RU2535073C1 - Method of treating methemoglobinemia - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: perftoran is administered intravenously at 5-20 ml per 1 kg of body weight.

EFFECT: reducing side effects in treating methemoglobinemia by the property of perftoran to transform methemoglobin into oxyhemoglobin.

6 dwg, 2 tbl

Description

One of the most important functions of the blood is to transfer oxygen absorbed in the lungs: to organs and tissues, as well as to remove the carbon dioxide formed in them. Red blood cells play a key role in all of these processes. These cells contain hemoglobin, which can bind to oxygen and release it in the capillaries of tissues. The hemoglobin molecule contains four identical heme groups. A bivalent iron ion located in the center of each of the four gems plays a key role in hemoglobin activity. The O ₂ molecule reversibly binds to heme. By attaching oxygen, hemoglobin (Hb) is converted to oxyhemoglobin (HbO ₂ ). The valency of iron does not change. This process is called oxygenation, and the reverse process is called deoxygenation. Non-oxygenated hemoglobin is called deoxyhemoglobin.

The heme can undergo not only oxygenation, but also true oxidation. In this case, iron becomes divalent trivalent. Hemoglobin is converted to methemoglobin (MetHb). Oxidized heme is not able to carry oxygen to tissues. There is tissue hypoxia. At a MetHb level of 30-50% severe clinical manifestations are observed. Currently, due to the development of the pharmacological and chemical industry, methemoglobinemia of exogenous origin has become increasingly common. Increased methemoglobin formation in the human body is observed in workers in the production of aniline, nitrobenzene, nylon, lead and other chemical products, as well as in the use of a number of drugs (aspirin, nitroglycerin, pyramidone, etc.).

Methemoglobin is found in small quantities in human blood. But with some diseases and poisoning, its content increases. Methemoglobin formers include aniline and its derivatives, aminophenols and aminophenones, chlorates, dapsone, some local anesthetics (e.g. benzocaine), nitrites and nitrates, naphthalene, nitrobenzene and its derivatives, nitric oxide, phenazopyridine, primaquine and similar antimalarials and some sulfonamides.

Ascorbic acid is used to treat methemoglobinemia. Ascorbic acid is able to interact with toxicants in red blood cells. However, the speed of the process is low (S. A. Kutsenko. Fundamentals of Toxicology. // Biomedical Journal http://Medline.ru. Volume 4, p. 119. March, 2003).

It is believed that treatment with ascorbic acid is ineffective in acute methemoglobinemia. (Kambiz Soltaninejad, Leiws S. Nelson, Nastaran Khodakarim, Zohreh Dadvar, and Shahin Shadnia Unusual complication of aluminum phosphide poisoning: Development of hemolysis and methemoglobinemia and its successful treatment // Indian J Crit Care Med. 2011 Apr-Jun; 15 (2 ): 117-119). In addition, the intake of ascorbic acid in doses exceeding physiological can shorten the prothrombin time, destroy vitamin B12, promote the formation of oxalate stones in the urinary tract, have a depressing effect on the insular apparatus of the pancreas, stimulate the formation of corticosteroid hormones, which under certain conditions can lead to damage to the glomeruli of the kidneys and the development of arterial hypertension. (EGKazanets Federal Scientific and Clinical Center for Pediatric Hematology, Oncology, Immunology, Moscow. Methemoglobinemia // Children's Hospital. 2009. No. 1. P.38-42).

A known method of treating methemoglobinemia by intravenous administration of methylene blue at a dose of 1-2 mg / kg This method is based on the reduction of oxidized ferric to ferrous.

The disadvantage of this method is that methylene blue itself is an oxidizing agent, especially in large doses (usually more than 4 mg / kg), methylene blue can act predominantly as an oxidizing agent. In some patients, after the introduction of methylene blue, an initial decrease in the level of methemoglobin occurred, and then later a secondary increase in the level of methemoglobin occurred. In this case, methylene blue can cause the development of hemolytic anemia and methemoglobinemia. Clinical complications have been reported with the intravenous administration of methylene blue in patients with glucose-6-phosphate dehydrogenase deficiency, as well as in young children. Consequently, methylene blue therapy can sometimes be completely ineffective for such patients.

