Elsevier

Medical Hypotheses

Volume 75, Issue 2, August 2010, Pages 162-168
Medical Hypotheses

Multifunctional Merkel cells: Their roles in electromagnetic reception, finger-print formation, Reiki, epigenetic inheritance and hair form

https://doi.org/10.1016/j.mehy.2010.02.011Get rights and content

Summary

Merkel cells are located in glabrous and hairy skin and in some mucosa. They are characterized by dense-core secretory granules and cytoskeletal filaments. They are attached to neighboring keratinocytes by desmosomes and contain melanosomes similar to keratinocytes. They are excitable cells in close contact with sensory nerve endings but their function is still unclear. In this review, following roles are attributed for the first time to the Merkel cells: (1) melanosomes in Merkel cells may be involved in mammalian magnetoreception. In this model melanosome as a biological magnetite is connected by cytoskeletal filaments to mechanically gated ion channels embedded in the Merkel cell membrane. The movement of melanosome with the changing electromagnetic field may open ion channels directly producing a receptor potential that can be transmitted to brain via sensory neurons. (2) Merkel cells may be involved in finger-print formation: Merkel cells in glabrous skin are located at the base of the epidermal ridges the type of which defines the finger-print pattern. Finger-print formation starts at the 10th week of pregnancy after the arrival of Merkel cells. Keratinocyte proliferation and the buckling process observed in the basal layer of epidermis resulting in the epidermal ridges may be controlled and formed by Merkel cells. (3) Brain–Merkel cell connection is bi-directional and Merkel cells not only absorb but also radiate the electromagnetic frequencies. Hence, efferent aspects of the palmar and plantar Merkel nerve endings may form the basis of the biofield modalities such as Reiki, therapeutic touch and telekinesis. (4) Adaptive geographic variations such as skin color, craniofacial morphology and hair form result from interactions between environmental factors and epigenetic inheritance system. While environmental factors produce modifications in the body, they simultaneously induce epigenetic modifications in the oocytes and in this way adaptive changes could be passed onto the next generations. Merkel cells are multisensorial cells that can receive almost all environmental stimuli including electromagnetic and ultraviolet radiations, temperature, humidity and food type and they seem to transfer the environmental information to oocytes by affecting nuclear receptors in oocytes. (5) Hair form is categorized as straight, wavy and spiral. Merkel cells found at the bulge region of hair follicles may determine the hair form with their different paracrine secretions related to hair cycle producing variations between populations. In conclusion, Merkel cells are multifunctional cells which may close the gap between orthodox medicine and complementary medicine such as acupuncture and Reiki.

Introduction

Merkel cells are neuroendocrine cells found in hairy skin, glabrous skin, and ectoderm-derived mucosa such as mouth, lips and nose [1]. In glabrous skin, Merkel cells are always located on the epidermal ridges in close contact with myelinated nerve fibers [2]. In hair follicles, Merkel cells are located in the bulge, an area that corresponds to the reservoir of stem cells, and are rarely associated with nerve endings [3]. In hairy skin, Merkel cells are found in thickened parts of the epidermis between hair follicles, the so-called “touch dome” [4]. Various nerve fibers innervate Merkel cells within the touch dome, but stimulation of touch domes housing Merkel cells does not produce a conscious sensation [5]. Merkel cells also exist in the epithelia of oral and nasal mucosa but some of them are not connected to nerve fibers and play a role within the epithelium as isolated cells [6]. Merkel cells are linked to adjacent keratinocytes by desmosomes and attached to the basement membrane by hemidesmosomes [3]. Microvilli are present on the cell surface and interdigitate with the surrounding epidermal cells [2]. Furthermore, melanosomes have been described inside the cytoplasm of Merkel cells [7]. Their cytoplasm also contains a cytoskeleton of intermediate filaments (cytokeratin CK20) that are more loosely distributed than in keratinocytes and extend into spine-like protrusions [8].

