association of variant G34W (TT) of PKCɩ with breast cancer has been explored while no association of variant F66Y with breast cancer was found. Hence, the results suggest that PKCɩ and related genes can serve as the potential biomarkers for the early-diagnosis and prognosis of breast cancer

Breast cancer is one of the most common causes of fatalities in females globally. Rising cases of drug resistance against existing chemotherapeutics are great problem. To address this issue, there is a need to find appropriate biomarker that could be used to detect cancer at early stages, so drug resistance development can be avoided. Protein Kinase C iota (PKCɩ), an AGC kinase, has an oncogenic role in cancers and its expression and SNPs have been reported to be associated with the cancer development. So, the study aims were to examine the expression of PKCɩ, Protein Kinase B (AKT), Suppressor of cytokine signaling 3 (SOC3), Vascular endothelial growth factor (VEGF), Krupple like factor 3 (KLF3), Tumor protein D52 (TPD52), Hypoxia inducible factor (HIF1α) and microRNA-124 (miR-124) in breast cancer and association of PKCɩ variants (G34W & F66Y) with breast cancer.: Genetic expression assay was performed through real time PCR, whereas the genotypic association of PKCɩ SNPs with breast cancer was accomplished through Tetra-ARMS PCR. The overall expression levels of PKCɩ, AKT, SOC3, VEGF, HIF1α and TPD52 were elevated in patients as compared to control whereas the expression levels of miR-124 and KLF3 were lowered in patients. Positive association of variant G34W (TT) of PKCɩ with breast cancer has been explored while no association of variant F66Y with breast cancer was found. Hence, the results suggest that PKCɩ and related genes can serve as the potential biomarkers for the early-diagnosis and prognosis of breast cancer.

An ErbB Lineage Co-Regulon Harbors Potentially Co-Druggable Targets for Multimodal Precision Therapy in Head and Neck Squamous Cell Carcinoma

The ErbB lineage of oncogenic receptor tyrosine kinases is frequently overexpressed in head and neck squamous cell carcinomas. A common co-regulon triggered by the ErbB proteins; involving shared signaling circuitries; may harbor co-druggable targets or response biomarkers for potential future multimodal precision therapy in ErbB-driven head and neck squamous cell carcinoma. We here present a cohort-based; genome-wide analysis of 488 head and neck squamous cell carcinomas curated as part of The Cancer Genome Atlas Project to characterize genes that are significantly positively co-regulated with the four ErbB proteins and those that are shared among all ErbBs denoting a common ErbB co-regulon. Significant positive gene correlations involved hundreds of genes that were co-expressed with the four ErbB family members (q < 0.05). A common; overlapping co-regulon consisted of a core set of 268 genes that were uniformly co-regulated with all four ErbB genes and highly enriched for functions in chromatin organization and histone modifications. This high-priority set of genes contained ten putative antineoplastic drug-gene interactions. The nature and directionality of these ten drug-gene associations was an inhibiting interaction for seven (PIK3CB; PIK3C2B; HDAC4; FRK; PRKCE; EPHA4; and DYRK1A) of them in which the drug decreases the biological activity or expression of the gene target. For three (CHD4; ARID1A; and PBRM1) of the associations; the directionality of the interaction was such that the gene predicted sensitivit y to the drug suggesting utility as potential response biomarkers. Drug-gene interactions that predicted the gene product to be reduced by the drug included a variety of potential targeted molecular agent classes. This unbiased genome-wide analysis identified a target-rich environment for multimodal therapeutic approaches in tumors that are putatively ErbB-driven. The results of this study require preclinical validation before ultimately devising lines of combinatorial treatment strategies for ErbB-dependent head and neck squamous cell carcinomas that incorporate these findings.

