Prevalence of the CRISPR-cas system and its association with antibiotic resistance in clinical Klebsiella pneumoniae isolates.

BACKGROUND AND OBJECTIVE(S): CRISPR-Cas is a prokaryotic adaptive immune system that protects bacteria and archaea against mobile genetic elements (MGEs) such as bacteriophages plasmids, and transposons. In this study, we aimed to assess the prevalence of the CRISPR-Cas systems and their association with antibiotic resistance in one of the most challenging bacterial pathogens, Klebsiella pneumoniae. MATERIALS AND METHODS: A total of 105 K. pneumoniae isolates were collected from various clinical infections. Extended-spectrum ß-lactamases (ESBLs) phenotypically were detected and the presence of ESBL, aminoglycoside-modifying enzymes (AME), and CRISPR-Cas system subtype genes were identified using PCR. Moreover, the diversity of the isolates was determined by enterobacterial repetitive intergenic consensus (ERIC)-PCR. RESULTS: Phenotypically, 41.9% (44/105) of the isolates were found to be ESBL producers. A significant inverse correlation existed between the subtype I-E CRISPR-Cas system's presence and ESBL production in K. pneumoniae isolates. Additionally, the frequency of the ESBL genes blaCTX-M1 (3%), blaCTX-M9 (12.1%), blaSHV (51.5%), and blaTEM (33.3%), as well as some AME genes such as aac(3)-Iva (21.2%) and ant(2'')-Ia (3%) was significantly lower in the isolates with the subtype I-E CRISPR-Cas system in comparison to CRISPR-negative isolates. There was a significant inverse correlation between the presence of ESBL and some AME genes with subtype I-E CRISPR-Cas system. CONCLUSION: The presence of the subtype I-E CRISPR-Cas system was correlated with the antibiotic-resistant gene (ARGs). The isolates with subtype I-E CRISPR-Cas system had a lower frequency of ESBL genes and some AME genes than CRISPR-negative isolates.

Gut microbiota in neurological diseases: Melatonin plays an important regulatory role.

Melatonin is a highly conserved molecule produced in the human pineal gland as a hormone. It is known for its essential biological effects, such as antioxidant activity, circadian rhythm regulator, and immunomodulatory effects. The gut is one of the primary known sources of melatonin. The gut microbiota helps produce melatonin from tryptophan, and melatonin has been shown to have a beneficial effect on gut barrier function and microbial population. Dysbiosis of the intestinal microbiota is associated with bacterial imbalance and decreased beneficial microbial metabolites, including melatonin. In this way, low melatonin levels may be related to several human diseases. Melatonin has shown both preventive and therapeutic effects against various conditions, including neurological diseases such as Alzheimer's disease, Parkinson's disease, and multiple sclerosis. This review was aimed to discuss the role of melatonin in the body, and to describe the possible relationship between gut microbiota and melatonin production, as well as the potential therapeutic effects of melatonin on neurological diseases.

Induction of proteome changes involved in the cloning of mcr-1 and mcr-2 genes in Escherichia coli DH5-α strain to evaluate colistin resistance.

OBJECTIVES: Plasmid genes, termed mobile colistin resistance-1 (mcr-1) and mobile colistin resistance-2 (mcr-2), are associated with resistance to colistin in Escherichia coli (E. coli). These mcr genes result in a range of protein modifications contributing to colistin resistance. This study aims to discern the proteomic characteristics of E. coli-carrying mcr-1 and mcr-2 genes. Furthermore, it evaluates the expression levels of various proteins under different conditions (with and without colistin). METHODS: Plasmid extraction was performed using an alkaline lysis-based plasmid extraction kit, whereas polymerase chain reaction was used to detect the presence of mcr-1 and mcr-2 plasmids. The E. coli DH5α strain served as the competent cell for accepting and transforming mcr-1 and mcr-2 plasmids. We assessed proteomic alterations in the E. coli DH5α strain both with and without colistin in the growth medium. Proteomic data were analysed using mass spectrometry. RESULTS: The findings revealed significant protein changes in the E. coli DH5α strain following cloning of mcr-1 and mcr-2 plasmids. Of the 20 proteins in the DH5α strain, expression in 8 was suppressed following transformation. In the presence of colistin in the culture medium, 39 new proteins were expressed following transformation with mcr-1 and mcr-2 plasmids. The proteins with altered expression play various roles. CONCLUSION: The results of this study highlight numerous protein alterations in E. coli resulting from mcr-1 and mcr-2-mediated resistance to colistin. This understanding can shed light on the resistance mechanism. Additionally, the proteomic variations observed in the presence and absence of colistin might indicate potential adverse effects of indiscriminate antibiotic exposure on treatment efficacy and heightened pathogenicity of microorganisms.

