Hazem Atta

The Clinical Use of Human Culture–Expanded Autologous Bone Marrow Mesenchymal Stem Cells Transplanted on Platelet-Rich Fibrin Glue in the Treatment of Articular Cartilage Defects A Pilot Study and Preliminary Results

Objective: To test the hypothesis that platelet-rich fibrin glue (PR-FG) can be used clinically as a scaffold to deliver autologous culture-expanded bone marrow mesenchymal stem cells (BM-MSCs) for cartilage repair and to report clinical results 1 y after implantation of MSCs PR-FG. Patients and Methods: Autologous BM-MSCs were culture expanded, placed on PR-FG intraoperatively, and then transplanted into 5 full-thickness cartilage defects of femoral condyles of 5 patients and covered with an autologous periosteal flap. Patients were evaluated clinically at 6 and 12 mo by the Lysholm and Revised Hospital for Special Surgery Knee (RHSSK) scores and radiographically by x-rays and magnetic resonance imaging (MRI) at the same time points. Repair tissue in 2 patients was rated arthroscopically after 12 mo using the International Cartilage Repair Society (ICRS) Arthroscopic Score. Study Design: Case series; level of evidence 4. Results: All patients’ symptoms improved over the follow-up period of 12 mo. Average Lysholm and RHSSK scores for all patients showed statistically significant improvement at 6 and 12 mo postoperatively (P < 0.05). There was no statistically significant difference between the 6 and 12 mo postoperative clinical scores (P = 0.18). ICRS arthroscopic scores were 8/12 and 11/12 (nearly normal) for the 2 patients who consented to arthroscopy. MRI of 3 patients at 12 mo postoperatively revealed complete defect fill and complete surface congruity with native cartilage, whereas that of 2 patients showed incomplete congruity. Conclusion: Autologous BM-MSC transplantation on PR-FG as a cell scaffold may be an effective approach to promote the repair of articular cartilage defects of the knee in human patients.

Role of polyunsaturated fatty acids in the management of Egyptian children with autism.

OBJECTIVE Estimation of free polyunsaturated fatty acids (PUFAs) in blood and evaluation of behavior of autistic children before and after taking fish oil (Efalex) were performed. DESIGN AND METHODS 30 autistic children (18 males and 12 females) aged 3-11 years and 30 healthy children as control group were included in this study. Tandem mass spectrometry and CARS were used to estimate the free PUFAs from dried blood spot and to evaluate the autistic behavior respectively. RESULTS Before taking Efalex, linolenic acid showed a significant reduction (71%), followed by docosahexaenoic acid (65%) and arachidonic acid (45%), while linoleic acid was the least affected PUFA (32%). After taking Efalex, 66% of autistic children showed clinical and biochemical improvement, linolenic acid and docosahexaenoic acid showed the highest levels after Efalex supplementation. CONCLUSION PUFA supplementation may play an important role in ameliorating the autistic behavior.

Efficacy of Mesenchymal Stem Cells in Suppression of Hepatocarcinorigenesis in Rats: Possible Role of Wnt Signaling

