Sex-dependent vulnerability for Wistar rats model following intranasal instillation with Klebsiella pneumoniae ATCC 43816 causing lobar pneumonia.

BACKGROUND: Klebsiella pneumoniae has become one of the major threats to public health as it causes nosocomial and community-acquired infections like lobar pneumonia. This infection causes acute inflammation in the lung, characterized by the recruitment of polymorphonuclear cells, generating free radicals, and decreasing the endogenous antioxidant balance system. Many experimental studies have focused on the induction, progression and resolution of infection up to its peak, but these documented processes remain highly random and their sex dependence un-elicited. These fluctuations of physiopathological parameters would impact disease progression depending on the animal's model and bacterial strain used. The present study investigated the sex-dependent vulnerability of Wistar rats to K. pneumoniae ATCC 43816 lobar pneumonia induced by the intranasal instillation method. METHODS: Experimental pneumonia was induced by K. pneumoniae ATCC 43816 in male and female Wistar rats following intranasal instillation. The physiopathogenesis of the disease was studied by bacteriological and histopathological exams, histomorphometric analysis of the blood and/or lung tissue, and body weight loss in infected animals. In addition, the overall severity of lesions was determined by the total score obtained by averaging the individual scores from the same group of animals. RESULTS: The K. pneumoniae ATCC 43816 strain showed inoculation dose-, incubation time of the disease- and sex-dependent- differences in its ability to induce lobar pneumonia. Evaluation of different parameters showed that the disease peaked on day 15 post-inoculation, with more pathogenic effects on female rats. This observed sex-dependence difference in Wistar rats was mainly highlighted by the determined lethal dose 50 (LD50), bacterial load count in whole blood and lung tissues, body weight loss, inflammatory granulomas forming and diffuse alveolar damages. The pathogenicity was confirmed by scoring the severity of pathologic lesions of lung tissues. CONCLUSIONS: The results obtained highlighted the gender-dependency in the physiopathogenesis processes of K. pneumoniae ATCC 43816 induced-lobar pneumonia, in Wistar rats. Female Wistar rats' susceptibility is useful in studying pathology and in preclinical trial investigations of new treatments for infectious pneumonia.

The Aqueous Extract of Sclerocarya birrea, Nauclea latifolia, and Piper longum Mixture Protects Striatal Neurons and Movement-Associated Functionalities in a Rat Model of Diabetes-Induced Locomotion Dysfunction.

Among the many complications of type 2 diabetes (T2D), locomotor disorders have been poorly studied and understood. Therefore, no disease-modifying treatment is usually considered. The study aimed to investigate the effect of the aqueous extract of Sclerocarya birrea, Nauclea latifolia, and Piper longum (SNP) mixture on locomotor activity in fructose/streptozotocin-induced diabetic rats. T2D was induced by 10% fructose orally (6 weeks) and streptozotocin (STZ, 35 mg/kg, i.v.) in 25 male rats. Diabetic animals received distilled water, metformin (200 mg/kg), or the aqueous extract of the SNP mixture (75, 150, or 300 mg/kg). A 10-minute open field test was performed in diabetic rats (glycemia: 126 and 350 mg/dL) to assess locomotor activity before and after treatment. A group of 5 normal rats (NC) served as controls throughout the study. Rats were sacrificed, and the striatum was removed for biochemical and histological studies. In untreated diabetic rats, fructose/STZ administration resulted in hyperglycemia that altered locomotor function as characterized by increased freezing time, decreased mobility time, number of lines crossed, and total travel time compared to NC. MDA, TNF-α, INF-γ, and nitrite levels were elevated in the striatum of diabetic rats, while catalase activity and GSH levels were decreased, indicating oxidative stress and neuroinflammatory changes. In untreated diabetic rats, the microstructure of the HE-stained striatum revealed lipid vacuolation (hydropic degeneration) of the parenchyma, indicating a loss of neuronal integrity. The locomotor dysfunction was significantly improved by the aqueous extract of the SNP mixture, both biochemically and histologically. As a result, our findings support the mixture's ability to correct diabetes-related locomotion disorders as a glucose-lowering product and antioxidant, anti-inflammatory, and neuroprotective agent. These results justify the use of the aqueous extract of a combination of these three plants to manage diabetes and neuroinflammatory complications in Northern Cameroon.

