Medical Hypotheses 84 (2015) 408–412
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Medical Hypotheses journal homepage: www.elsevier.com/locate/mehy
Hypothesis of demodicidosis rosacea flushing etiopathogenesis q Mary Ann Robledo a,⇑, Mariana Orduz b a b
Calle 33# 42B-06 C.C Sandiego Torre sur 1122, Medellin, Colombia Universidad CES, Medellin, Colombia
a r t i c l e
i n f o
Article history: Received 21 October 2014 Accepted 22 January 2015
a b s t r a c t Most of the patients with erythematotelangiectatic rosacea are characterized by flushing, oedema and telangiectasia. The etiopathogenesis of the flushing in rosacea patients is unknown. Clinically the flushing in rosacea is similar to the ‘‘Asian flushing syndrome’’. Most Asians have an overactive alcohol dehydrogenase (ADH) that tends to break down alcohol into acetaldehyde faster. People with ‘‘Asians flushing syndrome’’ have a genetic disorder with the Aldehyde Dehydrogenase 2⁄2 (ALDH2⁄2) allele. This is the reason why they do not metabolize very well the acetaldehyde that comes from the alcohol, which means that acetaldehyde takes much longer to clear from their blood. ALDH2 enzyme is primarily responsible for oxidation of acetaldehyde derived from ethanol metabolism, as well as oxidation of various other endogenous and exogenous aldehydes. Acetaldehyde produces the vasodilatation in the ‘‘Asian flushing syndrome’’. The antibodies against the GroEl chaperonin protein, a 62-kDa heat shock protein were found in the Bacillus oleronius isolated from Demodex mites, in rosacea patients. The GroEl chaperonin protein is a protein that plays a key role in normal folding of ALDH2. If the GroEl chaperonin antibodies found in patients with rosacea, cross react with the human GroEl chaperonin protein, they will not fold normally the ALDH2, and then the enzyme will not metabolize the acetaldehyde. Many of the patients with rosacea have a concomitant infection with Helicobacter pylori in their stomach. The H. pylori produces high amounts of acetaldehyde, which comes from their metabolism of ethanol or carbohydrates. As a result, high amounts of acetaldehyde will circulate for longer time in the blood, until the liver CYP2E1(p450) enzyme system finally metabilizes the acetaldehyde, during that period of time the patients will experience a flushing as well as the people with the ‘‘Asian flushing syndrome’’ suffer when they drink ethanol. To prove the hypothesis it is necessary to find the cross reaction between the GroEl chaperonin antibodies against the B. oleronius and human GroEl chaperonin. Four groups of patients will be studied with or without the GroEl chaperonin antibodies, and H. Pylori. The production of acetaldehyde will be tested by the ethanol-derived microbial production method. If the hypothesis proves to be true, the treatment of Demodex mites and the H. pylori could improve the flushing in the rosacea patients and it will prevent the angiogenesis (telangiectasia), and the association of the gastric injury and carcinogenesis in those patients. Ó 2015 Elsevier Ltd. All rights reserved.
Introduction/background According to the article published by O’Reilly et al.: ‘‘Rosacea is a chronic inflammatory condition that affects the skin of the face and the eyes. Erythematotelangiectatic rosacea is characterized by flushing, oedema and telangiectasia. Patients with rosacea demonstrate elevated densities of Demodex mites in their skin compared with controls. A bacterium, Bacillus oleronius isolated from Demodex mites, from a patient with papulopustular rosacea has been demonstrated to produce antigenic proteins that may play a role in papulopustular and ocular rosacea. Eighty per cent (21/ q
Not sources of support.
⇑ Corresponding author. Tel.: + 574 2629678. E-mail address: [email protected] (M.A. Robledo). http://dx.doi.org/10.1016/j.mehy.2015.01.036 0306-9877/Ó 2015 Elsevier Ltd. All rights reserved.
26) of patients with erythematotelangiectatic rosacea showed serum reactivity to the 62- and 83-kDa proteins of B. oleronius, compared with 40% (9/22) of controls (P = 0Æ004). The 62-kDa protein was characterized by liquid chromatography-mass spectrometry (LC-MS) analysis and showed homology to GroEL chaperonin which provokes a strong immune response in mammals’’ [1]. ‘‘How well the body metabolizes or a break down alcohol is dependent on two enzymes: alcohol dehydrogenase (ADH) which converts alcohol into acetaldehyde and acetaldehyde dehydrogenase 2 (ALDH2) which breaks down acetaldehyde into harmless substances. Because 80% of Asians have an overactive alcohol dehydrogenase (ADH), they tend to break down alcohol into acetaldehyde faster, up to 100 times faster. As alcohol is broken down faster, there may be little to no alcohol ‘‘buzz’’’’ [2].
M.A. Robledo, M. Orduz / Medical Hypotheses 84 (2015) 408–412
‘‘The flushing syndrome described in oriental people, genetically the ADH2⁄2 allele encodes the b2 subunit; isozymes containing b2 sub-units oxidize alcohol faster in vitro than the b1b1 isozyme encoded by ADH2⁄1. Thus, the simplest explanation for this data is that individuals with b2 isozyme have a higher rate of ethanol oxidation, which is a deterrent to alcohol abuse and dependence in some individuals. The Atayal with alcohol use disorders also had a lower frequency of ALDH2⁄2 than the controls; this allele is known to be responsible for the alcohol-flushing reaction among Asians, and thereby deters drinking’’ [3]. ‘‘Many mitochondrial proteins are synthesized in the cytosol as precursor proteins and subsequently interact with one or more chaperonin proteins. Chaperonin can use the energy of ATP hydrolysis to keep the precursor proteins in an unfolded state so that they can be imported into mitochondria. Many matrix proteins are fabricated as precursors that have a matrix-targeting sequence at their N-terminus. The enzyme ALDH2 also contains 17-amino acids of matrix-targeting sequence and this peptide signal contains all the information required for translocation from cytosol to the mitochondrial matrix. After transporting, the sequence is cleaved by matrix protease. Imported proteins like ALDH2 are then folded correctly with the assistance of matrix proteins designated heat shock protein (hsp), hsp 60 and hsp10. These chaperone proteins are essential for protein folding and multi subunit protein assembly in the mitochondria. In addition, GroES (in particular) and GroEL, the E. coli homolog of hsp10 and hsp60 mitochondrial chaperone proteins, respectively, play a key role in normal folding of recombinant ALDH2’’ [4,5]. Patients with rosacea have a common Helicobacter pylori bacteria infection in their stomach. ‘‘The H. pylori prevalence in rosacea patients was about 88%, compared to 65% in the non-ulcer dyspepsia (NUD) controls. A noticeable number of rosacea patients showed chronic active gastritis predominantly in antrum but also in the corpus, while those with non-ulcer dyspepsia (NUD) showed only mild gastritis confined to the antrum only’’ [6]. ‘‘The H. pylori shows alcohol dehydrogenase activity, which in the presence of ethanol leads to in vitro production of acetaldehyde, a toxic and highly reactive substance. The H. pylori produced acetaldehyde from exogenous or endogenous ethanol may be one of the pathogenesis mechanism behind gastric mucosal injury associated with this organism’’ [7–9].
