Co-culture with neurotrophic factor secreting cells induced from adipose-derived stem cells: Promotes neurogenic differentiation Shahnaz Razavi a,⇑ , Mohamad Reza Razavi b , Mahsa Kheirollahi-Kouhestani c , Mohammad Mardani a , Fatemeh Sadat Mostafavi a a Department of Anatomical Sciences, School of Medicine, Isfahan University of Medical Sciences, Isfahan 81744-176, Iran b Molecular Parasitology Laboratory, Pasteur Institute of Iran, Tehran 1316943551, Iran c Institute of Genetic Medicine, International Centre for Life, Central Parkway, Newcastle upon Tyne, NE1 3BZ, United Kingdom article info Article history: Received 27 August 2013 Available online 21 September 2013 Keywords: Human adipose-derived stem cells Neurotrophic factor secretion Neurogenesis Neurodegenerative diseases abstract Adipose-derived stem cells (ADSCs) and bone marrow stem cells (BMSCs) can be equally proper in the treatment of neurodegenerative diseases. However, ADSCs have practical benefits. In this study, we attempted to induce the secretion of neurotrophic factors (NTF) in human ADSCs. We then evaluated the effects of co-culture with NTF secreting cells in neural differentiation of human ADSCs. Isolated human ADSCs were induced to neurotrophic factors secreting cells. To evaluate the in vitro effects of NTF-secreting ADSCs on neurogenic differentiation of ADSCs, we used neurogenic induction medium (control group), the combination of neurogenic medium and conditioned medium, or co-cultured NTF- secreting ADSCs which were encapsulated in alginate beads (co-culture) for 7 days. ELISA showed increased (by about 5 times) release of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in NTF-secreting ADSCs compared to human ADSCs. Real time RT-PCR analysis revealed that NTF- secreting ADSCs highly expressed NGF and BDNF. In addition, co-culture with NTF-secreting ADSCs could also promote neuronal differentiation relative to gliogenesis. Overall, NTF-secreting ADSCs secrete a range of growth factors whose levels in culture could promote neuronal differentiation and could support the survival and regeneration in a variety of neurodegenerative diseases. Ó 2013 Elsevier Inc. All rights reserved. 1. Introduction Mesenchymal stem cell (MSC)-based therapies may be efficient in the treatment of neurological diseases. The efficiency of MSCs as a clinical therapeutic implement for neurodegenerative diseases has been recently investigated in two points, transdifferentiation into neural cells and replacing damaged cells [1] or production of cytokines as trophic factors for support and regeneration of dam- aged nervous tissue [2–4]. Bone marrow stromal cells (BMSCs) were the first type of adult stem cells to successfully differentiate into neuronal cells and pro- mote neuronal survival in cerebral ischemia [2,5]. They have also been used in the functional recovery following spinal cord injury [6]. So; transplantation of MSCs can be enhancing regeneration of damaged neural tissues through secretion of cytokines and trophic factors [7]. Recent evidence suggests that the neurotrophic and neuropro- tective effects of induced BMSCs can enhance survival and regener- ation in a variety of neurodegenerative diseases [8–12]. However, BMSC harvest is an invasive and painful procedure that might yield few MSCs [13]. Therefore, an alternative cell source is preferred. Unlike bone marrow, adipose tissue is abun- dant and easily accessible. Moreover, its harvesting does not require any invasive and painful procedures [14]. Adipose-derived stem cells (ADSCs) with similar characteristics can successfully differentiate into chondrocytes, adipocytes, osteo- blasts, myocytes, and neuronal linage [15–17]. In addition, com- pared to BMSCs, a higher proportion of ADSCs express nestin which is a marker of progenitor neural cells [18]. Several bioactive protein factors secreted by ADSCs have been identified [19]. ADSCs secrete a range of growth factors whose levels achieved in culture provided significant protection to neurons [20–23]. Zhao et al. re- ported that ADSCs possessed potent neuroprotective activity against neuronal excitotoxicity [24]. The protective effect of ADSCs was found to be highly dependent on the presence of brain-derived neurotrophic factor (BDNF), an important neurotrophic factor which prevents neuronal degeneration and is involved in neuronal development [25]. Moreover, conditioned media of MSCs culture have induced neuritogenesis in PC12 cells as well as neuroprotective effects against neurotoxicity agents via neurotrophin contains [24–26]. 0006-291X/$ - see front matter Ó 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.bbrc.2013.09.069 ⇑ Corresponding author. Fax: +98 311 792 2517. E-mail address: razavi@med.mui.ac.ir (S. Razavi). Biochemical and Biophysical Research Communications 440 (2013) 381–387 Contents lists available at ScienceDirect Biochemical and Biophysical Research Communications journal homepage: www.elsevier.com/locate/ybbrc