Background:The antimicrobial resistance catastrophe is a growing global health threat and predicted to be worse in developing countries. Phages for Global Health (PGH) is training scientists in these regions to isolate relevant therapeutic phages for pathogenic bacteria within their locality, and thus contributing to making phage technology universally available.Materials and Methods:During the inaugural PGH workshop in East Africa, samples from Ugandan municipal sewage facilities were collected and two novel Escherichia coli lytic phages were isolated and characterized.Results:The phages, UP19 (capsid diameter ∼100 nm, contractile tail ∼120/20 nm) and UP30 (capsid diameter ∼70 nm, noncontractile tail of ∼170/20 nm), lysed ∼82% and ∼36% of the 11 clinical isolates examined, respectively. The genomes of UP19 (171.402 kb, 282 CDS) and UP30 (49.834 kb, 75 CDS) closely match the genera Dhakavirus and Tunavirus, respectively.Conclusion:The phages isolated have therapeutic potential for further development against E. coli infections.
Despite the recognised need for education and training in laboratory animal science (LAS) and ethics in Africa, access to such opportunities has historically been limited. To address this, the Pan-African Network for Laboratory Animal Science and Ethics (PAN-LASE) was established to pioneer a support network for the development of education and training in LAS and ethics across the African continent.In the 4.5 years since the establishment of PAN-LASE, 3635 individuals from 28 African countries have participated in our educational activities. Returning to their home institutions, they have both established and strengthened institutional and regional hubs of knowledge and competence across the continent. Additionally, PAN-LASE supported the development of guidelines for establishment of institutional Animal Ethics Committees, a critical step in the implementation of ethical review processes across the continent, and in enhancing animal welfare and scientific research standards.Key challenges and opportunities for PAN-LASE going forward include the formalisation of the network; the sustainability of education and training programmes; implementation of effective hub-and-spoke models of educational provision; strengthening governance frameworks at institutional, national and regional levels; and the availability of Africa-centric open access educational resources.Our activities are enhancing animal welfare and the quality of animal research undertaken across Africa, enabling African researchers to undertake world-leading research to offer solutions to the challenges facing the continent. The challenges, successes and the lessons learnt from PAN-LASE's journey are applicable to other low- and middle-income countries across the world seeking to enhance animal welfare, research ethics and ethical review in their own country or region.
Objectives: The use of bacteriophages (phages) as an alternative treatment for multidrug-resistant bacteria has recently gained popularity. Phage cocktails have been proposed for broad-spectrum therapeutic effects against such resistant bacteria. However, the effectiveness of non-locally formulated phage cocktails for therapy on Kenyan isolates has yet to be evaluated and is a subject of investigation. This study aimed to determine the in vitro effectiveness of a non-locally made commercial pyophage cocktail on clinical Pseudomonas aeruginosa isolates from Kenya. Methodology: Forty-nine P. aeruginosa isolates from Kenya were subjected to a pyophage cocktail for efficacy studies using direct spot test (DST) and efficiency of plating (EOP). Results: The success rate of the cocktail was observed on 16.3% (8/49) isolates only and ineffective on 83.7% (41/49) isolates. Six of the eight isolates that showed cross-reactivity from DST had complete lysis with a faintly hazy background. Five of these six isolates resulted in successful and high phage progeny production in plaquing efficiency (EOP ≥ 0.5). Conclusion: Non-locally made commercial pyophage cocktail was ineffective against the 83.7% endemic clinical strains of the Kenyan P. aeruginosa isolates, demonstrating the importance of locally derived phage cocktails against endemic and multidrug-resistant isolates. J Microbiol Infect Dis 2023; 12(4):25-30.
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.
