Biology subjects

Wruck, W.

Publications and source records attributed to Wruck, W..

At least 19 recordsLinked to original sources

bioRxiv2026

Meta-analyses of the NEPTUNE dataset related to high and low risk FSGS and cellular APOL1 models identifies Calcium signalling, mTOR signaling and inflammation-associated pathways as operative in APOL1-mediated kidney disease.

BackgroundThe variants G1 and G2 within the APOL1 gene confer a higher risk of APOL1-mediated kidney disease (AMKD) whilst associated with an evolutionary advantage against trypanosome-mediated sleeping sickness. MethodsIn this study, we analysed transcriptome data of kidney biopsies from FSGS patients with the APOL1 high-risk (HR) and low-risk (LR) variants and compared it to cellular models based on patient-specific podocytes, HEK cells with engineered over-expressing HR variants and HR variant single-cell-RNA-seq data from kidney organoids. ResultsWe identified a signature of up- and down-regulated genes between biopsies from FSGS patients with APOL1 HR and LR variants. The up-regulated genes are functionally annotated to be associated with Calcium and mTOR signaling, whilst the down-regulated genes with inflammatory and immune response pathways. These pathways were confirmed by comparing with cellular models. Analysis of small molecules reverting the IFN-{gamma} stimulated gene expression to the non-stimulated gene expression in genome-edited APOL-G1 kidney organoids revealed several putative candidates such as the mTOR inhibitor AZD-2014. ConclusionWe have unveiled a signature of up- and down-regulated genes between APOL1 HR and LR kidney biopsies which could be assigned as associated with Calcium and mTOR signaling and down-regulated immune response.

molecular biology↗

bioRxiv2026

SAHA increases chaperone expression and reduces Z-alpha-1-antitrypsin polymers in a patient specific iPSC-based liver model for alpha-1-antitrypsin deficiency

The most severe phenotype of alpha-1-antitrypsin deficiency (AATD) is caused by the Z-mutation within the SERPINA1 gene. The Glu342Lys substitution causes misfolding and polymerisation of the alpha-1-antitrypsin (AAT) protein, its accumulation in the ER and increases the susceptibility of hepatocytes towards ER-stress. Here, we present an induced pluripotent stem cell (iPSC)-based hepatic model to study AATD. We demonstrate that iPSCs from AATD patients differentiate equally well to hepatocyte-like cells (HLCs) as control iPSCs. We detected ZAAT polymers in patient-derived HLCs which could be reduced by SAHA or CBZ treatment. Transcriptome analyses revealed major differences in metabolism and signalling between control and AATD HLCs and indicated increased stress levels affecting intracellular organelles. Importantly, the transcriptomes of control and patient-derived cells separated into distinct clusters with respect to the expression of Heat-shock protein (HSP) encoding genes. SAHA treatment increased expression of various HSPs which might contribute towards reduced ZAAT polymers.

cell biology↗

bioRxiv2025

Human CSB-deficient iPSCs exhibit impaired DNA damage repair and stress responses following BPDE exposure in an early developmental model.

Maintenance of genome integrity is essential for normal human development, particularly during pre-gastrulation stages when rapid proliferation and intense transcriptional activity increase susceptibility to DNA damage. Environmental genotoxins such as benzo[a]pyrene (BaP), a widespread polycyclic aromatic hydrocarbon, and its reactive metabolite benzo[a]pyrene diol epoxide (BPDE) form bulky DNA adducts that interfere with replication and transcription, thereby posing significant risks to embryonic genome stability. To examine how genetic defects in DNA repair influence these effects, we assessed human induced pluripotent stem cells (iPSCs) carrying pathogenic mutations in ERCC6 (encoding the Cockayne syndrome B, CSB, protein), a key component of transcription-coupled nucleotide excision repair. Pathogenic ERCC6 mutations result in Cockayne syndrome- a severe neurodevelopmental disorder characterized by growth failure, premature aging, and multisystemic degeneration, thus underscoring the essential developmental functions of CSB. Exposure of healthy and CSB-deficient patient derived iPSCs to BPDE revealed impaired proliferation, persistent accumulation of DNA damage and defective checkpoint activation in CSB-deficient lines. Although the levels of key pluripotency-regulating proteins such as OCT4 and NANOG remained unaltered, we observed altered levels of SOX2 and p-SMAD1/5 signaling thus implying that unrepaired DNA damage can perturb developmental-associated signaling pathways and biological processes. Transcriptomic profiling revealed broad suppression of DNA repair and cell-cycle pathways together with activation of p53-, TNF-, and MAPK/JNK-mediated stress responses in CSB-deficient lines. Failure to induce anti-oxidant defenses, including SOD2 and IDO, further contributed to oxidative imbalance and incomplete apoptotic clearance. These findings demonstrate that CSB function is essential for coupling DNA repair with transcriptional recovery and redox homeostasis in pluripotent cells. Loss of CSB destabilizes the genome stability under genotoxic stress, providing a mechanistic basis for developmental toxicity of environmental polycyclic aromatic hydrocarbons and underscoring the importance of considering genetic susceptibility in developmental toxicology risk assessment.

