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Informacje o czasopiśmie
Format
Czasopismo
eISSN
1337-9569
Pierwsze wydanie
19 Jun 2009
Częstotliwość wydawania
4 razy w roku
Języki
Angielski

Wyszukiwanie

Tom 8 (2015): Zeszyt 3 (September 2015)

Informacje o czasopiśmie
Format
Czasopismo
eISSN
1337-9569
Pierwsze wydanie
19 Jun 2009
Częstotliwość wydawania
4 razy w roku
Języki
Angielski

Wyszukiwanie

7 Artykułów
Otwarty dostęp

The neurochemical profile of the hippocampus in isoflurane-treated and unanesthetized rat pups

Data publikacji: 07 Mar 2016
Zakres stron: 113 - 117

Abstrakt

Abstract

In vivo study of cerebral metabolism in neonatal animals by high-resolution magnetic resonance spectroscopy (MRS) is an important tool for deciphering the developmental origins of adult diseases. Up to date, all in vivo spectrum acquisition procedures have been performed in neonatal rodents under anesthesia. However, it is still unknown if the inhaled anesthetic isoflurane, which is commonly used in magnetic resonance imaging studies, could affect metabolite levels in the brain of neonatal rats. Moreover, the unanesthetized MRS preparation that uses neonatal rodent pups is still lacking.

Here, a novel restraint protocol was developed for neonatal rats in accordance with the European Directive 2010/63/EU. This protocol shares the same gradation of severity as the protocol for non-invasive magnetic resonance imaging of animals with appropriate sedation or anesthesia. Such immobilization of neonatal rats without anesthesia can be implemented for MRS studies when an interaction between anesthetic and target drugs is expected. Short-term isoflurane treatment did not affect the levels of key metabolites in the hippocampi of anesthetized pups and, in contrast to juvenile and adult rodents, it is suitable for MRS studies in neonatal rats when the interaction between anesthetic and target drugs is not expected.

Słowa kluczowe

  • neonatal rat
  • unanesthetized
  • isoflurane
  • hippocampus
  • magnetic resonance spectroscopy
Otwarty dostęp

Damascenine induced hepatotoxicity and nephrotoxicity in mice and in vitro assessed human erythrocyte toxicity

Data publikacji: 07 Mar 2016
Zakres stron: 118 - 124

Abstrakt

Abstract

Nigella damascena seed is characterized by the presence of the major alkaloid, damascenine and its related metabolites. To our knowledge, no detailed subchronic toxicological assessment of damascenine (DA) has been reported. The present study evaluated the potential toxicity of DA in vivo after sub-chronic intraperitoneal (i.p) administration in mice and in vitro following human erythrocyte hemolysis. In vivo, a total of 48 adult male and female Swiss albino mice were used in a sub-chronic toxicity study. The mice received intraperitoneally two doses of DA (20 and 100 mg/kg) for 28 days. Food intake, body weight and central body temperature were measured during the experiment. After completion of drug treatment, biochemical and histological analyses were performed. No mortality was observed in any of the treatment groups of mice, showing no toxic effects during the study. Neither were biochemical parameters altered; no significant differences were observed concerning glucose, bilirubin, aspartate transaminase (AST), alanine aminotransferase (ALT), urea, and creatinine parameters. No histopathological alterations were found in kidney and liver structures. In vitro, we focused on the human erythrocyte hemolytic process in the presence of several concentrations of DA. High level concentration of 1 000 μg/ml of DA revealed normal cell shapes and absence of hemolysis and deformation.

Słowa kluczowe

  • Damascenine
  • hepatotoxicity
  • nephrotoxicity
  • erythrocyte
  • mice
Otwarty dostęp

Antitumor activity and antioxidant status of Streblus asper bark against Dalton's ascitic lymphoma in mice

Data publikacji: 07 Mar 2016
Zakres stron: 125 - 130

Abstrakt

Abstract

Streblus asper Lour (Moraceae), commonly known as Siamee Rough Brush in English is widely distributed in subtropical Asia and traditionally used for several medicinal purposes. In the present study, the ethyl acetate fraction of the methanol extract from Streblus asper bark (EASA) was evaluated for antitumor effect against Dalton’s ascitic lymphoma (DAL) in Swiss albino mice. Twenty-four hours after intraperitoneal inoculation of DAL cells in mice, EASA was administered intraperitoneally at 200 and 400 mg/kg body weight for 9 consecutive days. On the 10th day, half of the mice were sacrificed to determine the tumor growth parameters, and the rest were kept alive for survival assessment. Hematological, serum biochemical and tissue (liver, kidney) antioxidant profiles were also determined. EASA exhibited significant and dose dependent decrease in tumor growth parameters and increased survival of DAL bearing animals. EASA significantly and dose-dependently normalized the altered hematological, serum biochemical and tissue antioxidant parameters as compared with the DAL control mice. From the present study it may be concluded that S. asper bark possesses remarkable antitumor efficacy mediated by amelioration of oxidative stress by multiple mechanisms.