This study sought to determine whether chronic exposure to khat (Catha Edulis, Forsk) increases the vulnerability to the toxic effects of manganese (Mn2+), when co-exposed. Three (3)-week-old forty (40) Swiss albino mice were randomly divided into four groups (n = 10). The various groups received khat and manganese separately or both. The experiment was conducted for 132 days to mimic chronic exposure to khat, with manganese administration in the last twelve days. Khat-induced neurological deficits were markedly pronounced on co-exposure with manganese. Notably, deficits in motor performance, touch escape and aggression were deepened by manganese. Co-exposure (khat + Mn2+) induced more profound changes in hematological indices such as suppression of RBCs, low hematocrit and hemoglobin levels. Manganese enhanced khat-induced depletion of a very powerful antioxidant, glutathione (GSH) in the brain, liver, heart and lung tissues. Exposure to khat and/or manganese led to significant elevations in the pro-inflammatory cytokines—tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-ϒ), with a concomitant suppression of the anti-inflammatory cytokine and interleukin 10 (IL-10). Similarly, there was enhanced suppression of IL-10 following co-exposure (khat + Mn). Khat-induced hepatotoxicity and nephrotoxicity were exacerbated by co-exposure. In conclusion, acute exposure to manganese appears to aggravate neurological deficits and other multiple organ toxicities driven by chronic exposure to khat.
Abstract Background Arsenic poisoning affects millions of people. The inorganic forms of arsenic are more toxic. Treatment for arsenic poisoning relies on chelation of extracellularly circulating arsenic molecules by 2,3-dimecaptosuccinic acid (DMSA). As a pharmacological intervention, DMSA is unable to chelate arsenic molecules from intracellular spaces. The consequence is continued toxicity and cell damage in the presence of DMSA. A two-pronged approach that removes extracellular arsenic, while protecting from the intracellular arsenic would provide a better pharmacotherapeutic outcome. In this study, Coenzyme Q10 (CoQ10), which has been shown to protect from intracellular organic arsenic, was administered separately or with DMSA; following oral exposure to sodium meta-arsenite (NaAsO2) – a very toxic trivalent form of inorganic arsenic. The aim was to determine if CoQ10 alone or when co-administered with DMSA would nullify arsenite-induced toxicity in mice. Methods Group one represented the control; the second group was treated with NaAsO2 (15 mg/kg) daily for 30 days, the third, fourth and fifth groups of mice were given NaAsO2 and treated with 200 mg/kg CoQ10 (30 days) and 50 mg/kg DMSA (5 days) either alone or in combination. Results Administration of CoQ10 and DMSA resulted in protection from arsenic-induced suppression of RBCs, haematocrit and hemoglobin levels. CoQ10 and DMSA protected from arsenic-induced alteration of WBCs, basophils, neutrophils, monocytes, eosinophils and platelets. Arsenite-induced dyslipidemia was nullified by administration of CoQ10 alone or in combination with DMSA. Arsenite induced a drastic depletion of the liver and brain GSH; that was significantly blocked by CoQ10 and DMSA alone or in combination. Exposure to arsenite resulted in significant elevation of liver and kidney damage markers. The histological analysis of respective organs confirmed arsenic-induced organ damage, which was ameliorated by CoQ10 alone or when co-administered with DMSA. When administered alone, DMSA did not prevent arsenic-driven tissue damage. Conclusions Findings from this study demonstrate that CoQ10 and DMSA separately or in a combination, significantly protect against arsenic-driven toxicity in mice. It is evident that with further pre-clinical and clinical studies, an adjunct therapy that incorporates CoQ10 alongside DMSA may find applications in nullifying arsenic-driven toxicity.
