Arrested Acetylene-Induced Pulmonary and Testicular Toxicity in Rats Through Treatment With Polyphenols.

Occupational exposure to potentially harmful substances is one of the dangers associated with industrial jobs. This study evaluated the modulatory influence of selected dietary polyphenols on the pulmonotoxic and testiculotoxic effects of crude acetylene, an industrial gas used in welding metals. Wistar rats were exposed to 58 000 ppm acetylene, 20 min daily for 30 days, in a 36 L glass inhalation chamber. Some acetylene-exposed animals were treated concurrently with 30 mg/kg quercetin, rutin, caffeic acid, ferulic acid, or coumaric acid. At the end of the treatment sessions, the levels of superoxide dismutase, reduced glutathione, glutathione peroxidase, lactate dehydrogenase, and hormonal markers in rats exposed to acetylene were significantly decreased, with a concomitant increase in lipid peroxidation, nitric oxide level, cholesterol concentration, and histopathological abnormalities. These damaging biochemical and histopathological changes were significantly ameliorated in animals administered the polyphenols. Quercetin showed greater ameliorative activity than rutin while the phenolic acids exhibited increasing levels of ameliorative activity in the order: caffeic acid > ferulic acid > coumaric acid. These results indicate that inhalation of crude acetylene is deleterious to the lungs and testes, and polyphenols provide protection against these detrimental effects.

Dihydroquercetin improves rotenone-induced Parkinsonism by regulating NF-κB-mediated inflammation pathway in rats.

This study examined the effect of dihydroquercetin (DHQ), also knofigurewn as taxifolin, on rotenone-induced Parkinsonism in rats. Male Wistar rats were administered 1.5 mg/kg rotenone for 10 days and subsequently treated with 0.25-1.0 mg/kg DHQ for 3 days followed by the assessment of parkinsonian symptoms. Brain striatal redox stress and neurochemical dysfunction markers were assessed spectrophotometrically. Histopathological evaluation of the striatum was done by hematoxylin and eosin staining technique. The expression of genes involved in the activation of NF-κB signaling pathway (IL-1ß, TNF-α, NF-κB and IκKB), and the p53 gene in the striatum were determined by RT-qPCR. DHQ attenuated parkinsonian symptoms as well as striatal redox stress, neurochemical dysfunction, and histological alterations occasioned by rotenone toxicity. Importantly, DHQ significantly suppressed the rotenone-induced upregulation of IL-1ß, NF-κB, and IκKB expression (p < 0.05) in the striatum of parkinsonian rats. DHQ demonstrated notable neurotherapeutic potential against rotenone-induced Parkinsonism in rats by improving parkinsonian symptoms (bradykinesia, catalepsy, postural instability, impaired locomotor behavior, and tremor) and neurochemical dysfunctions via modulation of genes involved in the activation of the canonical pathway of NF-κB-mediated inflammation.

Modulatory activities of polyphenols on crude acetylene-induced cardiac and hepatic dysfunctions in a rat model.

Exposure to crude acetylene can occur in occupational settings. This study assessed the modulatory activities of selected polyphenols on the hematotoxic, cardiotoxic, and hepatotoxic effects of crude acetylene. Wistar rats were exposed to 58 000 ppm crude acetylene for 10 min at 12 h intervals for 30 days. Some exposed groups were treated with 50 mg/kg rutin, quercetin, gallic acid, or tannic acid. Indices of hematological disorder, oxidative stress, and cardiovascular and hepatocellular injuries were evaluated in animals. The results showed a decrease in the levels of hematological indices in crude acetylene-exposed animals except for white blood cell count which was increased. Decreased activity/level of reduced glutathione, superoxide dismutase and ferric reducing antioxidant power with increased lipid peroxidation was observed in animals exposed to crude acetylene. Activities of transaminases, γ-glutamyl transpeptidase, and level of bilirubin were increased while the plasma albumin level was decreased. Dyslipidemia, increased activities of lactate dehydrogenase and creatine kinase-MB, and severe histopathological damage to hepatic and cardiac tissues were also observed in animals exposed to the gas. These deleterious hematological, biochemical, and histopathological changes were ameliorated in crude acetylene-toxified rats treated with the polyphenols. Tannic acid exhibited better activity than gallic acid while quercetin showed a superior activity to rutin. The results indicate that exposure to crude acetylene can lead to blood, heart, and liver-related diseases and dietary polyphenols could provide protective benefits.

Prophylaxis with a multicomponent nutraceutical abates transient cerebral ischemia/reperfusion injury.