Protein Kinase C (PKC) Isozymes as Diagnostic and Prognostic Biomarkers and Therapeutic Targets for Cancer

Protein kinase C (PKC) is a large family of calcium- and phospholipid-dependent serine/threonine kinases that consists of at least 11 isozymes. Based on their structural characteristics and mode of activation, the PKC family is classified into three subfamilies: conventional or classic (cPKCs; α, βI, βII, and γ), novel or non-classic (nPKCs; δ, ε, η, and θ), and atypical (aPKCs; ζ, ι, and λ) (PKCλ is the mouse homolog of PKCι) PKC isozymes. PKC isozymes play important roles in proliferation, differentiation, survival, migration, invasion, apoptosis, and anticancer drug resistance in cancer cells. Several studies have shown a positive relationship between PKC isozymes and poor disease-free survival, poor survival following anticancer drug treatment, and increased recurrence. Furthermore, a higher level of PKC activation has been reported in cancer tissues compared to that in normal tissues. These data suggest that PKC isozymes represent potential diagnostic and prognostic biomarkers and therapeutic targets for cancer. This review summarizes the current knowledge and discusses the potential of PKC isozymes as biomarkers in the diagnosis, prognosis, and treatment of cancers.

PROTEIN KINASE C ALPHA IS A CENTRAL NODE FOR TUMORIGENIC TRANSCRIPTIONAL NETWORKS IN HUMAN PROSTATE CANCER

Aberrant expression of protein kinase C (PKC) isozymes is a hallmark of cancer. The different members of the PKC family control cellular events associated with cancer development and progression. Whereas the classical/conventional PKCα isozyme has been linked to tumor suppression in most cancer types, here we demonstrate that this kinase is required for the mitogenic activity of aggressive human prostate cancer cells displaying aberrantly high PKCα expression. Immunohistochemical analysis showed abnormal up-regulation of PKCα in human primary prostate tumors. Interestingly, silencing PKCα expression from aggressive prostate cancer cells impairs cell cycle progression, proliferation and invasion, as well as their tumorigenic activity in a mouse xenograft model. Mechanistic analysis revealed that PKCα exerts a profound control of gene expression, particularly over genes and transcriptional networks associated with cell cycle progression and E2F transcription factors. PKCα RNAi depletion from PC3 prostate cancer cells led to a reduction in the expression of pro-inflammatory cytokine and epithelial-to-mesenchymal transition (EMT) genes, as well as a prominent down-regulation of the immune checkpoint ligand PD-L1. This PKCα-dependent gene expression profile was corroborated in silico using human prostate cancer databases. Our studies established PKCα as a multifunctional kinase that plays pleiotropic roles in prostate cancer, particularly by controlling genetic networks associated with tumor growth and progression. The identification of PKCα as a pro-tumorigenic kinase in human prostate cancer provides strong rationale for the development of therapeutic approaches towards targeting PKCα or its effectors.

Semaphorin signaling restricts neuronal regeneration in C. elegans

Extracellular signaling proteins serve as neuronal growth cone guidance molecules during development and are well positioned to be involved in neuronal regeneration and recovery from injury. Semaphorins and their receptors, the plexins, are a family of conserved proteins involved in development that, in the nervous system, are axonal guidance cues mediating axon pathfinding and synapse formation. The Caenorhabditis elegans genome encodes for three semaphorins and two plexin receptors: the transmembrane semaphorins, SMP-1 and SMP-2, signal through their receptor, PLX-1, while the secreted semaphorin, MAB-20, signals through PLX-2. Here, we evaluate the locomotion behavior of knockout animals missing each of the semaphorins and plexins and the neuronal morphology of plexin knockout animals; we described the cellular expression pattern of the promoters of all plexins in the nervous system of C. elegans; and we evaluated their effect on the regrowth and reconnection of motoneuron neurites and the recovery of locomotion behavior following precise laser microsurgery. Regrowth and reconnection were more prevalent in the absence of each plexin, while recovery of locomotion surpassed regeneration in all genotypes.

Pharmacophore modeling, docking and molecular dynamics simulation for identification of novel human protein kinase C beta (PKCβ) inhibitors

Protein kinase Cβ (PKCβ) is considered as an attractive molecular target for the treatment of COVID-19-related acute respiratory distress syndrome (ARDS). Several classes of inhibitors have been already identified. In this article, we developed and validated ligand-based PKCβ pharmacophore models based on the chemical structures of the known inhibitors. The most accurate pharmacophore model, which correctly predicted more than 70% active compounds of test set, included three aromatic pharmacophore features without vectors, one hydrogen bond acceptor pharmacophore feature, one hydrophobic pharmacophore feature and 158 excluded volumes. This pharmacophore model was used for virtual screening of compound collection in order to identify novel potent PKCβ inhibitors. Also, molecular docking of compound collection was performed and 28 compounds which were selected simultaneously by two approaches as top-scored were proposed for further biological research.