Background Cryptosporidiosis causes high morbidity and mortality in children under 2 years of age globally. The lack of an appropriate animal model that mimics the pathogenesis of disease in humans has hampered the development and testing of potential therapeutic options. This study aimed to develop and validate an infant baboon infection model of cryptosporidiosis. Methods Eighteen immunocompetent weaned infant baboons aged 12 to 16 months were used. The animals were n = 3 controls and three experimental groups of n = 5 animals each inoculated with Cryptosporidium parvum oocysts as follows: group 1: 2 × 10 4 , group 2: 2 × 10 5 , group 3: 2 × 10 6 followed by daily fecal sampling for oocyst evaluation. Blood sampling for immunological assay was done on the day of infection and weekly thereafter until the end of the experiment, followed by necropsy and histopathology. Statistical analysis was performed using R, SPSS, and GraphPad Prism software. Analysis of variance (ANOVA) and Bonferroni post hoc tests were used for comparison of the means, with p < 0.05 considered as a significant difference. Correlation coefficient and probit analysis were also performed. Results In all experimental animals but not controls, the onset of oocyst shedding occurred between days 2 and 4, with the highest oocyst shedding occurring between days 6 and 28. Histological analysis revealed parasite establishment only in infected animals. Levels of cytokines (TNF-α, IFN-γ, and IL-10) increased significantly in experimental groups compared to controls. Conclusion For developing a reproducible infant baboon model, 2 × 10 4 oocysts were an effective minimum quantifiable experimental infection dose. Graphic abstract
Ethnopharmacological relevance: The consumption of khat (Catha Edulis, Forsk) is on the rise despite the much publicized associated deleterious health effects. How chemicals present in khat, affect various physiological and biochemical processes requires further scrutiny. A clear understanding of these processes will provide an avenue for countering khat-driven negative effects using appropriate pharmacological and/or nutritional interventions. Aim of the study: The current study investigated the effect of khat on vital physiological and biochemical processes such as oxidative stress, inflammation and immune responses and the role of Coenzyme-Q10 (CoQ10), a potent antioxidant and anti-inflammatory, in modulating any negative effects due to khat exposure. Methodology: Three (3) weeks old forty (40) Swiss albino mice were randomly assigned into four treatment groups (n = 10). The first group was the control that was not administered with khat or CoQ10. The second group received 200 mg/kg body weight (b/w) of CoQ10, while the third group received 1500 mg/kg b/w of khat extract and finally the forth group was co-treated with 200 mg/kg b/w of CoQ10 and 1500 mg/kg b/w of khat extract. The experiment was conducted for 90 days after which samples were collected for physiological and biochemical analyses. Results: The effects of khat and CoQ10 on the weights of brain, liver, kidney and spleen was determined. Administration of khat decreased the levels of RBCs and its subtypes (MCV, MCH, RDW-SD and RDW-CV), a clear indicator of khat-induced normochromic microcytic anemia. White blood cells (lymphocytes, monocytes, neutrophils and eosinophil) which are vital in responding to infections were markedly elevated by khat. Moreover, these results provide evidence for khat-induced liver and kidney injury as shown by increased biomarkers; AST, ALT, GGT and creatinine respectively. Standard histopathological analysis confirmed this finding for khat-driven liver and kidney injury. Further studies showed evidence for khat-induced inflammation and oxidative stress as depicted by increased levels of the pro-inflammatory cytokine TNF-alpha and elevation of GSH in the brain, liver and spleen. Remarkably, this is the first study to demonstrate the potential of CoQ10 in ameliorating khat-induced negative effects as outlined. CoQ10 supplementation restored the khat-induced reduction in RBC subtypes, and was protective against liver and kidney injury as shown by the appropriate biomarkers and standard histopathology analysis. The other significant finding was the CoQ10-driven normalization of GSH and TNF-α levels, indicating a protective effect from khat-driven oxidative stress and inflammation respectively. Conclusion: From this study, we conclude that CoQ10 may be useful in nullifying khat-driven deleterious events among chronic khat users.