Słowa kluczowe

  • Dalton’s ascitic lymphoma (DAL)
  • antitumor
  • antioxidant
Otwarty dostęp

Zinc asparaginate supplementation induces redistribution of toxic trace elements in rat tissues and organs

Data publikacji: 07 Mar 2016
Zakres stron: 131 - 138

Abstrakt

Abstract

The primary objective of the current study was the investigation of the influence of zinc asparaginate supplementation for 7 and 14 days on toxic metal and metalloid content in rat organs and tissues. Rats obtained zinc asparaginate in doses of 5 and 15 mg/kg/day for 7 and 14 days. At the end of the experiment rat tissues and organs (liver, kidney, heart, m. gastrocnemius, serum, and hair) were collected for subsequent analysis. Estimation of Zn, Al, As, Li, Ni, Sn, Sr content in the harvested organs was performed using inductively coupled plasma mass spectrometry at NexION 300D. The obtained data showed that intragastric administration of zinc significantly increased liver, kidney and serum zinc concentrations. Seven-day zinc treatment significantly affected the toxic trace element content in the animals’ organs. Zinc supplementation significantly decreased particularly liver aluminium, nickel, and tin content, whereas lead tended to increase. Zinc-induced changes in kidney metal content were characterized by elevated lithium and decreased nickel concentration. Zinc-induced alteration of myocardical toxic element content was multidirectional. Muscle aluminium and lead concentration were reduced in response to zinc supplementation. At the same time, serum and hair toxic element concentrations remained relatively stable after 7-day zinc treatment. Zinc asparaginate treatment of 14 days significantly depressed liver and elevated kidney lithium content, whereas a significant zinc-associated decrease was detected in kidney strontium content. Zinc supplementation for 14 days resulted also in multidirectional changes in the content of heart toxic elements. At the same time, significant zinc-associated decrease in muscle lithium and nickel levels was observed. Fourteen-day zinc treatment resulted in significantly increased serum arsenic and tin concentrations, whereas hair trace element content remained relatively stable. Generally, the obtained data indicate a significant redistribution of toxic metals in the animal organism under zinc supplementation.

Słowa kluczowe

  • zinc
  • metal distribution
  • toxic trace elements
  • antagonism
  • lithium
Otwarty dostęp

Local salt substitutes “Obu-otoyo” activate acetylcholinesterase and butyrylcholinesterase and induce lipid peroxidation in rat brain

Data publikacji: 07 Mar 2016
Zakres stron: 139 - 145

Abstrakt

Abstract

Evidence has shown that ingestion of heavy metals can lead to neurodegenerative diseases. This study aimed to investigate the neurotoxic potential of salt substitutes (Obu-Otoyo); salt A (made by burning palm kernel shaft then soaked in water overnight and the extract from the resulting residue is used as the salt substitute) and salt B (an unrefined salt mined from a local site at Ilobu town, Osun-State, Nigeria) by assessing their effect on some key enzymes linked with neurodegenerative disease [acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities] as well as on malondialdehyde (MDA) content of the rat brain. Salt substitutes were fed to normal rats as dietary inclusion at doses of 0.5 and 1.0% for 30 days. Thereafter, the effect of the salt substitutes on AChE and BChE activities as well as on MDA level in the rat brain was determined. The results revealed that the salt substitutes caused a significant (p<0.05) increase in both AChE and BChE activity and also induced lipid peroxidation in the brain of rats in vivo as well as under in vitro condition in a dose-dependent manner. The effect of the salt substitutes on AChE and BChE activities could be attributed to the presence of some toxic heavy metals. Therefore, the ability of the salt substitutes to induce lipid peroxidation and activate AChE and BChE activities could provide some possible mechanism for their neurotoxic effect.

