In-vivo assessment of the protection of Beta-glucans of Pleurotus ostreatus against oxidative stress caused by acrylamide intake (part II) / Evaluación in vivo de la proteccion de los beta-glucanos de Pleurotus ostreatus contra el estrés oxidativo causado por la ingesta de acrilamida (parte II)

INTRODUCTION: in April 2002, the National Food Authority of Sweden published a study in which the presence of a carcinogen was reported for the first time in experimental animals, and was identified as acrylamide. Various studies have shown that the β-glucans of Pleurotus ostreatus have diverse biological properties including antioxidant and anticancer activities. METHODS: β-glucans were obtained by alkaline-acid hydrolysis from Pleurotus ostreatus, and their content was characterized by liquid chromatography. To evaluate the effect of β-glucans on the expression of glutathione, Balb/c mice were used, and 4 test groups were established. All groups were fed as usual, groups treated with acrylamide were administered the compound intragastrically at a concentration of 50 μg/mL, and β-glucan treatment was given at a concentration of 50 μg/mL. RESULTS: no mortality was observed after exposure to the tested dose of acrylamide; only signs of peripheral neuropathy such as hyperactivity and tremors were observed after five days of experimentation, and were maintained over 30 days after the experiment. On the other hand, an increase in lipid peroxidation levels was observed in the livers of the acrylamide-treated mice, which were lower in the mice treated with β-glucans. CONCLUSIONS: results show that β-glucans may act as antioxidant agents able to protect the liver against oxidative stress as caused by the intake of acrylamide

INTRODUCCIÓN: en abril de 2002, la Autoridad Nacional de Alimentos de Suecia publicó un estudio en el que se informó por primera vez de la presencia de un carcinógeno en animales experimentales, identificado como acrilamida. Diversos estudios han demostrado que los β-glucanos de Pleurotus ostreatus tienen diversas propiedades biológicas, tales como actividades antioxidantes y anticancerígenas. MÉTODOS: los β-glucanos se obtuvieron por hidrólisis ácido-alcalina de Pleurotus ostreatus y su contenido se caracterizó por cromatografía líquida. Para evaluar el efecto de los β-glucanos sobre la expresión de glutatión, se usaron ratones Balb/c y se establecieron 4 grupos de prueba; todos los grupos se alimentaron normalmente, en los grupos tratados con acrilamida esta se administró intragástricamente a una concentración de 50 μg/mL, y el tratamiento con β-glucanos se dio a una concentración de 50 μg/mL. RESULTADOS: no se observó mortalidad después de la exposición a la dosis probada de acrilamida; solo se observaron signos de neuropatía periférica, como hiperactividad y temblores, después de cinco días de experimentación, que se mantuvieron dentro de los 30 días posteriores al experimento. Por otro lado, se observó un aumento de los niveles de peroxidación lipídica en los hígados de los ratones tratados con acrilamida, que fueron más bajos en los ratones tratados con β-glucanos. CONCLUSIONES: los resultados muestran que los β-glucanos podrían actuar como agentes antioxidantes y proteger el hígado contra el estrés oxidativo causado por la ingesta de acrilamida

Phytochemical screening and hepatoprotective potential of Niphidium albopunctatissimum Lellinger on alcoholic hepatoxicity induced in albino rats / Tamizaje fitoquímico y potencial hepatoprotector de Niphidium albopunctatissimum Lellinger en la hepatoxicidad alcohólica inducida en ratas albinas

OBJECTIVES: To identify the phytoconstituents and determine the effect of Niphidium albopunctatissimum Lellinger on alcoholic hepatoxicity induced in albino rats. METHODS: Phytochemical screening was performed using the drop Test. For hepatoxicity study, albino rats were randomized into 5 groups of 6 each. Healthy group: without hepatoxicity; Control group: hepatotoxicity; Curative group: hepatotoxicity plus fluid extract of N. albopunctatissimum Lellinger; Standard group: hepatotoxicity plus silymarin; Preventive group: Fluid extract of N. albopunctatissimum Lellinger for one week, then hepatotoxicity. Hepatotoxicity was induced with 56% (w / v) ethanol at doses of 7.6 mL / kg p.c every 12 hours for 7 days. Glutamic pyruvic transaminase (GPT) values were determined at baseline, 7 days after induction and 14 days after. A histopathological study of the livers was performed. RESULTS: Phytochemical screening revealed the presence of polyphenols, anthocyanidins, saponins, flavonoids and tannins. The preventive and standard groups showed a very significant decrease in serum GPT levels compared to control group (p < 0.01), and curative group did so significantly (p < 0.05). Histopathological analysis showed in curative group some degenerating hepatocytes, many with normal-looking cytoplasm; the preventive and standard groups presented hepatocytes with normal architecture and some in degeneration, unlike the evident degeneration and necrosis in control group. CONCLUSION: Niphidium albopunctatissimum Lellinger may have hepatoprotective potential against alcoholic toxicity induced in albino rats