The effect of a multicomponent nutraceutical on cerebral ischemia/reperfusion injury in male Wistar rats was investigated. Animals were administered with the nutraceutical, Trévo™, for 7 days before 30 min of bilateral common carotid artery occlusion-induced cerebral ischemia and 24 hr of reperfusion. Behavioral assessment, biochemical estimations in the brain cortex, striatum, and hippocampus, and hippocampal histopathological evaluation were carried out after treatments. Results showed that ischemia/reperfusion-induced motor and cognitive deficits were abated in rats pretreated with Trévo™. Additionally, prophylaxis with Trévo™ blunted ischemia/reperfusion-induced redox stress, proinflammatory events, disturbances in neurotransmitter metabolism, mitochondrial dysfunction, and histoarchitectural aberrations in the discreet brain regions. In summary, supplementation with Trévo™ provided neuroprotection to rats against transient cerebral ischemia/reperfusion injury and could be explored as a promising approach in stroke prevention. PRACTICAL APPLICATIONS: There is a worldwide increase in the incidence of cerebral ischemia or stroke. Although an advanced health care system and effective control of risk factors have led to the declining incidence in developed nations, a definitive cure for stroke remains elusive and the situation is growing worse in developing nations. The results of the present study revealed that supplementation with Trévo™ ameliorated neurobehavioral, neurochemical, and histopathological consequences of brain ischemia/reperfusion injury and could, therefore, be beneficial in stroke prevention and management.

Modulation of key enzymes linked to Parkinsonism and neurologic disorders by Antiaris africana in rotenone-toxified rats.

Background The physiopathologies of many neurologic diseases are characterized by related biochemical dysfunctions that could be explored as drug targets. This study evaluated the effect of a methanol leaf extract of Antiaris africana (MEA) on critical bioindices of Parkinsonism and related neurologic dysfunctions in rats with rotenone-induced neurotoxicity. Methods Animals were administered 50 or 100 mg/kg MEA for 14 consecutive days. Rotenone (1.5 mg/kg) was administered three times per day on days 13 and 14. Coenzyme Q10 (5 mg/kg) was the reference drug. Complex I activity, dopamine level, activities of acetylcholinesterase, myeloperoxidase, Na+/K+ ATPase and glutamine synthetase, as well as oxidative stress indices were evaluated at the end of the period of treatment. Results Rotenone-intoxicated group showed disruption of complex 1 activity, dopamine level, and glutamine synthetase activity with negative alterations to activities of acetylcholinesterase, myeloperoxidase, and Na+/K+ ATPase as well as heightened cerebral oxidative stress. MEA restored brain mitochondria functionality, mitigated altered neurochemical integrity, and ameliorated cerebral oxidative stress occasioned by rotenone neurotoxicity. The activity of A. Africana was comparable with that of 5 mg/kg coenzyme Q10. Conclusions These results indicated that A. africana displayed therapeutic potential against Parkinsonism and related neurologic dysfunctions and support its ethnobotanical use for the treatment of neurologic disorders.

Dietary supplementation of tiger nut alters biochemical parameters relevant to erectile function in l-NAME treated rats.

Tiger nut tubers have been reportedly used for the treatment of erectile dysfunction (ED) in folk medicine without scientific basis. Hence, this study evaluated the effect of tiger nut on erectile dysfunction by assessing biochemical parameters relevant to ED in male rats by nitric oxide synthase (NOS) inhibitor, Nω-nitro-l-arginine methyl ester hydrochloride (l-NAME) treatment. Rats were divided into five groups (n = 10) each: Control group; l-NAME plus basal diet; l-NAME plus Sildenafil citrate; diet supplemented processed tiger nut (20%) plus l-NAME;diet supplemented raw tiger nut (20%) plus l-NAME. l-NAME pre-treatment (40 mg/kg/day) lasted for 14 days. Arginase, acetycholinesterase (AChE) and adenosine deaminase (ADA) activities as well as nitric oxide levels (NO) in serum, brain and penile tissue were measured. l-NAME increased the activity of arginase, AChE and ADA and reduced NO levels. However, dietary supplementation with tiger nut caused a reduction on the activities of the above enzymes and up regulated nitric oxide levels when compared to the control group. The effect of tiger nut supplemented diet may be said to prevent alterations of the activities of the enzymes relevant in erectile function. Quercetin was revealed to be the most active component of tiger nut tuber by HPLC finger printing.

Sausage tree (Kigelia africana) flavonoid extract is neuroprotective in AlCl3-induced experimental Alzheimer's disease.

