James nyabuga Nyariki

Dr. James nyabuga Nyariki


Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

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

Representative Publications

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29 March 2022 in Saudi Journal of Biological Sciences
Verified
Journal Article
Open access
DNDouglas Ngatuni
Douglas Ngatuni
PWPeninah Wairagu
Peninah Wairagu
NJNgalla Jillani
Ngalla Jillani
AIAlfred Orina Isaac
Alfred Orina Isaac
JNJames nyabuga Nyariki
James nyabuga Nyariki
Glyphosate-based herbicides (GBH) are widely used worldwide. Their negative impact on human health is a matter of debate by regulatory bodies and the public. The present study sought to determine the impact of a GBH on the vital organs; and the potential protective effects of vitamin B12 (cyanocobalamin) supplementation. Sixty white Swiss mice were randomly assigned to five treatment groups, each containing twelve mice. Group one represented the normal control; Group two mice were treated with 375 mg/kg of GBH for 56 days; Group three mice received 10 mg/kg of cyanocobalamin for 56 days; Group four mice were administered with 375 mg/kg of GBH and 10 mg/kg cyanocobalamin for 56 days and Group five received 10 mg/kg cyanocobalamin first for 7 days, then continued thereafter co-administered together with 375 mg/kg of GBH for 56 days). Oral administration of GBH induced severe anemia in mice, which was attenuated by cyanocobalamin. Moreover, GBH resulted in a very significant alteration of platelets, WBCs, and its sub-types. Once again, cyanocobalamin stabilized the levels of platelets and WBCs in the presence of GBH. GBH-induced elevation of triglycerides and HDL was nullified by the administration of cyanocobalamin. Further studies showed evidence for GBH-induced inflammation represented by an imbalance in serum levels of the TNF-α: IL-10 and IFN-γ ratios. The GBH severely depleted GSH levels in the liver. A GBH-induced rise in GSH in the kidney, lungs and brain was noted; and is an indicator of antioxidant capacity enhancement in response to a GBH-induced oxidant challenge. Moreover, cyanocobalamin supplementation abrogated GBH-induced oxidative stress as depicted by stabilized GSH levels in the liver, kidney, lungs, and brain. In the presence of cyanocobalamin, the GBH-induced liver injury depicted by elevation of AST, ALT, and bilirubin, was attenuated. From the results, we conclude that the capacity of cyanocobalamin to assuage GBH-induced inflammatory responses, hepatotoxicity, and hematological alteration as well as oxidative stress may be attributable to its antioxidant and anti-inflammatory properties. The current findings provide a solid foundation for further scrutiny of this phenomenon, with vital implications in GBH exposure and the role of potent antioxidant supplementation in the management of GBH-induced toxicity.

12 August 2022 in Laboratory Animal Research
Verified
Journal Article
Open access
PDF file
POPherah A. Ouma
Pherah A. Ouma
VMVictoria K. Mwaeni
Victoria K. Mwaeni
PAPeris W. Amwayi
Peris W. Amwayi
AIAlfred Orina Isaac
Alfred Orina Isaac
JNJames nyabuga Nyariki
James nyabuga Nyariki
Background: Calcium carbide (CaC2) is a chemical primarily used in the production of acetylene gas. The misuse of CaC2 to induce fruit ripening is a global challenge with a potential adverse effects to human health. Additionally, CaC2 is known to contain some reasonable amount of arsenic and phosphorous compounds that are toxic and pose a danger to human health when ingested. The current study sought to characterize CaC2 toxicity and elucidate any protective effects by cyanocobalamin (vitamin B12), a well-established antioxidant and anti-inflammatory bio-molecule. Female Swiss white mice were randomly assigned into three groups; the first group was the control, while the second group was administered with CaC2. The third group received CaC2 followed by administration of vitamin B12. The mice were sacrificed at 60 days post treatment, hematological, biochemical, glutathione assay, cytokine ELISA and standard histopathology was performed. Results: CaC2 administration did not significantly alter the mice body weight. CaC2 administration resulted in a significant decrease in packed cell volume (PCV), hemoglobin (Hb), red blood cells (RBCs) and RBC indices; indicative of CaC2-driven normochromic microcytic anaemia. Further analysis showed CaC2-driven leukopenia. Evidently, vitamin B12 blocked CaC2-driven suppression of PCV, Hb, RBCs and WBCs. Monocytes and neutrophils were significantly up-regulated by CaC2. CaC2-induced elevation of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and bilirubin signaled significant liver damage. Notably, vitamin B12 stabilized AST, ALT and bilirubin in the presence of CaC2, an indication of a protective effect. Histopathological analysis depicted that vitamin B12 ameliorated CaC2-driven liver and kidney injury. CaC2 resulted in the depletion of glutathione (GSH) levels in the liver; while in the brain, kidney and lungs, the GSH levels were elevated. CaC2 administration resulted in elevation of pro-inflammatory cytokines TNF-α and IFN-γ. Vitamin B12 assuaged the CaC2-induced elevation of these pro-inflammatory cytokines. Conclusions: These findings demonstrate for the first time that oral supplementation with vitamin B12 can protect mice against CaC2-mediated toxicity, inflammation and oxidative stress. The findings provide vital tools for forensic and diagnostic indicators for harmful CaC2 exposure; while providing useful insights into how vitamin B12 can be explored further as an adjunct therapy for CaC2 toxicity.