Complement component C4 structural variation and quantitative traits contribute to sex-biased vulnerability in systemic sclerosis

Copy number (CN) polymorphisms of complement C4 play distinct roles in many conditions, including immune-mediated diseases. We investigated the association of C4 CN with systemic sclerosis (SSc) risk. Imputed total C4, C4A, C4B, and HERV-K CN were analyzed in 26,633 individuals and validated in an independent cohort. Our results showed that higher C4 CN confers protection to SSc, and deviations from CN parity of C4A and C4B augmented risk. The protection contributed per copy of C4A and C4B differed by sex. Stronger protection was afforded by C4A in men and by C4B in women. C4 CN correlated well with its gene expression and serum protein levels, and less C4 was detected for both in SSc patients. Conditioned analysis suggests that C4 genetics strongly contributes to the SSc association within the major histocompatibility complex locus and highlights classical alleles and amino acid variants of HLA-DRB1 and HLA-DPB1 as C4-independent signals.

Herpesvirus Infections in the Human Brain: A Neural Cell Model of the Complement System Derived from Induced Pluripotent Stem Cells

BACKGROUND

Herpesviruses alter cognitive functions in humans following acute infections; progressive cognitive decline and dementia have also been suggested. It is important to understand the pathogenic mechanisms of such infections. The complement system - comprising functionally related proteins integral for systemic innate and adaptive immunity - is an important component of host responses. The complement system has specialized functions in the brain. Still, the dynamics of the brain complement system are still poorly understood. Many complement proteins have limited access to the brain from plasma, necessitating synthesis and specific regulation of expression in the brain; thus, complement protein synthesis, activation, regulation, and signaling should be investigated in human brain-relevant cellular models. Cells derived from human-induced pluripotent stem cells (hiPSCs) could enable tractable models.

METHODS

Human-induced pluripotent stem cells were differentiated into neuronal (hi-N) and microglial (hi-M) cells that were cultured with primary culture human astrocyte-like cells (ha-D). Gene expression analyses and complement protein levels were analyzed in mono- and co-cultures.

RESULTS

Transcript levels of complement proteins differ by cell type and co-culture conditions, with evidence for cellular crosstalk in co-cultures. Hi-N and hi-M cells have distinct patterns of expression of complement receptors, soluble factors, and regulatory proteins. hi-N cells produce complement factor 4 (C4) and factor B (FB), whereas hi-M cells produce complement factor 2 (C2) and complement factor 3 (C3). Thus, neither hi-N nor hi-M cells can form either of the C3-convertases - C4bC2a and C3bBb. However, when hi-N and hi-M cells are combined in co-cultures, both types of functional C3 convertase are produced, indicated by elevated levels of the cleaved C3 protein, C3a.

CONCLUSIONS

hiPSC-derived co-culture models can be used to study viral infection in the brain, particularly complement receptor and function in relation to cellular "crosstalk." The models could be refined to further investigate pathogenic mechanisms.

Neuropilin-2 Signaling Modulates Mossy Fiber Sprouting by Regulating Axon Collateral Formation Through CRMP2 in a Rat Model of Epilepsy

Programmed neural circuit formation constitutes the foundation for normal brain functions. Axon guidance cues play crucial roles in neural circuit establishment during development. Whether or how they contribute to maintaining the stability of networks in mature brains is seldom studied. Upon injury, neural rewiring could happen in adulthood, of which mossy fiber sprouting (MFS) is a canonical example. Here, we uncovered a novel role of axon guidance molecule family Sema3F/Npn-2 signaling in MFS and epileptogenesis in a rat model of epilepsy. Dentate gyrus-specific Npn-2 knockdown increased seizure activity in epileptic animals along with increased MFS. Hippocampal culture results suggested that Npn-2 signaling modulates MFS via regulating axon outgrowth and collateral formation. In addition, we discovered that Sema3F/Npn-2 signal through CRMP2 by regulating its phosphorylation in the process of MFS. Our work illustrated that Npn-2 signaling in adult epilepsy animals could potentially modulate seizure activity by controlling MFS. MFS constitutes the structural basis for abnormal electric discharge of neurons and recurrent seizures. Therapies targeting Npn-2 signaling could potentially have disease-modifying anti-epileptogenesis effects in epilepsy treatment.

