drfeely.com/app/(pages)/articles/(content)/neural-biological-mechanisms/page.tsx

456 lines
20 KiB
TypeScript
Raw Normal View History

2023-08-27 01:54:00 +00:00
import Article from "@/components/Article";
import { Metadata } from "next";
export const metadata: Metadata = {
title: "Article - Neural Biological Mechanisms | Dr. Feely",
authors: [{ name: "Richard A. Feely, D.O., FAAO, FCA, FAAMA" }],
description: `The goal of this article is to provide the clinician with
information and knowledge of known biological mechanisms involved in somatic
dysfunction.`,
};
2023-08-27 01:54:00 +00:00
const ArticleNeuralBiologicalMechanisms = () => {
return (
<Article
title="Neural Biological Mechanisms"
author="Richard A. Feely, D.O., FAAO, FCA, FAAMA"
>
<p>
The goal of this article is to provide the clinician with information
and knowledge of known biological mechanisms involved in somatic
dysfunction.
</p>
<p>The reader will have the ability to describe:</p>
<ul>
<li>
The neural endocrine-immune network and its relationship to somatic
dysfunction
</li>
<li>How somatic dysfunction is endocrine-controlled and maintained</li>
<li>
Some of the known mechanisms of how somatic dysfunction is altered
biomechanically, biochemically, and bioenergetically
</li>
</ul>
<p>
The human body is a complex interdependent relationship of structure,
function, and mind. The body possesses complex homeostatic mechanisms
that maintain equilibrium for self-regulation and self-healing. These
homeostatic mechanisms represent an integrated network of messenger
molecules produced by cells in neural, endocrine, and immune systems.
Their signal coding and messenger molecules communicate through receptor
complexes located on cell membranes. The critical role of the nervous
system, especially the lymphatic, forebrain, and hypothalamus,
influences the output of the endocrine and immune systems.
</p>
<h2>Traditionally, the Immune and Nervous Systems</h2>
<p>
Traditionally, the immune and nervous systems were considered separate
and independent, each with its own cell types, cell functions, and
intercellular regulators. Altered function in each system was related to
the disease considered specific to that system. We now recognize not
only the interdependence and interlocking molecular organization but
also their extensive integration with the endocrine system. The
conceptual separations between the neural endocrine immune system
concerning structure, function, and communication have been discarded.
In their stead is a combination of multiple dimensional network
contributing to the functional unity of the body.
</p>
<p>
Today, we recognize this multifactorial nature is a result of the
following interactions of genetic, endocrine, nervous, immune, and
behavioral-emotional systems. This complex bi-directional interaction
occurs within the neural-endocrine-immune network. This network forms
the prime defense against disease and is responsible for the resistance
of infectious disease as well as cancer. The sensory information from
external and internal sources is tightly integrated with cognitive and
emotional processes which influence their neural endocrine immune
network through the hypothalamic-pituitary-adrenal axis.
</p>
<h2>Messengers</h2>
<p>
The basis for communication in the neural-endocrine-immune system is the
numerous messenger molecules that are released in the extracellular
fluid. These signal codes are small peptides, glycoproteins, amines, and
steroids. They express their activity through autocrine
(self-stimulating), paracrine (stimulates local tissue), synaptic, and
hormonal activity.
</p>
<h2>The Endocrine System</h2>
<p>
The endocrine system is described as using blood-borne messengers
operating over long distances by humoral transport. The neural system is
described as using chemical transmitters released into the neural
synaptic cleft, separating the pre and post-synaptic specialized nerve
cells. These common cellular mechanisms are bi-directional in
communication. Their similar molecular structure of many of the
messengers and the receptors are combined to transcend the traditional
borders that separate the neural, endocrine, and immune systems over the
years.
</p>
<p>
Monitoring the concentration of many of these extracellular messengers.
The central nervous system, particularly the limbic system and
hypothalamus, directly modulates the activity of the autonomic nervous
system and the endocrine systems. See The Network. Both of these systems
have extensive communication with the immune systems, thereby regulating
it under neural modulation as well. This combined action is
multi-dimensional and creates a compensatory reserve that enables the
body to mount an adaptive response to stressful conditions regardless of
their origin whether somatic, visceral, or psychogenic.
