Shamim Wanjiku Osata

Dr. Shamim Wanjiku Osata

orcid

Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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3 October 2024 in Pathogens
Verified
Journal Article
Open access
PDF file
COClinton Odhiambo Onyango
Clinton Odhiambo Onyango
SASAMUEL B. ANYONA
SAMUEL B. ANYONA
IHIVY HURWITZ
IVY HURWITZ
EREvans Raballah
Evans Raballah
SWSharley A. Wasena
Sharley A. Wasena
DPDouglas J Perkins
Douglas J Perkins
Severe malarial anemia (SMA, Hb < 6.0 g/dL) is a leading cause of childhood morbidity and mortality in holoendemic Plasmodium falciparum transmission zones. This study explored the entire expressed human transcriptome in whole blood from 66 Kenyan children with non-SMA (Hb ≥ 6.0 g/dL, n = 41) and SMA (n = 25), focusing on host immune response networks. RNA-seq analysis revealed 6862 differentially expressed genes, with equally distributed up-and down-regulated genes, indicating a complex host immune response. Deconvolution analyses uncovered leukocytic immune profiles indicative of a diminished antigenic response, reduced immune priming, and polarization toward cellular repair in SMA. Weighted gene co-expression network analysis revealed that immune-regulated processes are central molecular distinctions between non-SMA and SMA. A top dysregulated immune response signaling network in SMA was the HSP60-HSP70-TLR2/4 signaling pathway, indicating altered pathogen recognition, innate immune activation, stress responses, and antigen recognition. Validation with high-throughput gene expression from a separate cohort of Kenyan children (n = 50) with varying severities of malarial anemia (n = 38 non-SMA and n = 12 SMA) confirmed the RNA-seq findings. Proteomic analyses in 35 children with matched transcript and protein abundance (n = 19 non-SMA and n = 16 SMA) confirmed dysregulation in the HSP60-HSP70-TLR2/4 signaling pathway. Additionally, glutamine transporter and glutamine synthetase genes were differentially expressed, indicating altered glutamine metabolism in SMA. This comprehensive analysis underscores complex immune dysregulation and novel pathogenic features in SMA.

12 June 2024 in Nature Communications
Verified
Journal Article
Open access
PDF file
SASAMUEL B. ANYONA
SAMUEL B. ANYONA
QCQuiying Cheng
Quiying Cheng
SWSharley A. Wasena
Sharley A. Wasena
SOShamim Wanjiku Osata
Shamim Wanjiku Osata
YGYan Guo
Yan Guo
DPDouglas J Perkins
Douglas J Perkins
This study on severe malarial anemia (SMA: Hb < 6.0 g/dL), a leading global cause of childhood morbidity and mortality, compares the entire expressed whole blood host transcriptome between Kenyan children (3-48 mos.) with non-SMA (Hb ≥ 6.0 g/dL, n = 39) and SMA (n = 18). Differential expression analyses reveal 1403 up-regulated and 279 down-regulated transcripts in SMA, signifying impairments in host inflammasome activation, cell death, and innate immune and cellular stress responses. Immune cell profiling shows decreased memory responses, antigen presentation, and immediate pathogen clearance, suggesting an immature/improperly regulated immune response in SMA. Module repertoire analysis of blood-specific gene signatures identifies up-regulation of erythroid genes, enhanced neutrophil activation, and impaired inflammatory responses in SMA. Enrichment analyses converge on disruptions in cellular homeostasis and regulatory pathways for the ubiquitin-proteasome system, autophagy, and heme metabolism. Pathway analyses highlight activation in response to hypoxic conditions [Hypoxia Inducible Factor (HIF)−1 target and Reactive Oxygen Species (ROS) signaling] as a central theme in SMA. These signaling pathways are also top-ranking in protein abundance measures and a Ugandan SMA cohort with available transcriptomic data. Targeted RNA-Seq validation shows strong concordance with our entire expressed transcriptome data. These findings identify key molecular themes in SMA pathogenesis, offering potential targets for new malaria therapies.

13 November 2023 in bioRxiv
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Preprint
Open access
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UOUchechuckwu Chibuzo Ogbodo
Uchechuckwu Chibuzo Ogbodo
OEOjochenemi A. Enejoh
Ojochenemi A. Enejoh
COChinelo H. Okonkwo
Chinelo H. Okonkwo
PGPranavathiyani Gnanasekar
Pranavathiyani Gnanasekar
PGPauline W. Gachanja
Pauline W. Gachanja
OAOlaitan I. Awe
Olaitan I. Awe
Despite improved treatment options, colorectal cancer (CRC) remains a huge public health concern with a significant impact on affected individuals. Cell cycle dysregulation and overexpression of certain regulators and checkpoint activators are important recurring events in the progression of cancer. Cyclin-dependent kinase 1 (CDK1), a key regulator of the cell cycle component central to the uncontrolled proliferation of malignant cells, has been reportedly implicated in CRC. This study aimed to identify CDK1 inhibitors with potential for clinical drug research in CRC. Ten thousand (10,000) naturally occurring compounds were evaluated for their inhibitory efficacies against CDK1 through molecular docking studies. The stability of the lead compounds in complex with CDK1 was evaluated using molecular dynamics simulation for one thousand (1,000) nanoseconds. The top-scoring candidates’ ADME characteristics and drug-likeness were profiled using SwissADME. Four hit compounds namely spiraeoside, robinetin, 6-hydroxyluteolin, and quercetagetin were identified from molecular docking analysis to possess the least binding scores. Molecular dynamics simulation revealed that robinetin and 6-hydroxyluteolin complexes were stable within the binding pocket of the CDK1 protein. The findings from this study provide insight into novel candidates with specific inhibitory CDK1 activities that can be further investigated through animal testing, clinical trials, and drug development research for CRC treatment.

16 October 2026 in Research Square
Verified
Preprint
Open access
PDF file
DPDouglas J Perkins
Douglas J Perkins
COClinton Odhiambo Onyango
Clinton Odhiambo Onyango
SOShamim Wanjiku Osata
Shamim Wanjiku Osata
SWSharley A. Wasena
Sharley A. Wasena
IHIVY HURWITZ
IVY HURWITZ
QCQuiying Cheng
Quiying Cheng
Malaria remains a leading cause of childhood morbidity and mortality in sub-Saharan Africa, with severe malarial anemia (SMA; hemoglobin (Hb) < 6.0 g/dL) representing one of the life-threatening complications of Plasmodium falciparum infection. While limited studies have examined host transcriptional responses in SMA, parasite transcriptional adaptations remain unexplored. Here, we performed parasite transcriptomic profiling in the same cohort of Kenyan children under five years of age in whom we previously characterized host transcriptional responses to SMA, including children presenting with SMA (n = 20) or non-SMA malaria (n = 40). Differential expression analysis identified 566 P. falciparum genes associated with SMA, predominantly involving up-regulated transcripts linked to proteostasis, translational regulation, stress-response pathways, and metabolic remodeling. Transcriptomic deconvolution indicated greater trophozoite and schizont representation in SMA, with reduced ring-stage and gametocyte signatures. Weighted gene co-expression network analysis and protein-protein interaction network analysis identified coordinated transcriptional programs enriched for proteasomal degradation, ubiquitin-mediated protein turnover, chaperone activity, RNA processing, and metabolic adaptation. XGBoost-SHAP modeling identified a small subset of parasite genes that captured much of the transcriptomic signal, classifying SMA from non-SMA malaria. Collectively, these findings define a distinct parasite transcriptional landscape in SMA characterized by coordinated stress adaptation and metabolic flexibility, highlighting proteostasis-associated pathways for further therapeutic investigation.