Słowa kluczowe

  • Obu-Otoyo
  • lipid peroxidation
  • heavy metals
  • acetylcholinesterase
  • butyrylcholinesterase
Otwarty dostęp

Blood level of cadmium and lead in occupationally exposed persons in Gwagwalada, Abuja, Nigeria

Data publikacji: 07 Mar 2016
Zakres stron: 146 - 150

Abstrakt

Abstract

This study was designed to assess the blood levels of cadmium and lead in some occupationally exposed individuals and compare the values with non-exposed individuals, with the aim of increasing the awareness of health risk caused by these heavy metals. A total of 120 subjects (64 occupationally exposed and 56 non-exposed subjects) with the age range of 15–40 years were studied in cross-sectional study conducted between September 2012 and February 2013 in Gwagwalada area of Abuja, Nigeria. Blood cadmium and lead were analyzed using an atomic absorption spectrophotometer (AAS). The respective mean blood levels of cadmium and lead were 11.63±1.73 μg/dl and 45.43±6.93 μg/dl in occupationally-exposed subjects, while in non-exposed subjects 2.03±0.55 μg/dl and 12.08±2.87 μg/dl. The results show that occupational exposure increases the blood level of cadmium and lead, which consequently increases the health risk of the exposed individuals.

Słowa kluczowe

  • lead
  • cadmium
  • occupational exposure
  • atomic absorption spectrophotometer
  • heavy metals in blood
Otwarty dostęp

Effect of chronic exposure to cadmium on serum lipid, lipoprotein and oxidative stress indices in male rats

Data publikacji: 07 Mar 2016
Zakres stron: 151 - 154

Abstrakt

Abstract

Cadmium (Cd) is an environmental toxic metal implicated in lipid abnormalities. The present study was designed to elucidate the possible association between chronic exposure to Cd concentration and alterations in plasma lipid, lipoprotein, and oxidative stress indices in rats. Sixteen male rats were assigned to 2 groups of 8 rats each (test and control). The Cd-exposed group obtained drinking water containing cadmium chloride (CdCl2) in the concentration of 2.0 mg Cd/L in drinking water for 3 months. At the end of the experimental period, blood samples were obtained to determine the changes of serum triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), reduced glutathione (GSH), malondialdehyde (MDA) and also serum Cd contents. The results of the present study indicated that Cd administration significantly increased the serum levels of TG, TC, LDL-C, MDA and Cd with reduction in the HDL-C and GSH levels. In conclusion, evidence is presented that chronic exposure to low Cd concentration can adversely affect the lipid and lipoprotein profile via lipid peroxidation.

Słowa kluczowe

  • cadmium
  • lipoprotein
  • oxidative stress
  • lipid
7 Artykułów
Otwarty dostęp

The neurochemical profile of the hippocampus in isoflurane-treated and unanesthetized rat pups

Data publikacji: 07 Mar 2016
Zakres stron: 113 - 117

Abstrakt

Abstract

In vivo study of cerebral metabolism in neonatal animals by high-resolution magnetic resonance spectroscopy (MRS) is an important tool for deciphering the developmental origins of adult diseases. Up to date, all in vivo spectrum acquisition procedures have been performed in neonatal rodents under anesthesia. However, it is still unknown if the inhaled anesthetic isoflurane, which is commonly used in magnetic resonance imaging studies, could affect metabolite levels in the brain of neonatal rats. Moreover, the unanesthetized MRS preparation that uses neonatal rodent pups is still lacking.

Here, a novel restraint protocol was developed for neonatal rats in accordance with the European Directive 2010/63/EU. This protocol shares the same gradation of severity as the protocol for non-invasive magnetic resonance imaging of animals with appropriate sedation or anesthesia. Such immobilization of neonatal rats without anesthesia can be implemented for MRS studies when an interaction between anesthetic and target drugs is expected. Short-term isoflurane treatment did not affect the levels of key metabolites in the hippocampi of anesthetized pups and, in contrast to juvenile and adult rodents, it is suitable for MRS studies in neonatal rats when the interaction between anesthetic and target drugs is not expected.