Chromolaena odorata (L.) R. M. King and H. Robinson Leaves Aqueous Extract Improves the Femoral Head in Ethanol-Induced Osteonecrosis in Rats.

Chronic alcohol consumption damages bone formation and causes bone pathology, including osteonecrosis of the femoral head. The aim of this work was to evaluate the effects of the leaf aqueous extract of Chromolaena odorata (C. odorata) on the femoral head in ethanol-induced osteonecrosis in rats. Animals received alcohol (40°) at 3 g/kg for 12 weeks. A group of animals were sacrificed to attest to the instalment of osteonecrosis by using histopathological analysis. The remaining animals received alcohol concomitantly with the plant extract (150, 300, or 600 mg/kg) or diclofenac (1 mg/kg) for 28 additional days. At the end of the experimental period, biochemical parameters including total cholesterol, triglycerides, calcium, alkaline phosphatase (ALP), reduced glutathione (GSH), malondialdehyde (MDA), nitrite, superoxide dismutase (SOD), and catalase activities were measured. Histopathological and histomorphometry analyses of femurs were also assessed. The administration of alcohol, irrespective of the experimental period, induced a significant increase in total cholesterol (p < 0.05) and triglyceride (p < 0.01) and a decrease in ALP (p < 0.05) and calcium (p < 0.05-p < 0.001) levels. Intoxicated animals showed an alteration in oxidative stress parameters accompanied by a significant drop in bone cortical thickness and density with necrosis and marked bone resorption. The concomitant administration of the plant with ethanol reversed the alcohol-induced bone defect, characterized by the improvement of the lipid profile (p < 0.001), bone calcium concentration (p < 0.05), bone ALP activity (p < 0.001), oxidative stress parameters, improved cortical bone thickness (p < 0.01), and bone density (p < 0.05). These results are supported by the absence of bone resorption with an obvious effect at a dose of 300 mg/kg. The pharmacological effect of the extract on ethanol-induced osteonecrosis of the femoral head is probably due to its osteogenic, hypolipidemic, and antioxidant properties, justifying its use in Cameroonian folk medicine for articulation and bone pain management.

Curative anti-typhoid effect of Detarium microcarpum Guill. & Perr. (Leguminosae) hydroethanolic extract root bark based-on in vivo and molecular docking analyses.

ETHNOPHARMACOLOGICAL RELEVANCE: Detarium microcarpum is used to treat typhoid fever, a major public health problem, by indigenous population in Africa. Though its preventive activities have been documented, the curative effect is still to be confirmed. AIM OF THE STUDY: This study aimed at evaluating the curative effects of the hydroethanolic extract of Detarium microcarpum root bark on Salmonella typhimurium-induced typhoid in rat and exploring the in-silico inhibition of some bacterial key enzymes. STUDY DESIGN: In vitro antioxydant, in vivo antisalmonella of the extract and in silico molecular docking assay on the isolated compounds were carried out to explore the anti-salmonella effects of Detarium microcarpum. MATERIAL AND METHODS: The in vitro antioxidant properties of the extract were evaluated using DPPH, ABTS and FRAP tests. The anti-salmonella activity of the extract was assessed through feacal sample from Salmonella typhimurium-infected rat cultured in Salmonella-Shigella agar (SS agar) medium. The affinity of isolated compounds (Rhinocerotinoic acid and Microcarposide) from the extract were performed on four key enzymes (Adenylosuccinate lyase, Acetyl coenzyme A synthetase, Thymidine phosphorylase and LuxS-Quorum sensor) using molecular docking simulation to elucidate the molecular level inhibition mechanism. RESULTS: Crude extract of D. microcarpum root bark showed variable activities on DPPH (RSa50: 6.09 ± 1.04 µg/mL), ABTS (RSa50: 24.46 ± 0.27), and FRAP (RSa50: 23.30 ± 0.23). The extract at all the doses exhibited significant healing effect of infected rats, with the complete clearance. The extract restored hematological, biochemical and histological parameters closed to the normal control. The molecular docking results indicates that rhinocerotinoic acid and microcarposide present more affinity to the LuxS-Quorum sensor and Acetyl coenzyme A synthetase protein as compared to the others. CONCLUSION: These results demonstrate potent anti-typhoid activities of the hydroethanolic of Detarium microcarpum root bark extract through antioxidant properties and high inhibitory affinity of its compounds on some bacterial key enzymes that justify its use as traditional medicine to typhoid fever.

