The Circadian Rhythm Key Factor in the Evolution of the Biosphere Volume 57- Issue 5

Bruno Riccardi¹* and Sergio Resta²

• ¹Biologist freelancer, 56022 Castelfranco di Sotto (Pisa), Via dei lazzeri, 33, Italy
• ²University of Rome “La Sapienza”, 53043 Chiusi (SI), Via Montegrappa, 1, Italy

Received: July 19, 2024; Published: July 31, 2024

*Corresponding author: Bruno Riccardi, Biologist freelancer, 56022 Castelfranco di Sotto (Pisa), Via dei lazzeri, 33, Italy

DOI: 10.26717/BJSTR.2024.57.009074

Abstract PDF

Our whole life is marked by the cosmic rhythm. For this reason, astrology is widely considered a source of inspiration for important decisions, and it is so popular that many people consult the horoscope before starting their daily activities. But believe it or not, Chronobiology has shown that all our vital activity follows biological rhythms and is subject to astral cycles. Not only we are made of the same matter that forms the stars, but we are subject and bound to their powerful influence in all biological activities too. The astral influence is so powerful that it affects the state of well-being and illness and even the response to therapies, based on the moment of their administration, as Chronotherapy has demonstrated. We are in all respects children of the stars, as the words of a well-known Italian song say. This article describes the cosmic rhythms of our solar system and the astronomical geodynamics of our planet and tries to explain what consequences they have produced on the environmental conditions that govern life in the Earth’s Biosphere. We are going to also try to explain why and what paths evolution has followed to shape living beings with the same matter of which the stars are made. However, we aren’t going to examine, except superficially, the more specifically biomolecular and genetic mechanisms that guide circadian rhythms, already widely described by other authors.

Introduction: We give the definition of the words cycle and rhythm, to grasp the differences in meaning they express, because they are often used improperly to express the same meaning.
The Rhythm: It is an ordered succession, from regular intervals of time, with which a phenomenon takes place, an organism develops. A Cycle is a succession over time of phenomena that are always repeated in the same way

Keywords: Solar System; Circadian Rhythm; Biological Evolution; Biosphere Environment Interaction; Chronobiology and Chronotherapy

All living beings contain the same molecular mechanism, product of evolution, which requires them to respect chronologically in the execution of fundamental biological activities. This is their internal biological clock. Its origin was the pivotal event that allowed living beings to obtain the best conditions to adapt to their environment. The Earth’s Geosphere is the cultivation ground, the food source that nourishes all living things present on its surface, the Biomass, and has imposed strict rules for their survival. So that every change in one must correspond to an adaptation in the other. It is the eternal and iron law that binds and drags the living to respect the cyclical geodynamic evolutions of the Earth. Life in the plant and animal kingdoms exists thanks to the mechanism of their internal biological clock that synchronizes them with the best survival conditions. This mechanism was given the name “circadian rhythm” because it marks the cycle of existence of all living beings.

What is the Circadian Rhythm and How Does it Work

The circadian rhythm, as it was conceived and described by Chronobiology, is the mechanism with which living organisms adapt to the cyclical change in the astral conditions to which the earth is subject. By definition and for the subjects involved, it is a phenomenon limited to planets where living beings are present, the only ones capable of modifying their state to adapt to their environment. Our planet is the only one in the entire universe that we know of, which has life forms with these capabilities [1-3]. In order to try to understand the circadian phenomenon it is necessary to make some assumptions. First of all we must describe the environment in which these phenomena occur and the cyclical variations to which it is subject, and then explain the mechanism thanks to which the living beings it hosts are able to adapt to it.

The Solar System, Where Everything Originates

Our solar system is the place of events, the environment in which the circadian rhythm takes shape. The solar system contains the earth with its Biosphere, together they form a complex organism that rotates around the sun on an orbit resulting from gravitational interactions with the other planets, and follows an approximately annual repetitive cycle. In its journey the earth goes through different phases with cyclical variations in its exposure with respect to the orientation of the sun’s rays [4]. Solar rays represent the Earth’s energy source, and its orientation with respect to solar rays is a fundamental factor of the circadian rhythm, it is the main physical cause that regulates the phenomenon as a whole [5]. Therefore it is precisely to these conditions that the Biosphere must adapt in order to survive. Let’s see how it works. The origin and evolution of the terrestrial biosphere was possible thanks to the presence of favorable environmental conditions [6,7].