Alzheimer's disease (AD) is a developmental neurodegenerative disorder for which there is no effective treatment or cure at present. In this study, the neuroprotective properties of a methanol extract of the leaves of Kigelia africana (KAE) and its flavonoid-rich fraction (FKAE) in aluminum chloride (AlCl3)-induced experimental AD was evaluated. Symptoms mimicking AD were induced in male Sprague Dawley rats by administering 17mg/kg AlCl3, orally, for six consecutive weeks. Pretreatment of animals with 50 and 100mg/kg KAE or FKAE for two weeks, followed by their co-administration with AlCl3 for a further four weeks ameliorated neurological deficits, cerebral oxidative stress, neurochemical disturbances and histoarchitectural alterations caused by AlCl3 intoxication. The results suggest that KAE and FKAE are promising therapeutic agents for AD.

MODULATION OF KEY BIOCHEMICAL MARKERS RELEVANT TO STROKE BY ANTIARIS AFRICANA LEAF EXTRACT FOLLOWING CEREBRAL ISCHEMIA/REPERFUSION INJURY.

BACKGROUND: Oxidative stress plays a significant role in stroke pathogenesis. Hence, plants rich in antioxidant phytochemicals have been suggested as effective remedies for prevention and treatment of stroke and other neurological diseases. Antiaris africana Engl. (Moraceae) is traditionally used for the management of brain-related problems but there is paucity of data on its anti-stroke potential. MATERIALS AND METHODS: Ischemia/reperfusion injury was induced by a 30 min bilateral common carotid artery occlusion/ 2 h reperfusion (BCCAO/R) in the brain of male Wistar rats. A sham-operated group which was not subjected to BCCAO/R and a group subjected to BCCAO/R without treatment with MEA served as controls. The ameliorative effect of 14 days of pretreatment with 50 mg/kg or 100 mg/kg A. africana methanol leaf extract (MEA) on BCCAO/R-mediated alterations to key markers of oxidative stress (malondialdehyde, reduced glutathione, xanthine oxidase, superoxide dismutase, catalase and glutathione peroxidase) and neurochemical disturbances and excitotoxicity (myeloperoxidase, glutamine synthetase, Na+/K+ ATPase, acetylcholinesterase and tyrosine hydroxylase), was evaluated and compared with the effect produced by treatment with 20 mg/kg quercetin as a reference standard. RESULTS: Results show that pretreatment with MEA significantly mitigated or reversed BCCAO/R-induced changes in the level or activity of the evaluated biochemical markers of oxidative stress, neurochemical dysfunction and excitotoxicity compared with the BCCAO/R untreated control group (p < 0.05). The effect produced by 100 mg/kg MEA was similar to that of the reference standard, quercetin. CONCLUSION: These results revealed the neuroprotective potential of A. africana in stroke and other ischemia-related pathologies.

Antidiabetic effects of Mangifera indica Kernel Flour-supplemented diet in streptozotocin-induced type 2 diabetes in rats.

Our previous report showed that Mangifera indica kernel flour (MIKF) is a rich source of pharmacologically important flavonoids and phenolic acids; and that its methanolic extract inhibits some key enzymes linked to the pathology and complications of type 2 diabetes (T2D) in vitro. Hence, this study evaluated the antidiabetic effects of 10% and 20% MIKF-supplemented diets in T2D in rats. T2D was induced in rats using a high-fat diet (HFD), low-dose streptozotocin (HFD/STZ) model, by feeding the rats with HFD for 2 weeks followed by single dose administration of STZ (40 mg/kg body weight, intraperitoneally). The diabetic rats were later fed the MIKF-supplemented diets, or administered with metformin (25 mg/kg b.w.) for 21 days; the control rats were fed basal diet during this period. Intake of the MIKF-supplemented diets resulted in significant (P < 0.05) improvement in the fasting blood glucose, hepatic glycogen, glycosylated hemoglobin, lipid profile, plasma electrolytes, hepatic and pancreatic malonaldehyde, and the liver function markers of the diabetic rats, compared with the diabetic control rats. The ameliorative effect of 20% MIKF-supplemented was comparable (P > 0.05) with that of metformin administration in the diabetic rats. It is concluded that M. indica kernel flour has antidiabetic effects in T2D rats, and could therefore be a promising nutraceutical therapy for the management of T2D and its associated complications.

Contribution of Musa paradisiaca in the inhibition of α-amylase, α-glucosidase and Angiotensin-I converting enzyme in streptozotocin induced rats.

