Ex Vivo Metabolic Analysis of Eye Bank Corneas Using Phosphorus Nuclear Magnetic Resonance

Potential Role for Glycerylphosphorylcholine in Cryopreservation

“…Similar findings were observed when previously GPC-incubated corneas were frozen at liquid nitrogen temperatures [5]. Moreover, it was discovered that accompanying the increase in intracorneal GPC, the metabolic integrity of the cornea as measured by the energy modulus [8,9] was maintained after cryogenic treatment [6].…”

Potential Role for Glycerylphosphorylcholine in Cryopreservation

“…Similar findings were observed when previously GPC-incubated corneas were frozen at liquid nitrogen temperatures [5]. Moreover, it was discovered that accompanying the increase in intracorneal GPC, the metabolic integrity of the cornea as measured by the energy modulus [8,9] was maintained after cryogenic treatment [6].…”

Ex vivo phosphorus magnetic resonance spectroscopy on eye bank corneas and corneal metabolic health

“…The most sensitive indices are those associated with the high-energy phosphates such as ATP, because these are the first metabolites to be compromised when tissues are under stress [2,3,10]. Thus, the tissue energy modulus [7], the ratio of high-energy phosphates to low-energy phosphates, is a useful metabolic indicator of tissue health status. Healthy tissues have a modulus value in the range of 0.8 to 1.0.…”

“…Phosphorus-31 magnetic resonance spectroscopy (3~p_ MRS) allows noninvasive, nondestructive measurement of corneal metabolism [4,5,7,[11][12][13]. Phosphatic metabolites, e.g., ATP, a 31p energy modulus, and intracorneal pH have been determined in eye-bank corneas [14].…”

“…It should be noted that inferential statistics were not applied due to the small sample size. MRS values of ATP, Pi and the phosphomonoesters, measured in mol% phosphorus, as well as the tissue energy modulus and pH (Table 5), were consistent with those values reported previously with MRS [7,11,14].…”

“…Such analyses on both experimental (MRS-examined) and control (non-MRS-examined) corneas were not significantly dif- Table 5 31P-MRS analysis performed on one cornea from each of four pairs of corneas studied (ATP adenosine triphosphate, Pi inorganic orthophosphate, PME phosphomonoesters, ATP/Pi ratio of ATP to Pi, PME/Pi ratio of PME to Pi, tissue energy modulus [7] ratio of high-energy phosphates to low-energy phosphates, pH intracorneal pH measured by MRS analysis [ Table 5), however, provides metabolic information of considerable diversity (metabolic levels, pH, high-energy phosphates) that is useful in assessing viability at the biochemical level. Moreover, the biochemical analysis is a more precise index of tissue function.…”

Potential Role for Glycerylphosphorylcholine in Cryopreservation

“…Similar findings were observed when previously GPC-incubated corneas were frozen at liquid nitrogen temperatures [5]. Moreover, it was discovered that accompanying the increase in intracorneal GPC, the metabolic integrity of the cornea as measured by the energy modulus [8,9] was maintained after cryogenic treatment [6].…”

Ex vivo phosphorus magnetic resonance spectroscopy on eye bank corneas and corneal metabolic health

“…The most sensitive indices are those associated with the high-energy phosphates such as ATP, because these are the first metabolites to be compromised when tissues are under stress [2,3,10]. Thus, the tissue energy modulus [7], the ratio of high-energy phosphates to low-energy phosphates, is a useful metabolic indicator of tissue health status. Healthy tissues have a modulus value in the range of 0.8 to 1.0.…”

“…Phosphorus-31 magnetic resonance spectroscopy (3~p_ MRS) allows noninvasive, nondestructive measurement of corneal metabolism [4,5,7,[11][12][13]. Phosphatic metabolites, e.g., ATP, a 31p energy modulus, and intracorneal pH have been determined in eye-bank corneas [14].…”

“…It should be noted that inferential statistics were not applied due to the small sample size. MRS values of ATP, Pi and the phosphomonoesters, measured in mol% phosphorus, as well as the tissue energy modulus and pH (Table 5), were consistent with those values reported previously with MRS [7,11,14].…”

“…Such analyses on both experimental (MRS-examined) and control (non-MRS-examined) corneas were not significantly dif- Table 5 31P-MRS analysis performed on one cornea from each of four pairs of corneas studied (ATP adenosine triphosphate, Pi inorganic orthophosphate, PME phosphomonoesters, ATP/Pi ratio of ATP to Pi, PME/Pi ratio of PME to Pi, tissue energy modulus [7] ratio of high-energy phosphates to low-energy phosphates, pH intracorneal pH measured by MRS analysis [ Table 5), however, provides metabolic information of considerable diversity (metabolic levels, pH, high-energy phosphates) that is useful in assessing viability at the biochemical level. Moreover, the biochemical analysis is a more precise index of tissue function.…”

Potential Role for Glycerylphosphorylcholine in Cryopreservation

“…Similar findings were observed when previously GPC-incubated corneas were frozen at liquid nitrogen temperatures [5]. Moreover, it was discovered that accompanying the increase in intracorneal GPC, the metabolic integrity of the cornea as measured by the energy modulus [8,9] was maintained after cryogenic treatment [6].…”

Ex vivo phosphorus magnetic resonance spectroscopy on eye bank corneas and corneal metabolic health

“…The most sensitive indices are those associated with the high-energy phosphates such as ATP, because these are the first metabolites to be compromised when tissues are under stress [2,3,10]. Thus, the tissue energy modulus [7], the ratio of high-energy phosphates to low-energy phosphates, is a useful metabolic indicator of tissue health status. Healthy tissues have a modulus value in the range of 0.8 to 1.0.…”

“…Phosphorus-31 magnetic resonance spectroscopy (3~p_ MRS) allows noninvasive, nondestructive measurement of corneal metabolism [4,5,7,[11][12][13]. Phosphatic metabolites, e.g., ATP, a 31p energy modulus, and intracorneal pH have been determined in eye-bank corneas [14].…”

“…It should be noted that inferential statistics were not applied due to the small sample size. MRS values of ATP, Pi and the phosphomonoesters, measured in mol% phosphorus, as well as the tissue energy modulus and pH (Table 5), were consistent with those values reported previously with MRS [7,11,14].…”

“…Such analyses on both experimental (MRS-examined) and control (non-MRS-examined) corneas were not significantly dif- Table 5 31P-MRS analysis performed on one cornea from each of four pairs of corneas studied (ATP adenosine triphosphate, Pi inorganic orthophosphate, PME phosphomonoesters, ATP/Pi ratio of ATP to Pi, PME/Pi ratio of PME to Pi, tissue energy modulus [7] ratio of high-energy phosphates to low-energy phosphates, pH intracorneal pH measured by MRS analysis [ Table 5), however, provides metabolic information of considerable diversity (metabolic levels, pH, high-energy phosphates) that is useful in assessing viability at the biochemical level. Moreover, the biochemical analysis is a more precise index of tissue function.…”