developmental biology↗

bioRxiv2025

Modelling APOL1-mediated kidney inflammation and fibrosis using a partially reprogrammed urine derived SIX2-positive renal progenitor cell line.

BackgroundCKD affects approximately 850 million people worldwide and is a leading cause of mortality. Podocytes, cells in the kidney are terminally differentiated and incapable of division in vivo making the establishment of primary cultures particularly challenging. The ability of cells to proliferate and avoid senescence is closely linked to telomere length. When telomere length becomes critically reduced, it results in cellular senescence. MethodsWe present the successful rejuvenation of a human SIX2-positive renal progenitor cell line derived from the urine of a 30-year-old West African male (UM30-OSN). To achieve partial reprogramming, plasmids expressing the Yamanaka factors OCT4, SOX2, NANOG, c-Myc, and KLF4 were employed. ResultsUM30-OSN expresses the pluripotency-associated marker SSEA4, renal stem cell markers such as SIX2, CD133 and CD24, determined by immunofluorescence, FACS and qPCR. Expression analysis revealed downregulation of senescence markers p21and p53 and upregulation of proliferation-associated genes PCNA, KI67 and TERT, confirming rejuvenation. Upon podocyte differentiation, UM30-OSN cells expressed podocyte-specific markers NPHS1, NPHS2, SYNPO and CD2AP. Comparative transcriptome analyses revealed a correlation co-efficiency (R2 = 0.88) with the immortal podocyte line AB 8/13. To demonstrate the usefulness of UM30-OSN to model APOL1-mediated kidney disease, we investigated the effects of Interferon-{gamma} (IFN-{gamma}) on UM30-OSN derived podocytes and evaluated the potential of the JAK1/JAK2 inhibitor Baricitinib to mitigate IFN-{gamma}-induced cellular responses. IFN-{gamma} stimulation resulting in increased phosphorylation of STAT1, activation of APOL1, upregulation of pro-inflammatory and fibrotic markers such as, IL-6, TGF-{beta}, Vimentin, Fibronectin, and morphological changes indicative of cell stress. Pre-treatment with Baricitinib effectively inhibited STAT1 phosphorylation, reduced expression of pro-inflammatory and fibrosis-associated genes, and preserved podocyte morphology. ConclusionGiven their robust proliferation capacity, UM30-OSN cells represent a valuable additional model for investigating kidney-associated diseases such the contribution of APOL1 high-risk variants to kidney injury and fibrosis.

molecular biology↗

bioRxiv2025

Human Urine-derived SIX2-positive renal progenitor cells improve kidney injury in an IRI mouse model

Cells with the characteristics of renal progenitor cells are shed in urine. The aim of this study was to investigate whether these SIX2-positive urine-derived renal progenitor cells (UdRPC) have therapeutic potential in treating or managing acute to chronic kidney injuries. Human UdRPC were obtained from a woman aged 35 years, expanded, and characterized in vitro and finally transplanted unilaterally under the renal capsule of mouse kidneys that had undergone ischemia reperfusion injury (IRI). Analyses of blood serum from the mice revealed that the transplanted human UdRPC transiently influenced the secretome of the animals by triggering the release of inflammatory and angiogenic factors. Of obvious therapeutic relevance, however, was the finding that the transplanted cells suppressed renal fibrosis resulting from IRI. The expression of genes linked to inflammation and chronic kidney disease was also reduced in mouse kidneys in the presence of UdRPC. Ultimately, the human UdRPC were able to alleviate the severity of the injury through the amelioration of fibrosis but were unable to restore complete kidney function within 21 days. Nevertheless, the findings of this study demonstrate a significant influence of transplanted UdRPC on kidney fibrosis after acute to chronic injury presumably via an altered secretome.

