Does ^2 H(2)0 Also Protect Membrane-Bound Enzymes?

Abstract

Thermal inactivation studies performed with several membrane-bound enzymes such as chitin synthase, cytochrome c oxidase, nucleotidase, as well as bacterial, mitochondrial and plasma membrane ATPases from yeast in H(2)0 and ^2 H(2)0 indicated that most of these enzymes could not be protected by ^2 H(2)0 against thermal inactivation. Only the Escherichia coli ATPase, which is located at the surface of the membrane, and the cytochrome c oxidase were stabilized by heavy water.

Successful transplantation of rat hearts subjected to extended cold preservation with a novel preservation solution

“…Modified impermeants such as mannitol and sucrose, which per se have cyto‐protective [15] and anti‐oxidative effects [16], could reduce organ swelling. Other properties of D 2 O, in addition to the inhibition of Ca 2+ ‐overload, such as stabilization of the microtubules [18], actin cytoskeleton [19], plasma membrane [20], and membrane‐bound proteins [21], could help Dsol to inhibit graft injury.…”

“…Calpain also triggers apoptosis by caspase-12 activation [41], and Bid [42] and Bax cleavage [43], followed by caspase 3 activation. Among the many unique properties of D 2 O, such as stabilization of the microtubules [18], actin cytoskeleton [19], plasma membrane [20], and membrane-bound proteins [21], we focused on the ability of D 2 O to suppress the elevation of cytosolic Ca 2+ concentration [17]. D 2 O is reported to inhibit calcium influx via the plasma membrane L-type Ca 2+ channel [44] as well as calcium efflux from the sarcoplasmic reticulum (SR) to the cytosol [45].…”

“…In addition, the impermeants sucrose and mannitol, which cost less than raffinose, are expected to give the solution potent cellular protection and antioxidant effects [15,16]. Deuterium oxide (D 2 O) has unique biological effects, including inhibition of cytosolic Ca 2+ overload [17], and the stabilization of microtubules [18], actin cytoskeleton [19], plasma membrane [20], and membrane‐bound proteins [21]. D 2 O also accelerates ATP production by stimulation of glucose uptake, glycolysis [22], and mitochondrial respiration [23].…”