OBJETIVOS: Identificar los fitoconstituyentes y determinar el efecto de Niphidium albopunctatissimum Lellingeren la hepatoxicidad alcohólica inducida en ratas albinas. MÉTODOS: El tamizaje fitoquímico se realizó mediante la Prueba de la gota. Para el efecto en la hepatoxicidad, las ratas albinas fueron distribuidas al azar en 5 grupos de 6 cada uno, Grupo sano: Sin hepatoxicidad, Grupo Control: hepatotoxicidad, Grupo Curativo: hepatotoxicidad más extracto fluído de N. albopunctatissimum Lellinger, Grupo Patrón: hepatotoxicidad más silimarina y Grupo Preventivo: extracto fluido de N. albopunctatissimum Lellinger por una semana, luego hepatotoxicidad. La hepatotoxicidad se indujo con etanol 56% (p/v) en dosis de 7,6 mL/kg p.c cada 12 horas por 7 días. Se determinaron valores de Glutámico pirúvica transaminasa (GPT) al inicio, a los 7 días de inducción y a los 14 días. Se realizó el estudio histopatológico a los hígados. RESULTADOS: El tamizaje fitoquímico reveló presencia de polifenoles, antocianidinas, saponinas, flavonoides y taninos. Los grupos preventivo y patrón evidenciaron disminución muy significativa de niveles séricos de GPT en comparación con el grupo control (p< 0,01), y el grupo curativo lo hizo de manera significativa (p < 0,05). El análisis histopatológico evidenció en el grupo curativo algunos hepatocitos en degeneración, muchos con citoplasma de aspecto normal; los grupos preventivo y patrón presentaron hepatocitos con arquitectura normal y algunos en degeneración, a diferencia de la evidente degeneración y necrosis en el grupo control. CONCLUSIÓN: Niphidium albopunctatissimum Lellinger puede tenerpotencial hepatoprotector frente a la toxicidad alcohólica inducida en ratas albinas

Hepatoprotective effects of melatonin against pronecrotic cellular events in streptozotocin-induced diabetic rats

Oxidative stress-mediated damage to liver tissue underlies the pathological alterations in liver morphology and function that are observed in diabetes. We examined the effects of the antioxidant action of melatonin against necrosis-inducing DNA damage in hepatocytes of streptozotocin (STZ)-induced diabetic rats. Daily administration of melatonin (0.2 mg/kg) was initiated 3 days before diabetes induction and maintained for 4 weeks. Melatonin-treated diabetic rats exhibited improved markers of liver injury (P < 0.05), alkaline phosphatase, and alanine and aspartate aminotransferases. Melatonin prevented the diabetes-related morphological deterioration of hepatocytes, DNA damage (P < 0.05), and hepatocellular necrosis. The improvement was due to containment of the pronecrotic oxygen radical load, observed as inhibition (P < 0.05) of the diabetes-induced rise in lipid peroxidation and hydrogen peroxide increase in the liver. This was accompanied by improved necrotic markers of cellular damage: a significant reduction in cleavage of the DNA repair enzyme poly(ADP-ribose) polymerase 1 (PARP-1) into necrotic 55- and 62-kDa fragments, and inhibition of nucleus-to-cytoplasm translocation and accumulation in the serum of the high-mobility group box 1 (HMGB1) protein. We conclude that melatonin is hepatoprotective in diabetes. It reduces extensive DNA damage and resulting necrotic processes. Melatonin application could thus present a viable therapeutic option in the management of diabetes-induced liver injury

Aqueous date fruit extract protects against lipid peroxidation and improves antioxidant status in the liver of rats subchronically exposed to trichloroacetic acid

Trichloroacetic acid (TCA) is a prominent by-product of the chlorination of drinking water. It induces cell damage by producing free radicals and reactive oxygen species. The present study was carried out to evaluate the potential hepatoprotective role of the aqueous date extract (ADE) against TCA-induced liver injury. Forty-eight male Wistar rats were randomly divided into six groups of eight: group I served as the control; group II was given ADE by gavage; groups III and IV received TCA as drinking water at 0.5 and 2 g/L, respectively; and groups V and VI were treated with ADE by gavage and then received TCA at 0.5 and 2 g/L, respectively, as drinking water. The experiment was performed for 2 months. The hepatotoxicity of TCA administration was revealed by an increase in the levels of hepatic marker enzymes (transaminases, gamma-glutamyl transferase, and lactate dehydrogenase) and conjugated bilirubin and a decrease in albumin level. The TCA administration induced also significant elevation of the malondialdehyde (MDA) level and the antioxidant activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx) paralleled with a significant decline in catalase (CAT) activity. These biochemical alterations were accompanied by histological changes marked by the appearance of vacuolization, necrosis, congestion, inflammation, and enlargement of sinusoids in the liver section. Treatment with date palm fruit extract restored the liver damage induced by TCA, as demonstrated by inhibition of hepatic lipid peroxidation; amelioration of SOD, GPx, and CAT activities; and improvement of histopathology changes. These results suggest that ADE has a protective effect over TCA-induced oxidative damage in rat liver

Hypoglycemic and hepatoprotective activity of Rosmarinus officinalis extract in diabetic rats

The present study examined the effect of water extract (200 mg/kg body weight) of Rosmarinus officinalis L. in streptozotocin (STZ)-induced diabetic rats for 21 days. The hepatoprotective effects were investigated in the liver tissues sections. There was a significant increase in serum liver biochemical parameters (aspartate aminotransferase, alanine transaminase, and alkaline phosphatase), accompanied by a significant decrease in the level of total protein and albumin in the STZ-induced rats when compared with that of the normal group. The high-dose treatment group (200 mg/kg body wt) significantly restored the elevated liver function enzymes near to normal. This study revealed that rosemary extracts exerted a hepatoprotective effect. The results indicate that the extract exhibits the protective effect on tissues and prove its potentials as an antidiabetic agent (AU)