cell biology↗

bioRxiv2024

Investigating BPDE-induced embryonic toxicity employing hiPSC-based models

Benzo[a]pyrene diol epoxide (BPDE) is a metabolite of the environmental contaminant Benzo[a]pyrene- a byproduct of incomplete combustion of organic matter. BPDE reacts with DNA to form BPDE-DNA bulky adducts which if not removed can lead to mutations due to DNA base-pair substitutions. While the effects of BPDE on somatic cells are fairly well described, its effects on early human development are currently unknown. In this study, we investigated for the first time the effect of BPDE on human induced pluripotent stem cells (hiPSCs) and their differentiated neuroprogenitor cells (NPCs) as a model for early embryonic development. Furthermore, we compared hiPSCs and NPCs derived from cells of patients suffering from Nijmegen Breakage Syndrome (NBS), which is a chromosomal instability disorder characterized by defective DNA repair and increased risk of malignancies. Transcriptome analysis, coupled with protein content analysis employing immunostaining and Western blots, revealed that hiPSCs are more sensitive to BPDE exposure when compared to NPCs with an enhanced expression of several genes associated with p53-mediated DNA damage response, including DNA repair by lesion bypass, cell cycle checkpoints and extrinsic apoptosis. We also identified that cells from NBS patients showed less apoptotic response and a distinct p53 response than their healthy counterparts. This iPSC-based study enhances our meagre knowledge of the effects of BPDE on early human development in both healthy individuals and NBS patients. Furthermore, our model conforms with the 3Rs principle.

pharmacology and toxicology↗

bioRxiv2024

Inhibiting DPP4 activity protects hiPSC-derived steatotic HLCs by supporting fatty acid and purine metabolism and dampening inflammation

BackgroundMetabolic dysfunction-associated steatotic liver disease (MAFLD) has a high prevalence and high co-morbidity for other diseases. Due to the complexity of this multifactorial disease, therapy options are still rather limited. We employed an in vitro pluripotent stem cell-based model to decipher potential disease-associated molecular pathways and to study the mode of action of prospective drugs. Dipeptidyl peptidase 4 (DPP4) or Cluster of differentiation 26 (CD26) is involved in inflammation, infections, immune disorders, type 2 diabetes, kidney disease and cancer. MethodsWe induced the steatosis phenotype in human induced pluripotent stem cell (iPSC) derived hepatocyte-like cells (HLCs) by oleic acid (OA)-feeding and confirmed regulation of clinically relevant pathways by NGS-based global transcriptomic analyses. Analysis of the secretome of steatotic HLCs revealed DPP4 as a potential key mediator of the disease. To further elucidate its role in the development of MAFLD, we inhibited DPP4 activity with Vildagliptin (VILDA) and analyzed the global transcriptome changes as well as specific gene and protein expression of steatosis-associated genes with and without DPP4 inhibition. ResultsMAFLD-associated pathways such as PPAR- and TNF signaling were differentially regulated in hiPSC-derived steatotic HLCs. We found increased hepatic DPP4 activity and secretion upon OA. Gene expression of fatty acid and purine metabolism and inflammation-associated pathways were regulated upon DPP4 inhibition. ConclusionsOur HLC-model confirmed association of DPP4 with metabolism and inflammation which foster the development of MAFLD. Inhibiting DPP4 with VILDA partially relieved the steatotic phenotype on a global transcriptomic level. Impact and implicationsGiven the difficulties of identifying suitable anti-MAFLD drugs, novel model systems are urgently needed. Our in vitro HLC-model reproduced DPP4-dependent aspects of the disease and responded positively to Vildagliptin treatment. Further elucidation of the role of DPP4 in the etiology of MAFLD and other diseases is warranted.

cell biology↗

bioRxiv2024

Single cell data enables dissecting cell types present in bulk transcriptome data