Planet Earth is distinguished from all those we know by the presence of sunlight, water, atmosphere and temperature, in the optimal quality and quantity for the type of Biosphere it has produced. Consequently, there is an indissoluble link between the environment and resident organisms and it is essential that it is maintained to maintain global balance. Chronobiology studies the evolution of terrestrial geodynamics and the evolution of the Biosphere which must be synchronically in tune. The diachronic relationships between living things and cosmic events are crucial and at the basis of the evolutionary mechanism. The rigid synchronism between these events, described by Chronobiology, is so close as to determine the maintenance of the physiological homeostasis of living beings and their state of well-being. Research has highlighted in recent years the close link between the outcome of therapeutic treatments and the time of their administration too. The therapy that follows circadian rhythms was found to be more effective than traditional treatments, and from these experiences a new discipline was born, Chronotherapy.

The Balance of the Astral Cycles

The fundamental forces described by modern physics are responsible for natural phenomena, and are the primary causes that regulate all the events that occur in the universe and that gave rise to the stars and celestial bodies present in it. The state of dynamic equilibrium generated between gravitational forces can be conceived as an integrated communication system. On individual planets and on Earth, cosmic and gravitational mechanisms have modified the environmental conditions present there. Even the Earth and its Biosphere, since their origin, have established a synchronized interaction mechanism that maintains the overall dynamic balance (Figure 1).

Figure 1

The name Circadian Rhythm has been given to the adaptive mechanism of the Biosphere to the geodynamic conditions of the environment and their cyclical alternation. The prefix “circa” of the word Circadian expresses well the concept of approximation of the biological rhythm to the astral rhythm. In fact, the circadian rhythm that regulates the Biosphere is not exactly 24 hours, as is the case with the rhythm of our solar system, but is timed based on the metabolic and behavioral activities of individual living beings. So that the flow of the earth’s cyclical rhythms with the repetitive periodicities of their changes, mark the continuous diachronic changes of the Biosphere to maintain the mutual homeostatic balance.

The Origin of Life

The main difficulties that terrestrial organic matter had to overcome to give rise to ancestral life forms were [8]:

• Isolate organic matter from the general primordial magmatic chaos to begin its own evolutionary path; • Use the only energy and food sources available, solar and gravitational energy plus water and a few salts, to obtain energy • Ensure a mechanism for transforming the energy obtained into organic matter, maintaining its survival and transmitting it to future generations.

The first obstacle was resolved with the formation of a separation barrier between the organic matter environment and the surrounding one, the barrier was called the cell membrane; The second obstacle was overcome with the birth of a mechanism capable of exploiting solar energy, water and the few available salts to generate organic matter: the photosynthesis mechanism. The photosynthetic mechanism is strongly dependent on sunlight and the cyclic variations it goes through. Finally, the transmission of life to future generations was achieved with the acquisition of a code containing the essential information of every living thing, the genetic code. The ancestral organism that first formed then differentiated over millions of years into the current living forms that populate the earth [9-11]. Thus all living forms have inherited a cell membrane, a genetic code and the constraint of dependence on the cyclic variations of sunlight, cyclic variations which will later be called Circadian Rhythm.

Biofeedback Basic Mechanism of the Circadian Rhythm

Biofeedback is the automatic response mechanism implemented by biological systems to adapt appropriately and consistently to the environmental stimuli received. This “retroactive” interaction system also allows living beings to obtain information relating to the adequacy of their physiological responses to the stimuli received in a rapid, accurate and synchronous way. It is an essential mechanism present in all living things, from bacteria to humans.

It is based on interaction/communication and exchange of useful information so that a biological system can satisfy the following conditions to maintain balance:

• It must have an electrophysiological potential in the membranes or cell walls (membrane potential) to be able to respond in real time to external stimuli. • Requires the presence of a complex feedback system capable of detecting environmental variations and translating them into adaptive modifications of metabolic activity. The two conditions must work in unison and in sync with each other. What energy powers the two systems? Energy is produced by the difference in the electrochemical gradient between the inside and outside of the cell membranes and by the maintenance of their repetitive dynamic equilibrium. The receptor complexes that form the feedback system must be able to respond to stimuli of different nature: essentially these are mechanical stimuli (frequencies of molecular vibrations) and electromagnetic stimuli (light and heat), so that the system can adapt metabolic activities.