The hypothesis/theory As it is explain in the Table 1: a number of articles confirm the hight association in the etiopathogenesis of the rosacea and Demodex mites infestation. [1,10–14]. Lacey and cols. found the B. oleronius as endosymbiotic bacteria in the gut of the Demodex mites [15]. In human’s skin, this bacillus may occur in the endospore form, which enters the digestive tract of Demodex mites when they consume oil and epithelial cells [16]. Eighty percent of patients with erythematotelangiectatic rosacea showed serum reactivity to the 62- and 83-kDa proteins of B. oleronius. The 62-kDa protein from the B. oleronius was characterized by liquid chromatography– mass spectrometry (LC–MS) analysis and showed homology to GroEL protein, a heat shock protein, that is necessary to fold the Aldehyde Dehydratase enzyme 2 (ALDH 2), [1,4]. The antibodies against the GroEl chaperonin protein from the bacteria could make a cross reaction against the human GroEl chaperonin protein. Additionally, ALDH 2 is not able to assemble in the mitochondria. The ethanol that comes from the oral intake or from carbohydrate metabolism from enteric bacteria and H. pylori will be metabolized by the alcohol dehydrogenize enzyme (ADH) to acetaldehyde [7–9,17]. The ADH and the ALDH2 enzymes are a NAD+ – NADH+H dependent. If the ALDH 2 enzyme could not fold because
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the GroEl chaperonin is blocked by cross reactive antibodies against the B. oleronius 62-kDa protein. Then, high concentrations of acetaldehyde could circulate in the blood system for a longer period of time until the liver CYP2E1(p450) enzyme system finally metabolizes the acetaldehyde. The liver metabolized actions take more time that the ALDH2 enzyme normally take. The CYP2E1 require NADPH to produce the final products [18]. The high acetaldehyde concentrations in the blood produce vasodilatation and redness ‘‘flushing’’. The flushing appears especially in the face such as the oriental people which suffer the ‘‘Asian flushing syndrome’’ after the ethanol intake (2,3). Chronically the acetaldehyde could also produce the angiogenesis and the telangiectasia by the expression of Vascular Endothelial Growth Factor (VEGF) that was experimentally demonstrated by the chick embryo chorioallantoic membrane model (CAM) [19].
Evaluation of the hypothesis To search the patients it will be necessary to look for the clinical features of erythematotelangiectatic rosacea, which are characterized by flushing, oedema and telangiectasia. To find the GroEl chaperonin antibodies in the rosacea patients it is important to look for the Demodex mites, by using standardized skin-surface biopsy in them [13]. Skin-surface biopsy is also needed to rule out the Demodex in the negative controls individuals. An optimized 13C urea breath test is required for the diagnosis of H. pylori in order to find the positive controls, and to exclude the infection of H. pylori in the negative controls [20]. Endoscopic procedures will be necessary only if the 13C urea breath test is questioned. Patients with the ‘‘Asian flushing syndrome’’ with the genetic disorder with the Aldehyde Dehydrogenase 2⁄2 (ALDH2⁄2) allele must be disqualified of the study. It is indispensable to confirm that the antibodies detected against the GroEl chaperonin, 62 KDa hsp, from B. oleronius make a cross reaction against the human GroEl chaperonin protein, using ELISA or western blot assay with both proteins, and using the adequate negative and positive controls [1]. The four following groups of patients will be studied: (1) Patients with demodicidosis eritematotelangiectasia rosacea with positive antibodies against GroEl chaperonin and positive to H. pylori gastric infection (++). (2) Patients with demodicidosis eritematotelangiectasia rosacea with positive antibodies against GroEl chaperonin and negative to H. pylori gastric infection (+ ). (3) Patients with negative antibodies against GroEl chaperonin and positive to H. pylori gastric infection ( +). (4) Patients or a person with negative antibodies against GroEl chaperonin human protein and negative to H. pylori gastric infection ( ). Following the method described by Väkeäinen, and cols. in: ‘‘Ethanol-derived microbial production of carcinogenic acetaldehyde in achlorhydric atrophic gastritis: for the in vivo study, glucose or ethanol was infused via a nasogastric tube to the stomach of seven achlorhydric atrophic gastritis patients and five healthy controls. Gastric juice samples for ethanol and acetaldehyde determinations and microbial analysis were obtained at 30 and 60 min after the infusions. For the in vitro study, gastric juice samples from 14 atrophic gastritis patients and 16 controls were obtained during gastroscopy, where after the samples were incubated for 2 h with 1% ethanol at 37 degrees C and acetaldehyde was determined’’ [21]. The study of acetaldehyde could be performed by the same methods used in the article: ‘‘Characteristics