The quality of organoid models can be assessed by single-cell-RNA-sequencing (scRNA-seq) but often only bulk transcriptome data is available. Here we present a pipeline for the analysis of scRNA-seq data and subsequent "deconvolution", which is a method for estimating cell type fractions in bulk transcriptome data based on expression profiles and cell types found in scRNA-seq data derived from biopsies. We applied this pipeline on bulk iPSC-derived kidney and brain organoid transcriptome data to identify cell types employing two scRNA-seq kidney datasets and one brain dataset. Relevant cells present in kidney (eg. proximal tubules, distal convoluted tubules and podocytes) and brain (eg. neurons, astrocytes, oligodendrocytes and microglia) with obligatory endothelial and immune-related cells were identified. We anticipate that this pipeline will also enable estimation of cell type fractions in organoids of other tissues.

bioinformatics↗

bioRxiv2024

Up-regulated transcriptional regulators in mutant RAS gene signatures: a time-resolved multi-omics study in generic epithelial cell models

The expression of mutated RAS genes drives extensive transcriptome alterations. Perturbation experiments have shown that the transcriptional responses to downstream effector pathways are partially unique and non-overlapping, suggesting a modular organization of the RAS-driven expression program. However, the relationship between individual deregulated transcription factors and the entire cancer cell-specific genetic program is poorly understood. To identify potential regulators of the RAS/MAPK-dependent fraction of the genetic program, we monitored transcriptome and proteome changes following conditional, time-resolved expression of mutant HRASG12V in human epithelial cells during neoplastic conversion. High mobility group AT hook2 (HMGA2), an architectural chromatin modulating protein and oncofetal tumour marker, was recovered as the earliest upregulated transcription factor. Knock-down of HMGA2 reverted anchorage-independent growth and epithelial-mesenchymal transition not only in HRAS-transformed cells but also in an independent, KRASG12V-driven rat epithelial model. Moreover, HMGA2 silencing reverted the deregulated expression of 60% of RAS-responsive target genes. These features qualify HMGA2 as a master regulator of mutant RAS-driven expression patterns. The delayed deregulation of FOSL1, ZEB1 and other transcription factors with known oncogenic activity suggests that HMGA2 acts in concert with a network of regulatory factors to trigger full neoplastic conversion. Although transcription factors are considered difficult to drug, the central role of HMGA2 in the transcription factor network as well as its relevance for cancer prognosis has motivated attempts to block its function using small molecular weight compounds. The further development of direct HMGA2 antagonists may prove useful in cancer cells that have developed resistance to signalling chain inhibition.

cancer biology↗

bioRxiv2023

Cockayne syndrome patient iPSC-derived brain organoids and neurospheres show early transcriptional dysregulation of biological processes associated with brain development and metabolism.

Cockayne syndrome is a rare hereditary autosomal recessive disorder characterized by diverse neurological afflictions. However, little is known about the cerebral development in CS patients. We generated neurospheres and cerebral organoids utilizing Cockayne Syndrome B Protein (CSB) deficient induced pluripotent stem cells derived from two patients with distinct severity levels of CS and healthy controls. The transcriptome of both developmental timepoints was explored using RNA-Seq and bioinformatic analysis to identify dysregulated biological processes common to both CS patients in comparison to control. CSB-deficient neurospheres displayed upregulation of VEGFA-VEGFR2 signaling pathway, Vesicle-Mediated transport and head development. CSB-deficient cerebral organoids exhibited downregulation of brain development, neuron projection development and synaptic signalling. We further identified upregulation of Steroid Biosynthesis as common to both timepoints, in particular upregulation of the Cholesterol Biosynthesis branch. Our results provide insights into the neurodevelopmental dysregulation in CS patients and strengthen the theory, that CS is not only a neurodegenerative, but also a neurodevelopmental disorder.

neuroscience↗

bioRxiv2023

Unconjugated bilirubin induces neuro-inflammation in an induced pluripotent stem cell-derived cortical organoid model of Crigler Najjar Syndrome

