Dina M. Abo-Elmatty

Cisplatin-induced cardiotoxicity: Mechanisms and cardioprotective strategies.

Increased oxidative stress and apoptosis have been implicated in the cardiotoxicity that limits the clinical use of cisplatin as an anti-tumoral drug. Our study was conducted to evaluate the protective potential of acetyl-l-carnitine, DL-α-lipoic acid and silymarin against cisplatin-induced myocardial injury. Eighty male albino rats were divided into eight groups. The first four groups were treated with normal saline, acetyl-l-carnitine (500mg/kg, i.p.), DL-α-lipoic acid (100mg/kg, p.o.) and silymarin (100mg/kg, p.o.) respectively, for 10 successive days. The remaining groups were treated with the same doses of normal saline, acetyl-l-carnitine, DL-α-lipoic acid and silymarin, respectively, for 5 successive days before and after a single dose of cisplatin (10mg/kg, i.p.). Serum activities of lactate dehydrogenase (LDH), creatine kinase (CK), creatine kinase isoenzyme MB (CK-MB) and plasma cardiac troponin I (cTnI) concentration were estimated. Malondialdehyde (MDA), reduced glutathione (GSH) contents, superoxide dismutase activity (SOD) and protein content in cardiac tissues were measured. Moreover, integrity of both mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) was also examined. Cisplatin-treated rats experienced a significant elevation of serum activities of LDH, CK, CK-MB and cTnI plasma concentration. These effects were accompanied by a significant increase in MDA level. On the other hand, a significant decrease in GSH content, SOD activity and total protein content was observed. In addition, both mtDNA and nDNA were heavily damaged. However, acetyl-l-carnitine, DL-α-lipoic acid and silymarin significantly attenuated the cisplatin-evoked disturbances in the above-mentioned parameters. In conclusion, the former drugs were proven to be potential candidates to ameliorate cisplatin-induced cardiotoxicity.

Acetyl-l-carnitine and α-lipoic acid affect rotenone-induced damage in nigral dopaminergic neurons of rat brain, implication for Parkinson's disease therapy

Although the mechanisms of neurodegeneration in Parkinsons disease are not fully understood, mitochondrial dysfunction, oxidative stress and environmental toxins may be involved. The current research was directed to investigate the protective role of two bioenergetic antioxidants, acetyl-L-carnitine and α-lipoic acid, in rotenone-parkinsonian rats. Ninety six male rats were divided into five groups. Group I is the vehicle-injected group, group II is the disease control group and was injected with six doses of rotenone (1.5 mg/kg/48 h, s.c.). Groups III, IV and V received rotenone in addition to acetyl-L-carnitine (100 mg/kg/day, p.o.), α-lipoic acid (50 mg/kg/day, p.o.) or their combination, respectively. Results showed that rotenone-treated rats exhibited bradykinesia and motor impairment in the open-field and square bridge tests. In addition, ATP level was decreased whereas lipid peroxides and protein carbonyls increased in the striata of rotenone-treated rats as compared to vehicle-treated rats. Treatment with acetyl-L-carnitine or α-lipoic acid improved the motor performance and reduced the level of lipid peroxides in rat brains as compared to rotenone group. Further, ATP production was enhanced along with acetyl-L-carnitine treatments (p≤0.05). Taken together, our study reinforces the view that acetyl-L-carnitine and α-lipoic acid are promising candidates for neuroprotection in Parkinsons disease.

Bacterial Community Analyses of Two Red Sea Sponges

Red Sea sponges offer potential as sources of novel drugs and bioactive compounds. Sponges harbor diverse and abundant prokaryotic communities. The diversity of Egyptian sponge-associated bacterial communities has not yet been explored. Our study is the first culture-based and culture-independent investigation of the total bacterial assemblages associated with two Red Sea Demosponges, Hyrtios erectus and Amphimedon sp. Denaturing gradient gel electrophoresis fingerprint-based analysis revealed statistically different banding patterns of the bacterial communities of the studied sponges with H. erectus having the greater diversity. 16S rRNA clone libraries of both sponges revealed diverse and complex bacterial assemblages represented by ten phyla for H. erectus and five phyla for Amphimedon sp. The bacterial community associated with H. erectus was dominated by Deltaproteobacteria. Clones affiliated with Gammaproteobacteria were the major component of the clone library of Amphimedon sp. About a third of the 16S rRNA gene sequences in these communities were derived from bacteria that are novel at least at the species level. Although the overall bacterial communities were significantly different, some bacterial groups, including members of Alphaproteobacteria, Gammaproteobacteria, Acidobacteria, and Actinobacteria, were found in both sponge species. The culture-based component of this study targeted Actinobacteria and resulted in the isolation of 35 sponge-associated microbes. The current study lays the groundwork for future studies of the role of these diverse microbes in the ecology, evolution, and development of marine sponges. In addition, our work provides an excellent resource of several candidate bacteria for production of novel pharmaceutically important compounds.