In animal model of experimental cerebral malaria (ECM), the genesis of neuropathology is associated with oxidative stress and inflammatory mediators. There is limited progress in the development of new approaches to the treatment of cerebral malaria. Here, we tested whether oral supplementation of Coenzyme Q10 (CoQ10) would offer protection against oxidative stress and brain associated inflammation following Plasmodium berghei ANKA (PbA) infection in C57BL/6 J mouse model. For this purpose, one group of C57BL/6 mice was used as control; second group of mice were orally supplemented with 200 mg/kg CoQ10 and then infected with PbA and the third group was PbA infected alone. Clinical, biochemical, immunoblot and immunological features of ECM was monitored. We observed that oral administration of CoQ10 for 1 month and after PbA infection was able to improve survival, significantly reduced oedema, TNF-α and MIP-1β gene expression in brain samples in PbA infected mice. The result also shows the ability of CoQ10 to reduce cholesterol and triglycerides lipids, levels of matrix metalloproteinases-9, angiopoietin-2 and angiopoietin-1 in the brain. In addition, CoQ10 was very effective in decreasing NF-κB phosphorylation. Furthermore, CoQ10 supplementation abrogated Malondialdehyde, and 8-OHDG and restored cellular glutathione. These results constitute the first demonstration that oral supplementation of CoQ10 can protect mice against PbA induced oxidative stress and neuro-inflammation usually observed in ECM. Thus, the need to study CoQ10 as a candidate of antioxidant and immunomodulatory molecule in ECM and testing it in clinical studies either alone or in combination with antimalaria regimens to provide insight into a potential translatable therapy.
Malaria is a life threatening infectious diseases transmitted by the bite of infected female Anopheles mosquito and responsible for high morbidity and mortality rates. Cerebral malaria is a complex neurological syndrome, whose pathology is mediated by inflammatory processes triggered by the immune system of the host following infection with Plasmodium falciparum. Coenzyme Q10 is an obligatory cofactor in the electron transport chain. The reduced form of Coenzyme Q10 serves as a potent antioxidant additionally; Coenzyme Q10 has been identified as a modulator of gene expression, inflammation and apoptosis. However, the modulatory effects of Coenzyme Q10 Plasmodium berghei ANKA infection process and risk occurrence of experimental cerebral malaria (ECM) have not been determined. The aim of this study was to elucidate the putative impact of oral administration of Coenzyme-Q10 on the initiation or regulation of inflammatory immune response in ECM of C57BL/6 mice during Plasmodium berghei ANKA (PbA) infection. We observed that oral administration of Coenzyme-Q10 both before and after PbA infection significantly hampered infiltration of inflammatory monocytes into the brain. Furthermore, pro-inflammatory cytokine TNF-α, which is associated with inflammation during ECM, was down-regulated in Coenzyme-Q10 administered mice. Remarkably, Coenzyme-Q10 was very effective in inhibiting dendritic cell differentiation. These data collectively demonstrated the immuno-modulatory function of Coenzyme-Q10 on host inflammatory responses during ECM. Keywords: Plasmodium berghei ANKA, Coenzyme Q10, experimental cerebral malaria DOI : 10.7176/JNSR/9-2-05
Human skin is morphologically and physiologically different from the skin of other primates. However, the genetic causes underlying human-specific skin characteristics remain unclear. Here, we quantitatively demonstrate that the epidermis and dermis of human skin are significantly thicker than those of three Old World monkey species. In addition, we indicate that the topography of the epidermal basement membrane zone shows a rete ridge in humans but is flat in the Old World monkey species examined. Subsequently, we comprehensively compared gene expression levels between human and nonhuman great ape skin using next-generation cDNA sequencing (RNA-Seq). We identified four structural protein genes associated with the epidermal basement membrane zone or elastic fibers in the dermis (COL18A1, LAMB2, CD151, and BGN) that were expressed significantly greater in humans than in nonhuman great apes, suggesting that these differences may be related to the rete ridge and rich elastic fibers present in human skin. The rete ridge may enhance the strength of adhesion between the epidermis and dermis in skin. This ridge, along with a thick epidermis and rich elastic fibers might contribute to the physical strength of human skin with a low amount of hair. To estimate transcriptional regulatory regions for COL18A1, LAMB2, CD151, and BGN, we examined conserved noncoding regions with histone modifications that can activate transcription in skin cells. Human-specific substitutions in these regions, especially those located in binding sites of transcription factors which function in skin, may alter the gene expression patterns and give rise to the human-specific adaptive skin characteristics.