Słowa kluczowe

  • neonatal rat
  • unanesthetized
  • isoflurane
  • hippocampus
  • magnetic resonance spectroscopy
Otwarty dostęp

Damascenine induced hepatotoxicity and nephrotoxicity in mice and in vitro assessed human erythrocyte toxicity

Data publikacji: 07 Mar 2016
Zakres stron: 118 - 124

Abstrakt

Abstract

Nigella damascena seed is characterized by the presence of the major alkaloid, damascenine and its related metabolites. To our knowledge, no detailed subchronic toxicological assessment of damascenine (DA) has been reported. The present study evaluated the potential toxicity of DA in vivo after sub-chronic intraperitoneal (i.p) administration in mice and in vitro following human erythrocyte hemolysis. In vivo, a total of 48 adult male and female Swiss albino mice were used in a sub-chronic toxicity study. The mice received intraperitoneally two doses of DA (20 and 100 mg/kg) for 28 days. Food intake, body weight and central body temperature were measured during the experiment. After completion of drug treatment, biochemical and histological analyses were performed. No mortality was observed in any of the treatment groups of mice, showing no toxic effects during the study. Neither were biochemical parameters altered; no significant differences were observed concerning glucose, bilirubin, aspartate transaminase (AST), alanine aminotransferase (ALT), urea, and creatinine parameters. No histopathological alterations were found in kidney and liver structures. In vitro, we focused on the human erythrocyte hemolytic process in the presence of several concentrations of DA. High level concentration of 1 000 μg/ml of DA revealed normal cell shapes and absence of hemolysis and deformation.

Słowa kluczowe

  • Damascenine
  • hepatotoxicity
  • nephrotoxicity
  • erythrocyte
  • mice
Otwarty dostęp

Antitumor activity and antioxidant status of Streblus asper bark against Dalton's ascitic lymphoma in mice

Data publikacji: 07 Mar 2016
Zakres stron: 125 - 130

Abstrakt

Abstract

Streblus asper Lour (Moraceae), commonly known as Siamee Rough Brush in English is widely distributed in subtropical Asia and traditionally used for several medicinal purposes. In the present study, the ethyl acetate fraction of the methanol extract from Streblus asper bark (EASA) was evaluated for antitumor effect against Dalton’s ascitic lymphoma (DAL) in Swiss albino mice. Twenty-four hours after intraperitoneal inoculation of DAL cells in mice, EASA was administered intraperitoneally at 200 and 400 mg/kg body weight for 9 consecutive days. On the 10th day, half of the mice were sacrificed to determine the tumor growth parameters, and the rest were kept alive for survival assessment. Hematological, serum biochemical and tissue (liver, kidney) antioxidant profiles were also determined. EASA exhibited significant and dose dependent decrease in tumor growth parameters and increased survival of DAL bearing animals. EASA significantly and dose-dependently normalized the altered hematological, serum biochemical and tissue antioxidant parameters as compared with the DAL control mice. From the present study it may be concluded that S. asper bark possesses remarkable antitumor efficacy mediated by amelioration of oxidative stress by multiple mechanisms.

Słowa kluczowe

  • Dalton’s ascitic lymphoma (DAL)
  • antitumor
  • antioxidant
Otwarty dostęp

Zinc asparaginate supplementation induces redistribution of toxic trace elements in rat tissues and organs

Data publikacji: 07 Mar 2016
Zakres stron: 131 - 138

Abstrakt

Abstract

The primary objective of the current study was the investigation of the influence of zinc asparaginate supplementation for 7 and 14 days on toxic metal and metalloid content in rat organs and tissues. Rats obtained zinc asparaginate in doses of 5 and 15 mg/kg/day for 7 and 14 days. At the end of the experiment rat tissues and organs (liver, kidney, heart, m. gastrocnemius, serum, and hair) were collected for subsequent analysis. Estimation of Zn, Al, As, Li, Ni, Sn, Sr content in the harvested organs was performed using inductively coupled plasma mass spectrometry at NexION 300D. The obtained data showed that intragastric administration of zinc significantly increased liver, kidney and serum zinc concentrations. Seven-day zinc treatment significantly affected the toxic trace element content in the animals’ organs. Zinc supplementation significantly decreased particularly liver aluminium, nickel, and tin content, whereas lead tended to increase. Zinc-induced changes in kidney metal content were characterized by elevated lithium and decreased nickel concentration. Zinc-induced alteration of myocardical toxic element content was multidirectional. Muscle aluminium and lead concentration were reduced in response to zinc supplementation. At the same time, serum and hair toxic element concentrations remained relatively stable after 7-day zinc treatment. Zinc asparaginate treatment of 14 days significantly depressed liver and elevated kidney lithium content, whereas a significant zinc-associated decrease was detected in kidney strontium content. Zinc supplementation for 14 days resulted also in multidirectional changes in the content of heart toxic elements. At the same time, significant zinc-associated decrease in muscle lithium and nickel levels was observed. Fourteen-day zinc treatment resulted in significantly increased serum arsenic and tin concentrations, whereas hair trace element content remained relatively stable. Generally, the obtained data indicate a significant redistribution of toxic metals in the animal organism under zinc supplementation.