Communication is the Cornerstone of Evolution

Communication is the key mechanism by which the interaction between the elementary particles that form matter in all its forms and expressions and their environment occurs and conditions their formation and evolution. The high level of organization and complexity of the Biosphere has undergone significant changes over very long periods of time, measurable in geological eras, and throughout this period the Sun has continued to transmit its radiation to the surface of our planet [12]. The Earth’s Biosphere is the complex system formed by living organisms that can exchange matter between themselves and their environment. Our planet, from a thermodynamic point of view, is isolated from the outside and exchanges of matter are absent, therefore it follows Lavoisier’s rule “nothing is created and nothing is destroyed, everything is transformed”. Only rarely does it receive a supply of matter from the outside, from meteors and meteorites. Therefore, within the Biosphere there is a constant cyclical flow of energy and matter. The main source of terrestrial energy comes from the Sun and is transformed by biological systems and environmental factors into organic matter that ensures the maintenance of life as we know it.

The system formed by the Biosphere - Environment interaction called Ecosystem is an interactive and balanced dynamic system, in which biological rhythms are produced, as a result of the geodynamic forces in play, which are the independent variables that condition the entire system. The Biosphere can only transform the conditions existing in its Habitat, but cannot change the conditions of atmospheric and geophysical events. This is what happened until the advent of the industrial revolution. Cause the industrial production, man has completely distorted climatic conditions, consequently modifying the rhythm of biological events. How do Biosphere-Environment communicate with each other and how do they maintain their balance? They communicate through physical contact, direct or indirect, however mediated by a transmissible and mutually recognizable mechanism. According to modern physics, this means of interaction is produced by mechanical, electromagnetic or gravitational waves and through the matter they possibly transport. These waves have a high informational content expressed by the modulable dimensions they can take on: their length, amplitude and frequency to which is added, in electromagnetic waves, the energy of the particles they transport in the form of electric charge. Thus a universal code connects all the organic and inorganic matter present in the universe.

Communication Between Biosphere and Environment

In order to maintain their mutual interaction, the environment and living things must communicate with each other. The ability to interact is conditioned by the properties of the receptor systems of living things. These systems are made up of molecular complexes of a protein nature that regulate the passage of ions with the variation of their conformational state caused by the specific stimuli they receive. They are divided into: Mechanoreceptors, Thermoreceptors, Chemoreceptors, Photoreceptors, etc. (Figure 2). Ultimately the entire communication system, from the single-cell level to complex neuronal networks, is determined by the quantity and quality of the receptor systems, the feedback systems and their distribution on the cell membranes. This transmission mechanism is extremely sophisticated and effective, and is essential for keeping all elements of the system in contact. In fact, it has been universally adopted in all living organisms, and is encoded in their genetic heritage [13].

Figure 2

The variation produced in the protein conformation of the sense organs is subsequently transmitted to the intracellular biological system, which can thus modulate its internal organization to adapt it to the environmental conditions that stimulated it (Figure 3). The known receptor systems respond to the frequency modulations of the stimuli they receive, the effective response is obtained when the wave stimulus and the receptor come into harmony or, according to the expression of quantum mechanics, when they enter “in resonance”. In the relationship between the Biosphere and the Environment, the latter has had predominance over the organisms present in it, since it is responsible for the astral and climatic conditions to which living things must necessarily adapt (Figure 1). Since the conditions of the environmental factors that cause adaptive transformations in the Biosphere are decisive, we must examine how these factors have transformed over the millions of years of life of our planet.

Figure 3

Among the Environmental Factors to Consider are for Example: Temperature, pressure and chemical composition of the atmosphere, atmospheric precipitation, ocean temperature, volcanic eruptions, and so on. Ultimately, these are geodynamic events on which living beings have little or no influence and therefore must undergo them and adapt to them in order to survive. The science that studies the climate and environmental conditions of the earth in the millions of years since its origin is called Paleoclimatology.

Other Environmental and Climatic Factors on the Geosphere Include: Solar activity, the composition of the atmosphere, the layout of the continents, ocean currents, the gravitational effect of the Moon, the Earth’s orbit, etc. and they are such that they can modify the energy distribution and balance of the earth, and consequently alter the earth’s climate.

Planetary Cycles

Even more important are the astral factors that contribute to modifying the climatic situation of the earth, they play a decisive role, they include: the earth’s orbit and the quantity of solar rays that reach its hemispheres, the alternation of the equinoxes , the orbital eccentricity and the inclination of the Earth’s axis. They are all temporal events that have a cyclical trend [14]. These cycles explain the global climate changes that occurred over millions of years corresponding to the periods of glaciation/ deglaciation described by Paleoclimatology. While the fundamental factors that determine the alternation of the seasons and the day-night cycle are:

• The elliptical orbit that describes the earth and
• The rotation period different from the revolution period of our planet.