BackgroundThe present study was conducted to evaluate the tumor suppressive effects of bone marrow derived mesenchymal stem cells (MSCs) in an experimental hepatocellular carcinoma (HCC) model in rats and to investigate the possible role of Wnt signaling in hepato-carcinogenesis.MethodsNinety rats were included in the study and were divided equally into: Control group, rats which received MSCs only, rats which received MSCs vehicle only, HCC group induced by diethylnitroseamine (DENA) and CCl4, rats which received MSCs after HCC induction, rats which received MSCs before HCC induction. Histopathological examination and gene expression of Wnt signaling target genes by real time, reverse transcription-polymerase chain reaction (RT-PCR) in rat liver tissue, in addition to serum levels of ALT, AST and alpha fetoprotein were performed in all groups.ResultsHistopathological examination of liver tissue from animals which received DENA-CCl4 only, revealed the presence of anaplastic carcinoma cells and macro-regenerative nodules type II with foci of large and small cell dysplasia. Administration of MSCs into rats after induction of experimental HCC improved the histopathological picture which showed minimal liver cell damage, reversible changes, areas of cell drop out filled with stem cells. Gene expression in rat liver tissue demonstrated that MSCs downregulated β-catenin, proliferating cell nuclear antigen (PCNA), cyclin D and survivin genes expression in liver tissues after HCC induction. Amelioration of the liver status after administration of MSCs has been inferred by the significant decrease of ALT, AST and Alpha fetoprotein serum levels. Administration of MSCs before HCC induction did not show any tumor suppressive or protective effect.ConclusionsAdministration of MSCs in chemically induced HCC has tumor suppressive effects as evidenced by down regulation of Wnt signaling target genes concerned with antiapoptosis, mitogenesis, cell proliferation and cell cycle regulation, with subsequent amelioration of liver histopathological picture and liver function.

The Role of PDE5 Inhibitors in Heme Oxygenase–cGMP Relationship in Rat Cavernous Tissues

INTRODUCTION Heme oxygenase (HO) enzyme catalyzes oxidative degradation of heme to biliverdin and carbon monoxide (CO). CO shares many properties with nitric oxide (NO) including the activation of soluble guanyl cyclase. AIM To assess cavernous tissue HO activity and cyclic guanosine monophosphate (cGMP) levels in response to oral phosphodiesterase type 5 (PDE5) inhibitors. METHODS Seven hundred twenty male Sprague-Dawley rats, divided into six groups, were investigated. Group 1, controls; group 2 received sildenafil citrate orally; group 3 received vardenafil hydrochloride; and group 4 received tadalafil. Group 5 was subdivided into three equal subgroups, received the same dose of each drug added to the HO inhibitor, Zn protoporphyrin. Group 6 was subdivided into three equal subgroups, received the same dose of each drug added to the NO inhibitor, L-nitroarginine methylester. Eight rats from each group/subgroup were sacrificed at 0.5, 1, 2, 3, 4, 6, 18, 24, and 36 hours, respectively. MAIN OUTCOME MEASURES HO enzyme activity assay and cGMP tissue levels in dissected rat cavernous tissues. RESULTS Both cavernous tissue HO enzyme activity and cGMP levels were increased significantly in sildenafil-, vardenafil-, and tadalafil-treated rats compared with the controls, with significant decreases after either HO or NO inhibition. Cavernous tissue HO enzyme activity and cGMP showed a positive significant correlation (r = 0.854, P < 0.001). CONCLUSION The effects of PDE5 inhibitors in cavernous tissue are partly mediated through HO enzyme activity.

Effect of mesenchymal stem cell penile transplantation on erectile signaling of aged rats

Stem cell‐based therapy targeted at the penile tissue has been lately considered in preclinical studies. This work aimed to assess the effect of intracavernous administration of mesenchymal stem cells (MSCs) in aged rats (n = 100). They were subjected to single intracavernous injection (ICI) of 1.0 million MSCs, followed up for 3, 4 weeks, 3 and 4 months (each group 25 rats) and compared with both adult and aged controls (n = 50). In dissected cavernous tissues, cGMP and histopathology were assessed in addition to intracavernous pressure (ICP) measurement in some anaesthetised rats. The results showed that cavernous tissue cGMP was significantly increased in MSCs transplanted rats in all investigated groups compared with the controls. The mean cavernous cGMP levels after 3 and 4 months of MSCs transplantation were significantly increased compared with those after 3 or 4 weeks. Cavernous tissue ICP measurement showed significant increase in MSCs transplanted groups compared with the controls, more in the long‐term follow up than in the shorter one. Histopathological examination detected markedly dilated sinusoidal vascular spaces in the long‐term follow‐up study. It is concluded that stem cell‐based therapy is feasible for age‐associated erectile dysfunction and could improve erectile signaling.