Bilirubin-induced neurological damage (BIND), which is also known as Kernicterus, occurs as a consequence of defects in the bilirubin conjugation machinery, thus resulting in unconjugated bilirubin (UCB) to cross the blood-brain barrier (BBB) and accumulation. Severe hyperbilirubinemia can be caused by a mutation within the UGT1A1 encoding gene. This mutation has a direct contribution towards bilirubin conjugation leading to Kernicterus as a symptom of Crigler Najjar Syndromes (CNS1, CNS2) and Gilbert syndrome, which results in permanent neurological sequelae. In this comparative study, we used human induced pluripotent stem cells (hiPSCs)-derived 3D-brain organoids to model BIND in vitro and unveil the molecular basis of the detrimental effects of UCB in the developing human brain. hiPSC-derived from healthy and CNS patients were differentiated into day-20 brain organoids, these were then stimulated with 200nM UCB. Analyses at 24- and 72-hrs post-treatment point at UCB-induced neuro-inflammation in both cell lines. Transcriptome and associated KEGG and Gene Ontology analyses unveiled activation of distinct inflammatory pathways such as cytokine-cytokine receptor interaction, MAPK signaling, calcium signaling, NF{kappa}B activation. Furthermore, both mRNA expression and secretome analysis confirmed an upregulation of pro-inflammatory cytokines such as IL6 and IL8 upon UCB stimulation. In summary, this novel study has provided insights into how a human iPSC-derived 3D-brain organoid model can serve as a prospective platform for studying the etiology of BIND-Kernicterus.

neuroscience↗

bioRxiv2023

Cytokines in the Urine of AKI patients regulate TP53 and SIRT1 and can be used as biomarkers for the early detection of AKI

Acute kidney injury (AKI) is a major kidney disease with a poor clinical outcome. It is a common complication with an incidence of 10-15% of patients admitted to hospital. This rate even increases for patients who are admitted to the intensive care unit with an incidence of >50%. AKI is characterized by a rapid increase in serum creatinine, decrease in urine output, or both. Associated Symptoms include feeling sick or being sick, diarrhoea, dehydration, decreased urine output-although occasionally urine output remains normal, fluid retention-causing swelling in the legs or ankles, shortness of breath, fatigue and nausea. However, sometimes acute kidney injury causes no signs or symptoms and is detected by lab tests. Therefore, an urgent demand for non-invasive biomarkers for early detection of AKI are highly desirable. This might enable the prevention of the progression from AKI to CKD. In this study, we analysed the secretome of urine of an AKI patient cohort employing a kidney-biomarker cytokine assay. Based on these results we suggest, ADIPOQ, EGF and SERPIN3A as potential biomarkers, which might be able to detect AKI as soon as 24 h post-surgery. For the later stages, common biomarkers for the detection of AKI in both male and female patients we suggest, VEGF, SERPIN3A, TNFSF12, ANPEP, CXCL1, REN, CLU and PLAU. These markers in combination might present a robust strategy to identify the development of AKI as early as 24h or 72h post-surgery. Furthermore, we evaluated the effect of patient and healthy urine on human podocyte cells. We conclude that cytokines in the urine of AKI patients trigger processes which are needed to repair the damaged nephron and activate TP53 and SIRT1 to maintain the balance between proliferation, angiogenesis, and cell cycle arrest. In conclusion, the Renin-Angiotensin pathway seems to have major implications.

molecular biology↗

bioRxiv2022

Urine-based detection of biomarkers indicative of chronic kidney disease in a patient cohort from Ghana

Chronic kidney disease (CKD) is a global health burden with a continuously increasing prevalence associated with an increasing incidence of diabetes and hypertension in aging populations. The CKD definition of a more than three months lasting low glomerular filtration rate (GFR) or other renal impairments including proteinuria implies that multiple factors may contribute to the disease. While there are indications of ethnic differences it is hard to disentangle these from confounding social factors. Usually, CKD is detected in later stages of the disease when irreversible renal damage has already occurred, thus suggesting a need for early non-invasive diagnostic markers. In this study, we explored the urine secretome of a CKD patient cohort from Ghana employing a kidney-injury and a more general cytokine assay. We identified panels of kidney-specific cytokine markers which were also gender-specific and a panel of gender-independent cytokine markers. The gender-specific markers are IL10 and MME for male and CLU, RETN, AGER, EGFR and VEGFA for female. The gender-independent cytokine markers were APOA1, ANGPT2, C5, CFD, GH1, ICAM1, IGFBP2, IL8, KLK4, MMP9 and SPP1 (up-regulated) and FLT3LG, CSF1, PDGFA, RETN and VEGFA (down-regulated). APOA1 - the major component of HDL particles - was up-regulated in Ghanaian CKD patients and its co-occurrence with APOL1 in a subpopulation of HDL particles may point to specific CKD-predisposing APOL1 haplotypes in patients of African descent - this however needs further investigation. The identified panels may lay down the foundation for CKD-biomarker assays to be confirmed in further studies with a larger cohort of patients.