(Greenberg, Michael I. MD, MPH Methylene Blue: Fast-Acting Antidote for Methemoglobinemia // Emergency Medicine News. September 2001 - Volume 23 - Issue 9 - p. 26 Toxicology Rounds, doi: 10.1097 / 01. EEM. 0000292322.94148.37. )

The objective of the invention is a method for the treatment of methemoglobinemia with fewer side effects.

The problem is solved by the method of treatment of methemoglobinemia, which consists in the fact that perfluorane (PF) 5-20 ml per 1 kg of body weight is administered intravenously.

The method is based on the property of PF that we first discovered to convert methemoglobin to oxyhemoglobin.

It is known that "Perftoran" (perfluorodecalin emulsion) (L. A. Bogdanova, E. I. Maevsky, R. Ya. Senina, S. Yu. Pushkin, O. G. Aksenova, G. R. Ivanitsky. A brief review of the clinical the use of perfluorane // Biomedical journal http://Medline.ru. February, 2001 Volume 2. ST.5. Pages 30-36) - blood substitute with gas transport function, with a multifunctional effect. Therefore, it can be administered to the patient in the blood without fear of toxic effects. PF is administered intravenously at a rate of 1 to 30 ml per 1 kg of weight (or more in acute massive blood loss). It is possible to re-administer the drug in the same dose with an interval of several hours (with massive blood loss) up to 3 days.

For the treatment of acute blood loss, PF is administered in a higher concentration. (L.A. Bogdanova, E.I. Maevsky, R.Ya.Senina, S.Yu. Pushkin, O.G. Aksenova, G.R. Ivanitsky. A brief review of the clinical use of perfluorane // Biomedical Journal http: // Medline.ru, February 2001, Volume 2, Article 5, Pages 30-36).

The following examples illustrate the method of the invention.

1. In vitro experiments

Blood was taken into microvets with EDTA. For the oxidation of hemoglobin, a solution of sodium nitrite NaNO _{2 was used} . For this, NaNO _{2 was} prepared in distilled water at a concentration of C = 0.13 g / ml. 10 μl of this solution, C = 100 mM, was added to a microveta with blood (200 μl) (Fig. 1). The blood from scarlet turned dark brown. Then the blood was washed 3 times from a NaNO ₂ solution and centrifuged (2500 rpm, 5 min). Each time, 100 μl of saline was removed. Then formed a control suspension and a suspension with PF. Control suspension: 100 μl of saline was added to 100 μl of red blood cells. Suspension with PF - 100 μl of PF was added to 100 μl of red blood cells. Both suspensions were still brown, which qualitatively indicated the presence of a large amount of MetHb.

Figure 1 shows the conversion of oxyhemoglobin to methemoglobin and the reduction of methemoglobin to oxyhemoglobin after the addition of perfluorane.

After 6-24 hours, the suspension with PF became scarlet, which qualitatively testified to the conversion of MetHb to HbO ₂ .

For the quantitative determination of the concentrations of hemoglobin derivatives, the standard spectrophotometric method was used (Fig. 2). Deoxyhemoglobin has a maximum in the absorption spectrum at a wavelength of λ = 555 nm. Oxyhemoglobin - two maxima at λ = 542 nm and λ = 577 nm (Fig. 2). The methemoglobin spectrum has four absorption bands, of which the most distinct band is located at λ = 630 nm.

Figure 2 shows the absorption spectra: 1 - deoxyhemoglobin; 2 - oxyhemoglobin; 3 - methemoglobin (Blumenfeld L.A. Hemoglobin // Articles of the Sorov Educational Journal. 1998.)

Figure 3 shows photographs of solutions obtained by adding 30 μl of blood to 3 ml of distilled water.