Potential of bone marrow mesenchymal stem cells in management of Alzheimer's disease in female rats

Alzheimers disease (AD) has been called the disease of the century with significant clinical and socioeconomic impacts. Pharmacological treatment has limited efficacy and only provides symptomatic relief without long‐term cure. Accordingly, there is an urgent need to develop novel and effective medications for AD. Stem cell‐based therapy is a promising approach to handling neurodegenerative diseases. Therefore, the current study aimed to explore the possible therapeutic role of single intravenous injection of bone marrow derived mesenchymal stem cells (BM‐MSCs) after 4 months in management of AD in the experimental model. The work also extended to compare the therapeutic potential of BM‐MSCs with 2 conventional therapies of AD; rivastigmine and cerebrolysin administered daily. BM‐MSCs were able to home at the injured brains and produced significant increases in the number of positive cells for choline acetyltransferase (ChAT) and survivin expression, as well as selective AD indicator‐1 (seladin‐1) and nestin gene expression. Histopathological examination indicated that BM‐MSCs could remove beta‐amyloid plaques from hippocampus. Significant improvement in these biomarkers was similar to or better sometimes than the reference drugs, clearly showing the potential therapeutic role of BM‐MSCs against AD through their anti‐apoptotic, neurogenic and immunomodulatory properties.

Putative Role of Carbon Monoxide Signaling Pathway in Penile Erectile Function

INTRODUCTION Erectile response depends on nitric oxide (NO) generated by NO synthase (NOS) enzyme of the nerves and vascular endothelium in the cavernous tissue. NO activates soluble guanylate cyclase (sGC), leading to the production of cyclic guanosine monophosphate (cGMP). cGMP activates cGMP-dependent protein kinase that activates Ca(2+)/ATPase pump that activates Ca(2+)/K efflux pump extruding Ca(2+) across the plasma membrane with consequent smooth muscle cell relaxation. A role similar to that of NOS/NO signaling has been postulated for carbon monoxide (CO) produced in mammals from heme catabolism by heme oxygenase (HO) enzyme. AIM To assess CO signaling pathway for erectile function by reviewing published studies. METHODS A systematic review of published studies on this affair based on Pubmed and Medical Subject Heading databases, with search for all concerned articles. MAIN OUTCOME MEASURES Documentation of positive as well as negative criteria of CO/HO signaling focused on penile tissue. RESULTS The concept that HO-derived CO could play a role in mediating erectile function acting in synergism with, or as a potentiator for, NOS/NO signaling pathway is gaining momentum. CO/HO signaling pathway has been shown to partially mediate the actions of oral phosphodiesterase type 5 inhibitors. In addition, it was shown that the use of CO releasing molecules potentiated cavernous cGMP levels. However, increased CO production or release was reported to be associated, in some studies, with vasoconstriction. CONCLUSION This review sheds a light on the significance of cavernous tissue CO signaling pathway that may pave the way for creation of therapeutic modalities based on this pathway.

Retrovirus-mediated human heme oxygenase-1 (HO-1) gene transfer into rat endothelial cells: the effect of HO-1 inducers on the expression of cytokines.

The present study was conducted to investigate if the mechanism of human heme oxygenase-1 (HO-1) mediated angiogenesis was through the induction of vascular endothelial growth factor (VEGF). Also, the effect of HO-1 on the expression of transforming growth factor beta (TGF-beta),was studied in the presence and absence of HO-1 inducers. Rat lung microvessel endothelial cell line transduced with human HO-1 gene was subjected to cell culture (six separate experiments). mRNA extraction and reverse transcriptase polymerase chain reaction (RT-PCR) experiments, were performed to evaluate the expression of HO-1, VEGF, and TGF-beta in the presence and absence of HO inducers including H(2)O(2), endotoxin and snake venom metalloproteinase with disintegrin like activity(SnMP). ELISA technique was performed to evaluate the levels of the studied growth factors. The results of the study showed over expression of VEGF in endothelial cells transduced with HO-1 compared to control non-transduced endothelial cells. On the other hand, the expression of TGF-beta and its protein level were markedly inhibited in HO-1 transduced endothelial cells compared to control non-transduced cells. Endotoxin and SnMP showed more prominent effect on the expression of VEGF and suppression of TGF-beta in HO-1 transduced endothelial cells, suggesting that their effect is most probably mediated through induction of HO-1.