The elliptical orbit of the Earth is the resultant between its escape kinetic energy and the solar attraction force; (Kepler’s law: «the planets orbit in elliptical orbits, of which the star occupies one of the foci.») (Figure 4). Therefore the fundamental causes that fuel the cyclical nature of events on earth are dependent on the orbital movements of the earth with respect to the sun. The sun emits electromagnetic energy in the form of light, heat and gravitational force which are constant. The earth, with its movements of rotation on its orbit and revolution on its axis, determines the geodynamic rhythms that modify its energy content. Along its orbit the earth undergoes the electromagnetic and gravitational forces of the sun, when it is closest to the sun (perihelion) the forces are maximum, as it travels along its elliptical orbit the forces become smaller and smaller until they reach a minimum when the distance from the sun is maximum (aphelion). The rotational motion on the Earth’s axis has a period of 24 hours and determines the circadian cycle. Worth noting is that the total energy that the earth absorbs from the sun is constant, what varies is the exposure of its surface to solar rays, which follow a circadian rhythm. Since the earth’s rotation axis is inclined by approximately 23° with respect to its orbital plane, there is a different exposure of the earth’s surfaces to the sun and this determines seasonal climate changes. Milutin ‘s theory Milanković (1879-1958) the global effects of the cyclic variations of the Earth’s orbital parameters have a preponderant effect on its climate [15]. The Earth’s orbital rotation and revolution time follow a wave rhythm, but on a different time scale.

Figure 4

Evolution of the Circadian Rhythm

The mechanism of the circadian rhythm is the result of millenary evolution which has favored the link between astral and environmental conditions of the terrestrial biosphere and the availability of natural resources. The consequent need for organisms to follow cosmic cycles and synchronize with them has guaranteed the best conditions for their survival [16]. Such conditions require the best sun exposure and optimal temperature necessary for vital activities. These are the conditions observed during the day and in the mild spring season in which all nature produces the luxuriant quantity of food and heat, and the life cycles of plants and animals synchronically reach the maximum level of bioenergetic and nutritional content. Even nocturnal animals, which do not enjoy the benefits of sunlight, still use the best environmental conditions to which they are adapted to obtain food.

From what we have described so far, it can be concluded that the elementary functional unit of the Circadian rhythm of living beings is constituted, in short, by the ability of their biofeedback system to respond with adaptation to the conditions imposed by the cosmic environment. If we examine all the ways in which the Circadian rhythm occurs in living beings, we see that each of these is equipped with receptors suitable for the stimulus that must recognize (Figures 1 & 2). A particular sequence of reactions synchronizes the biological events of living beings to the rhythm of the environmental stimuli received, and transforms them into their physiological behaviors: sleep/wake, hormonal secretion, the reproductive cycle, chlorophyll photosynthesis, and so on [17]. The fundamental mechanism that makes the circadian rhythm work is formed by the Peacemaker systems that keep active the molecular complexes that must respond to cyclic environmental stimuli. These pacemaker mechanisms are defined as “biological oscillators” in analogy to the oscillatory systems of electromechanical mechanisms.

Circadian oscillators are formed by special cell groups present in almost all living organisms, from bacteria to humans, they present rhythmic periods of constant activity of approximately 24 hours (circa diano) even in the absence of external temporal signals. Circadian oscillators synchronize the rhythmic physiological and behavioral changes of living organisms to 24-hour oscillations of the external environment. The molecular nature of circadian oscillators, termed the internal molecular clock , varies from species to species [18-20]. The molecular mechanism of their functioning is extremely complex and is not the subject of this article. In extreme summary, we can say that the mechanism of the internal biological clock is regulated by the expression of the Period (Per) and Cryptochome ( Cry ) genes which control the ionic flow in the cell membranes, (acting on the gradient of the Na/K ions of the cell membrane acting on the synthesis of ATPase ) and consequently modulate the state of excitation of the cell membrane potential, which is activated or deactivated by external light stimuli [21,22].

