Limits...
Mitochondrial ATPase activity and membrane fluidity changes in rat liver in response to intoxication with buckthorn (Karwinskia humboldtiana).

Cid-Hernández M, Ramírez-Anguiano AC, Ortiz GG, Morales-Sánchez EW, González-Ortiz LJ, Velasco-Ramírez SF, Pacheco-Moisés FP - Biol. Res. (2015)

Bottom Line: On the other hand, membrane fluidity was hardly affected on day 7 after treatment with Kh.Surprisingly, the pH gradient driven by ATPase activity was significantly higher than controls despite an diminution of the hydrolytic activity of ATPase.The changes in ATPase activity and pH gradient driven by ATPase activity suggest an adaptive condition whereby the fluidity of the membrane is altered.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Química, Centro Universitario de Ciencias Exactas e Ingenierías, Universidad de Guadalajara, Blvd. Marcelino García Barragán 1421, 44430, Guadalajara, Jalisco, Mexico. sagitario_garita_mar@hotmail.com.

ABSTRACT

Background: Karwinskia humboldtiana (Kh) is a poisonous plant of the rhamnacea family. To elucidate some of the subcellular effects of Kh toxicity, membrane fluidity and ATPase activities as hydrolytic and as proton-pumping activity were assessed in rat liver submitochondrial particles. Rats were randomly assigned into control non-treated group and groups that received 1, 1.5 and 2 g/Kg body weight of dry powder of Kh fruit, respectively. Rats were euthanized at day 1 and 7 after treatment.

Results: Rats under Kh treatment at all dose levels tested, does not developed any neurologic symptoms. However, we detected alterations in membrane fluidity and ATPase activity. Lower dose of Kh on day 1 after treatment induced higher mitochondrial membrane fluidity than control group. This change was strongly correlated with increased ATPase activity and pH gradient driven by ATP hydrolysis. On the other hand, membrane fluidity was hardly affected on day 7 after treatment with Kh. Surprisingly, the pH gradient driven by ATPase activity was significantly higher than controls despite an diminution of the hydrolytic activity of ATPase.

Conclusions: The changes in ATPase activity and pH gradient driven by ATPase activity suggest an adaptive condition whereby the fluidity of the membrane is altered.

Show MeSH

Related in: MedlinePlus

Relative membrane fluidity in submitochondrial particles from rats subjected to the indicated dose ofKarwinskia humboldtiana. Relative membrane fluidity, as fold induction, was calculated by normalization of values to their respective controls (0.63 ± 0.04). Control value was fixed at 1.0. The bar indicates the mean ± S.E. ***indicate a significant difference from the control group (P < 0.001).
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4376499&req=5

Fig1: Relative membrane fluidity in submitochondrial particles from rats subjected to the indicated dose ofKarwinskia humboldtiana. Relative membrane fluidity, as fold induction, was calculated by normalization of values to their respective controls (0.63 ± 0.04). Control value was fixed at 1.0. The bar indicates the mean ± S.E. ***indicate a significant difference from the control group (P < 0.001).

Mentions: To assess the acute effects of Kh on membrane fluidity and ATPase activities, from each group, half of the rats were euthanized on day 1 and the remaining half at day 7 post Kh treatment. Figure 1 depicts the relative membrane fluidity of submitochondrial particles through the relative excimer/monomer (Ie/Im) ratio of DPP; the higher the Ie/Im ratio, the more fluid is the membrane. At day 1 of Kh treatment, the dose of 1 and 1.5 Kg/g increases significantly the fluidity of membranes relative to the control group. However, higher dose (2 g/Kg) does not modify substantially the fluidity of mitochondrial membranes. At day 7, membrane fluidity values in Kh-treated rats were similar to those of controls and no statistically significant differences were found.Figure 1


Mitochondrial ATPase activity and membrane fluidity changes in rat liver in response to intoxication with buckthorn (Karwinskia humboldtiana).

Cid-Hernández M, Ramírez-Anguiano AC, Ortiz GG, Morales-Sánchez EW, González-Ortiz LJ, Velasco-Ramírez SF, Pacheco-Moisés FP - Biol. Res. (2015)

Relative membrane fluidity in submitochondrial particles from rats subjected to the indicated dose ofKarwinskia humboldtiana. Relative membrane fluidity, as fold induction, was calculated by normalization of values to their respective controls (0.63 ± 0.04). Control value was fixed at 1.0. The bar indicates the mean ± S.E. ***indicate a significant difference from the control group (P < 0.001).
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4376499&req=5

Fig1: Relative membrane fluidity in submitochondrial particles from rats subjected to the indicated dose ofKarwinskia humboldtiana. Relative membrane fluidity, as fold induction, was calculated by normalization of values to their respective controls (0.63 ± 0.04). Control value was fixed at 1.0. The bar indicates the mean ± S.E. ***indicate a significant difference from the control group (P < 0.001).
Mentions: To assess the acute effects of Kh on membrane fluidity and ATPase activities, from each group, half of the rats were euthanized on day 1 and the remaining half at day 7 post Kh treatment. Figure 1 depicts the relative membrane fluidity of submitochondrial particles through the relative excimer/monomer (Ie/Im) ratio of DPP; the higher the Ie/Im ratio, the more fluid is the membrane. At day 1 of Kh treatment, the dose of 1 and 1.5 Kg/g increases significantly the fluidity of membranes relative to the control group. However, higher dose (2 g/Kg) does not modify substantially the fluidity of mitochondrial membranes. At day 7, membrane fluidity values in Kh-treated rats were similar to those of controls and no statistically significant differences were found.Figure 1

Bottom Line: On the other hand, membrane fluidity was hardly affected on day 7 after treatment with Kh.Surprisingly, the pH gradient driven by ATPase activity was significantly higher than controls despite an diminution of the hydrolytic activity of ATPase.The changes in ATPase activity and pH gradient driven by ATPase activity suggest an adaptive condition whereby the fluidity of the membrane is altered.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Química, Centro Universitario de Ciencias Exactas e Ingenierías, Universidad de Guadalajara, Blvd. Marcelino García Barragán 1421, 44430, Guadalajara, Jalisco, Mexico. sagitario_garita_mar@hotmail.com.

ABSTRACT

Background: Karwinskia humboldtiana (Kh) is a poisonous plant of the rhamnacea family. To elucidate some of the subcellular effects of Kh toxicity, membrane fluidity and ATPase activities as hydrolytic and as proton-pumping activity were assessed in rat liver submitochondrial particles. Rats were randomly assigned into control non-treated group and groups that received 1, 1.5 and 2 g/Kg body weight of dry powder of Kh fruit, respectively. Rats were euthanized at day 1 and 7 after treatment.

Results: Rats under Kh treatment at all dose levels tested, does not developed any neurologic symptoms. However, we detected alterations in membrane fluidity and ATPase activity. Lower dose of Kh on day 1 after treatment induced higher mitochondrial membrane fluidity than control group. This change was strongly correlated with increased ATPase activity and pH gradient driven by ATP hydrolysis. On the other hand, membrane fluidity was hardly affected on day 7 after treatment with Kh. Surprisingly, the pH gradient driven by ATPase activity was significantly higher than controls despite an diminution of the hydrolytic activity of ATPase.

Conclusions: The changes in ATPase activity and pH gradient driven by ATPase activity suggest an adaptive condition whereby the fluidity of the membrane is altered.

Show MeSH
Related in: MedlinePlus