Gut microbiota and obesity: an overview of microbiota to microbial-based therapies.

The increasing prevalence of obesity and overweight is a significant public concern throughout the world. Obesity is a complex disorder involving an excessive amount of body fat. It is not just a cosmetic concern. It is a medical challenge that increases the risk of other diseases and health circumstances, such as diabetes, heart disease, high blood pressure and certain cancers. Environmental and genetic factors are involved in obesity as a significant metabolic disorder along with diabetes. Gut microbiota (GM) has a high potential for energy harvesting from the diet. In the current review, we aim to consider the role of GM, gut dysbiosis and significant therapies to treat obesity. Dietary modifications, probiotics, prebiotics, synbiotics compounds, using faecal microbiota transplant, and other microbial-based therapies are the strategies to intervene in obesity reducing improvement. Each of these factors serves through various mechanisms including a variety of receptors and compounds to control body weight. Trial and animal investigations have indicated that GM can affect both sides of the energy-balancing equation; first, as an influencing factor for energy utilisation from the diet and also as an influencing factor that regulates the host genes and energy storage and expenditure. All the investigated articles declare the clear and inevitable role of GM in obesity. Overall, obesity and obesity-relevant metabolic disorders are characterised by specific modifications in the human microbiota's composition and functions. The emerging therapeutic methods display positive and promising effects; however, further research must be done to update and complete existing knowledge.

Gut Microbiota and Colorectal Cancer Risk Factors.

Colorectal cancer is a type of gut cancer originating either from the rectum or colon. Genetic and environmental factors, such as the gut microbiome, play pivotal roles in colorectal cancer incidence rates. Therefore, we aimed to review the risk factors of CRC comprising gut bacteriomes and their intra-interactions with each other in the context of CRC development. Gut microbiota alteration, especially bacteriome alteration as the dominant player, seems to be the common feature amongst all risk factors. Although it is not quite obvious whether these alterations are the causes or the consequences of the tumorigenesis risk factors, they are common and almost universal among CRC-affected individuals. In addition, bacterial genotoxicity, biofilm formation, oxidative stress, bacterial metabolome, and dysbiosis are assessed in CRC development. The present study suggests that gut microbial alterations could be the key intermediate, as a cause or a consequence, between most risk factors of CRC and the way they promote or contribute to CRC development.

Postbiotics versus probiotics in early-onset colorectal cancer.

Probiotics and postbiotics mechanisms of action and applications in early-onset colorectal cancer (EOCRC) prevention and treatment have significant importance but are a matter of debate and controversy. Therefore, in this review, we aimed to define the probiotics concept, advantages and limitations in comparison to postbiotics, and proposed mechanisms of anti-tumor action in EOCRC prevention and treatment of postbiotics. Biotics (probiotics, prebiotics, and postbiotics) could confer the health benefit by affecting the host gut microbiota directly and indirectly. The main mechanisms of action of probiotics in exerting anticancer features include immune system regulation, inhibition of cancer cell propagation, gut dysbiosis restoration, anticancer agents' production, gut barrier function renovation, and cancer-promoting agents' reduction. Postbiotics are suggested to have different mechanisms of action to restore eubiosis against EOCRC, including modulation of gut microbiota composition, gut microbial metabolites regulation, and intestinal barrier function improvement via different features such as immunomodulatory, anti-inflammatory, antioxidant, and anti-proliferative properties. A better understanding of postbiotics challenges and mechanism of action in therapeutic applications will allow us to sketch accurate trials in order to use postbiotics as bio-therapeutics in EOCRC.

Amelioration of oxidative stress, cholinergic dysfunction, and neuroinflammation in scopolamine-induced amnesic rats fed with pomegranate seed.