28 June 2023 in Parasitology International
Verified
Journal Article
Closed access
JOJames O. Oula
James O. Oula
JMJohn Mokua Mose
John Mokua Mose
NWNaomi N. Waiganjo
Naomi N. Waiganjo
KCKennedy W. Chepukosi
Kennedy W. Chepukosi
NMNancy S. Mitalo
Nancy S. Mitalo
JNJames nyabuga Nyariki
James nyabuga Nyariki

10 October 2023 in Journal of Toxicology
Verified
Journal Article
Open access
PDF file
NWNancy Wambui Wairimu
Nancy Wambui Wairimu
PWPeninah Wairagu
Peninah Wairagu
KCKennedy W. Chepukosi
Kennedy W. Chepukosi
GOGeorge F. Obiero
George F. Obiero
POPatrick W. Okanya
Patrick W. Okanya
JNJames nyabuga Nyariki
James nyabuga Nyariki
Sodium metabisulfite (SMB) is a biocide and antioxidant agent generally used as a preservative in food and beverage industries but can oxidize to harmful sulfite radicals. A standardized Ginkgo biloba (EGb-761) has demonstrated potent antioxidant and anti-inflammatory activities, which is beneficial for the treatment of diseases that exhibit oxidative stress and inflammation. The present study sought to investigate the putative ameliorative effects of EGb-761 against SMB-induced toxicity in mice. Thirty-two male Swiss white mice were randomized into control, SMB-treated, SMB+EGb-761-treated, and EGb-761-treated groups. EGb-761 (100mg/kg/day) and SMB (98mg/kg/day) were administered by gastric gavage for 40days. Oral administration of EGb-761 restored SMB-induced decrease in body weight and prevented SMB-induced thrombocytopenia, leukocytosis, and anemia. Furthermore, EGb-761-treatment protected against SMB-induced liver and kidney injury depicted by decreased serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, bilirubin, creatinine, urea, uric acid, and albumin. Furthermore, EGb-761 treatment attenuated SMB-driven dyslipidemia and metabolic acidosis. Besides, EGb-761 supplementation abrogated SMB-driven oxidative stress as depicted by stabilized reduced glutathione (GSH) levels in the brain, liver, kidney, spleen, heart, and lungs. SMB induced a significant increase of tissue levels of malondialdehyde (MDA), serum nitric oxide (NO), interferon-gamma (IFN-γ) and tumor necrosis factor-α (TNF-α) which were abrogated by EGb-761 treatment. In conclusion, these results deepen our understanding of EGb-761 in light of various detrimental effects of SMB-driven toxicities. These findings provide a novel approach that can be optimized for preventing or treating exposure due to SMB toxicity.

28 June 2023 in Molecular and Biochemical Parasitology
Verified
Journal Article
Closed access
JNJames nyabuga Nyariki
James nyabuga Nyariki
Njogu M. KimaniNjogu M. Kimani
Njogu M. Kimani
PKPeter Shikuku Kibet
Peter Shikuku Kibet
GKGeoffrey K. Kinuthia
Geoffrey K. Kinuthia
AIAlfred Orina Isaac
Alfred Orina Isaac

31 January 2022 in Journal of Parasitic Diseases
Verified
Journal Article
Closed access
PDF file
DODavid B. Ouko
David B. Ouko
PAPeris W. Amwayi
Peris W. Amwayi
LOLucy A. Ochola
Lucy A. Ochola
PWPeninah M. Wairagu
Peninah M. Wairagu
AIAlfred Orina Isaac
Alfred Orina Isaac
JNJames nyabuga Nyariki
James nyabuga Nyariki