AIMS: Unripe plantain based-diets are part of folklore remedy for the management of diabetes in tropical Africa; however, with the dearth of information on the rationale behind this practice; this study therefore, sought to investigate the antihyperglycemic effect of traditional unripe plantain products (Amala and Booli) in high fat fed/low dose streptozotocin-induced diabetic rats and to provide a possible rationale for their antidiabetic properties. MAIN METHODS: Diabetes was induced experimentally by high fat fed/low dose streptozotocin-diabetic rats (25mg/kg body wt.) and the diabetic rats were fed diets supplemented with 20-40% Amala and Booli for 14 days. The effect of the diets on the blood glucose level, pancreatic α-amylase, intestinal α-glucosidase and Angiotensin-I converting enzyme (ACE) activities and plasma antioxidant status as well as amylose/amylopectin content of the unripe plantain products were determined. KEY FINDINGS: A marked increase in the blood glucose, α-amylase, α-glucosidase and ACE activities with a corresponding decrease in plasma antioxidant status was recorded in diabetic rats. However, these indices were significantly (P < 0.05) reversed after unripe plantain product supplemented diet treatments for 14 days. Also, the amylose/amylopectin ratio of the products is 1:3. SIGNIFICANCE: This study revealed that unripe plantain products exert antihyperglycemic effects which could be attributed to the inhibition of α-amylase and α-glucosidase activities by their constituent phytochemicals as well as their amylose/amylopectin contents in the diabetic rats, hence, providing the possible rationale behind their antidiabetic properties.

Tetracarpidium conophorum (Mull.Arg) Hutch & Dalziel inhibits FeSO4-induced lipid peroxidation in rat's genitals.

BACKGROUND: To search for new sources of safe and inexpensive antioxidant agents which can be used to treat various oxidative stress-related diseases, the phenolic contents of leaf of Tetracarpidium conophorum were characterized and its effect on pro-oxidant induced oxidative stress in rat's genitals for the first time was investigated. METHODS: The aqueous extract of the plant was prepared, the antioxidant activities of the extract were then evaluated using spectrophotometric method. RESULTS: The result revealed that the introduction of aqueous extract of the plant caused significant concentration-dependent decrease (P < 0.05) in the MDA content of the Fe(2+)-stressed testes and penis homogenates. The least MDA production occurred at the highest concentration of the extract (0.625 mg/mL). However, characterization of the extract with HPLC revealed that its major constituents were gallic acid, catechin, chlorogenic acid, caffeic acid, coumarin, rutin, quercitrin, quercetin, kaempferol and luteolin. Also, the result revealed that the ABTS* scavenging ability of the extract was 4.60 mmol/100 g while its vitamin C content was 23.49 mg/g which indicated that the plant is very rich in vitamin C. Furthermore, the extract scavenged DPPH, NO, OH* radicals and chelated Fe(2+) in a dose-dependent manner. CONCLUSION: The inhibitory effect of Tetracarpidium conophorum leaves could be attributed to the high levels of quercitrin, quercetin and luteolin and the mechanism through which these compounds possibly do this, could be by their radical scavenging abilities.

Effect of homopterocarpin, an isoflavonoid from Pterocarpus erinaceus, on indices of liver injury and oxidative stress in acetaminophen-provoked hepatotoxicity.

BACKGROUND: Novel hepatoprotectives are needed to address the increasing cases of liver problems worldwide. Pterocarpus erinaceus Poir (Fabaceae) ethanol stem bark extract (PE) and its constituent flavonoid, homopterocarpin (HP), were investigated for their protective property in acetaminophen-induced oxidative stress and liver damage. METHODS: Adult male albino rats were divided into nine groups. Seven groups were pretreated with PE (50-, 100-, and 150 mg/kg), HP (25-, 50-, and 75 mg/kg) or silymarin (25 mg/kg), respectively, once daily for 5 consecutive days and then administered acetaminophen (2 g/kg) on the 5th day. The control and acetaminophen-intoxicated groups received normal saline throughout the experimental period, with the latter group additionally receiving 2 g/kg acetaminophen on the 5th day. Administrations were performed po. RESULTS: In the acetaminophen-intoxicated group, there were significant increases (p<0.05) in serum activities of alanine aminotransferase (31.72±3.3 vs. 22.1±1.2 U/I), aspartate aminotransferase (185.1±10.1 vs. 103.83±13.3 U/I), bilirubin level and hepatic malondialdehyde (2.32±0.3 vs. 1.42±0.1 units/mg protein), accompanied with significant decreases (p<0.05) in hepatic reduced glutathione level (0.10±0.01 vs. 0.23±0.03 units/mg protein) and glutathione peroxidase activity (2.51±0.2 vs. 3.25±0.2 µmol H2O2 consumed/min/mg protein) compared with the control. CONCLUSIONS: PE and HP ameliorated most of the observed biochemical alterations with HP appearing to show more potency. The results suggest that the flavonoid, homopterocarpin contributes to the hepatoprotective and antioxidant potentials of P. erinaceus extract.