410 Table 1 Etiophatogenesis pat way of rosacea flushing.
M.A. Robledo, M. Orduz / Medical Hypotheses 84 (2015) 408–412
M.A. Robledo, M. Orduz / Medical Hypotheses 84 (2015) 408–412
of H. pylori alcohol dehydrogenase: to study the acetaldehyde produced by cytosol during incubation with ethanol could be measured by spectrophotometrical determination of the aldehyde dehydrogenase activities and with head space gas chromatography’’ [7–9]. Concomitantly, clinical observations of flushing symptoms during the standardized ethanol intake test must be evaluated in the four groups of patients. We will demonstrate that the hypothesis is true if the first group (++), has higher levels of acetaldehyde that last longer in time when they have the flushing, using the standardized ethanol intake amount test, in comparison of the other groups and we expect to have negative de ( ) control group. Patients of the second group (+ ): if they have positive levels of acetaldehyde they also help to prove the hypothesis, but, negative levels means that the association with H. pylori will be necessary to have the flushing. Patients in the third group ( +), will be positive because the H. pylori produces acetaldehyde as it has been proved all ready [7–9]. Consequences of the hypothesis and discussion If the antibodies cross react against the human GroEl chaperonin and the acetaldehyde concentrations are higher in the first group of patients and negative in the fourth group (negative control), we can confirm that the association of Demodex mites with the B. oleronius endosymbiotic bacteria antibodies and the H. pylori gastric infection play a pathogenic role in the rosacea flushing and telangiectasia angiogenesis. It is already proofed that high acetaldehyde concentration is the cause of the ‘‘Asian flushing syndrome’’; it is clinically identical to the rosacea flushing. The rosacea telangiectasia angiogenesis could be explained by the chronically acetaldehyde circulation that produce the VEGF, that was experimentally demonstrated by the CAM [19]. Salvado et al, found that the Cathelicidin LL-37 induces angiogenesis via PGE2– EP3 signaling in endothelial cells that also increase the angiogenesis in rosacea patients. The frequent association, of the Demodex mite and the H. pylori in rosacea patients has been reported [6]. The connection between these two agents may explain the increase of the flushing and the angiogenesis in the face of the rosacea patients and also the internal gastric injury. Cribier, recently published the article ‘‘Physiopathology of rosacea’’, and he quoted: ‘‘For a long time rosacea was thought to be mainly a vascular disorder. In the past ten years many other concepts have emerged, such as the neurovascular aspects and involvement of innate immunity. There is obviously a genetic part in rosacea, as it is much more common in people with fair skin, blue eyes and Celtic ascendance. The same people are submitted to continental weather, with major temperature seasonal variations. Erythema and telangiectasia result from dilated superficial capillaries that have bizarre shapes, and induce constant edema of the dermis. This might be a favoring factor for Demodex colonization, which plays a major role in rosacea. Inflammation is always present, even in erythematotelangiectatic subtypes. It involves innate immunity, in response to environmental factors, like Demodex and its own biotope, resulting in overproduction of LL37, a proinflammatory peptide able to induce skin inflammation in an animal model, through activation of inflammatory cells. Tool like receptors are involved in the activation of innate immunity. Demodex is the cause of granulomas seen in papulopustular rosacea, but it is also always present in the erythematotelangiectatic subtype. Colonization by Demodex is nevertheless not decreased with conventional treatments of rosacea, like tetracyclins and metronidazole. This might be due to induction of inflammation by bacteria hosted by Demodex, like B. oleronius, and dozens of bacteria that are being investigated. Finally, rhinophyma is linked to both vascular
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changes and activation of fibrosis, involving TGF beta’’ [22]. We are agreeing with Cribier, that most of the immunological reactions in rosacea are due by the Demodex and their endosybiotic bacteria. If our hypothesis is prove to be true, the antibodies against the GroEl chaperonin and the acetaldehyde produced by H. pylori in a concomitant gastric infections are responsible for the symptoms of ‘‘flushing’’ and the erythema and telangiectasia in rosacea patients. The flushing symptom is not explained by the actinic damage in those patients. It is true that many rosacea patients could have, off course, concomitant actinic damage, but not all of them have strong sun damage, because we have patient’s photo type IV and V with rosacea, in our experience here in the tropic area of Colombia, with little actinic damage and with demodicidosis rosacea flushing and erythema. Akilov and Mumcuoglu has been established, ‘‘that there is a positive correlation between high density of Demodex mites and the presence of, HLA Cw2 and Cw4,’’ [23]. This indicates that there is a genetically susceptibility to acquire the Demodex mites infestation. This etiopathogenesis rosacea flushing pathway hypothesis could complement the knowledge of the pathogenic pathways of gastric injury. Two hypotheses are well described and complement each other. One is with the acetaldehyde that inhibits gastric mucosal regeneration and forms stable adducts with mucosal proteins [24]. ‘‘Formation of acetaldehyde adducts occurred relatively rapidly within 30 min and even at low acetaldehyde levels (5 lmol/L). Stable adducts represented 77% ± 5% (mean ± SEM) of the total adducts formed. In the presence of ethanol, acetaldehyde production and adduct formation took place in a concentration and time- dependent manner. 