Heme oxygenase enzyme activity in seminal plasma of oligoasthenoteratozoospermic males with varicocele.

This work aimed to assess seminal plasma heme oxygenase (HO) enzyme activity in oligoasthenoteratozoospermia (OAT) males with varicocele. Ninety‐three men were divided according to their sperm count and clinical examination into: healthy fertile controls (n = 34), OAT without varicocele (n = 37) and OAT associated with varicocele (n = 22). They were subjected to semen analysis and estimation of seminal plasma HO enzyme activity in the form of bilirubin concentration. Seminal plasma HO enzyme activity decreased significantly in OAT cases compared with controls. Seminal plasma HO in OAT cases associated with varicocele decreased significantly compared with OAT cases without varicocele and healthy controls (mean ± SD; 109.2 ± 29.5, 283.6 ± 88.4, 669.5 ± 236.1 nMol bilirubin/mg ptn/min, P < 0.001). There was positive correlation between seminal plasma HO enzyme activity and sperm concentration, per cent of motile spermatozoa, number of motile spermatozoas ml−1 and significant negative correlation with sperm abnormal forms per cent. It is concluded that varicocele has a negative impact on seminal HO enzyme activity. Therefore, improved seminal picture after correcting varicocele repair might be related, in part, to improved HO action(s).

Effects of Losartan, HO‐1 Inducers or HO‐1 Inhibitors on Erectile Signaling in Diabetic Rats

INTRODUCTION Activation of the renin-angiotensin system which is common in diabetes mellitus might affect heme oxygenase (HO-1) gene expression. AIM Assessment of the effects of administration of angiotensin II (Ang II) receptor antagonist (losartan) with HO-1 inducer or inhibitor on erectile signaling in diabetic rats. MATERIALS AND METHODS Seventy male rats were divided equally into seven groups; healthy controls, streptozotocin-induced diabetic rats, rats on citrate buffer, diabetic rats on losartan, diabetic rats on HO-1 inducer (cobalt protoporphyrin [CoPP]), diabetic rats on losartan and CoPP, and diabetic rats on losartan and HO-1 inhibitor (stannus mesoporphyrin [SnMP]). MAIN OUTCOME MEASURE HO enzyme activity, HO-1 gene expression, cyclic guanosine monophosphate (cGMP) assay, intracavernosal pressure (ICP), and cavernous tissue sinusoids surface area. RESULTS HO-1 gene expression, HO enzymatic activity, and cGMP were significantly decreased in the cavernous tissue of diabetic rats. These parameters were significantly elevated with the use of CoPP that restored the normal control levels of HO enzyme activity. Administration of losartan exhibited a significant enhancing effect on these parameters compared with the diabetic group, but not restored to the control levels, whereas administration of CoPP combined with losartan led to the restoration of their normal levels. ICP demonstrated significant decline in diabetic rats. The use of CoPP and/or losartan led to its significant improvement compared with diabetic rats. Administration of either losartan and/or CoPP led to a significant increase in the cavernous sinusoids surface area of diabetic rats. Administration of losartan with SnMP significantly decreased the enhancing effect of losartan on the studied parameters. CONCLUSION The decline in erectile function in diabetes mellitus could be attributed to the downregulation of HO-1 gene expression. HO-1 induction added to Ang II receptor antagonist could improve erectile function.