Alkyl glycerols

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General structural formula of an alkyl glycerol.

From a chemical point of view, alkyl glycerols belong to the group of ether lipids . The basic structure of these substances is glycerine . In contrast to glycerine, one of the hydroxyl groups forms an ether with a hydrocarbon chain . The three most common alkyl glycerols are chimyl alcohol , batyl alcohol, and selachyl alcohol .

Historical

The alkyl glycerols were discovered in 1922 by the Japanese scientists Tsujimoto and Toyama and were first synthesized in 1930 by the Nobel Prize winner Sir Robert Robertson.

In 1962, the natural occurrence of alkyl glycerols in mammals was demonstrated by Bo Hallgren and Sven Larsson using chromatography and mass spectrometry .

Astrid Brohult, head of the radiation therapy department at the renowned Karolinska Institute in Solna near Stockholm , together with her husband Sven Brohult researched the importance of alkylglycerols for the immune system and carried out several studies (1954–1986).

Occurrence

Alkyl glycerols are natural substances. The highest concentration is found in the liver of cold-water sharks , such as the greenland shark ( Somniosus mikrocephalus ). Alkylglycerols are found in blood-forming organs such as the liver, spleen and bone marrow . In addition, relatively high concentrations are found in human breast milk.

properties

Due to their chemical structure, alkyl glycerols are lipophilic compounds. Alkyl glycerols are colorless and odorless. Due to the lipophilic structure, they are able to penetrate membranes and improve their fluidity.

  • Selachyl alcohol

  • Chimyl alcohol

  • Batyl alcohol

Biological function

Alkyl glycerols modulate the immune system . The unspecific defense is strengthened by the formation of more immune competent cells. In addition, the cell activity is increased. The immune function of the bone marrow is stimulated, but there is no overstimulation.

Alkyl glycerols promote the growth of the beneficial intestinal bacteria Lactobacillus acidophilus and inhibit the growth of harmful fungi and bacteria. The antibiotic effect is comparable to that of nitrofurantoin .

In animal experiments, alkyl glycerols also inhibit angiogenesis in tumors and they reduce the side effects of radiation therapy. The radiation-induced reduction in white blood cells and platelets is reduced. Radiation-induced lesions of the skin and mucous membranes are reduced by alkyl glycerols and wound healing is promoted.

A cytotoxic effect on tumor cells could be demonstrated in cell cultures. This effect has been confirmed by studies on rats and guinea pigs. In addition, several animal studies have shown that alkyl glycerols can inhibit the spread and growth of tumors.

A study at Radiumhemmet, the radiation therapy department at the Karolinska Institute in Stockholm, showed a positive effect on the survival rate of patients with cervical cancer . 4,000 patients took part in this study.

To date, there is no approved drug based on alkyl glycerols.

application areas

Nutritional supplement

Fish liver oil was mainly used by Nordic ethnic groups, such as the Eskimos and Scandinavian fishermen, as a dietary supplement because of the high content of various vitamins.

In 1922, Tsujimoto and Toyama found alkyl glycerols in shark liver oil, and in 1930 Sir Robert Robinson first synthesized such compounds. In natural sources they always occur esterified with fatty acids. In the 1950s to 1960s, extensive research was carried out by Astrid Brohult at the Karolinska Institute in Stockholm on the effect of alkyl glycerols in reducing the side effects of cancer therapies.

Alkylglycerols are now marketed as dietary supplements for infection prophylaxis or for existing infections. Other possible areas of application are in the field of complementary oncology, where the aim is, for example, to reduce the side effects of cancer therapy.

The anti-cancer effects are primarily attributed to the activation of macrophages and the increase in the production of cytokines such as interleukin IL-12 and IFN-gamma . Although further randomized clinical trials are required to confirm the properties of these molecules and to rule out possible side effects, the prospects as nutritional supplements in diseases are promising.

