Effect of heparin treatment on the expression and activity of different ion-motive P-type ATPase isoforms from mouse extensor digitorum longus muscle during degeneration and regeneration after Bothrops jararacussu venom injection

Abstract

Ca(2+) ions are essential to myonecrosis, a serious complication of snake envenomation, and heparin seems to counteract this effect. We investigated the effect of local injection of Bothrops jararacussu venom in mouse fast-twitch extensor digitorum longus (EDL) muscle, without or with heparin, on functional/molecular alterations of two central proteins involved in intracellular Ca(2+) homeostasis, sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA) and Na(+)/K(+)-ATPase. EDL-specific SERCA1 isoform expression dropped significantly just after venom administration (up to 60% compared to control EDL values at days 1 and 3; p<0.05) while SERCA2 and Na(+)/K(+)-ATPase alpha(1) isoform expression increased at the same time (3-6- and 2-3-fold, respectively; p<0.05). Although not significant, Na(+)/K(+)-ATPase alpha(2) isoform followed the same trend. Except for SERCA2, all proteins reached basal levels at the 7th day. Intravenous heparin treatment did not affect these profiles. Ca(2+)-ATPase activity was also decreased during the first days after venom injection, but here heparin was effective to reinstate activity to control levels within 3 days. We also showed that B. jararacussu venom directly inhibited Ca(2+)-ATPase activity in a concentration-dependent manner. Our results indicate that EDL SERCA and Na(+)/K(+)-ATPase are importantly affected by B. jararacussu venom and heparin has protective effect on activity but not on protein expression.

Exploring the ability of low-level laser irradiation to reduce myonecrosis and increase Myogenin transcription after Bothrops jararacussu envenomation

“…The prevalence of snakebites in Latin America is inflicted largely by pit vipers belonging to Viperidae, subfamily Crotalinae, and species of the Bothrops genus [3,4]. In Brazil, envenoming by ophidian accidents is a societal burden, mainly affecting workers of the deep countryside [5]. The hands, ankles, and legs are the body regions more subjected to bites of snakes, and skeletal muscle is the main tissue affected by Bothropic envenomation.…”

Kcnh2 and Kcnj8 interactively regulate skin wound healing and regeneration

“…For example, during early but not late stages of embryogenesis mammals regenerate their skin wounds without scars. 7 Mazzalupo and colleagues have shown that when a wound is induced in the skin of a normal developing mouse between embryonic days of development [11][12][13][14] (E11-E14), the wound completely closes and fully regenerates in less than 18 hours after wound induction. In contrast, when the wound is induced after embryonic day E14.5-adulthood, the wound closure is delayed, is not able to regenerate and a scar is formed instead.…”

“…This suggests that H+ flux serves as “high‐level master regulator” that initiates very complex and coherent downstream growth and patterning events . The role of ion channels, in promoting scarless wound healing and/or regeneration in mammals however is not yet defined except for the role of one ion channel gene, SERCA, implied in muscle regeneration …”

“…11 The role of ion channels, in promoting scarless wound healing and/or regeneration in mammals however is not yet defined except for the role of one ion channel gene, SERCA, implied in muscle regeneration. 14…”

Effects of Diene Valepotriates from Valeriana glechomifolia on Na+/K+-ATPase Activity in the Cortex and Hippocampus of Mice

“…ATPase activity was evaluated colorimetrically by measuring the amount of inorganic phosphate (Pi) released from ATP hydrolysis as reported [68]. The assay was performed at 37°C for 1 h. The reaction was started by adding 10 µg protein of each preparation to a medium consisting of 84 mM NaCl, 3 mM MgCl 2 , 3 mM ATPNa 2 , 10 mM NaN 3 , 1 mM EGTA, and 20 mM maleate-Tris buffer, pH 7.4, with 10 mM KCl (total activity) or 1 mM ouabain (ouabain-resistant activity).…”