4-Methylpyrazole and sodium azide inhibited acetaldehyde production to 7% ± 1% of control and decreased the amount of acetaldehyde adducts to 55% ± 8%. Enhanced acetaldehyde formation (to 420% ± 50%) was clearly reflected in increased adduct formation (550% ± 110%). In conclusion, both exogenous and endogenous acetaldehyde binds to gastric mucosal proteins in vitro. Gastric mucosal acetaldehyde production and the consequent adduct formation could be a pathogenetic factor behind ethanol-associated gastric injury’’ [25]. And the other one is the Correa epidemiological studies in the gastric cancer and MALT lymphoma associated with the H. pylori gastric infection [26]. In the paper ‘‘The gastric precancerous cascade’’ explains Correa´s cascade, based in: ‘‘The presence of virulent factors in the infecting H. pylori strain is a known determinant factor of the outcome of the infection. Infection with cag-positive vacA s1m1 strains is associated with precancerous lesions and the development of gastric cancer; while persistent later renamed non-atrophic gastritis (NAG), associated to cag-negative vacA s2m2 does not increase the risk of cancer’’ [27]. Our hypothesis could explain the flushing and the angiogenesis in erythematotelangiectatic rosacea patients. The angiogenesis could play an important role in the pathogenesis of cancer and in the cancer progression. Gu et al. quoted: ‘‘Growth and expansion of tumor masses are dependent strictly on the sustained formation of new blood vessels, a process termed angiogenesis. We recently reported that physiologically relevant levels of ethanol induced VEGF expression and angiogenesis both in models of cell culture and in the chick chorioallantoic membrane (CAM). Therefore, we hypothesized that ethanol-induced angiogenesis and VEGF expression represent an important mechanism of cancer progression associated with alcoholic beverage consumption’’ [19]. The Acetaldehyde has been also well studied by the Scandinavian group, and is implicated in the gastric injury and carcinogenesis [7–9,17,21,24,25]. The H. pylori gastric infection and Demodex mite’s skin infestation are both the most common human infection and infestation, both are chronic and they can be acquired since childhood
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M.A. Robledo, M. Orduz / Medical Hypotheses 84 (2015) 408–412
[12,28]. These microorganisms have been described as human normal microbiota and for a long time, they were considered nonpathogenic, but the knowledge has changed, and both are playing an important role in the pathogenesis of rosacea and in the gastric diseases [1,9–14,21,24,25]. If we make an early diagnosis of both agents; and if we treat them efficiently and prevent the infection and infestation of both microorganisms; we can possibly control the rosacea, and also will prevent gastric dysplasia, gastric cancer and MALT lymphoma [29]. Szlachcic et al. said: ‘‘The eradication of H. pylori leads to a dramatic improvement of symptoms of rosacea and reduction in related gastrointestinal symptoms, gastritis, hypergastrinemia and gastric acid secretion’’ [30]. We consider that it is necessary to treat the Demodex mites with topical acaricidal like, crotamiton [31], ivermectin [32], permetrin [33,34], and antibiotic as tetracycline [35]. It is very important to search in the family members the asymptomatic contacts in order to prevent the reinfestation of the Demodex mites. This will be controlled by using standardized skin-surface biopsy and the H. pylori gastric bacteria performing the 13C urea breath test. It will be necessary to advise these patients to decrease the alcohol and high carbohydrate intake while the H. pylori and Demodex are present in them. As in many other infectious diseases, the line between health and disease is due by the genetic host susceptibility, the virulence of the microorganism, and the way that the immune system responds. Conflict of interest The author has no potential conflict of interest. This work has not been financially supported. Acknowledgments We thank our father and grandfather Dr. Mario Robledo – Villegas (1927–2010) , pathologist and dermatopathologist, who started with us the studies and observations of the rosacea patients, looking for the Demodex mites association using standardized skin-surface biopsy. With those first observations we started to think in this novel hypothesis. We thank Maria Ines Bax and Don Bax for the grammatical and orthographic correction of the article. Finally we thank the Professor, Jorge Arrese, for his comments and help regarding the search with the bibliographic material during the preparation of this document. References [1] O’Reilly N, Menezes N, Kavanagh K. Positive correlation between serum immunoreactivity to Demodex-associated Bacillus proteins and erythematotelangiectatic rosacea. Br J Dermatol 2012;167:1032–6. http:// dx.doi.org/10.1111/j.1365-2133.2012.11114.x. [2] http://www.healthxchange.com.sg/healthyliving/DietandNutrition/Pages/AsianFlush-Syndrome-Is-Alcohol-Giving-You-a-Red-Face.aspx. [3] Thomasson HR, Crabb DW, Edenberg HJ, Li TK, Hwu HG, Chen ChC, Eng-Kung Yeh EK, Yin SJ. Low frequency of the ADH2⁄2 allele among Atayal natives of Taiwan with alcohol use disorders. Alcohol Clin Exp Res 1994;18(3):640–3. http://dx.doi.org/10.1111/j.1530-0277.1994.tb00923.x. [4] Lee Ki-Hwan, Kim Ho-Seung, Jeong Han-Seung, Lee Yong-Sung. Chaperonin GroESL mediates the protein folding of human liver mitochondrial aldehyde dehydrogenase in Escherichia coli. Biochem Biophys Res Commun 2002;298:216–24. [5] Karlin S, Brocchieri L. Heat shock protein 60 sequence comparisons: duplications, lateral transfer, and mitochondrial evolution. Proc Natl Acad Sci USA 2000;97:11348–53. [6] Szlachcic A. The link between Helicobacter pylori infection and rosacea. J Eur Acad Dermatol Venereol 2002 Jul;16(4):328–33.
[7] Salmela KS, Roine RP, Koivisto T, Höök-Nikanne TU, Kosunen TU, Salaspuro M. Characteristics of Helicobacter pylori alcohol dehydrogenase. Gastroenterology 1993;105:325–30. [8] Salmela KS, Roine RP, Höök-Nikanne TU, Salaspuro M. Acetaldehyde and ethanol production by Helicobacter pylori. Scand J Gastroenterol 1994;29:309–12. [9] Roine RP, Salmela KS, Höök-Nikanne TU, Salaspuro M. Alcohol dehydrogenase mediated acetaldehyde production by Helicobacter pylori – a possible mechanism behind gastric injury. Life Sci 1992;51:1333–7. [10] Ayres S. Pityriasis folliculorum (Demodex). Arch Derm Syphilol 1930;21:19–24. http://dx.doi.org/10.1001/archderm.1930.01440070027002. [11] Ayres Jr S, Anderson NP. Demodex folliculorum: its role in the etiology of acne rosacea. Arch Dermatol 1932;25:89–98. [12] Ayres Jr S, Ayres III S. Demodetic eruptions (demodicidosis) in the human. 