NJITOYAP NFOMBOUOT Philipe Herman

Mr. NJITOYAP NFOMBOUOT Philipe Herman

orcid

Research Focus & Metrics

Academic Career Length

3Years (2024-Present)

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

Representative Publications

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10 August 2024 in Pharmaceutical Science Advances
Verified
Journal Article
Open access
AKArnaud Fondjo Kouam
Arnaud Fondjo Kouam
INIbrahim Njingou
Ibrahim Njingou
NMNina Jeannette Pekam Magoudjou
Nina Jeannette Pekam Magoudjou
HNHamed Bechir Ngoumbe
Hamed Bechir Ngoumbe
NHNJITOYAP NFOMBOUOT Philipe Herman
NJITOYAP NFOMBOUOT Philipe Herman
PMPaul F. Moundipa
Paul F. Moundipa
The use of N-acetylcysteine against acetaminophen(APAP)-induced hepatotoxicity, a leading cause of liver injury, has several drawbacks, including short therapeutic windows. Khaya grandifoliola (Meliaceae) has been traditionally used to manage liver-related diseases, and many reports have confirmed its hepatoprotective properties. However, its therapeutic potential as an antidote against APAP-induced hepatotoxicity has yet to be proven in a clinically relevant model. This study aimed to verify the efficacy of delayed treatment with the hydroethanolic extract of K. grandifoliola (KgE) in suppressing the early injury phase of APAP pathophysiology. KgE was analyzed using HPLC/UV. Acute oral toxicity tests were conducted in mice to determine the therapeutic dose of KgE. Mice were treated with 300 ​mg/kg APAP; 1h and 12h later, they were treated with either predetermined doses of KgE or 20 ​mg/kg c-Jun N-Terminal Kinase (JNK) inhibitor SP600125, which served as a reference antidote. At 6h and 24h after APAP treatment, the parameters of liver damage and mitochondrial dysfunction, phosphorylation of JNK, and mitochondrial translocation were assessed. KgE at a dose of 5000 ​mg/kg was safe for mice. Accordingly, 100, 200, and 400 ​mg/kg were selected as curative treatments. Delayed administration of KgE reversed the histopathological changes in the liver, inhibited serum levels of alanine aminotransferase, reduced the liver content of nitric oxide and malondialdehyde, and restored hepatic glutathione pools and superoxide dismutase and catalase activities in APAP-intoxicated mice. Moreover, KgE prevented APAP-induced JNK phosphorylation and p-JNK mitochondrial translocation and rescued the activities of mitochondrial enzyme complexes II and V. HPLC/UV analysis revealed the presence of gallic acid, Quercetin and Silibinin, with retention times of 3.77, 11.63 and 11.95 ​min as the major active ingredients present in KgE. Our findings demonstrate that post-treatment with KgE protects the mouse liver from APAP-hepatotoxicity through the inhibition of JNK activation and mitochondrial dysfunction.

19 February 2026 in Microbes & Immunity
Verified
Journal Article
Open access
PDF file
AKArnaud Fondjo Kouam
Arnaud Fondjo Kouam
NHNJITOYAP NFOMBOUOT Philipe Herman
NJITOYAP NFOMBOUOT Philipe Herman
FSFredy Brice Nemg Simo
Fredy Brice Nemg Simo
Cromwel Tepap ZemnouCromwel Tepap Zemnou
Cromwel Tepap Zemnou
KKKerinyuy Juliene Kongnyuy
Kerinyuy Juliene Kongnyuy
PMPaul F. Moundipa
Paul F. Moundipa
Hepatitis E virus (HEV) is a major zoonotic pathogen, and pigs are an important reservoir. Serology for anti-HEV antibodies poorly reflects active infection, while reverse transcription polymerase chain reaction (RT-PCR) is sensitive but not always feasible for large-scale surveillance. This study aimed to develop an immunoglobulin Y (IgY)-based sandwich enzyme-linked immunosorbent assay (ELISA) for direct detection of HEV antigen (HEV-Ag). An antigenic epitope from the HEV open reading frame 2 capsid protein was identified in silico, synthesized, and used to immunize laying hens; IgY was purified from egg yolk and characterized by sodium dodecyl sulfate–polyacrylamide gel electrophoresis. An in-house sandwich ELISA was subsequently developed using the anti-HEV IgY antibodies. Its diagnostic performance was evaluated against RT-PCR using 350 field-collected pig serum samples and compared with commercial anti-HEV IgG and IgM ELISA kits. Immunization yielded high-purity IgY antibodies, with antigen-specific antibody kinetics showing a significant increase in specific immunoreactivity from week 4 onward and peak sensitivity at weeks 6–8 post-immunization. The anti-HEV IgY showed high specificity, with no cross-reactivity observed against a heterologous antigen (HBsAg). The optimized sandwich ELISA detected HEV-Ag with a sensitivity of 95.4% and a specificity of 100% relative to RT-PCR. The prevalence of HEV-Ag was 17.7% (62/350), which was not significantly different from RT-PCR (18.6%, 65/350; p=0.250). In contrast, commercial IgG and IgM ELISAs showed high seroprevalence rates (34.9% and 28.3%, respectively) but exhibited significant discrepancies with RT-PCR (p<0.0001), indicating limited utility for identifying active infection. Overall, the developed IgY-based sandwich ELISA demonstrated high diagnostic performance for detecting active HEV infection. This assay represents a viable alternative to RT-PCR for large-scale surveillance, particularly in resource-constrained settings, and may contribute to improved control of zoonotic HEV transmission.