Diurnal gene expression patterns underlie time-of-the-day-specific functional specialization of tissues. However, available circadian gene expression atlases of a few organs are largely from nocturnal vertebrates. We report the diurnal transcriptome of 64 tissues, including 22 brain regions, sampled every 2 hours over 24 hours, from the primate Papio anubis (baboon). Genomic transcription was highly rhythmic, with up to 81.7% of protein-coding genes showing daily rhythms in expression. In addition to tissue-specific gene expression, the rhythmic transcriptome imparts another layer of functional specialization. Most ubiquitously expressed genes that participate in essential cellular functions exhibit rhythmic expression in a tissue-specific manner. The peak phases of rhythmic gene expression clustered around dawn and dusk, with a "quiescent period" during early night. Our findings also unveil a different temporal organization of central and peripheral tissues between diurnal and nocturnal animals.
Skin wound healing of wild and laboratory animals including mice and rats have been classically known to be very rapid compared to that of human. However, there are few reports measuring the exact wound healing rates of over multiple mammalian species including human, primates, rodents and others. Three different primate species, baboons (Papio anubis), Sykes’ monkeys (Cercopithecus albogularis) and Vervet monkeys (Chlorocebus pygerythrus), were recruited as representatives of primates to this study in the collaboration with Institute of Primate Research in Kenya. For comparison, mice, hairless mice and pigs (Agubuta, endemic species of the Ryukyus) were also engaged. Full thickness skin defects of 3–4 cm in diameter were made on the back skin of these animals, and the sizes of the ulcers were measured periodically. To analyze the healing speed of human skin, we measured the skin defects of hospitalized adult patients who were resected of their skin cancer and waited for two-stage skin grafts. The three primates showed similar wound closure speeds; the average reduction in size of wounds was of 66.2 mm2 per day. Of the most interesting, the equivalent healing rates were obtained in wounds of multiple mice and pigs regardless of the presence of body hair. In contrast, the average healing rate of human skin defects was of 11.8 mm2 per day, more than five times slower than those of all examined primates and experimental animals. From our data, the human should be the evolutionary exceptional mutant animal in the aspect of wound healing even compared with the closely related primates. During the evolutional process to obtain the human specific skin phenotype, homo sapience must have lost some key gene or cellular function to contract the skin wounds.
Cerebral malaria is a complex neurological syndrome, whose pathology is mediated by inflammatory processes triggered by the immune system of the host following infection with P. falciparum. Coenzyme Q10 (CoQ10) is an obligatory cofactor in the electron transport chain and a potent antioxidant which has been identified as a modulator of gene expression, inflammation and apoptosis. However, the modulatory effects of CoQ10 during Plasmodium berghei ANKA (PbA) infection process and risk occurrence of experimental cerebral malaria (ECM) have not been Original Research Article Nyariki et al.; SAJP, 2(2): 1-9, 2019; Article no.SAJP.46442 2 determined. In the present study we sought to determine the role of CoQ10 in regulation of innate lymphoid cells during pathogenic immune responses of ECM. We observed significant increase in the percentage of Innate lymphoid class two (ILC2) in the spleens of Co-Q10 supplemented PbAinfected mice; whereas the frequency of Innate lymphoid class one (ILC1) and Innate lymphoid class three (ILC3) were comparable in the spleens upon PbA infection. The results also show Splenic ILC2 from CoQ10 mice are avid co-producer of IL-13 (Th2 phenotype cytokine) during ECM. Our data collectively demonstrates that Coenzyme Q10 administration was very effective in stimulating ILC2, which are known to play a protective role during ECM.