30 years’ experience with 2 commonly unrecognized entities: ‘‘Pityriasis folliculorum (Demodex)’’ and acne rosacea (Demodex type). Arch Dermatol 1961;83:816–27. [13] Forton F, Seys B. Density of Demodex folliculorum in rosacea: a case-control study using standardized skin-surface biopsy. Dermatol 1993;128(6):650–9. [14] Ya-e Zhao, Li Hu, Li-ping Wu, Jun-xian Ma. Retrospective analysis of the association between Demodex infestation and rosacea. Arch Dermatol 2010;146:896–902. [15] Lacey N, Delaney S, Kavanagh K, Powell FC. Mite-related bacterial antigens stimulate inflammatory cells in rosacea. Br J Dermatol 2007;157: 474–81. [16] Kuhnigk T et al. Bacillus oleronius sp. a member of the hindgut flora of the termite Reticulitermes santonensis (Feytaud). Can J Microbiol 1995;41: 699–706. [17] Kaihovaara P., Salmela K.S., Roine R.P., Kosunen T.U., Salaspuro M. Purification and characterization of Helicobacter pylori alcohol dehydrogenase. Alcohol Clin Exp Res 1994;18:1220–1225. [18] http://themedicalbiochemistrypage.org/es/ethanol-metabolism-sp.php#chronic. [19] Gu J.W, Bailey A.P, Sartin A., Makey I., Brady A.L. Ethanol stimulates tumor progression and expression of vascular endothelial growth factor in chick embryos. 2004 American Cancer Society Published online 13 December 2004 in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/cncr.20781. [20] Campuzano-Maya G. An optimized 13C urea breath test for the diagnosis of H. pylori infection. World J Gastroenterol 2007;13:5454–64. [21] Väkeäinen S, Mentula S, Nuutinen H, Salmela KS, Jousimies-Somer H, Färkklä M, et al. Ethanol-derived microbial production of carcinogenic acetaldehyde in achlorhydric atrophic gastritis. Scand J Gastroenterol 2002;37(6):648–55. [22] Cribier B. Physiopathology of rosacea. Ann Dermatol Venereol 2014;141(Suppl 2):S158–64. http://dx.doi.org/10.1016/S0151-9638(14)70153-X. [23] Akilov OE, Mumcuoglu KY. Association between human demodicosis and HLA class I. Clin Exp Dermatol 2003;28:70–3. [24] Roine RP, Salmela KS, Salaspuro M. Alcohol metabolism in Helicobacter pyloriinfected stomach. Ann Med 1995;27(5):583–8. [25] Salmela K.S1, Sillanaukee P., Itälä L., Väkeväinen S., Salaspuro M., Roine R.P.Binding of acetaldehyde to rat gastric mucosa during ethanol oxidation. J Lab Clin Med 1997;129(6):627–33. [26] Correa P, Cuello C, Duque E, Burbano LC, García FT, Bolanos O, et al. Gastric cancer in Colombia. III. Natural history of precursor lesions. J Natl Cancer Inst 1976;57:1027–35. [27] Correa P., Piazuelo M.B. The gastric precancerous cascade. J Dig Dis. 2012;13(1):2–9. DOI: 10.1111/j.1751-2980.2011.00550.x. [28] Correa P. Cáncer gástrico: una enfermedad infecciosa. Rev Colomb Cir 2011;26:111–7. [29] Correa P, Fontham ET, Bravo JC, et al. Chemoprevention of gastric dysplasia: randomized trial of antioxidant supplements and anti-helicobacter pylori therapy. J Natl Cancer Inst 2000;92:1881–8. [30] Szlachcic A, Sliwowski Z, Karczewska E, Bielan´ski W, Pytko-Polonczyk J, Konturek SJ. Helicobacter pylori and its eradication in rosacea. J Physiol Pharmacol 1999 Dec;50(5):777–86. [31] Bikowski JB, Del Rosso JQ. Demodex dermatitis: a retrospective analysis of clinical diagnosis and successful treatment with topical crotamiton. J Clin Aesthet Dermatol 2009 Jan;2(1):20–5. [32] Taieb A, Ortonne JP, Ruzicka T, Roszkiewicz J, Berth-Jones J, Peirone MH, Jacovella J. The ivermectin Phase III study group. Superiority of ivermectin 1% cream over metronidazole 0.75% cream in treating inflammatory lesions of rosacea: a randomized, investigator-blinded trial. Br J Dermatol 2014 Sep 16. http://dx.doi.org/10.1111/bjd.13408. [33] Forton F, Seys B, Marchal JL, Song AM. Demodex folliculorum and topical treatment: Acaricidal action evaluated by standardized skin surface biopsy. Br J Dermatol 1998;138:461–6. [34] Swenor M.E., Is permethrin 5% cream effective for rosacea? J Fam Pract Mar; 52(3):183–4. [35] Baldwin H.E. Systemic Therapy for Rosacea Skin Therapy Letter. 2007;12(2) http://www.medscape.com/viewarticle/554690_4.
Contents lists available at ScienceDirect
Medical Hypotheses journal homepage: www.elsevier.com/locate/mehy
Hypothesis of demodicidosis rosacea flushing etiopathogenesis q Mary Ann Robledo a,⇑, Mariana Orduz b a b
Calle 33# 42B-06 C.C Sandiego Torre sur 1122, Medellin, Colombia Universidad CES, Medellin, Colombia
a r t i c l e
i n f o
Article history: Received 21 October 2014 Accepted 22 January 2015
a b s t r a c t Most of the patients with erythematotelangiectatic rosacea are characterized by flushing, oedema and telangiectasia. The etiopathogenesis of the flushing in rosacea patients is unknown. Clinically the flushing in rosacea is similar to the ‘‘Asian flushing syndrome’’. Most Asians have an overactive alcohol dehydrogenase (ADH) that tends to break down alcohol into acetaldehyde faster. People with ‘‘Asians flushing syndrome’’ have a genetic disorder with the Aldehyde Dehydrogenase 2⁄2 (ALDH2⁄2) allele. This is the reason why they do not metabolize very well the acetaldehyde that comes from the alcohol, which means that acetaldehyde takes much longer to clear from their blood. ALDH2 enzyme is primarily responsible for oxidation of acetaldehyde derived from ethanol metabolism, as well as oxidation of various other endogenous and exogenous aldehydes. Acetaldehyde produces the vasodilatation in the ‘‘Asian flushing syndrome’’. The antibodies against the GroEl chaperonin protein, a 62-kDa heat shock protein were found in the Bacillus oleronius isolated from Demodex mites, in rosacea patients. The GroEl chaperonin protein is a protein that plays a key role in normal folding of ALDH2. If the GroEl chaperonin antibodies found in patients with rosacea, cross react with the human GroEl chaperonin protein, they will not fold normally the ALDH2, and then the enzyme will not metabolize the acetaldehyde. Many of the patients with rosacea have a concomitant infection with Helicobacter pylori in their stomach. The H. pylori produces high amounts of acetaldehyde, which comes from their metabolism of ethanol or carbohydrates. As a result, high amounts of acetaldehyde will circulate for longer time in the blood, until the liver CYP2E1(p450) enzyme system finally metabilizes the acetaldehyde, during that period of time the patients will experience a flushing as well as the people with the ‘‘Asian flushing syndrome’’ suffer when they drink ethanol. To prove the hypothesis it is necessary to find the cross reaction between the GroEl chaperonin antibodies against the B. oleronius and human GroEl chaperonin. Four groups of patients will be studied with or without the GroEl chaperonin antibodies, and H. Pylori. The production of acetaldehyde will be tested by the ethanol-derived microbial production method. If the hypothesis proves to be true, the treatment of Demodex mites and the H. pylori could improve the flushing in the rosacea patients and it will prevent the angiogenesis (telangiectasia), and the association of the gastric injury and carcinogenesis in those patients. Ó 2015 Elsevier Ltd. All rights reserved.