Słowa kluczowe

  • zinc
  • metal distribution
  • toxic trace elements
  • antagonism
  • lithium
Otwarty dostęp

Local salt substitutes “Obu-otoyo” activate acetylcholinesterase and butyrylcholinesterase and induce lipid peroxidation in rat brain

Data publikacji: 07 Mar 2016
Zakres stron: 139 - 145

Abstrakt

Abstract

Evidence has shown that ingestion of heavy metals can lead to neurodegenerative diseases. This study aimed to investigate the neurotoxic potential of salt substitutes (Obu-Otoyo); salt A (made by burning palm kernel shaft then soaked in water overnight and the extract from the resulting residue is used as the salt substitute) and salt B (an unrefined salt mined from a local site at Ilobu town, Osun-State, Nigeria) by assessing their effect on some key enzymes linked with neurodegenerative disease [acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities] as well as on malondialdehyde (MDA) content of the rat brain. Salt substitutes were fed to normal rats as dietary inclusion at doses of 0.5 and 1.0% for 30 days. Thereafter, the effect of the salt substitutes on AChE and BChE activities as well as on MDA level in the rat brain was determined. The results revealed that the salt substitutes caused a significant (p<0.05) increase in both AChE and BChE activity and also induced lipid peroxidation in the brain of rats in vivo as well as under in vitro condition in a dose-dependent manner. The effect of the salt substitutes on AChE and BChE activities could be attributed to the presence of some toxic heavy metals. Therefore, the ability of the salt substitutes to induce lipid peroxidation and activate AChE and BChE activities could provide some possible mechanism for their neurotoxic effect.

Słowa kluczowe

  • Obu-Otoyo
  • lipid peroxidation
  • heavy metals
  • acetylcholinesterase
  • butyrylcholinesterase
Otwarty dostęp

Blood level of cadmium and lead in occupationally exposed persons in Gwagwalada, Abuja, Nigeria

Data publikacji: 07 Mar 2016
Zakres stron: 146 - 150

Abstrakt

Abstract

This study was designed to assess the blood levels of cadmium and lead in some occupationally exposed individuals and compare the values with non-exposed individuals, with the aim of increasing the awareness of health risk caused by these heavy metals. A total of 120 subjects (64 occupationally exposed and 56 non-exposed subjects) with the age range of 15–40 years were studied in cross-sectional study conducted between September 2012 and February 2013 in Gwagwalada area of Abuja, Nigeria. Blood cadmium and lead were analyzed using an atomic absorption spectrophotometer (AAS). The respective mean blood levels of cadmium and lead were 11.63±1.73 μg/dl and 45.43±6.93 μg/dl in occupationally-exposed subjects, while in non-exposed subjects 2.03±0.55 μg/dl and 12.08±2.87 μg/dl. The results show that occupational exposure increases the blood level of cadmium and lead, which consequently increases the health risk of the exposed individuals.

Słowa kluczowe

  • lead
  • cadmium
  • occupational exposure
  • atomic absorption spectrophotometer
  • heavy metals in blood
Otwarty dostęp

Effect of chronic exposure to cadmium on serum lipid, lipoprotein and oxidative stress indices in male rats

Data publikacji: 07 Mar 2016
Zakres stron: 151 - 154

Abstrakt

Abstract

Cadmium (Cd) is an environmental toxic metal implicated in lipid abnormalities. The present study was designed to elucidate the possible association between chronic exposure to Cd concentration and alterations in plasma lipid, lipoprotein, and oxidative stress indices in rats. Sixteen male rats were assigned to 2 groups of 8 rats each (test and control). The Cd-exposed group obtained drinking water containing cadmium chloride (CdCl2) in the concentration of 2.0 mg Cd/L in drinking water for 3 months. At the end of the experimental period, blood samples were obtained to determine the changes of serum triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), reduced glutathione (GSH), malondialdehyde (MDA) and also serum Cd contents. The results of the present study indicated that Cd administration significantly increased the serum levels of TG, TC, LDL-C, MDA and Cd with reduction in the HDL-C and GSH levels. In conclusion, evidence is presented that chronic exposure to low Cd concentration can adversely affect the lipid and lipoprotein profile via lipid peroxidation.

Słowa kluczowe

  • cadmium
  • lipoprotein
  • oxidative stress
  • lipid

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