OBJECTIVE: This study aimed to investigate the effects of pomegranate (Punica granatum L.) seed hydro-ethanolic extract (PSE) on cholinergic dysfunction, neuroinflammation, and oxidative stress in the scopolamine-induced amnesic rats. METHODS: The rats were given PSE (200, 400, and 800 mg/kg, gavage) for 3 weeks. In the third week, scopolamine was administered 30 min before the Morris water maze (MWM) and passive avoidance (PA) tests. Oxidative stress indicators, acetylcholinesterase (AChE) activity, and mRNA expression of necrosis factor (TNF)-α, interleukin (IL)-1ß, AChE, and M1 acetylcholine receptor (CHRM1) in the brain, were measured. RESULTS: PSE reduced the time (maximum 173%) and distance (maximum 332%) required to reach the platform during MWM learning (P < 0.001). In the prob test (P < 0.001), it increased the target area time (maximum 44%) and distance (maximum 30%). PSE also increased delay and light time (maximums of 86 and 48%, respectively) (P < 0.001), while decreasing the time in dark region of PA (maximums 727%) (P < 0.001). PSE also reduced malondialdehyde and AChE in the cortex (maximum 168 and 171%, respectively) and hippocampus (maximum 151 and 182%, respectively) (P < 0.001). In the PSE-treated groups, the levels of thiol and superoxide dismutase were increased in the cortex (maximum 54 and 65%, respectively) and hippocampus (maximum 90 and 51%, respectively) (P < 0.001). TNF-α, IL-1ß, and AChE expressions in the hippocampus were reduced by PSE (maximum 114, 137, and 106%, respectively, P < 0.01). Meanwhile, CHMR expression was increased (66%). CONCLUSION: PSE successfully alleviated scopolamine-induced memory and learning deficits in rats which is probably via modulating cholinergic system function, oxidative stress, and inflammatory cytokines.

Role of CRISPR-Cas system on antibiotic resistance patterns of Enterococcus faecalis.

Clustered regularly interspaced short palindromic repeat (CRISPR)-Cas systems are one of the factors which can contribute to limiting the development and evolution of antibiotic resistance in bacteria. There are three genomic loci of CRISPR-Cas in Enterococcus faecalis. In this study, we aimed to assess correlation of the CRISPR-Cas system distribution with the acquisition of antibiotic resistance among E. faecalis isolates. A total of 151 isolates of E. faecalis were collected from urinary tract infections (UTI) and dental-root canal (DRC). All isolates were screened for phenotypic antibiotic resistance. In addition, antibiotic resistance genes and CRISPR loci were screened by using polymerase chain reaction. Genomic background of the isolates was identified by random amplified polymorphic DNA (RAPD)-PCR. The number of multidrug-resistant E. faecalis strains were higher in UTI isolates than in DRC isolates. RAPD-PCR confirmed that genomic background was diverse in UTI and DRC isolates used in this study. CRISPR loci were highly accumulated in gentamycin-, teicoplanin-, erythromycin-, and tetracycline-susceptible strains. In concordance with drug susceptibility, smaller number of CRISPR loci were identified in vanA, tetM, ermB, aac6'-aph(2"), aadE, and ant(6) positive strains. These data indicate a negative correlation between CRISPR-cas loci and antibiotic resistance, as well as, carriage of antibiotic resistant genes in both of UTI and DRC isolates.

Homeobox B4 gene expression is upregulated by ghrelin through PI3-kinase signaling pathway in rat's bone marrow stromal cells.

OBJECTIVE: Ghrelin, a 28 amino acid peptide, has diverse physiological roles. Phosphatidylino-sitol-bisphosphate 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) are involved in some of the recognized actions of ghrelin. It has been shown that ghrelin upregulates HOXB4 gene expression but the real mechanism of this effect is not clear. METHODS: Rat bone marrow stromal cells (BMSCs) were cultured in DMEM. BMSCs were treated with ghrelin (100 µM) for 48 h. Real-time PCR for HOXB4 was performed from Control (untreated BMSCs), BG (BMSCs treated with 100 µM ghrelin), PD (BMSCs treated with 10 µM PD98059, a potent inhibitor of mitogen-activated protein kinase, and 100 µM ghrelin), LY (BM-SCs treated with 10 µM LY294002, a strong inhibitor of phosphoinositide 3-kinase, and 100 µM ghrelin) and SY (BMSCs treated with 10 µM LY294002 plus 10 µM PD98059, and 100 µM ghrelin) groups. Relative gene expression changes were determined using Relative expression software tool 9 (REST 9). RESULTS: HOXB4 gene has been overexpressed in ghrelin-treated BMSCs (p<0.05). PI3K inhi-bition by LY294002 significantly downregulated the ghrelin-induced overexpression of HOXB4 (p<0.05). CONCLUSION: We can conclude that ghrelin, through PI3K/Akt pathway, may improve BMSC transplantation potency by reducing its apoptosis. Moreover, upregulating HOXB4 in BMSC and its possible differentiation to HSCs might in the future open the doors to new treatment for hematologic disorders. Therefore, activating the PI3K/Akt pathway, instead of using a non-specific inducer, could be the principal point to increase the efficiency of BMSC-based cell therapies in the future.