</p>
<h2>Stimuli-Somatic</h2>
<p>
Somatic, visceral, and emotional stimuli act as drivers capable of
influencing the activity via the hypothalamus, the spinal cord,
pituitary, to the autonomic nervous system, endocrine system, and immune
system, causing the general adaptive response. Noxious somatic stimuli
initiate protective reflexes providing the central nervous system with
warning signs. They influence the release of extracellular messengers
from the endocrine immune access system just described.
</p>
<p>
When activated by noxious stimuli such as rises from somatic
dysfunction, small capillary primary afferent fibers called alpha-gam
lambda and C-fibers, a-C-fibers or collectively referred to as (B
afferent system) from peripheral nociceptor endings, release neural
peptides such as substance P into the surrounding tissue thereby
initiating neurogenic inflammation.
</p>
<p>
The B afferent fibers systems represent a small subset of small
capillary primary afferent fibers with high threshold for activation
that are present in both somatic and visceral tissue. Central processes
of these fibers stimulate cells in the dorsal horn of the spinal cord.
Within the dorsal horn, the cells responding to the nociceptive input
initiate signals carried to the motor nuclei of the ventral horn to
alter the tonal muscles innervated by that particular spinal segment and
through the anterior lateral tract of the spinal cord which communicates
with the brain stem and the hypothalamus.
</p>
<p>
A significant result of the nociceptive input is increased activity in
the hypothalamic-pituitary-adrenal axis culminating in increased output
of norepinephrine from the sympathetic nervous system. This reflex can
be blocked by selectively eliminating the small capillary primary
afferent fibers. Capsaicin reduces the level of substance P in the
peripheral nervous system by destroying the small caliber primary
afferent fibers. This diminishes the hypothalamic response and reduces
the pituitary adrenal and autonomic responses to somatic stressors. The
neural-endocrine-immune network is affected by the output of the signals
from somatic dysfunction by initiating a compensatory shift in
extracellular messengers that then alters the function of the immune
system.
</p>
<p>
Collins and Strauss found that modulation of the sympathetic nervous
system plays an integral part in somatic pain and is a principal
mechanism of acupuncture's action. The control of somatic sympathetic
2023-08-27 01:54:00 +00:00
vasomotor activity before and after the placement of acupuncture needles
resulted in pain relief by reducing sympathetic vasomotor activity.
</p>
<p>
Nakamura, et al. found that afferent pathways of diskogenic low back
pain are transmitted mainly by sympathetic afferent fibers in the L2
nerve root and after needle injection, pain dissipated.
</p>
<h2>Stimuli-Visceral</h2>
<p>
The visceral factors in the cervical, thoracic, abdominal, and pelvic
areas, as well as peripheral blood vessels, communicate with the brain
stem and spinal cord through an extensive complement of afferent fibers
also considered part of the B afferent system. The visceral afferent
fibers reach their target organs by coursing in the same nerves as the
efferent autonomic fibers. They follow the routes of the vascular
system. The visceral sensory fibers, typically small caliber and having
little or no myelin, have cell bodies located in the thoraco-lumbar
dorsal root ganglia and in ganglia of several cranial nerves. These
central processes, neurons, terminate in the superficial and deep
regions of the dorsal horn of the spinal cord.
</p>
<p>
Spinal trigeminal nucleus and solitary nucleus of the vagus. The
thoraco-abdominal and pelvic organs have extensive sensory innervations.
These afferent fibers travel to the central nervous system with efferent
autonomic fibers. These sensory fibers traveling in the parasympathetic
nerves such as the vagus carry non-noxious information for reflex
control of the organ. Those traveling with the sympathetic nerves such
as the greater splanchnic carry noxious information packets.
</p>
<p>
The neurons of the deeper portions of the dorsal horn receive extensive
convergence of information from the small caliber sensory axons arising
in both visceral and somatic sources.
</p>
<p>
A similar convergence of somatic and visceral input is seen in the
solitary nucleus of the vagus. Neurons responsive to both visceral and
somatic nociceptive stimuli are located in the spinal cord, brain stem,
hypothalamus, and thalamus. These dual response neurons provide an
explanation for the phenomenon of referred pain between visceral and
somatic sources.
</p>
<h2>Stimuli-Emotional</h2>
<p>
The emotional factors of the human effecting the neural endocrine immune
network arise largely from the limbic forebrain system and hypothalamus.
The major components of the limbic forebrain include large portions of
associated neocortex, which include the prefrontal area, the cingulate
cortex, the insular cortex, and the inferior medial aspect of the
temporal lobe. Hippocampal formation and the amygdala receive extensive
connections from the frontal parietal and cingulate associational areas
of the neocortex and in turn project to the hypothalamus from the fornix
and striaterminalis, influencing the hypophyseotropic and hypothalamic
nuclei.