Evaluation of the toxicological profile of the leaves and young twigs of Caesalpinia bonduc (Linn) roxb.

Acute and sub-acute toxicological effects of ethanolic extract of the leaves and young twigs of Caesalpinia bonduc were carried out on albino rats. Single extract doses from 2000 to 5000 mg/kg body weight were administered orally and monitored for 14 days in acute study, while extract doses from 200 to 1600 mg/kg body weight were orally administered daily for 28 days in sub-acute study and recovery was assessed 14 days after dosing. Biochemical, haematological and histopathological examinations were carried out. There was no mortality in the experimental animals in all acute treatment doses. However, there were significant alterations in the biomarkers and induced cellular damage to the liver in all acute treatment doses. In the sub-acute toxicity treatment, the assessed biomarkers were unaffected at extract dose of 200 mg/kg body weight compared to control, while significant changes were observed in rats administered with extract doses of 400 mg/kg body weight and above. No significant difference was observed between the tested groups and the recovery groups in the sub-acute toxicity study. In conclusion, the ethanolic extract of C. bonduc could be toxic to selected organs of the rat body in acute and sub-acute treatments.

Inhibitory Effect of Aqueous Extract of Stem Bark of Cissus populnea on Ferrous Sulphate- and Sodium Nitroprusside-Induced Oxidative Stress in Rat's Testes In Vitro.

Cissus populnea are plants associated with a myriad of medicinal uses in different parts of the world and are good sources of carotenoids, triterpenoids, and ascorbic acid. The antioxidant properties and inhibitory effect of water extractible phytochemicals from stem bark of C. populnea on FeSO(4) and sodium nitroprusside- (SNP-) induced lipid peroxidation in rat testes were investigated in vitro. The results revealed that the extract was able to scavenge DPPH radical, chelate Fe(2+) and also had a high reducing power. Furthermore, the incubation of the testes tissue homogenate in the presence of FeSO(4) and SNP, respectively, caused a significant increase in the malondialdehyde (MDA) contents of the testes. However, the aqueous extract of the stem bark of C. populnea caused a significant decrease in the MDA contents of both Fe(2+) (EC(50) = 0.027 mg/mL) and SNP- (EC(50) = 0.22 mg/mL) induced lipid peroxidation in the rat testes homogenates in a dose-dependent manner. The water extractible phytochemicals from C. populnea protect the testes from oxidative stress and this could be attributed to their high antioxidant activity: DPPH-scavenging ability, Fe(2+)-chelating and -reducing power. Therefore, oxidatively stress in testes could be potentially managed/prevented by this plant.

Antioxidant activity and hepatoprotective property of leaf extracts of Boerhaavia diffusa Linn against acetaminophen-induced liver damage in rats.

Extracts of Boerhaavia diffusa leaves were evaluated for antioxidant and hepatoprotective properties in the acetaminophen-induced liver damage model. Antioxidative evaluation of ethanolic extract gave total phenolic content, total flavonoid content, vitamin C content and vitamin E content and the levels of selenium and zinc as 6.6+/-0.2mg/g tannic acid equivalent, 0.092+/-0.003 mg/g quercetin equivalent, 0.21+/-0.03 mg/g, 0.054+/-0.002 mg/g, 0.52+/-0.05 ppm and 9.28+/-0.16 ppm, respectively. The DPPH scavenging capacity and the reductive potential were 78.32+/-2.41% and 0.65+/-0.02 mg/g ascorbic acid, respectively. Pretreatment with aqueous and ethanolic extracts decreased the activities of alkaline phosphatase, lactate dehydrogenase, alanine aminotransferase, aspartate aminotransferase, and the level of bilirubin in the serum that were elevated by acetaminophen. The two extracts also ameliorated the elevation in the activities of the enzymes in the liver. Acetaminophen intoxication led to reduction in serum and liver albumin levels which were not significantly increased by pretreatment with the extracts. The extracts also protected against acetaminophen induced lipid peroxidation. These results indicated that leaf extracts from B. diffusa possess hepatoprotective property against acetaminophen-induced liver damage which may be mediated through augmentation of antioxidant defenses.