Adipose transplantation improves olfactory function and neurogenesis via PKCα-involved lipid metabolism in Seipin Knockout mice.. [DOI: 10.21203/rs.3.rs-1948538/v1] [Cited by in Crossref: 0] [Impact Index Per Article: 0] Lipodystrophy-associated Metabolic Disorders caused by Seipin deficiency lead to not only severe lipodystrophy but also neurological disorders. However, the underlying mechanism of Seipin deficiency-induced neuropathy is not well elucidated and the possible restorative strategy needs to be explored. In the present study, we investigated the systemic lipid metabolic abnormalities of Seipin knockout (KO) mice and their effect on adult neurogenesis in the subventricular zone (SVZ) and olfactory function. It was found that KO mice presented an ectopic accumulation of lipid in the lateral ventricle, accompanied by decreased neurogenesis in adult SVZ, diminished new neuron formation in the olfactory bulb, and impaired olfactory-related memory. Transcriptome analysis showed that the differentially expressed genes (DEGs) in SVZ tissues of adult KO mice were significantly enriched in biological processes related to lipid metabolism. Mass spectrometry imaging showed that the levels of glycerophospholipid, diglyceride and ceramide were significantly increased. In the restorative study, we found that subcutaneous adipose tissue transplantation (AT) rescued the abnormality of peripheral metabolism in KO mice and ameliorated the ectopic lipid accumulation in SVZ, concomitant with restoration of the SVZ neurogenesis and olfactory function. Mechanistically, PKCα was the potential mediator of lipid dysregulation-induced phenotypes. In the brain tissue of KO mice, PKCα was upregulated, which could be mimicked by the administration of DG analogue (Dic8) into cultured neural stem cells (NSCs). Dic8 impaired proliferation and differentiation NSCs, whereas it could be recovered by PKCα inhibitor. Overall, this study demonstrates that Seipin deficiency leads to systemic lipid metabolism disorder, which impairs neurogenesis and olfactory memory. Adipose transplantation restores lipid metabolic homeostasis and neurogenesis via PKCα involved pathway. The present study paves a novel way to treat lipid metabolic dysregulation-induced neurological disorders

Lipodystrophy-associated Metabolic Disorders caused by Seipin deficiency lead to not only severe lipodystrophy but also neurological disorders. However, the underlying mechanism of Seipin deficiency-induced neuropathy is not well elucidated and the possible restorative strategy needs to be explored. In the present study, we investigated the systemic lipid metabolic abnormalities of Seipin knockout (KO) mice and their effect on adult neurogenesis in the subventricular zone (SVZ) and olfactory function. It was found that KO mice presented an ectopic accumulation of lipid in the lateral ventricle, accompanied by decreased neurogenesis in adult SVZ, diminished new neuron formation in the olfactory bulb, and impaired olfactory-related memory. Transcriptome analysis showed that the differentially expressed genes (DEGs) in SVZ tissues of adult KO mice were significantly enriched in biological processes related to lipid metabolism. Mass spectrometry imaging showed that the levels of glycerophospholipid, diglyceride and ceramide were significantly increased. In the restorative study, we found that subcutaneous adipose tissue transplantation (AT) rescued the abnormality of peripheral metabolism in KO mice and ameliorated the ectopic lipid accumulation in SVZ, concomitant with restoration of the SVZ neurogenesis and olfactory function. Mechanistically, PKCα was the potential mediator of lipid dysregulation-induced phenotypes. In the brain tissue of KO mice, PKCα was upregulated, which could be mimicked by the administration of DG analogue (Dic8) into cultured neural stem cells (NSCs). Dic8 impaired proliferation and differentiation NSCs, whereas it could be recovered by PKCα inhibitor. Overall, this study demonstrates that Seipin deficiency leads to systemic lipid metabolism disorder, which impairs neurogenesis and olfactory memory. Adipose transplantation restores lipid metabolic homeostasis and neurogenesis via PKCα involved pathway. The present study paves a novel way to treat lipid metabolic dysregulation-induced neurological disorders.