Introduction/background According to the article published by O’Reilly et al.: ‘‘Rosacea is a chronic inflammatory condition that affects the skin of the face and the eyes. Erythematotelangiectatic rosacea is characterized by flushing, oedema and telangiectasia. Patients with rosacea demonstrate elevated densities of Demodex mites in their skin compared with controls. A bacterium, Bacillus oleronius isolated from Demodex mites, from a patient with papulopustular rosacea has been demonstrated to produce antigenic proteins that may play a role in papulopustular and ocular rosacea. Eighty per cent (21/ q
Not sources of support.
⇑ Corresponding author. Tel.: + 574 2629678. E-mail address: [email protected] (M.A. Robledo). http://dx.doi.org/10.1016/j.mehy.2015.01.036 0306-9877/Ó 2015 Elsevier Ltd. All rights reserved.
26) of patients with erythematotelangiectatic rosacea showed serum reactivity to the 62- and 83-kDa proteins of B. oleronius, compared with 40% (9/22) of controls (P = 0Æ004). The 62-kDa protein was characterized by liquid chromatography-mass spectrometry (LC-MS) analysis and showed homology to GroEL chaperonin which provokes a strong immune response in mammals’’ [1]. ‘‘How well the body metabolizes or a break down alcohol is dependent on two enzymes: alcohol dehydrogenase (ADH) which converts alcohol into acetaldehyde and acetaldehyde dehydrogenase 2 (ALDH2) which breaks down acetaldehyde into harmless substances. Because 80% of Asians have an overactive alcohol dehydrogenase (ADH), they tend to break down alcohol into acetaldehyde faster, up to 100 times faster. As alcohol is broken down faster, there may be little to no alcohol ‘‘buzz’’’’ [2].
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‘‘The flushing syndrome described in oriental people, genetically the ADH2⁄2 allele encodes the b2 subunit; isozymes containing b2 sub-units oxidize alcohol faster in vitro than the b1b1 isozyme encoded by ADH2⁄1. Thus, the simplest explanation for this data is that individuals with b2 isozyme have a higher rate of ethanol oxidation, which is a deterrent to alcohol abuse and dependence in some individuals. The Atayal with alcohol use disorders also had a lower frequency of ALDH2⁄2 than the controls; this allele is known to be responsible for the alcohol-flushing reaction among Asians, and thereby deters drinking’’ [3]. ‘‘Many mitochondrial proteins are synthesized in the cytosol as precursor proteins and subsequently interact with one or more chaperonin proteins. Chaperonin can use the energy of ATP hydrolysis to keep the precursor proteins in an unfolded state so that they can be imported into mitochondria. Many matrix proteins are fabricated as precursors that have a matrix-targeting sequence at their N-terminus. The enzyme ALDH2 also contains 17-amino acids of matrix-targeting sequence and this peptide signal contains all the information required for translocation from cytosol to the mitochondrial matrix. After transporting, the sequence is cleaved by matrix protease. Imported proteins like ALDH2 are then folded correctly with the assistance of matrix proteins designated heat shock protein (hsp), hsp 60 and hsp10. These chaperone proteins are essential for protein folding and multi subunit protein assembly in the mitochondria. In addition, GroES (in particular) and GroEL, the E. coli homolog of hsp10 and hsp60 mitochondrial chaperone proteins, respectively, play a key role in normal folding of recombinant ALDH2’’ [4,5]. Patients with rosacea have a common Helicobacter pylori bacteria infection in their stomach. ‘‘The H. pylori prevalence in rosacea patients was about 88%, compared to 65% in the non-ulcer dyspepsia (NUD) controls. A noticeable number of rosacea patients showed chronic active gastritis predominantly in antrum but also in the corpus, while those with non-ulcer dyspepsia (NUD) showed only mild gastritis confined to the antrum only’’ [6]. ‘‘The H. pylori shows alcohol dehydrogenase activity, which in the presence of ethanol leads to in vitro production of acetaldehyde, a toxic and highly reactive substance. The H. pylori produced acetaldehyde from exogenous or endogenous ethanol may be one of the pathogenesis mechanism behind gastric mucosal injury associated with this organism’’ [7–9].
The hypothesis/theory As it is explain in the Table 1: a number of articles confirm the hight association in the etiopathogenesis of the rosacea and Demodex mites infestation. [1,10–14]. Lacey and cols. found the B. oleronius as endosymbiotic bacteria in the gut of the Demodex mites [15]. In human’s skin, this bacillus may occur in the endospore form, which enters the digestive tract of Demodex mites when they consume oil and epithelial cells [16]. Eighty percent of patients with erythematotelangiectatic rosacea showed serum reactivity to the 62- and 83-kDa proteins of B. oleronius. The 62-kDa protein from the B. oleronius was characterized by liquid chromatography– mass spectrometry (LC–MS) analysis and showed homology to GroEL protein, a heat shock protein, that is necessary to fold the Aldehyde Dehydratase enzyme 2 (ALDH 2), [1,4]. The antibodies against the GroEl chaperonin protein from the bacteria could make a cross reaction against the human GroEl chaperonin protein. Additionally, ALDH 2 is not able to assemble in the mitochondria. The ethanol that comes from the oral intake or from carbohydrate metabolism from enteric bacteria and H. pylori will be metabolized by the alcohol dehydrogenize enzyme (ADH) to acetaldehyde [7–9,17]. The ADH and the ALDH2 enzymes are a NAD+ – NADH+H dependent. If the ALDH 2 enzyme could not fold because
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the GroEl chaperonin is blocked by cross reactive antibodies against the B. oleronius 62-kDa protein. Then, high concentrations of acetaldehyde could circulate in the blood system for a longer period of time until the liver CYP2E1(p450) enzyme system finally metabolizes the acetaldehyde. The liver metabolized actions take more time that the ALDH2 enzyme normally take. The CYP2E1 require NADPH to produce the final products [18]. The high acetaldehyde concentrations in the blood produce vasodilatation and redness ‘‘flushing’’. The flushing appears especially in the face such as the oriental people which suffer the ‘‘Asian flushing syndrome’’ after the ethanol intake (2,3). Chronically the acetaldehyde could also produce the angiogenesis and the telangiectasia by the expression of Vascular Endothelial Growth Factor (VEGF) that was experimentally demonstrated by the chick embryo chorioallantoic membrane model (CAM) [19].
