Endothelial Cells in Co-culture Enhance Embryonic Stem Cell Differentiation to Pancreatic Progenitors and Insulin-Producing Cells through BMP Signaling

Endothelial cells (ECs) represent the major component of the embryonic pancreatic niche and play a key role in the differentiation of insulin-producing β cells in vivo. However, it is unknown if ECs promote such differentiation in vitro. We investigated whether interaction of ECs with mouse embryoid bodies (EBs) in culture promotes differentiation of pancreatic progenitors and insulin-producing cells and the mechanisms involved. We developed a co-culture system of mouse EBs and human microvascular ECs (HMECs). An increase in the expression of the pancreatic markers PDX-1, Ngn3, Nkx6.1, proinsulin, GLUT-2, and Ptf1a was observed at the interface between EBs and ECs (EB-EC). No expression of these markers was found at the periphery of EBs cultured without ECs or those co-cultured with mouse embryonic fibroblasts (MEFs). At EB-EC interface, proinsulin and Nkx6.1 positive cells co-expressed phospho-Smad1/5/8 (pSmad1/5/8). Therefore, EBs were treated with HMEC conditioned media (HMEC-CM) suspecting soluble factors involved in bone morphogenetic protein (BMP) pathway activation. Upregulation of PDX-1, Ngn3, Nkx6.1, insulin-1, insulin-2, amylin, SUR1, GKS, and amylase as well as down-regulation of SST were detected in treated EBs. In addition, higher expression of BMP-2/-4 and their receptor (BMPR1A) were also found in these EBs. Recombinant human BMP-2 (rhBMP-2) mimicked the effects of the HMEC-CM on EBs. Noggin (NOG), a BMP antagonist, partially inhibited these effects. These results indicate that the differentiation of EBs to pancreatic progenitors and insulin-producing cells can be enhanced by ECs in vitro and that BMP pathway activation is central to this process

Conventional and novel stem cell based therapies for androgenic alopecia

Dodanim Talavera-Adame,1 Daniella Newman,2 Nathan Newman1 1American Advanced Medical Corp. (Private Practice), Beverly Hills, CA, 2Western University of Health Sciences, Pomona, CA, USA Abstract: The prevalence of androgenic alopecia (AGA) increases with age and it affects both men and women. Patients diagnosed with AGA may experience decreased quality of life, depression, and feel self-conscious. There are a variety of therapeutic options ranging from prescription drugs to non-prescription medications. Currently, AGA involves an annual global market revenue of US$4 billion and a growth rate of 1.8%, indicating a growing consumer market. Although natural and synthetic ingredients can promote hair growth and, therefore, be useful to treat AGA, some of them have important adverse effects and unknown mechanisms of action that limit their use and benefits. Biologic factors that include signaling from stem cells, dermal papilla cells, and platelet-rich plasma are some of the current therapeutic agents being studied for hair restoration with milder side effects. However, most of the mechanisms exerted by these factors in hair restoration are still being researched. In this review, we analyze the therapeutic agents that have been used for AGA and emphasize the potential of new therapies based on advances in stem cell technologies and regenerative medicine. Keywords: stem cells, stem cell therapies, hair follicle, dermal papilla, androgenic alopecia, laser, hair regeneratio

New drugs under investigation for the treatment of alopecias

Introduction: Alopecia is a very common complaint in medical practice, which usually has a large psychological impact in patients. Treatment of alopecia is often difficult and frustrating for patients and clinicians owing to the slow growth rate of the hair, long treatment terms, limited efficacy, and possible adverse side effects. Areas covered: This paper reviews the new and emerging treatments for two of the most common forms of alopecia, known as androgenetic alopecia and alopecia areata. A literature search of PubMed/MEDLINE and ClinicalTrial.gov was performed to gather information about active research on new treatments for alopecias. Websites of companies sponsoring clinical trials were also searched for interim result data. Expert opinion: Many new therapies in two of the most common forms of hair loss have been developed and are currently being studied with encouraging results. In alopecia areata, JAK inhibitors are promising. The discovery of JAK inhibitors has prompted the research and identification of new molecules. In androgenetic alopecia, we are still looking for a topical treatment that is superior to topical minoxidil. However, stem-cell research is advancing and the goal to create new follicles or refresh dormant follicles may be realized in the near future. Trial registration: ClinicalTrials.gov identifier: NCT02299297. Trial registration: ClinicalTrials.gov identifier: NCT03570749. Trial registration: ClinicalTrials.gov identifier: NCT02974868. Trial registration: ClinicalTrials.gov identifier: NCT03137381. Trial registration: ClinicalTrials.gov identifier: NCT03594227. Trial registration: ClinicalTrials.gov identifier: NCT02553330. Trial registration: ClinicalTrials.gov identifier: NCT02561585. Trial registration: ClinicalTrials.gov identifier: NCT03315689. Trial registration: ClinicalTrials.gov identifier: NCT03354637. Trial registration: ClinicalTrials.gov identifier: NCT03651752. Trial registration: ClinicalTrials.gov identifier: NCT03532958. Trial registration: ClinicalTrials.gov identifier: NCT03359356. Trial registration: ClinicalTrials.gov identifier: NCT02018042. Trial registration: ClinicalTrials.gov identifier: NCT02684123. Trial registration: ClinicalTrials.gov identifier: NCT02684097