Association of complement component 4 with neuroimmune abnormalities in the subventricular zone in schizophrenia and autism spectrum disorders

An early inflammatory insult is the most recognized risk factor associated with neurodevelopmental psychiatric disorders, even more so than genetic variants. Notably, complement component 4 (C4), a molecule involved in inflammatory responses, has been strongly associated with schizophrenia (SZ) and its role in other neurodevelopmental disorders, such as autism (ASD), is an area of active investigation. However, while C4 in SZ has been implicated in the context of synaptic pruning, little is known about its neuroinflammatory role. The subventricular zone (SVZ) is a region heavily involved in neurodevelopment and neuroimmune interactions through the lifespan; thus, it is a region wherein C4 may play a vital role in disease pathology. Using in situ hybridization with radioactive riboprobes and RNAscope, we identified robust astrocytic expression of C4 in the SVZ and in the septum pellucidum. C4 was also expressed in ependyma, neurons, and Ki67⁺ progenitor cells. Examination of mRNA levels showed elevated C4 in both ASD and SZ, with higher expression in SZ compared to controls. Targeted transcriptomic analysis of inflammatory pathways revealed a strong association of complement system genes with SZ, and to a lesser extent, ASD, as well as generalized immune dysregulation without a strong association with known infectious pathways. Analysis of differentially expressed genes (DEGs) showed that ASD DEGs were enriched in adaptive immune system functions such as Th cell differentiation, while SZ DEGs were enriched in innate immune system functions, including NF-κB and toll like receptor signaling. Moreover, the number of Ki67⁺ cells was significantly higher in ASD compared to SZ and controls. Taken together, these results support a role for C4 into inflammatory-neuroimmune dysregulation observed in SZ and ASD pathology.

Molecular mechanisms and physiological functions of autophagy in kidney diseases

Autophagy is a highly conserved cellular progress for the degradation of cytoplasmic contents including micromolecules, misfolded proteins, and damaged organelles that has recently captured attention in kidney diseases. Basal autophagy plays a pivotal role in maintaining cell survival and kidney homeostasis. Accordingly, dysregulation of autophagy has implicated in the pathologies of kidney diseases. In this review, we summarize the multifaceted role of autophagy in kidney aging, maladaptive repair, tubulointerstitial fibrosis and discuss autophagy-related drugs in kidney diseases. However, uncertainty still remains as to the precise mechanisms of autophagy in kidney diseases. Further research is needed to clarify the accurate molecular mechanism of autophagy in kidney diseases, which will facilitate the discovery of a promising strategy for the prevention and treatment of kidney diseases.

Coagulation and complement: Key innate defense participants in a seamless web

In 1969, Dr. Oscar Ratnoff, a pioneer in delineating the mechanisms by which coagulation is activated and complement is regulated, wrote, “In the study of biological processes, the accumulation of information is often accelerated by a narrow point of view. The fastest way to investigate the body’s defenses against injury is to look individually at such isolated questions as how the blood clots or how complement works. We must constantly remind ourselves that such distinctions are man-made. In life, as in the legal cliché, the devices through which the body protects itself form a seamless web, unwrinkled by our artificialities.” Our aim in this review, is to highlight the critical molecular and cellular interactions between coagulation and complement, and how these two major component proteolytic pathways contribute to the seamless web of innate mechanisms that the body uses to protect itself from injury, invading pathogens and foreign surfaces.

Cooperation of Striatin 3 and MAP4K4 promotes growth and tissue invasion

MAP4K4 is associated with increased motility and reduced proliferation in tumor cells, but the regulation of this dichotomous functionality remained elusive. We find that MAP4K4 interacts with striatin 3 and 4 (STRN3/4) and that STRN3 and MAP4K4 exert opposing functions in Hippo signaling and clonal growth. However, depletion of either STRN3 or MAP4K4 in medulloblastoma cells reduces invasion, and loss of both proteins abrogates tumor cell growth in the cerebellar tissue. Mechanistically, STRN3 couples MAP4K4 to the protein phosphatase 2A, which inactivates growth repressing activities of MAP4K4. In parallel, STRN3 enables growth factor-induced PKCθ activation and direct phosphorylation of VASP_S157 by MAP4K4, which both are necessary for efficient cell invasion. VASP_S157 directed activity of MAP4K4 and STRN3 requires the CNH domain of MAP4K4, which mediates its interaction with striatins. Thus, STRN3 is a master regulator of MAP4K4 function, and disruption of its cooperation with MAP4K4 reactivates Hippo signaling and represses tissue invasion in medulloblastoma.