Hydro-ethanolic extract of Khaya grandifoliola attenuates heavy metals-induced hepato-renal injury in rats by reducing oxidative stress and metals-bioaccumulation.

People living in developing countries are exposed to hepato-renal injuries induced by heavy metals like lead (Pb), cadmium (Cd), and mercury (Hg) since drinking water supplied is often polluted with a high concentration of those metals. Accordingly, it is necessary to search for antidotes against heavy metals poisoning. Hence, medicinal plants bearing anti-hepatotoxic properties represent a credible option; and such plant is Khaya grandifoliola. However, there is a paucity of knowledge regarding its protective effect on heavy metals-induced hepato-renal toxicity. Thus, this study was designed to assess the protective effect of the hydro-ethanolic stem bark extract of K. grandifoliola (HKG) against hepato-renal injuries induced by chronic consumption of drinking water containing high contents of Pb, Cd, and Hg; in addition to the investigation of the chemical antioxidant properties of HKG. For the antioxidant assays, HKG was tested as a potential inhibitor of lipid peroxidation, reducer of ferric and phosphomolybdenum, and scavenger of hydroxyl and 2,2-Diphenyl-Picryl-Hydrazyl radicals. Its protective effects were evaluated by daily co-treating rats with heavy metals solution (10 mL/kg b.w) containing 0.9, 0.58, and 1.13 ppm respectively for Pb, Cd and Hg and HKG (25 or 100 mg/kg b.w) for five consecutive months; and biochemical parameters associated to liver and kidneys functions, oxidative stress and metals bioaccumulation were assessed. HKG displayed a strong antioxidant capacity (IC50/EC50 range 3.95-17.17 µg/mL) correlated to its polyphenols content and comparable to that of Ascorbic acid. Serum levels of alkaline phosphatase, alanine/aspartate aminotransferase, and creatinine; renal and hepatic content of Cd and Pb, malondialdehyde and glutathione, activities of superoxide dismutase and catalase showed the protective effect of HKG, further evidenced by histopathological analysis. Taking together, these results demonstrated that HKG alleviates heavy metals-induced hepato-renal injuries in rats by reducing oxidative stress and metals-bioaccumulation.

Acute and Subchronic Toxicity Studies on the Aqueous Extract of the Plant Mixture (Bidens pilosa and Cymbopogon citratus Aerial Parts) in Rat Model.