Evaluation of the hypothesis To search the patients it will be necessary to look for the clinical features of erythematotelangiectatic rosacea, which are characterized by flushing, oedema and telangiectasia. To find the GroEl chaperonin antibodies in the rosacea patients it is important to look for the Demodex mites, by using standardized skin-surface biopsy in them [13]. Skin-surface biopsy is also needed to rule out the Demodex in the negative controls individuals. An optimized 13C urea breath test is required for the diagnosis of H. pylori in order to find the positive controls, and to exclude the infection of H. pylori in the negative controls [20]. Endoscopic procedures will be necessary only if the 13C urea breath test is questioned. Patients with the ‘‘Asian flushing syndrome’’ with the genetic disorder with the Aldehyde Dehydrogenase 2⁄2 (ALDH2⁄2) allele must be disqualified of the study. It is indispensable to confirm that the antibodies detected against the GroEl chaperonin, 62 KDa hsp, from B. oleronius make a cross reaction against the human GroEl chaperonin protein, using ELISA or western blot assay with both proteins, and using the adequate negative and positive controls [1]. The four following groups of patients will be studied: (1) Patients with demodicidosis eritematotelangiectasia rosacea with positive antibodies against GroEl chaperonin and positive to H. pylori gastric infection (++). (2) Patients with demodicidosis eritematotelangiectasia rosacea with positive antibodies against GroEl chaperonin and negative to H. pylori gastric infection (+ ). (3) Patients with negative antibodies against GroEl chaperonin and positive to H. pylori gastric infection ( +). (4) Patients or a person with negative antibodies against GroEl chaperonin human protein and negative to H. pylori gastric infection ( ). Following the method described by Väkeäinen, and cols. in: ‘‘Ethanol-derived microbial production of carcinogenic acetaldehyde in achlorhydric atrophic gastritis: for the in vivo study, glucose or ethanol was infused via a nasogastric tube to the stomach of seven achlorhydric atrophic gastritis patients and five healthy controls. Gastric juice samples for ethanol and acetaldehyde determinations and microbial analysis were obtained at 30 and 60 min after the infusions. For the in vitro study, gastric juice samples from 14 atrophic gastritis patients and 16 controls were obtained during gastroscopy, where after the samples were incubated for 2 h with 1% ethanol at 37 degrees C and acetaldehyde was determined’’ [21]. The study of acetaldehyde could be performed by the same methods used in the article: ‘‘Characteristics
410 Table 1 Etiophatogenesis pat way of rosacea flushing.
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of H. pylori alcohol dehydrogenase: to study the acetaldehyde produced by cytosol during incubation with ethanol could be measured by spectrophotometrical determination of the aldehyde dehydrogenase activities and with head space gas chromatography’’ [7–9]. Concomitantly, clinical observations of flushing symptoms during the standardized ethanol intake test must be evaluated in the four groups of patients. We will demonstrate that the hypothesis is true if the first group (++), has higher levels of acetaldehyde that last longer in time when they have the flushing, using the standardized ethanol intake amount test, in comparison of the other groups and we expect to have negative de ( ) control group. Patients of the second group (+ ): if they have positive levels of acetaldehyde they also help to prove the hypothesis, but, negative levels means that the association with H. pylori will be necessary to have the flushing. Patients in the third group ( +), will be positive because the H. pylori produces acetaldehyde as it has been proved all ready [7–9]. Consequences of the hypothesis and discussion If the antibodies cross react against the human GroEl chaperonin and the acetaldehyde concentrations are higher in the first group of patients and negative in the fourth group (negative control), we can confirm that the association of Demodex mites with the B. oleronius endosymbiotic bacteria antibodies and the H. pylori gastric infection play a pathogenic role in the rosacea flushing and telangiectasia angiogenesis. It is already proofed that high acetaldehyde concentration is the cause of the ‘‘Asian flushing syndrome’’; it is clinically identical to the rosacea flushing. The rosacea telangiectasia angiogenesis could be explained by the chronically acetaldehyde circulation that produce the VEGF, that was experimentally demonstrated by the CAM [19]. Salvado et al, found that the Cathelicidin LL-37 induces angiogenesis via PGE2– EP3 signaling in endothelial cells that also increase the angiogenesis in rosacea patients. The frequent association, of the Demodex mite and the H. pylori in rosacea patients has been reported [6]. The connection between these two agents may explain the increase of the flushing and the angiogenesis in the face of the rosacea patients and also the internal gastric injury. Cribier, recently published the article ‘‘Physiopathology of rosacea’’, and he quoted: ‘‘For a long time rosacea was thought to be mainly a vascular disorder. In the past ten years many other concepts have emerged, such as the neurovascular aspects and involvement of innate immunity. There is obviously a genetic part in rosacea, as it is much more common in people with fair skin, blue eyes and Celtic ascendance. The same people are submitted to continental weather, with major temperature seasonal variations. Erythema and telangiectasia result from dilated superficial capillaries that have bizarre shapes, and induce constant edema of the dermis. This might be a favoring factor for Demodex colonization, which plays a major role in rosacea. Inflammation is always present, even in erythematotelangiectatic subtypes. It involves innate immunity, in response to environmental factors, like Demodex and its own biotope, resulting in overproduction of LL37, a proinflammatory peptide able to induce skin inflammation in an animal model, through activation of inflammatory cells. Tool like receptors are involved in the activation of innate immunity. Demodex is the cause of granulomas seen in papulopustular rosacea, but it is also always present in the erythematotelangiectatic subtype. Colonization by Demodex is nevertheless not decreased with conventional treatments of rosacea, like tetracyclins and metronidazole. This might be due to induction of inflammation by bacteria hosted by Demodex, like B. oleronius, and dozens of bacteria that are being investigated. Finally, rhinophyma is linked to both vascular
