Shahid Beheshti University of Medical Sciences
ORCID: 0000-0002-3185-4426Publishes on Hair Growth and Disorders, Wound Healing and Treatments, melanin and skin pigmentation. 40 papers and 601 citations.
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The availability of 3D sponges combining proper biochemical, biophysical, and biomechanical properties with enhanced capacity of in vivo engraftment and vascularization is crucial in regenerative medicine. A simple process is developed to generate macroporous scaffolds with a well-defined architecture of interconnected pores from chicken egg white (EW), a material with protein- and growth factor-binding features which has not yet been employed in regenerative medicine. The physicomechanical properties and degradation rates of the scaffold are finely tuned by using varying concentrations of the cross-linker, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride, without alteration of the biochemical traits. In vitro, EW scaffolds supported active metabolism, proliferation, and migration of human dermal fibroblasts, thereby generating uniform cellular constructs. In vivo, subcutaneous implantation in mice reveals negligible immune reaction and efficient cell and tissue ingrowth. Angiogenesis into EW scaffolds is enhanced as compared to standard collagen type I sponges used as reference material, likely due to significantly higher adsorption of the proangiogenic factor vascular endothelial growth factor. In summary, a material is presented derived by facile processing of a highly abundant natural product. Due to the efficient subcutaneous engraftment capacity, the sponges can find utilization for soft tissue regeneration.
OBJECTIVE: Human amniotic membrane (HAM) is used as a supporter for limbal stem cell (LSC) expansion and corneal surgery. The aim of study is to use HAM extracts from healthy donors to enhance proliferation of LSCs in vitro and in vivo. MATERIALS AND METHODS: In this interventional experimental study, the effective and cytotoxic doses of the amniotic membrane extract eye drops (AMEED) was assessed by adding different concentrations of AMEED (0-2.0 mg/ml) to LSC cultures for 14 days. Subsequently, the expression levels of ATP-binding cassette sub-family G member 2 (ABCG2, a putative stem cell marker), cytokeratin 3 (K3, corneal maker), K12 and K19 (corneal-conjunctival cell makers) were assessed by real-time polymerase chain reaction (PCR). In the second step, the corneal epithelium of 10 rabbits was mechanically removed, and the right eye of each rabbit was treated with 1 mg/ml AMEED [every 2 hours (group 1) or every 6 hours (group 2)]. The left eyes only received an antibiotic. The corneal healing process, conjunctival infection, degree of eyelid oedema, degree of photophobia, and discharge scores were evaluated during daily assessments. Finally, corneal tissues were biopsied for pathologic evidences. RESULTS: In comparison to the positive control [10% foetal bovine serum (FBS)], 0.1-1 mg/ml AMEED induced LSC proliferation, upregulated ABCG2, and downregulated K3. There were no remarkable differences in the expression levels of K12 and K19 (P>0.05). Interestingly, in the rabbits treated with AMEED, the epithelium healing duration decreased from 4 days in the control group to 3 days in the two AMEED groups, with lower mean degrees of eyelid oedema, chemosis, and infection compared to the control group. No pathologic abnormalities were observed in either of the AMEED groups. CONCLUSION: AMEED increases LSCs proliferation ex vivo and accelerates corneal epithelium healing in vivo without any adverse effects. It could be used as a supplement for LSC expansion in cell therapy.
AIM: The aim of the study was to assess the effectiveness of vitamin D3 [1, 25(OH)2D3] treatment in IBD with regard to tumor necrosis factor-alpha (TNF-α) serum level and clinical disease activity index (CDAI). BACKGROUND: Vitamin D has immune-regulatory functions in experimental inflammatory bowel disease (IBD) and vitamin D deficiency is common in IBD patients. PATIENTS AND METHODS: This was a randomized clinical trial on 108 IBD patients with serum 25-OHD levels less than 30ng/ml, which divided into vitamin D and control groups. Vitamin D group received 50000 IU vitamin D3 for 12 weeks. Before and after the study, TNF-α and 25-OHD serum levels were measured by ELISA method. Data were analyzed using paired t-test, chi-square test and Spearman correlation coefficient. P-values less than 0.05 were considered statistically significant. RESULTS: Before the intervention no significant difference was found between baseline characteristics and TNF-α serum level of two groups. After intervention TNF-α serum level reduced but this reduction was not statistically significant (p= 0.07, 95% CI: -0.45 to 8.14). The mean serum 25-OHD level of vitamin D increased from 15.54 to 67.89, which was statistically significant (p= 0.00, 95% CI: -61.40 to -43.30). TNF-α level was also associated significantly with CDAI before (Spearman's rho: 0.3, p<0.0001) and after (Spearman's rho: 0.27, P=0.01) intervention. CONCLUSION: Oral supplementation vitamin D3 significantly increased serum vitamin D levels and insignificantly reduced serum TNF-α level. More studies with larger samples would be beneficial to assess vitamin D3 supplementation efficient effect in IBD.
Billions of dollars are annually invested in pharmaceutical industry and cosmetic sector with intent to develop new drugs and treatment strategies for alopecia. Because the hair looks an important characteristic of humans-an effective appendage in perception, expression of beauty, and preservation of self-esteem-the global market for hair loss treatment products is exponentially increasing. However, current methods to treat hair loss endure yet multiple challenges, such as unfavorable outcomes, nonpermanent and patient-dependent results, as well as unpredictable impacts, which limit their application. Over recent years, remarkable advances in the fields of regenerative medicine and hair tissue engineering have raised new hopes for introducing novel cell-based approaches to treat hair loss. Through cell-based approaches, it is possible to produce hair-like structures in the laboratory setting or manipulate cells in their native niche (in vivo lineage reprogramming) to reconstruct the hair follicle. However, challenging issues still exist with the functionality of cultured human hair cells, the proper selection of nonhair cell sources in cases of shortage of donor hair, and the development of defined culture conditions. Moreover, in the case of in vivo lineage reprogramming, selecting appropriate induction factors and their efficient delivery to guide resident cells into a hair fate-with the aim of reconstructing functional hair-still needs further explorations. In this study, we highlight recent advances and current challenges in hair loss treatment using cell-based approaches and provide novel insights for crucial steps, which must be taken into account to develop reproducible, safe, and efficient cell-based treatment.