molecular biology↗

bioRxiv2022

JNK signalling regulates self-renewal of proliferative urine-derived renal progenitor cells via inhibition of ferroptosis

With a global increase in chronic kidney disease patients, alternatives to dialysis and organ transplantation are needed. Stem cell-based therapies could be one possibility to treat chronic kidney disease. Here, we used multipotent urine-derived renal progenitor cells (UdRPCs) to study nephrogenesis. UdRPCs treated with the JNK inhibitor-AEG3482, displayed decreased proliferation and downregulated transcription of cell cycle-associated genes as well as the kidney progenitor markers -SIX2, CITED1, and SALL1. In addition, levels of activated SMAD2/3, which is associated with the maintenance of self-renewal in UdRPCs, were decreased. JNK inhibition resulted in less efficient oxidative phosphorylation and more lipid peroxidation via ferroptosis-an iron-dependent non-apoptotic cell death pathway linked to various forms of kidney disease. Our study reveals the importance of JNK signalling in maintaining self-renewal as well as protection against ferroptosis in SIX2-positive UdRPCs. We propose that UdRPCs can be used for modelling ferroptosis-induced kidney diseases.

cell biology↗

bioRxiv2022

Gene expression studies of WT1 mutant Wilms tumor cell lines in the frame work of published kidney development data reveals their early stem cell origin

In order to get a better insight into the timing of WT1 mutant Wilms tumor development, we compared the gene expression profiles of nine established WT1 mutant Wilms tumor cell lines with published data from different kidney cell types during development. Publications describing genes expressed in nephrogenic precursor cells, ureteric bud cells, more mature nephrogenic epithelial cells and interstitial cell types were used. These studies uncovered that the WT1 mutant Wilms tumor cells lines express genes from the earliest nephrogenic progenitor cells, as well as from more differentiated nephron cells with the highest expression from the stromal/interstitial compartment. The expression of genes from all cell compartments points to an early developmental origin of the tumor in a common stem cell. Although variability of the expression of specific genes was evident between the cell lines the overall expression pattern was very similar. This is likely dependent on their different genetic backgrounds with distinct WT1 mutations and the absence/presence of mutant CTNNB1.

cancer biology↗

bioRxiv2022

Derivation of the immortalized cell line-UM51-PrePodo-hTERT and its responsiveness to Angiotensin II and activation of RAAS

Recent demographic studies predict there will be a considerable increase of elderly people within the next decades. Aging has been recognized as one of the main risk factors of the worlds most prevalent diseases, including neurodegenerative disorders, cancer, cardiovascular disease, and metabolic disease. During the process of aging a gradual loss of tissue volume and organ function is observed, which is partially caused by replicative senescence. The capacity of cellular proliferation and replicative senescence is tightly regulated by their telomere length. When the telomere length with progressive cell division is critically shortened, the cell becomes proliferative arrested and DNA damage response and cellular senescence are triggered. At this time point the so called "Hayflick limit" is attained. Podocytes are a cell type that is found in the kidney glomerulus where they have major implications in blood filtration. Mature podocytes are terminal differentiated cells that are unable to undergo cell division in vivo. For this reason, the establishment of podocyte cell cultures has been very challenging. In our present study, we present the successful immortalization of a human podocyte progenitor cell line, of which the primary cell cells were isolated directly from the urine of a 51-year-old male. The immortalized cell line has been cultured over the course of one year ([~]100 passages) with high proliferation capacity, while still endowed with contact inhibition and P53 expression and activation. Furthermore, by immunofluorescent-based expression and quantitative Real-Time PCR for the podocyte markers NPHS1, SYNPO and WT1 we confirmed the differentiation capacity of the immortalized cells. Finally, we evaluated and confirmed the responsiveness of the immortalized cells on the main mediator Angiotensin II (ANGII) of the renin-angiotensin-system (RAS). Elevated levels of ANGII have been identified as a main risk factor for the initiation and progression of chronic kidney disease (CKD). CKD is characterized by an impairment of podocyte function and subsequently podocyte apoptosis. As a major risk factor for patients to develop CKD, diabetes, hypertension, heart disease and stroke have been recognized - all of which show increased incidence in elderly people. In conclusion, we have shown that it is possible to by-pass cellular replicative senescence (Hayflicks limit) by TERT-driven immortalization of human urine-derived pre-podocyte cells from a 51-year-old African male.

