The human brain and its neural stem cells postmortem: from dead brains to live therapy

Cadaveric Adipose-Derived Stem Cells for Regenerative Medicine and Research

Advances in regenerative medicine have enabled the search for new solutions to current health problems in so far unexplored fields. Thus, we focused on cadaveric subcutaneous fat as a promising source of adipose-derived stem cells (ADSCs) that have potential to differentiate into different cell lines. With this aim, we isolated and characterized ADSCs from cadaveric samples with a postmortem interval ranging from 30 to 55 h and evaluated their ability to differentiate into chondrocytes or osteocytes. A commercial ADSC line was used as reference. Morphological and protein expression analyses were used to confirm the final stage of differentiation. Eight out of fourteen samples from patients were suitable to complete the whole protocol. Cadaveric ADSCs exhibited features of stem cells based upon several markers: CD29 (84.49 ± 14.07%), CD105 (94.38 ± 2.09%), and CD44 (99.77 ± 0.32%). The multiparametric assessment of differentiation confirmed the generation of stable lines of chondrocytes and osteocytes. In conclusion, we provide evidence supporting the feasibility of obtaining viable postmortem human subcutaneous fat ADSCs with potential application in tissue engineering and research fields.

Plausible Role of Stem Cell Types for Treating and Understanding the Pathophysiology of Depression

Major Depressive Disorder (MDD), colloquially known as depression, is a debilitating condition affecting an estimated 3.8% of the population globally, of which 5.0% are adults and 5.7% are above the age of 60. MDD is differentiated from common mood changes and short-lived emotional responses due to subtle alterations in gray and white matter, including the frontal lobe, hippocampus, temporal lobe, thalamus, striatum, and amygdala. It can be detrimental to a person’s overall health if it occurs with moderate or severe intensity. It can render a person suffering terribly to perform inadequately in their personal, professional, and social lives. Depression, at its peak, can lead to suicidal thoughts and ideation. Antidepressants manage clinical depression and function by modulating the serotonin, norepinephrine, and dopamine neurotransmitter levels in the brain. Patients with MDD positively respond to antidepressants, but 10–30% do not recuperate or have a partial response accompanied by poor life quality, suicidal ideation, self-injurious behavior, and an increased relapse rate. Recent research shows that mesenchymal stem cells and iPSCs may be responsible for lowering depression by producing more neurons with increased cortical connections. This narrative review discusses the plausible functions of various stem cell types in treating and understanding depression pathophysiology.

Mary Jane Hogue (1883-1962): A pioneer in human brain tissue culture

The ability to maintain human brain explants in tissue culture was a critical step in the use of these cells for the study of central nervous system disorders. Ross G. Harrison (1870-1959) was the first to successfully maintain frog medullary tissue in culture in 1907, but it took another 38 years before successful culture of human brain tissue was accomplished. One of the pioneers in this achievement was Mary Jane Hogue (1883-1962). Hogue was born into a Quaker family in 1883 in West Chester, Pennsylvania, and received her undergraduate degree from Goucher College in Baltimore, Maryland. Research with the developmental biologist Theodor Boveri (1862-1915) in Würzburg, Germany, resulted in her Ph.D. (1909). Hogue transitioned from studying protozoa to the culture of human brain tissue in the 1940s and 1950s, when she was one of the first to culture cells from human fetal, infant, and adult brain explants. We review Hogue's pioneering contributions to the study of human brain cells in culture, her putative identification of progenitor neuroblast and/or glioblast cells, and her use of the cultures to study the cytopathogenic effects of poliovirus. We also put Hogue's work in perspective by discussing how other women pioneers in tissue culture influenced Hogue and her research.

Long live the stem cell: the use of stem cells isolated from post mortem tissues for translational strategies

The "stem cell" has become arguably one of the most important biological tools in the arsenal of translational research directed at regeneration and repair. It remains to be seen whether every tissue has its own stem cell niche, although relatively recently a large amount of research has focused on isolating and characterizing tissue-specific stem cell populations, as well as those that are able to be directed to transdifferentiate into a variety of different lineages. Traditionally, stem cells are isolated from the viable tissue of embryonic, fetal, or adult living hosts; from "fresh" donated tissues that have been surgically or otherwise removed (biopsies), or obtained directly from tissues within minutes to several hours post mortem (PM). These human progenitor/stem cell sources remain potentially highly controversial, since they are accompanied by various still-unresolved ethical, social, moral and legal challenges. Due to the limited number of "live" donors, the small amount of material obtained from biopsies and difficulties during purification processes, harvesting from cadaveric material presents itself as an alternative strategy that could provide a hitherto untapped source of stem cells. However, PM stem cells are not without their own unique set of limitations including difficulty of obtaining samples, limited supply of material, variations in delay between death and sample collection, possible lack of medication history and suboptimal retrospective assignment of diagnostic and demographic data. This article is part of a Directed Issue entitled: Regenerative Medicine: The challenge of translation.