Piracetam and vinpocetine ameliorate rotenone-induced Parkinsonism in rats.

Objective: To evaluate the neuroprotective effect of the nootropic drugs, piracetam (PIR) and vinpocetine (VIN), in rotenone-induced Parkinsonism in rats. Materials and Methods: Sixty male rats were divided into 6 groups of 10 rats each. The groups were administered vehicle, control (rotenone, 1.5 mg/kg/48 h/6 doses, s.c.), PIR (100 and 200 mg/kg/day, p.o.) and VIN (3 and 6 mg/kg/day, p.o.). The motor performance of the rats was evaluated by the open field and pole test. Striatal dopamine level, malondialdehyde (MDA), reduced glutathione (GSH) and tumor necrosis factor-α (TNF-α) were assayed. Histopathological study of the substantia nigra was also done. Results: Results showed that rotenone-treated rats exhibited bradykinesia and motor impairment in the open-field test. In addition, GSH level was decreased whereas MDA and TNF-α increased in striata of rotenone-treated rats as compared to vehicle-treated rats. Marked degeneration of the substantia nigra pars compacta (SNpc) neurons and depletion of striatal dopamine was also observed in the rotenone-treated rats. Treatment with PIR or VIN significantly reversed the locomotor deficits and increased striatal dopamine level. Treatment with VIN significantly (P < 0.05) reduced the striatal level of MDA and GSH in comparison to rotenone group whereas TNF-α production was found to be significantly decreased in PIR group (P < 0.05). Conclusion: VIN and PIR exhibit neuroprotective activity in rotenone-induced Parkinsonism. Hence, these nootropic agents may be considered as possible candidates in the treatment of Parkinsons disease.

Evaluation of glutathione S-transferase P1 genetic variants affecting type-2 diabetes susceptibility and glycemic control.

Introduction Type 2 diabetes mellitus (T2DM) is associated with increased production of reactive oxygen species and a reduction in antioxidant defenses leading to oxidative stress. Glutathione S-transferases (GSTs) modulate oxidative stress. The present cross-sectional study was aimed at investigating the association between the GSTP1 gene polymorphism and T2DM and to clarify their effect on the glycemic control parameters. Material and methods From the Egyptian population, we enrolled 112 T2DM patients and 188 healthy controls matched for age, sex and origin. Serum lipid profile, blood-glucose level, glycated hemoglobin (HbA1c) and body mass index (BMI) were measured. DNA was extracted from the blood samples. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to measure GSTP1 Ile105Val gene polymorphism of study participants. Results The frequency of the Val allele in exon 5 of the GSTP1 gene in patients with T2DM was higher than that observed in healthy controls (15.2% vs. 9.6%); the difference was considered statistically significant when compared to Ile allele carriers (p = 0.03). The presence of the GSTP1 heterozygous mutant allele Ile/Val was more common in subjects with T2DM than in the control group (30.4% and 19.2%, respectively; p = 0.02). Variation in the GSTP1 gene was associated with BMI (p = 0.02) and not associated with glycemic control parameters (fasting serum glucose and HbA1c) or smoking-related risk of T2DM. Conclusions GSTP1 gene polymorphism may play a significant role in increasing the susceptibility to and risk of T2DM and obesity regardless of smoking status and had no apparent effect on HbA1c in patients with diabetes mellitus.

Frequent inadequate supply of micronutrients in fast food induces oxidative stress and inflammation in testicular tissues of weanling rats.

Fast food is high in energy density and low in essential micronutrient density, especially zinc (Zn), of which antioxidant processes are dependent. We have tested the hypothesis that frequent fast food consumption could induce oxidative damage associated with inflammation in weanling male rats in relevance to Zn deprivation, which could adversely affect testis function. Zn and iron (in plasma and testicular tissue), plasma antioxidant vitamins (A, E, and C), as well as testicular superoxide dismutase (SOD) and reduced glutathione (GSH), lipid peroxidation indexes (thiobarbituric acid reactive substances (TBARS) and lipoprotein oxidation susceptibility (LOS)), and inflammatory markers (plasma C‐reactive protein (CRP) and testicular tumour necrosis factor‐alpha (TNF‐α)) were determined. Serum testosterone and histological examination of the testis were performed also. We found a severe decrease in antioxidant vitamins and Zn, with concomitant iron accumulation. Zinc deficiency correlated positively with SOD, GSH, anti‐oxidant vitamins and testosterone, and negatively with TBARS, LOS, CRP and TNF‐α, demonstrating a state of oxidative stress and inflammation. We concluded that micronutrient deficiency, especially Zn, enhanced oxidative stress and inflammation in testicular tissue leading to under‐development of testis and decreased testosterone levels.