Analysis of the MAP4K4-STRN3 cooperation in medulloblastoma reveals its opposing regulation of Hippo activation and tissue invasion in cancer.

Efp/TRIM25 and Its Related Protein, TRIM47, in Hormone-Dependent Cancers

Increasing attention has been paid to the biological roles of tripartite motif-containing (TRIM) family proteins, which typically function as E3 ubiquitin ligases. Estrogen-responsive finger protein (Efp), a member of the TRIM family proteins, also known as TRIM25, was originally identified as a protein induced by estrogen and plays critical roles in promoting endocrine-related cancers, including breast cancer, endometrial cancer, and prostate cancer. The pathophysiological importance of Efp made us interested in the roles of other TRIM family proteins that share a similar structure with Efp. Based on a phylogenetic analysis of the C-terminal region of TRIM family proteins, we focused on TRIM47 as a protein belonging to the same branch as Efp. TRIM47 is a poor prognostic factor in both breast cancer and prostate cancer. Atypical lysine-27-like poly-ubiquitination was involved in the underlying mechanism causing endocrine resistance in breast cancer. We also discuss the functions of Efp and TRIM47 in other types of cancers and innate immunity by introducing substrates the are modified by poly-ubiquitination.

The Complement System, Aging, and Aging-Related Diseases

The complement system is a part of the immune system and consists of multiple complement components with biological functions such as defense against pathogens and immunomodulation. The complement system has three activation pathways: the classical pathway, the lectin pathway, and the alternative pathway. Increasing evidence indicates that the complement system plays a role in aging. Complement plays a role in inflammatory processes, metabolism, apoptosis, mitochondrial function, and Wnt signaling pathways. In addition, the complement system plays a significant role in aging-related diseases, including Alzheimer’s disease, age-related macular degeneration, and osteoarthritis. However, the effect of complement on aging and aging-related diseases is still unclear. Thus, a better understanding of the potential relationship between complement, aging, and aging-related diseases will provide molecular targets for treating aging, while focusing on the balance of complement in during treatment. Inhibition of a single component does not result in a good outcome. In this review, we discussed the research progress and effects of complement in aging and aging-related diseases.

Association between RAC1 gene variation, redox homeostasis and type 2 diabetes mellitus

BACKGROUND

Increased production of reactive oxygen species (ROS) and oxidative stress are known to play a key role in the pathogenesis of type 2 diabetes (T2D); however, the relationship between genes encoding a multi-subunit ROS-generated enzyme NADPH oxidase and disease susceptibility remains unexplored.

AIMS

The present pilot study investigated whether single-nucleotide polymorphisms (SNP) at the RAC1 gene (Rac family small GTPase 1), a molecular switcher of NADPH oxidase, are associated with the risk of T2D, glucose metabolism and redox homeostasis.

MATERIALS & METHODS

DNA samples from 3206 unrelated Russian subjects (1579 T2D patients and 1627 controls) were genotyped for six common SNPs rs4724800, rs7784465, rs10951982, rs10238136, rs836478 and rs9374 of RAC1 using the MassArray-4 system.

RESULTS

SNP rs7784465 was associated with an increased risk of T2D (p = .0003), and significant differences in the RAC1 haplotypes occurred between the cases and controls (p = .005). Seventeen combinations of RAC1 genotypes showed significant associations with T2D risk (FDR <0.05). Associations of RAC1 polymorphisms with T2D were modified by environmental factors such as sedentary lifestyle, psychological stresses, a dietary deficit of fresh fruits/vegetables and increased carbohydrate intake. RAC1 polymorphisms were associated with biochemical parameters in diabetics: rs7784465 (p = .015) and rs836478 (p = .028) with increased glycated haemoglobin, rs836478 (p = .005) with increased fasting blood glucose, oxidized glutathione (p = .012) and uric acid (p = .034). Haplotype rs4724800A-rs7784465C-rs10951982G-rs10238136A-rs836478C-rs9374G was strongly associated with increased levels of hydrogen peroxide (p < .0001).

CONCLUSION

Thus, polymorphisms in the RAC1 gene represent novel genetic markers of type 2 diabetes, and their link with glucose metabolism and disease pathogenesis is associated with the changes in redox homeostasis.