A new decomposition mechanism for metal complexes under water-oxidation conditions.

Herein, water-oxidation reaction by cobalt(II) phthalocyanine, N,N'-bis (salicylidene) ethylenediamino cobalt(II), nickel(II) Schiff base (N,N'-bis (salicylidene)ethylenediamino nickel(II), nickel(II)) phthalocyanine-tetrasulfonate tetrasodium, manganese(II) phthalocyanine, 5,10,15,20-Tetraphenyl-21H,23H-porphine manganese(III) chloride, manganese(III) 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine chloride tetrakis(methochloride) was investigated using electrochemistry, UV-vis spectroscopy and spectroelectrochemistry. According to our results, a new decomposition pathway for these metal complexes under water-oxidation conditions was proposed. The produced metal oxide obtained by decomposition of metal complex under water -oxidation conditions not only catalyzes water-oxidation reaction but this metal oxide also accelerates decomposition of the corresponding complex to form higher amounts of the metal oxide. We hypothesize that such a mechanism could be investigated for many metal complexes under different oxidation or reduction reactions.

Electrochemical water oxidation by simple manganese salts.

Recently, it has been great efforts to synthesize an efficient water-oxidizing catalyst. However, to find the true catalyst in the harsh conditions of the water-oxidation reaction is an open area in science. Herein, we showed that corrosion of some simple manganese salts, MnCO3, MnWO4, Mn3(PO4)2 · 3H2O, and Mn(VO3)2 · xH2O, under the water-electrolysis conditions at pH = 6.3, gives an amorphous manganese oxide. This conversion was studied with X-ray absorption spectroscopy (XAS), as well as, scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDXS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), spectroelectrochemistry and electrochemistry methods. When using as a water-oxidizing catalyst, such results are important to display that long-term water oxidation can change the nature of the manganese salts.

A nickel(ii) complex under water-oxidation reaction: what is the true catalyst?

In the present study, the water-oxidizing activity of nickel(ii) phthalocyanine-tetrasulfonate tetrasodium (1), which is a stable Ni(ii) complex under moderate conditions, was investigated. The role of Ni oxide in water oxidation as a true catalyst was investigated. The electrodes after water oxidation by both the complex and Ni salt were analyzed and a relation was proposed between the decomposition of the Ni complex and water oxidation. On the surface of the electrode, there are some areas without any detectable nanoparticles; thus, the detection of such Ni oxides on the surface of the electrode is not easy in the first seconds of the reaction, even using some of the usual methods such as Scanning Electron Microscopy or electrochemical analysis. Such experiments indicated that a precise analysis is necessary to reject the role of nanoparticles in the presence of Ni phthalocyanine under water oxidation. The findings also showed that under water-oxidation conditions and in the presence of the complex, Ni oxide is a good candidate for a true catalyst.

Effect of Ghrelin on Caspase 3 and Bcl2 Gene Expression in H2O2 Treated Rat's Bone Marrow Stromal Cells.

Purpose: The antiapoptotic effect of ghrelin in various cell lines including bone marrow stromal cells (BMSCs) has been proved. However, the real mechanism of this effect is not clear. Caspase3 and Bcl2 are well-known pro- and antiapoptotic regulatory genes in eukaryotes. The aim of the study was to find out the effect of ghrelin on Caspase 3 and Bcl2 change in BMSCs. Methods: Rat BMSCs were cultivated in DMEM. Passage 3 BMSCs were treated with ghrelin 100 µM for 48 h. Real-time PCR for Caspase 3 and Bcl2 was carried out from B (untreated BMSCs), BH (BMSCs treated with 125 µM H2O2), BGH (BMSCs treated with 100 µM ghrelin then 125 µM H2O2) and BG (BMSCs treated with 100 µM ghrelin) groups. For immunofluorescence, cells were incubated with anti Caspase 3 and Bcl2monoclonal antibodies. Primary antibodies were visualized using the FITC method. All data are presented as means ± SEM. Values of P<0.05 were considered statistically significant. Results: Ghrelin decreased mRNA expressions of Caspase-3 significantly as compared to the BH group (P<0.05). Also, Bcl-2 gene expression showed an increment in BG group as compare with BH and BGH groups (P<0.05). A high present of Bcl-2 positive cells were observed in the BGH group while Caspase-3 positive cells were significantly decreased in the BGH group compared with the BH group (P<0.05). Conclusion: Ghrelin probably enhances BMSCs viability through regulation of pro- and antiapoptotic genes Caspase 3 and Bcl2. However the signaling pathway of this effect should be elucidated in the future.