C-reactive protein 1059G/C gene polymorphism, C-reactive protein levels and acute myocardial infarction.

Aims High-sensitivity C-reactive protein (hs-CRP) is an inflammatory marker, predicting the occurrence of acute myocardial infarction (AMI). Genetic predisposition to high baseline CRP might account for a high risk of heart diseases. Our study aimed at investigating an association of CRP 1059G/C gene polymorphism with plasma CRP levels and AMI in Egyptian patients. Methods Genotypes of 150 patients with AMI and 150 healthy sex and age-matched controls were analyzed using PCR–restriction fragment length polymorphism methods. hs-CRP concentrations were assessed. Results There was no significant association between CRP 1095G/C polymorphism and AMI. However, individuals with GG genotype had significantly higher plasma CRP concentration than those with GC and CC genotypes, in both controls (3.82 ± 1.03 vs. 2.34 ± 0.7; P = 0.001) and patients with AMI (8.39 ± 2.6 vs. 6.67 ± 2.4; P = 0.005). Conclusion Our results revealed that CRP 1059G/C gene variation influences plasma CRP levels. Conversely, this polymorphism was not associated with the risk for AMI.

Association of polymorphic markers of the catalase and superoxide dismutase genes with type 2 diabetes mellitus.

Our study aims at determining whether genetic polymorphisms of catalase (CAT 1167C/T) and superoxide dismutase (SOD +35 A/C) could be associated with type 2 diabetes mellitus (T2DM). The study was conducted on 105 Egyptian patients with T2DM and 115 control subjects. Genotypes were done by polymerase chain reaction-restriction fragment length polymorphism methods. Homeostatic model assessment of insulin resistance (HOMA-IR), CAT and SOD activities, glycated hemoglobin, and insulin and lipid profiles were assessed. CAT and SOD activities were significantly decreased in T2DM compared with the control subjects. T allele of CAT and C allele of SOD1 were significant risk factors for T2DM. No effects of CAT or SOD1 gene polymorphisms on glycated haemoglobin or on HOMA-IR were found. With regard to the enzymes activities, only +35 A/C of SOD1 was related to SOD activity. Genetic variants C1167T of CAT gene and +35 A/C of SOD1 gene has no role in insulin resistance in T2DM.

Relaxin-3 is associated with metabolic syndrome and its component traits in women

OBJECTIVES Relaxin-3 was found to play a role in appetite regulation, increasing food intake and body weight. The current study aimed to investigate the relation of relaxin-3 to metabolic syndrome and its component traits in women. DESIGN AND METHODS The study was conducted on 300 female subjects, 150 healthy control and 150 metabolic syndrome patients. The component traits of metabolic syndrome were determined for all participants. RESULTS Serum relaxin-3 level was significantly higher in the metabolic syndrome patients than in the healthy control group. It was also significantly correlated with all the component traits of metabolic syndrome. CONCLUSION The results suggest that metabolic syndrome is associated with increased serum relaxin-3 levels in women. Relaxin-3 might be considered as a potential biomarker of metabolic syndrome.

Association of estrogen receptor alpha gene polymorphisms with metabolic syndrome in Egyptian women

OBJECTIVE Metabolic syndrome is a risk factor for coronary heart diseases as well as diabetes, fatty liver and several cancers. The prevalence of metabolic syndrome in women appears to be increasing, particularly in women of childbearing age. In the present study, we assessed the association of estrogen receptor-alpha gene polymorphisms (XbaI and PvuII) with metabolic syndrome and its related phenotypes. MATERIALS/METHODS One hundred and fifty Egyptian female patients with metabolic syndrome (mean age 35.52±6.86) were compared with one hundred and fifty age matched healthy Egyptian women (controls). The component traits of metabolic syndrome were determined, and the XbaI and PvuII genotypes were assessed with the PCR-RFLP method. RESULTS Our data indicated a significant difference in the allele frequencies of XbaI, but not PvuII, between the metabolic syndrome and control groups (P=0.0003 and P=0.164). Carriers of the minor alleles of XbaI and PvuII gene polymorphisms, in either the homozygous or heterozygous form, were associated with high diastolic blood pressure, high total cholesterol and LDL-c levels, increased HOMA-IR values and decreased QUICKI values compared to carriers of the major allele. However, only the minor G allele of XbaI was associated with measures of adiposity, specifically, BMI and waist circumference. CONCLUSIONS The XbaI polymorphism of the estrogen receptor alpha gene is associated with metabolic syndrome. On the other hand, PvuII gene polymorphism is not associated with the occurrence of the disease in this sample of Egyptian women.