cell biology↗

bioRxiv2021

Inflammation and Cellular Stress Induced Neurological Sequelae of Plasmodium falciparum Malaria

BackgroundMalaria caused by Plasmodium falciparum results in severe complications including cerebral malaria (CM) especially in children. While the majority of falciparum malaria survivors make a full recovery, there are reports of some patients ending up with neurological sequelae. MethodsWe performed an analysis of pooled transcriptome data of whole blood samples derived from two studies involving various Plasmodium falciparum infections, comprising mild malaria (MM), non-cerebral severe malaria (NCM) and CM. Pathways and gene ontologies (GOs) elevated in the distinct falciparum infections were identified. ResultsContrary to other research findings, our analysis showed MM share similar biological processes with cancer and neurodegenerative diseases, NCM is associated with drug resistance and glutathione metabolism and CM is correlated with endocannabinoid signaling and non-alcoholic fatty liver disease (NAFLD). GO revealed the terms biogenesis, DNA damage response and IL-10 production in MM, down-regulation of cytoskeletal organization and amyloid-beta clearance in NCM and aberrant signaling, neutrophil degranulation and gene repression in CM. Differential gene expression analysis between CM and NCM showed the up-regulation of neutrophil activation and response to herbicides while regulation of axon diameter was down-regulated in CM. ConclusionsThe results of this study have demonstrated that the deleterious effect of falciparum malaria on the brain may not be limited to CM and NCM alone but also MM. However, the severity of neurological deficit in CM might be due to the down-regulation of various genes involved in cellular function through transcriptional repression, axonal dysfunction, dysregulation of signaling pathways and neurodegeneration as a result of inflammation and cellular stress. We anticipate that our data might form the basis for future hypothesis-driven malaria research.

molecular biology↗

bioRxiv2021

Investigation of Thyroid Hormone Associated Gene-Regulatory Networks during Hepatogenesis using an Induced Pluripotent Stem Cell based Model

Currently, the only treatment of end-stage liver diseases is liver transplantation. The worldwide shortage of donor organs and the high number of patients suffering from end-stage liver diseases, require alternative treatment approaches. Therefore, the generation of hepatocyte-like cells (HLCs) derived from induced pluripotent stem cells (iPSCs) is a promising treatment option. HLCs are suitable for patient-specific drug screening, disease modeling and regenerative medicine. So far, they are immature and resemble the fetal state. In this study, we employed the combined thyroid hormones triiodo-L-thyronine (T3) and L-thyroxine (T4) to drive HLCs towards maturation. HLCs expressed the maturation markers ALBUMIN (ALB), ALPHA-1 ANTITRYPSIN (A1AT), CYTOCHROME P450 3A4 (CYP3A4) and TRANSTHYRETIN (TTR). Remarkably, stimulation with T3 and T4 slightly reduced the expression of the fetal marker CYTOCHROME P450 3A7 (CYP3A7) and had an even more pronounced effect on ALPHA-FETOPROTEIN (AFP) levels. Comparative transcriptome and associated pathways in unstimulated and T3 and T4 stimulated HLCs revealed regulated expression of numerous genes within for example the peroxisome proliferator-activated receptor (PPAR), transforming growth factor beta (TGF-{beta}), mitogen-activated protein kinase/extracellular-signal-regulated kinase (MAPK/ERK) signaling pathways and thyroid hormone synthesis. We propose the inclusion of combined T3 andT4 in HLC differentiation protocols to enhance maturation and therefore provide additional improvement in their applications in drug screening and disease modeling.

developmental biology↗