Fig. 4. The corresponding spectra are presented 1 hour after the administration of PF (a), after 24 hours (b)

To calculate the concentrations of hemoglobin derivatives, the following formulas were used (Stus L.N., Rozanova E.D. Oscillation of hemoglobin forms in the process of blood storage. // Biophysics, 1992, 37. P.387-388):

$$\begin{array}{l}C(\mathrm{<figure-callout\; id="2"\; label="H\; b\; O"\; filenames="00000003.png,00000007.png"\; state="\{\{state\}\}">H\; </figure-callout>}b{O}_{}{}_2=0.17D_{577}-0.13D_{569}-0.015D_{500}\\ C(Hb)=-0.16D_{577}+0.25D_{569}-0.033D_{500}\text{(one)}\\ C(MetHmb)=-0.02D_{577}-0.04D_{569}+0.13{\mathrm{<figure-callout\; id="500"\; label="D"\; filenames="00000003.png,00000005.png"\; state="\{\{state\}\}">D</figure-callout>}}_{500}\end{array}$$

where D ₅₇₇ , D ₅₆₉ , D ₅₀₀ are the values of optical density at wavelengths of 577, 569, 500 nm.

Figure 5 shows histograms of the concentrations of hemoglobin derivatives in the blood in the control group (K) exposed to NaNO ₂ , exposed to NaNO ₂ and subsequent PF administration.

Table 1 for comparison shows the concentrations of methemoglobin and oxyhemoglobin in the control suspension, in suspension after exposure to NaNO ₂ and after exposure to NaNO ₂ and the subsequent introduction of PF.

Table 1 Change in the concentrations of methemoglobin, oxyhemoglobin and deoxyhemoglobin in an in vitro experiment Methb% HbO ₂ % Hb in control solution 2.5 ± 0.5 60 ± 3 37.5 ± 0.5 after exposure to NaNO ₂ 82 ± 5 4 ± 1 14 ± 3 after exposure to NaNO ₂ and subsequent exposure to PF 17 ± 3 48 ± 2 35 ± 8

Thus, perfluorane effectively converts methemoglobin to oxyhemoglobin.

Example 2. Experiments on laboratory animals

The experiments were performed on non-linear male rats weighing 470 ± 50 g. Methemoglobinemia was artificially induced in 10 rats by introducing a 2% solution of phenylhydrazine hydrochloride at a rate of 150 mg per 1 kg of animal weight (table 2).

In the first group of 5 animals (untreated animals), four rats died in 48 hours, in the fifth rat, after 48 hours, the MetHb level remained the same, it died on the 5th day.

In the second group of 5 animals, PF was administered at a concentration of 20 ml per 1 kg of weight. After 24 hours, the level of methemoglobin decreased to 28-45%. Then they repeated the therapy. For this, PF was again introduced in the same amount. As a result, after 48 hours from the start of treatment with PF, the MetHb level decreased to 5-17% (table 2).

As a result, all five animals of the test group survived during the next 25 days of observation.

table 2 Changes in the concentrations of methemoglobin and oxyhemoglobin in rats (K) in an in vivo experiment. L - fatal outcome Methb% Originally After 24 hours After 48 hours In the control group K1 62 63 L K2 55 54 L K3 65 64 L K4 66 68 L K5 52 51 52 In the group with PF therapy K6 60 thirty 12 K7 62 41 fifteen K8 53 28 5 K9 67 45 17 K10 59 31 13

Figure 6 shows the time dependences of the average level of methemoglobin in rats in the control group (1) and in the group with PF therapy (2). L - fatal outcome in four rats.

Thus, the above data indicate the achievement of the objectives of the invention of the treatment of methemoglobinemia.

It should be noted that in this case PF also has other already known useful properties, which means its safe use for the transformation of methemoglobin into oxyhemoglobin.

Claims (1)

A method of treating methemoglobinemia, which consists in the fact that perftoran is administered intravenously at the rate of 5-20 ml per 1 kg of body weight.

Images