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changes and activation of fibrosis, involving TGF beta’’ [22]. We are agreeing with Cribier, that most of the immunological reactions in rosacea are due by the Demodex and their endosybiotic bacteria. If our hypothesis is prove to be true, the antibodies against the GroEl chaperonin and the acetaldehyde produced by H. pylori in a concomitant gastric infections are responsible for the symptoms of ‘‘flushing’’ and the erythema and telangiectasia in rosacea patients. The flushing symptom is not explained by the actinic damage in those patients. It is true that many rosacea patients could have, off course, concomitant actinic damage, but not all of them have strong sun damage, because we have patient’s photo type IV and V with rosacea, in our experience here in the tropic area of Colombia, with little actinic damage and with demodicidosis rosacea flushing and erythema. Akilov and Mumcuoglu has been established, ‘‘that there is a positive correlation between high density of Demodex mites and the presence of, HLA Cw2 and Cw4,’’ [23]. This indicates that there is a genetically susceptibility to acquire the Demodex mites infestation. This etiopathogenesis rosacea flushing pathway hypothesis could complement the knowledge of the pathogenic pathways of gastric injury. Two hypotheses are well described and complement each other. One is with the acetaldehyde that inhibits gastric mucosal regeneration and forms stable adducts with mucosal proteins [24]. ‘‘Formation of acetaldehyde adducts occurred relatively rapidly within 30 min and even at low acetaldehyde levels (5 lmol/L). Stable adducts represented 77% ± 5% (mean ± SEM) of the total adducts formed. In the presence of ethanol, acetaldehyde production and adduct formation took place in a concentration and time- dependent manner. 4-Methylpyrazole and sodium azide inhibited acetaldehyde production to 7% ± 1% of control and decreased the amount of acetaldehyde adducts to 55% ± 8%. Enhanced acetaldehyde formation (to 420% ± 50%) was clearly reflected in increased adduct formation (550% ± 110%). In conclusion, both exogenous and endogenous acetaldehyde binds to gastric mucosal proteins in vitro. Gastric mucosal acetaldehyde production and the consequent adduct formation could be a pathogenetic factor behind ethanol-associated gastric injury’’ [25]. And the other one is the Correa epidemiological studies in the gastric cancer and MALT lymphoma associated with the H. pylori gastric infection [26]. In the paper ‘‘The gastric precancerous cascade’’ explains Correa´s cascade, based in: ‘‘The presence of virulent factors in the infecting H. pylori strain is a known determinant factor of the outcome of the infection. Infection with cag-positive vacA s1m1 strains is associated with precancerous lesions and the development of gastric cancer; while persistent later renamed non-atrophic gastritis (NAG), associated to cag-negative vacA s2m2 does not increase the risk of cancer’’ [27]. Our hypothesis could explain the flushing and the angiogenesis in erythematotelangiectatic rosacea patients. The angiogenesis could play an important role in the pathogenesis of cancer and in the cancer progression. Gu et al. quoted: ‘‘Growth and expansion of tumor masses are dependent strictly on the sustained formation of new blood vessels, a process termed angiogenesis. We recently reported that physiologically relevant levels of ethanol induced VEGF expression and angiogenesis both in models of cell culture and in the chick chorioallantoic membrane (CAM). Therefore, we hypothesized that ethanol-induced angiogenesis and VEGF expression represent an important mechanism of cancer progression associated with alcoholic beverage consumption’’ [19]. The Acetaldehyde has been also well studied by the Scandinavian group, and is implicated in the gastric injury and carcinogenesis [7–9,17,21,24,25]. The H. pylori gastric infection and Demodex mite’s skin infestation are both the most common human infection and infestation, both are chronic and they can be acquired since childhood
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[12,28]. These microorganisms have been described as human normal microbiota and for a long time, they were considered nonpathogenic, but the knowledge has changed, and both are playing an important role in the pathogenesis of rosacea and in the gastric diseases [1,9–14,21,24,25]. If we make an early diagnosis of both agents; and if we treat them efficiently and prevent the infection and infestation of both microorganisms; we can possibly control the rosacea, and also will prevent gastric dysplasia, gastric cancer and MALT lymphoma [29]. Szlachcic et al. said: ‘‘The eradication of H. pylori leads to a dramatic improvement of symptoms of rosacea and reduction in related gastrointestinal symptoms, gastritis, hypergastrinemia and gastric acid secretion’’ [30]. We consider that it is necessary to treat the Demodex mites with topical acaricidal like, crotamiton [31], ivermectin [32], permetrin [33,34], and antibiotic as tetracycline [35]. It is very important to search in the family members the asymptomatic contacts in order to prevent the reinfestation of the Demodex mites. This will be controlled by using standardized skin-surface biopsy and the H. pylori gastric bacteria performing the 13C urea breath test. It will be necessary to advise these patients to decrease the alcohol and high carbohydrate intake while the H. pylori and Demodex are present in them. As in many other infectious diseases, the line between health and disease is due by the genetic host susceptibility, the virulence of the microorganism, and the way that the immune system responds. Conflict of interest The author has no potential conflict of interest. This work has not been financially supported. Acknowledgments We thank our father and grandfather Dr. Mario Robledo – Villegas (1927–2010) , pathologist and dermatopathologist, who started with us the studies and observations of the rosacea patients, looking for the Demodex mites association using standardized skin-surface biopsy. With those first observations we started to think in this novel hypothesis. We thank Maria Ines Bax and Don Bax for the grammatical and orthographic correction of the article. Finally we thank the Professor, Jorge Arrese, for his comments and help regarding the search with the bibliographic material during the preparation of this document. References [1] O’Reilly N, Menezes N, Kavanagh K. Positive correlation between serum immunoreactivity to Demodex-associated Bacillus proteins and erythematotelangiectatic rosacea. Br J Dermatol 2012;167:1032–6. http:// dx.doi.org/10.1111/j.1365-2133.2012.11114.x. [2] http://www.healthxchange.com.sg/healthyliving/DietandNutrition/Pages/AsianFlush-Syndrome-Is-Alcohol-Giving-You-a-Red-Face.aspx. [3] Thomasson HR, Crabb DW, Edenberg HJ, Li TK, Hwu HG, Chen ChC, Eng-Kung Yeh EK, Yin SJ. Low frequency of the ADH2⁄2 allele among Atayal natives of Taiwan with alcohol use disorders. Alcohol Clin Exp Res 1994;18(3):640–3. http://dx.doi.org/10.1111/j.1530-0277.1994.tb00923.x. [4] Lee Ki-Hwan, Kim Ho-Seung, Jeong Han-Seung, Lee Yong-Sung. Chaperonin GroESL mediates the protein folding of human liver mitochondrial aldehyde dehydrogenase in Escherichia coli. Biochem Biophys Res Commun 2002;298:216–24. [5] Karlin S, Brocchieri L. Heat shock protein 60 sequence comparisons: duplications, lateral transfer, and mitochondrial evolution. Proc Natl Acad Sci USA 2000;97:11348–53. [6] Szlachcic A. The link between Helicobacter pylori infection and rosacea. J Eur Acad Dermatol Venereol 2002 Jul;16(4):328–33.
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