Current concept in neural regeneration research: NSCs isolation, characterization and transplantation in various neurodegenerative diseases and stroke: A review

Since last few years, an impressive amount of data has been generated regarding the basic in vitro and in vivo biology of neural stem cells (NSCs) and there is much far hope for the success in cell replacement therapies for several human neurodegenerative diseases and stroke. The discovery of adult neurogenesis (the endogenous production of new neurons) in the mammalian brain more than 40 years ago has resulted in a wealth of knowledge about stem cells biology in neuroscience research. Various studies have done in search of a suitable source for NSCs which could be used in animal models to understand the basic and transplantation biology before treating to human. The difficulties in isolating pure population of NSCs limit the study of neural stem behavior and factors that regulate them. Several studies on human fetal brain and spinal cord derived NSCs in animal models have shown some interesting results for cell replacement therapies in many neurodegenerative diseases and stroke models. Also the methods and conditions used for in vitro culture of these cells provide an important base for their applicability and specificity in a definite target of the disease. Various important developments and modifications have been made in stem cells research which is needed to be more specified and enrolment in clinical studies using advanced approaches. This review explains about the current perspectives and suitable sources for NSCs isolation, characterization, in vitro proliferation and their use in cell replacement therapies for the treatment of various neurodegenerative diseases and strokes.

Regulation of neural stem cell in the human SVZ by trophic and morphogenic factors

The subventricular zone (SVZ), lining the lateral ventricular system, is the largest germinal region in mammals. In there, neural stem cells express markers related to astoglial lineage that give rise to new neurons and oligodendrocytes in vivo. In the adult human brain, in vitro evidence has also shown that astrocytic cells isolated from the SVZ can generate new neurons and oligodendrocytes. These proliferative cells are strongly controlled by a number of signals and molecules that modulate, activate or repress the cell division, renewal, proliferation and fate of neural stem cells. In this review, we summarize the cellular composition of the adult human SVZ (hSVZ) and discuss the increasing evidence showing that some trophic modulators strongly control the function of neural stem cells in the SVZ.

Activation of subventricular zone stem cells after neuronal injury

The mammalian subventricular zone (SVZ) has garnered a tremendous amount of attention as a potential source of replacement cells for neuronal injury. This zone is highly neurogenic, harbours stem cells and supports long-distance migration. The general pattern of activation includes increased proliferation, neurogenesis and emigration towards the injury. Intrinsic transcription factors and environmental signalling molecules are rapidly being discovered that may facilitate the induction of these cells to mount appropriate therapeutic responses. The extent of SVZ neurogenesis in humans is controversial. However, tantalizing new data suggest that humans are capable of generating increased numbers of neurons after a variety of diseases.

Increase in clusterin-containing follicles in the adenohypophysis of drug abusers

The hypothalamic-pituitary-adrenocortical (HPA) system in drug abusers may be affected due to disorders of the hypothalamic dopaminergic system. The present study investigated alterations in the adenohypophysis of middle-aged drug abusers (40-60 years of age), using clusterin-containing mixed cell-follicles as the indicator, in which clusterin (apolipoprotein J) is a multifunctional glycoprotein related to neurodegeneration. The paraffin-embedded adenohypophyses of methamphetamine and psychotropic drug abusers (n = 76) were compared with those of non-abusers (n = 82). The number of follicles was larger in drug abusers independent of the immediate cause of death, although the size was not significantly different. When cell types forming the follicles were immunohistochemically examined, drug abusers showed an increase of prolactin (PRL) cells and gonadotroph cells and a reciprocal decrease of growth hormone cells, suggesting hypofunction of dopaminergic neurons in the hypothalamus, while there was no change in the adrenocorticotropic hormone and thyroid-stimulating hormone cells. These increases of the clusterin-containing follicles and PRL cells in the follicles may be related to the dysfunction of dopaminergic neurons in the hypothalamus of chronic drug abusers and may be useful for investigating drug abuse in forensic casework.

Hypoxic changes in Purkinje cells of the human cerebellum

The significance of both Purkinje cell numbers and various neuronal changes for the diagnosis and timing of hypoxic-induced brain lesions was investigated in tissue samples from the cerebellar cortex of 52 individuals with a history of acute or prolonged cerebral hypoxia/ischemia before death. Furthermore, the area of the Purkinje cell somata (PC size) was measured using an automatic image processing and analysis system (LEICA QWin). Significantly reduced numbers of Purkinje cells (<6 cells/unit length of 1 mm) and a decreased portion (<50%) of intact Purkinje cells could be detected in individuals with a period of resuscitation of at least 2 h after acute circulatory arrest. Average cell numbers of less than 4 cells/unit were found in individuals who suffered from diffuse brain swelling and were ventilated for at least 3 days, as well as in individuals who died of brain death. Moreover, the Purkinje cells in these cases exhibited shrunken somata compared to the controls. Specimens that were stored at room temperature up to 30 h after removal at autopsy showed no significant autolytic changes of the Purkinje cells. After 46 h, however, reduced Purkinje cell numbers and shrunken cell bodies were found.