</p>
<p>
This limbic forebrain areas exert considerable influence over the
pituitary gland as well as the autonomic nervous system affecting growth
hormone, ACTH, prolactin, and somatostatin. The limbic system also
increases the sympathetic output from the spinal cord. These alterations
in the neural-endocrine activity affect the metabolic processes of the
body, shifting peripheral tissue to a catabolic form of metabolism,
leading to marked changes in the function of the immune system,
including stress-induced suppression of immune function. These
conditions characterize the general adaptive response in life.
</p>
<p>
Highly stressful circumstances in life significantly alter the status of
the immune system. This can include the death of a loved one, caring for
a family member with chronic progressive disease, summer vacation,
change in lifestyle, divorce, new job, etc.
</p>
<p>
The regulation of the neural-endocrine-immune network increases
susceptibility to various disease states. Overproduction or
underproduction of extracellular messages in response to either external
or internal stimuli or as a secondary response to other
disease-dysfunctional processes result in dysfunction of many aspects of
the network. The aging process also alters the regulation of the network
and is associated with various disease-dysfunctional states.
</p>
<p>
Lundberg showed that psychosocial factors significantly associated with
back pain and shoulder problems were related to psychophysiological
stress levels, i.e., high psychophysiological stress levels and low work
satisfaction.
</p>
<p>
He also found that mental and physical stress was found to increase
physiological stress levels and muscular tension and that mental stress
is of importance for the development of musculoskeletal symptoms and
pain. In addition, mental stress is not only induced by high demands but
also by demands that are too low which happens in many repetitive and
monotonous work situations. Interestingly enough, women are more prone
than men to have somatic complaints with repetition and monotonous work.
</p>
<h2>The Network</h2>
<p>
<strong>SELECTED NEURAL REGULATORS</strong>
</p>
<ul>
<li>Catecholamines: Dopamine, Norepinephrine</li>
<li>Cholines: Acetylcholine</li>
<li>Indolamines: Serotonin</li>
<li>
Peptides: Substance P, Neuropeptide Y, Calcitonin gene-related,
Polypeptide, Enkaphalins, Endorphins, Neurotensin, Cholecystokinin,
Angiotensin II, Vasoactive intestinal polypeptide, Bombesin,
Adrenocorticotropin, Somatostatin, Corticotropin
</li>
<li>Amino Acids: Glutamate, Aspartate, GABA, Glycine</li>
<li>Dynorphin, Histamine</li>
<li>Purines: Adenosine</li>
</ul>
<h2>CELL TYPES OF THE IMMUNE SYSTEM</h2>
<ul>
<li>Thymocytes: Lymphoid Cells of the thymus</li>
<li>
T-Cells: Lymphoid cells that mature in the thymus & express the T-cell
receptor (TCR)
</li>
<li>
Helper T-Cells: Lymphoid cells responding to cell surface antigens by
secreting cytokines
</li>
<li>
Cytotoxic T-Cells: Lymphoid cells responding to the cell surface
antigens by lysing cell producing the antigen
</li>
<li>
B-Cells: Lymphoid cells that, when activated, are capable of producing
immunoglobulins
</li>
<li>
Natural Killer Cells: Lymphoid cells capable of killing tumor cells
and virus/infected cells
</li>
<li>
Neutrophils: Major Lymphoid cell of the acute inflammatory response
and effector cells of humoral immunity
</li>
<li>
Basophils: Effector cells of IgE-mediated immunity that secrete
histamine granules in response to IgE activation
</li>
<li>
Eosinophils: Lymphoid cells containing lysosomal granules that can
destroy parasites
</li>
</ul>
<h2>NON-LYMPHOID CELL TYPES</h2>
<ul>
<li>
Fibroblast: Connective tissue cell capable of secreting and