Merkel cells synthesize numerous neuropeptides contained in dense-core secretory granules located in the cytoplasm apposed to the nerve terminals [1]. After stimulation of the Merkel cells, dense-core granules release their neuropeptides by classical exocytosis, but the stimulation required for this phenomenon has not been clearly identified [9]. The peptides presumably act as neurotransmitters, neuromodulators, or mediators, acting on sensory nerve endings and serving either a trophic role on keratinocytes or some unknown endocrine function [1]. Both Merkel cells and neurons are excitable cells, but the information that may be transmitted has not been clearly elucidated [10]. Merkel cell–neurite complexes and their localization in touch-sensitive areas led to the suggestion that they are mechanoreceptors [11], but studies disagree about the dependence of epidermal touch sensitivity on Merkel cells [12]. While the structure of the Merkel cell is well established, their function is still unclear. The numerous peptides they synthesize and release may allow them to communicate with many cells other than neurons, and they may play an important role in human physiology and biology. The purpose of the present review is to shed light on the possible functions of these least-known cells of the skin.

Section snippets

Role of Merkel cells in electromagnetic reception

Many animals have a magnetic sense which they may use in navigation, but almost nothing is known of the detailed cellular structures and processes by which magnetic fields are detected and encoded by receptor cells for transmission to the brain [13]. The discovery that crystals of the mineral magnetite (Fe3O4) underlie the ability of magnetotactic bacteria to swim along magnetic field lines [14] inspired searches for magnetite in diverse animals. Magnetite particles suitable for use in magnetic

Role of Merkel cells in finger-print formation

On the palmar surfaces of the hands and plantar surfaces of the feet there are numerous fine epidermal ridges which form regular but complex patterns called fingerprints. Finger-print patterns are encoded at the interface between dermis and epidermis, therefore the pattern cannot be destroyed by superficial skin injuries [40]. Although most fingerprints can be classified as one of three types – arches, loops, or whorls – there is great individual variation in detail, so great indeed that no two

Role of Merkel cells in biofield modalities such as Reiki, therapeutic touch and telekinesis

While specific frequencies of electromagnetic radiation can be absorbed by the body, electromagnetic fields are also produced in the body due to movement or rotation of charged particles such as protons, electrons and ions [45]. So the humans not only absorb but also radiate the electromagnetic frequencies [46]. Biofield therapies such as therapeutic touch (hands-off) and Reiki (hands-on therapies) which have been used to reduce pain, facilitate healing and promote health claim to base their

In utero functions of Merkel cells

Human fetal adrenal development is characterized by rapid growth, high steroidogenic activity, and a distinct morphology, including a unique cortical compartment known as the fetal adrenal cortex. For most of gestation, the predominant fetal zone accounts for 80–90% of the cortical volume and is the primary site of growth and steroidogenesis, producing 100–200 mg/day of the androgenic steroid, dehydroepiandrosterone sulfate (DHEA-S) [57]. We previously published our hypothesis about dependence

Role of Merkel cells in epigenetic inheritance and biological adaptation

All human groups of present-day are adapted to their ecological niche in various ways. As a result of adaptation, there is a great deal of variation from one geographic region to another in skin color, hair form, craniofacial morphology, stature, body proportions, and a host of less immediately obvious traits [65]. The term adaptation is therefore interpreted to encompass those responses in the phenotype, which are produced by the action of the environment upon a given gene system, and is

Role of Merkel cells in hair form and skin biology

Hair form is an important structure that has enabled man to adapt to life in diverse environmental conditions [69]. Humans who reside in cold climates tend to have straight hair; inhabitants of more moderate climates have wavy hair, and those from hot humid climates have tightly coiled, spiraled, wool-like hair. Tightly coiled spiraled hair tends to facilitate the removal of the heat from the scalp and cooling of the brain while straight hair promotes conservation of heat and warming of the

Conflicts of interest statement

None declared.

Acknowledgments

I dedicate this work to my parents Fatma and Ferhat Irmak and to my wife Zisan Irmak.

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