Water oxidation by Ni(1,4,8,11-tetraazacyclotetradecane)2+ in the presence of carbonate: new findings and an alternative mechanism.

Herein, the water-oxidation reaction by Ni(1,4,8,11-tetraazacyclotetradecane)2+ in the presence of carbonate was reinvestigated by scanning electron microscopy, energy dispersive spectrometry, electrochemistry, and high-resolution spectroelectrochemical and hydrogen nuclear magnetic resonance spectroscopy methods. These methods showed that the complex was not stable under water-oxidation conditions. The role of nanosized particles or Ni ions on the surface of the electrode for water oxidation was studied and it is proposed that Ni ions or Ni oxides on the surface of the electrode are at least one of the candidates contributing to the observed catalysis.

Ghrelin Upregulates Hoxb4 Gene Expression in Rat Bone Marrow Stromal Cells.

OBJECTIVES: Ghrelin is a peptide which has a proliferative and antiapoptotic effect in many cells including bone marrow stromal cells (BMSCs). Homeobox protein B4 (HOXB4) is a transcription factor involved in stem cell regeneration and survival. The aim of the study was to find out the efect of ghrelin on Hoxb4 expression in BMSCs. MATERIALS AND METHODS: In this experimental study, rat BMSCs were cultivated in Dulbecco's Modified Eagle Medium (DMEM). Passage three BMSCs were treated with ghrelin 100 µM for 48 hours. Real-time polymerase chain reaction (PCR) was carried out from the untreated BMSCs (B), BMSCs treated with 125 µM H2O2 (BH), BMSCs treated with 100 µM ghrelin then 125 µM H2O2 (BGH) and BMSCs treated with 100 µM ghrelin (BG) groups. For immunofluorescence, cells were incubated with an anti-HOXB4 monoclonal antibody. Primary antibodies were visualized using the Fluorescein isothiocyanate (FITC) method. All data are presented as mean ± SEM and P<0.05 was considered as statistical significant. RESULTS: Hoxb4 expression significantly increased in the BG compared with BH and BGH groups. Furthermore, 100 µM ghrelin, increased the mean of HOXB4 positive immunoreactive cells compared to the BH group. CONCLUSIONS: Ghrelin probably enhances proliferation and viability of BMSCs through Hoxb4 upregulation. However, the signaling pathway and other biological outcomes of this effect should be elucidated in different stem cells.

Ghrelin Administration Increases the Bax/Bcl-2 Gene Expression Ratio in the Heart of Chronic Hypoxic Rats.

PURPOSE: Programmed cell death or apoptosis, is a biochemical procedure that initiates due to some conditions, including hypoxia. Bax and Bcl-2 are among the agents that regulate apoptosis. The amplification of the first one triggers the initiation of apoptosis, and the second one prevents it. Ghrelin is an endogenous peptide that antiapoptosis is its new effect. The aim of this study is to examine the effect of ghrelin on the Bax/Bcl-2 ratio. METHODS: Twenty four wistar rats were divided randomly in three groups; control, hypoxic + saline and hypoxic + ghrelin. Hypoxic animals lived in O2 11% for 2 weeks and received either saline or ghrelin subcutaneously daily. The bax and Bcl-2 gene expression were measured by Real-Time RT-PCR. RESULTS: Chronic hypoxia increased the Bax gene expression significantly compared with normal animals (P = 0.008), but the Bcl-2 was not affected by hypoxia. The Bax/Bcl-2 ratio also amplified significantly (P=0.005). Ghrelin administration significantly increased the Bax/Bcl-2 ratio in the hypoxic animals compared to the hypoxic + saline and normal groups (p=0.042 and P= 0.001, respectively). CONCLUSION: In the present study, animals' treatment with ghrelin leads to an increment of Bax/Bcl-2 ratio, which indicates a controversy related to cardioprotection of ghrelin.