Individual evidence

  1. ↑ a b FL Snyder (ed.); HK Mangold: In Ether Lipids: Chemistry and Biology . Academic Press, New York 1972, pp. 157-176.
  2. ^ A b GG Davies, IM Heilbron, WM Owens: the unsaponifiable matter from the oils of elasmobranch fish. The synthesis of a-glycerol ethers and its bearing of the structure of batyl, selachyl and chimyl alcohols. In: J. Chem. Soc. 2542, 1930.
  3. ↑ B. Hallgren, S. Larsson: The glycerol ethers in man and cow. In: Lipid Res. 3, 1962, pp. 39-43.
  4. ^ A b A. Brohult, J. Holmberg: Alkoxyglycerols in the treatment of Leucopenia caused by irradiation. In: Nature. 174, 1954, p. 1102.
  5. ^ A b A. Brohult, J. Brohult, S. Brohult, I. Joelsson: Effect of alkylglycerols on the frequency of injuries followin radiation therapy for carcinoma of the uterine cervix. In: Acta Obstet Gynecol Scasnd. 56 (4), 1977, pp. 441-448.
  6. ^ A b A. Brohult, J. Brohult, S. Brohult: Regression of tumor growth after administration of alkoxyglycerols. In: Acta Obstet Gynecol Scand. 57, 1978, pp. 79-83.
  7. ^ A b A. Brohult, J. Brohult, S. Brohult, I. Joelsson: Reduced mortality in cancer patients after administration of alkoxyglycerols. In: Acta Obstet Gynecol Scand. 65, 1986, pp. 779-785.
  8. ↑ B. Hallgren, S. Larsson: The glyceryl ethers in the liver oils of elasmobranch fish. In: Journal of Lipid Research. Vol. 3, No. 1, 1962, pp. 31-38.
  9. ↑ B. Hallgren, S. Larsson: The glycerol ethers in man and cow. In: Lipid Res. 3, 1962, pp. 39-43.
  10. ^ H. Blomberg: Influence of Ecomer / Alkymer alkylglycerols on different parameters in blood of healthy subjects . (Statistical evaluation of Juri Reznikov's study in Moscow, ref no 33.)
  11. ↑ MP Haynes, HR Buckley, ML Higgins, RA Pieringer: Synergism between the antifungal agents amphotericin B and alkylglycerol ethers Antimicrob . In: Agents Chemotherapy. 38 (7), July 1994, pp. 1523-1529.
  12. ↑ E. Skopinska-Rozewska, M. Krotkiewski, E. Sommer, E. Rogala, M. Filewska, B. Bialas-Chromiec, K. Pastewka, H. Skurzak: Inhibitory effect of shark liver oil on cutaneous angiogenesis induced in Balb / c mice by syngeneic sarcoma L-1, human urinary bladder and human kidney tumor cells. In: Oncol Rep. 6 (6), 1999, pp. 1341-1344.
  13. ↑ R. Firshein, J. Brohult, R. Rothstein Ruby: Effects of Alkylglycerols on Cellular Growth and Sensitivity to Chemotherapeutic Agents in tumor Cultures . Thirty-fifth Annual Meeting of the American Society of Clinical Oncology. May 15-18 1999. Atlanta, Georgia.
  14. ↑ M. Krotkiewski et al: Cytostatic and cytotoxic effects of alkylglycerols (Ecomer). In: Med Sci Monit. 9 (11), 2003, pp. 131-135. PMID 14586289 .
  15. ↑ B. Boeryd, T. Nilsson, L. Lindholm, S. Lange, B. Hallgren, G. Ställberg: Stimulation of immune reactivity by methoxysubstituted glycerol ethers incorporated into feed. In: European Journal of Immunology. Vol. 8, 1978, pp. 678-680.
  16. ^ M. Petersson, I. Näslund: Alkylglycerols (Ecomer / Alkymer) to mice with tumor burden. Microbiology and Tumor Biology Center (MTC), Karolinska Institute, Stockholm Sweden.
  17. ^ Lee McDowell: Vitamin History, the Early Years . First Edition Design Pub., 2013, ISBN 978-1-62287-252-7 ( limited preview in Google Book Search).
  18. ^ Health Risks Related to High Intake of Preformed Retinol (vitamin A) in the Nordic Countries . Nordic Council of Ministers, 2003, ISBN 92-893-0860-5 , p. 86 ( limited preview in Google Book search).
  19. ↑ a b Tommaso Iannitti, Beniamino Palmieri: An Update on the Therapeutic Role of Alkylglycerols. In: Marine Drugs. 8, 2010, p. 2267, doi: 10.3390 / md8082267 .
  20. ↑ Joseph E. Pizzorno, Michael T. Murray: Textbook of Natural Medicine . Elsevier Health Sciences, 2013, ISBN 978-1-4377-2333-5 , pp. 563 ( limited preview in Google Book search).
  21. ↑ Karsten Münstedt: Advice on unconventional cancer therapies . ecomed-Storck GmbH, 2005, ISBN 3-609-16329-1 , p. 264 ( limited preview in Google Book search).

literature

  • PT Pugliese, K. Jordan, H. Cederberg, J. Brohult: Some biological actions of Alkylglycerols from Shark Liver Oil. In: The Journal of alternative and complementary medicine. Volume 4, Number 1, 1998, pp. 87-99. PMID 9553838 .