Bidens pilosa (B. pilosa) and Cymbopogon citratus (C. citratus) are plants used individually or in combination in the traditional treatment of several ailments such as cardiovascular disorders. In order to valorise their traditional use, a toxicological study was conducted on the aqueous extract of the mixture of aerial parts of B. pilosa and C. citratus. The acute and subchronic toxicity studies were conducted according to the OECD 425 and 407 guidelines. Regarding the acute study, the aqueous extract of the mixture of B. pilosa and C. citratus 50 : 50 (2000 and 5000 mg/kg) was administered once to rats of both sexes. In the subchronic study, the aqueous extract of the mixture of B. pilosa and C. citratus (200, 400 and 800 mg/kg) was administered once daily to rats for 28 days. The aqueous extract of the mixture of B. pilosa and C. citratus (2000 and 5000 mg/kg) did not cause death and did not induce any apparent sign of toxicity during the 14 days of observation. The DL50 of the extract is therefore greater than 5000 mg/kg. Taken daily for 28 days, the extract had no significant effect on selected parameters (creatinine, AST, ALT, urea, and uric acid) of renal and hepatic function, as well as on the number of some blood cells. However, the aqueous extract of the mixture of B. pilosa and C. citratus (200 and 400 mg/kg) caused a significant (p < 0.05; p < 0.001, respectively) decrease in creatinine levels in male rats as compared to normal control animals. In females, the aqueous extract of the mixture of B. pilosa and C. citratus (200 and 400 mg/kg) resulted in a significant (p < 0.05) increase in total cholesterol levels as compared to normal control animals. The study showed that the aqueous extract of the mixture of B. pilosa and C. citratus has a low toxicity and does not cause any injury to the liver, kidney, lungs, or spleen.

Estrogenic and Antioxidant Activities of Pterocarpus soyauxii (Fabaceae) Heartwood Aqueous Extract in Bilateral Oophorectomized Wistar Rat.

Phytoestrogens are used to ease postmenopausal symptoms, a property probably due to estrogenic and antioxidant effects. Pterocarpus soyauxii (P. soyauxii) is empirically used in Cameroon to treat among others primary and secondary amenorrhea. The aim of this study is to evaluate estrogenic and antioxidant activities of P. soyauxii heartwood aqueous extract in bilateral oophorectomized Wistar rats. Firstly, a characterization of the extract was carried out. For that, flavonoids, phenols, and tannins levels in P. soyauxii extract were evaluated by colorimetric assays and UHPLC-MS analysis was realized. In vitro antioxidant analysis of P. soyauxii was conducted using DPPH, ABTS, and FRAP assays. Secondly, 2 sets of pharmacologic tests were carried out. The results revealed that P. soyauxii aqueous extract contains, respectively, 229.42 ± 3.62 mg EAG/g, 63.42 ± 2.16 mg EQ/g, and 27.88 ± 0.23 mg ETA/g of polyphenols, flavonoids, and tannins. UHPLC-MS enabled identifying seven components including mono(2-ethylhexyl) phthalate, cembrene, 3',5'-dimethoxy-4-stilbenol, and linoleic acid. DPPH, ABTS, and FRAP assays revealed that P. soyauxii extract possessed a high antioxidant activity with IC50 value of 730.20 µg/mL, 892.90 µg/mL, and 765.75 mEAG/g of extract, respectively. In the uterotrophic assay, P. soyauxii extract induced significant increase of fresh uterine weight, uterine and vaginal epithelial size, and mammary glands differentiation compared to Ovx control. In the postmenopausal model, compared to the sham control, vagina and uterine dystrophies were observed in Ovx rats treated with distilled water. P. soyauxii aqueous extract expressed estrogenic-like effects on vagina and did not affect uterine epithelial height compared with vehicle groups. On the back of these vaginotrophic effects, the extract displayed antiatherogenic properties by reducing (p < 0.001) AI and LDL cholesterol level as compared to Ovx control group. The extract at 200 mg/kg significantly prevented the increase of MDA (p < 0.01) level and decreased nitrites (p < 0.001) and GSH (p < 0.01) levels compared to Ovx rats. These beneficial effects are related at least in part to the presence of compound such as mono(2-ethylhexyl) phthalate, 3',5'-dimethoxy-4-stilbenol, and linoleic acid. Overall, P. soyauxii aqueous extract exhibits estrogenic and antioxidant effects which can inhibit postmenopausal symptoms by providing vaginal stratification, improving lipid profile and insulin sensitivity, and reducing oxidative stress without side effects on the endometrium and mammary gland in 84-day Ovx rats.