Investigation of CTLA-4-318C/T gene polymorphism in cases with type 1 diabetes of Azerbaijan, Northwest Iran.

This study analyzed the association of CTLA-4-318C/T gene polymorphism with susceptibility, clinical course and laboratory findings of Type 1 diabetes (T1D). One hundred and fifty-three T1D patients and 189 healthy controls entered this study. CTLA-4-318C/T genotyping was performed by tetra-primer amplification refractory mutation system-polymerase chain reaction (T-ARMS-PCR) analysis. The allelic and genotypic frequencies of -318C/T gene polymorphism were similar in patients and controls. However, younger age, earlier age at onset, higher HbA1c levels, higher frequency of Glutamic acid decarboxylase antibodies (GADA) and Insulinoma Associated-2 Autoantibodies (IA-2A) were observed in T1D patient carriers of CT genotype. The current study demonstrates that although CTLA-4-318C/T polymorphism was not linked with a higher genetic risk for T1D, the presence of a CT genotype was associated with a younger age of onset, poor control of HbA1c level and positive anti-GAD or IA-2 serum autoantibodies in Iranian Azeri population.

Effects of hypo- and hyperthyroid states on herpes simplex virus infectivity in the rat.

OBJECTIVE: Available data from in vitro studies show that thyroid hormones (THs) regulate herpes simplex virus (HSV) gene expression and may modulate latency/reactivation of the virus. Whether infectivity of the virus is also affected by THs is not known. Using animal models (in vivo study) and Vero cell culture (in vitro study), we examined the effects of alterations in THs level on HSV-1 infectivity. METHODS: Rats were rendered hypo- and hyperthyroid by daily addition of methimazole and l-thyroxine into their drinking water, respectively. Euthyroid animals served as control. All animals were given a single dose of HSV-1 (10(7)TCID50, ip) and sacrificed 3 d later. The spleen of the animals was then removed and viral particles were recovered from the tissue extract through aseptic procedures. Serial dilution of the extracts was prepared and added to Vero cell culture. For the in vitro study, the cultures were pretreated with l-thyroxine and the viral particles were then added. Virus titration was determined by Reed-Muench quantal assay. RESULTS: The viral load of spleen in hyperthyroid rats was significantly lower (1000-fold) than that of the euthyroid rats. Similarly, in vitro presence of supraphysiologic levels of l-thyroxine in the culture media of Vero cells decreased virus infectivity. Interestingly, hypothyroid animals showed a significant increase (10-fold) in spleen viral load as compared to that of their euthyroid counterparts. CONCLUSIONS: These data clearly show that the HSV-1 infectivity is affected by THs, and suggest that THs or their analogs may have a potential application in prevention and/or treatment of viral infections.

Effect of ghrelin on aldolase gene expression in the heart of chronic hypoxic rat.

BACKGROUND: Chronic hypoxia causes apoptosis of cardiac myocytes, however, energy production by anaerobic glycolysis protects myocardium against hypoxia injuries. Aldolase A is a well-characterised key enzyme of the glycolysis pathway. Ghrelin, a 28-amino-acid peptide, synthesizes in the stomach and has protective roles in cardiovascular systems and also affects metabolic pathways. OBJECTIVES: Therefore, the aim of this study was to evaluate the effect of ghrelin on aldolase A gene expression after chronic hypoxia in the rat hearts. MATERIALS AND METHODS: Twenty four adult male wistar rats were randomly divided into three groups. Hypoxic rats with saline or ghrelin treatment were placed in a normobaric hypoxic chamber (O2 11 %), for two weeks. Controls remained in room air. Aldolase A gene expression was measured by Real-Time RT-PCR. RESULTS: the transcriptiom rate of Aldolase A in hypoxic animals did not change significantly compared to negative control ones. During chronic hypoxia, ghrelin treatment increased the amount of heart Aldolase A gene expression compared to negative controls (P = 0.029). Hypoxic animals that were treated with ghrelin were significantly more polycythemic than the controls and even hypoxic with saline treated rats (P < 0.001). CONCLUSIONS: It seems that ghrelin interferes in the cardiac metabolism through upregulation of glycolytic enzymes. In other words, it may protect heart from possible hypoxia induced damages.