maintaining the collagenous fiber matrix
</li>
<li>
Endothelial Cell: Squamous cell lining of the inner aspect of the
vascular system
</li>
<li>
Mesangial Cells: Specialized mesenchymal cells found in the renal
glomerulus
</li>
<li>
Chromaffin Cell: Neural peptides secreting cell found in the adrenal
medulla
</li>
<li>
Enterochromaffin Cell: Neural peptides secreting cell found in the
lining of the gastrointestinal system
</li>
<li>
Hepatocyte Liver Cell: Liver cell capable of secreting the acute phase
proteins
</li>
<li>
Endometrial Cell: Epithelial cell lining the inner surface of the
uterus
</li>
<li>
Astrocyte: Neuroglial cell found in the central nervous system
involved in forming the blood-brain barrier
</li>
<li>
Oligodendrocyte: Neuroglial cell forming myelin sheath around axons in
the central nervous system
</li>
<li>
Osteoblast: Specialized mesenchymal cells capable of secreting the
osteomatrix for the formation of bones
</li>
<li>
Osteophyte: Connective tissue cell found in bone representing a mature
form of osteoblast
</li>
<li>
Reticular Cell: Endodermal cell creating a three-dimensional network
for lymphocytes in the thymus, spleen, and lymph nodes
</li>
</ul>
<h2>IMMUNOREGULATORS</h2>
<ul>
<li>Interleukins 1-7</li>
<li>Interferons alpha, beta, and gamma</li>
<li>Tumor necrosis factor, beta</li>
<li>Colony-stimulating factors:</li>
<ul>
<li>Granulocyte-stimulating factor</li>
<li>Macrophage-stimulating factor</li>
<li>Granulocyte macrophage-stimulating factor</li>
<li>Interleukin III</li>
<li>Leukemia inhibiting factor or neuroleukin</li>
</ul>
<li>Transforming factor, beta</li>
</ul>
<h2>
ENDOCRINE SUBSTANCES KNOWN TO INTERACT WITH THE NEURAL AND IMMUNE
SYSTEMS
</h2>
<ul>
<li>Pituitary</li>
<ul>
<li>Adrenal Corticotrophin-ACTH</li>
<li>Thyrotrophin-TSH</li>
<li>Growth hormone releasing factor-GRH</li>
<li>Somatostatin-SS-SS</li>
<li>Prolactin</li>
</ul>
<li>Adrenal Medullary Hormones</li>
<ul>
<li>Epinephrine</li>
<li>Norepinephrine</li>
</ul>
<li>Adrenal Cortical Hormones</li>
<ul>
<li>Cortisol</li>
<li>Corticosterone</li>
<li>Aldosterone</li>
</ul>
<li>Thyroid Hormones</li>
<ul>
<li>Thyroxine</li>
<li>Triiodothyronine</li>
</ul>
<li>Growth Hormones</li>
<ul>
<li>Somatotropin</li>
<li>Somatomammotropin</li>
<li>Somatomedin</li>
</ul>
<li>Thymus</li>
<ul>
<li>Thymulin</li>
<li>Thymosin</li>
<li>Thymopoietin</li>
<li>Thalmic factor X</li>
</ul>
<li>Others</li>
<ul>
<li>Estrogen</li>
<li>Testosterone</li>
<li>Insulin</li>
</ul>
</ul>
<h2>References</h2>
<ul>
<li>
Beal, Myron, D.O., FAAO, 1995-96 Yearbook, Osteopathic Vision,
American Academy of Osteopathy, 1996.
</li>
<li>
A.A. Buerger, Ph.D., Philip E. Greenman, D.O., Empirical Approaches to
the Validation of Spinal Manipulation, 1985, published by Charles C.
Thomas.
</li>
<li>
D. Thomas Collins, S. Strauss, Somatic Sympathetic Vasomotor Changes
Documented by Medical Thermographic Imaging During Acupuncture
Analgesia, Clinical Rheumatology, 1992, 55-59.
</li>
<li>
Richard G. Gillette, Ronald C. Kramis, William J. Roberts,
Sympathetic activation of cat spinal neurons responsive to noxious
stimulation of deep tissues in the low back, Pain , 1994, 56, 31-42.
</li>
<li>
Ulf Lundberg, Methods and application of stress research,
Technology and Health Care, 1995, 3-9.
</li>
<li>
Shin-Ichiro Nakamura, Kazuhisa Takahasi, Yuzuru Takahashi, Masatsune
Yamagata, Hideshige Moriya, The Afferent Pathways of Discogenic Low
Back Pain, Bone and Joint Surgery, 1996, July; 78/B, 606-612.
</li>
<li>
Robert C. Ward, Foundations for Osteopathic Medicine, American
Osteopathic Association, 1997; Williams & Wilkins
</li>
</ul>
</Article>
);
};
export default ArticleNeuralBiologicalMechanisms;