Inhibition of CYP2E1 and activation of Nrf2 signaling pathways by a fraction from Entada africana alleviate carbon tetrachloride-induced hepatotoxicity.

Entada africana is used in non-conventional medicine for the management of liver ailments. A fraction, designated EaF10 (methylene chloride/methanol 90:10, v/v) with promising hepatoprotective activity has been isolated. Since the mechanisms underlying EaF10 hepatoprotective action remain unknown, this study was undertaken to investigate the anti-hepatotoxic mechanism of the fraction against carbon tetrachloride (CCl4)-induced hepatotoxicity and its antioxidant properties. Antioxidant activities of EaF10 were assessed through four chemical antioxidant assays and its anti-hepatotoxic effect evaluated in vivo and in vitro by post-treatment (25 or 100 mg/Kg) or co-treatment (6.25-100 µg/mL) in CCl4-intoxicated mice and normal human liver cells line L-02 hepatocytes respectively; and biochemical and molecular parameters assessed respectively by spectrophotometry, and by quantitative real-time polymerase chain reaction and western blot analysis. EaF10 exhibited strong antioxidant activities correlated with its polyphenol content. Serum levels of alanine/aspartate aminotransferase (AST/ALT) and nitrite oxide, liver contents of glutathione (GSH) protein carbonylation and malondialdehyde (MDA), liver activities of catalase (CAT), glutathione-S-transferase (GST) and superoxide dismutase (SOD) and cell viability showed the anti-hepatotoxic effect of EaF10, supported by histopathological observations. The fraction decreased the protein level of Cytochrome P450 2E1 (CYP2E1) and Kelch-like ECH-associated protein-1 (Keap-1), induced nuclear translocation of Nuclear factor-erythroid 2-related factor-2 (Nrf2) coupled to an increase of the mRNA levels of CAT, SOD1 and GST in CCl4-intoxicated L-02 hepatocytes. These findings evidenced that the studied plant fraction possesses a strong antioxidant capacity and prevents CCl4-induced hepatotoxicity, likely through inhibition of CYP2E1 and activation of the Nrf2 signaling pathway.

Hydroethanolic Extract from Bridelia atroviridis Müll. Arg. Bark Improves Haematological and Biochemical Parameters in Nicotinamide-/Streptozotocin-Induced Diabetic Rats.

Bridelia atroviridis Müll. Arg. (B. atroviridis) is a plant used in Cameroonian traditional medicine to manage diabetes. The effects of hydroethanolic barks extract from B. atroviridis were evaluated on diabetes disorders including hematology, inflammatory, and oxidative stress parameters. The in vitro antioxidant capacity of the hydroethanolic bark extract (70 : 30) was evaluated. Nicotinamide-/streptozotocin-induced diabetic rats were daily treated with the B. atroviridis extract for fifteen days. Glycemia were evaluated every 5 days, insulin sensibility test was performed, and haematological, inflammatory, and oxidative stress parameters were analysed. Histomorphometry of the pancreas was realized. The extract was able to scavenge free radicals in vitro and decrease significantly the blood glucose levels. The treatment resulted in a significant alleviation of insulin resistance, anemia, leukocytopenia, and thrombocytopenia observed in untreated diabetic rats. The extract significantly decreased proinflammatory cytokines TNF-α, IL-1ß, and IL-10. The rate of reduced glutathione was increased in the pancreas, whereas the catalase activity and nitrite concentration were decreased. Diabetic control showed a reduced size of Langerhans islet, whereas the size of islets was large in treated groups. The hydroethanolic extract of B. atroviridis was able to improve glycemia and alleviate haematological and inflammatory parameters disorders observed in diabetic conditions, probably due to its antidiabetic, anti-inflammatory, and antioxidant capacities.