They are the genes that turn the internal clock on or off, with their effect on ion flows [23-25]. Recent acquisitions on the mechanism that regulates the concentration of metal ions, Mg²⁺, Na⁺, K⁺, Ca²⁺, during the circadian rhythm, have shown that it is analogous to the genetic mechanism that modulates ionic conductances and is conserved in all the species. This evidence has rekindled the interest of previous observations on the role of these ions as key modulators and triggers of circadian cell function, especially for electrically active cells. This manuscript relates the cellular pacemaker of living things to the synchrony of astral rhythms, which condition their circadian behavior. The basic concept we support is that the pacemaker is fundamental for keeping cellular oscillators active and is responsible for the circadian rhythm of all living things, which can thus modulate their metabolic activity independently of environmental events. In this way they can anticipate the synchronism of their internal clock to the inconstant rhythmicity of environmental conditions [26,27].

It is a biphasic mechanism in which the system keeps the underlying cellular excitability active which can thus follow circadian variations and maintain metabolic homeostasis with periods of activity and periods of rest.

Paraphrasing we could say that the circadian rhythm is the orchestra master who conducts the

Symphony That Performs the Molecular Oscillator: The cellular oscillator is the set of instruments that perform the music, while the circadian rhythm is the orchestra leader who gives the performance times.

Circadian oscillators are endogenous systems of autonomous cell groups that maintain their rhythm even in the absence of external temporal signals. Importantly, the inclusion of oscillatory cell groups in the endogenous clock was achieved throughout evolution in response to repeated specific signals, such as light/dark alternation. It is now well established that the peripheral tissues of mammals also contain independent oscillators, but are functionally synchronized by the central clock present in the Central Nervous System. The circadian clock consists of three operational components: the intrinsic pacemaker, the stimulus input and the metabolic responses [28-33], (Figure 5).

Figure 5

Circadian Rhythm and Physiological Activities

Many automatic physiological processes of individual organisms exhibit daily and/or circadian rhythmicity, including body temperature control, cardiovascular function, melatonin secretion, cortisol secretion, metabolism and sleep [34-36], (Figure 6A). Although the circadian period can be temporarily influenced by environmental factors, the basic period value is genetically determined. Different species have different circadian values, and single-gene mutations that affect the circadian cycle have been described in various species. The primary mammalian circadian pacemaker is located in the suprachiasmatic nucleus in the ventral rostrum of the hypothalamus (Figure 6B). It was identified in 1972 and functional studies have repeatedly confirmed the result achieved since then.

Figure 6

Circadian Rhythm in Therapy

Numerous clinical works have demonstrated that the circadian rhythm, in addition to influencing the main physiological activities described in the previous paragraph, also exerts a direct action on the responses of the basic values of the fundamental clinical parameters. One piece of data for all is represented by the variations observed in blood cell counts at different moments of the circadian rhythm [37- 40]. Equally evident is the impact it has on various pathological manifestations and their degree of severity. From this body of evidence was derived the concept that relates the temporal effectiveness of medicines in relation to the circadian rhythm, and gave rise to Chronopharmacology. The new discipline evaluates patients’ responses to the administration of drugs, their behavior, blood distribution, their therapeutic effect, as the circadian rhythm varies. This resulted in the analogy between the parameters described by Pharmacology, translated into chronopharmacological parameters, thus distinguishing Chronokinetics and chronodynamics referring to the interdependence between the dose of the drug, its distribution, its metabolism and the time of its administration. The investigation conducted following this new approach provided encouraging results which recommend the adoption of this new Chronotherapeutic method.

Circadian Rhythm and Evolution

In order to introduce this topic, a premise is necessary to clarify the difference between two concepts: biological clock and circadian rhythm. The biological clock or “biological oscillator” is the physiological mechanism within biological organisms by which they respond and adapt to the circadian rhythm. The circadian rhythm consists of the cyclical temporal repetition of sidereal events to which organisms must adapt. Therefore the sidereal chronological rhythm exerts its direct action on biological events, and assumes it when living beings depend diachronically and synergistically on its evolution. In works on this topic these two concepts are confused and the automatic mechanism internal to living organisms is improperly defined as circadian rhythm. Having made this premise, let’s see how sidereal evolution modifies biological evolution. The first event that triggered the mechanism of interdependence of living beings and astral bodies on earth occurred in Archea, single-celled prokaryotic organisms, and was described in Cyanobacteria and other primitive organisms. Starting from these primitive organisms, it was perfected during the evolution of individual living species according to their specific habitats [41,42] (Figure 7).

Figure 7

The mechanism we hypothesize in this article schematically involves two phases:

• Adaptation of biological oscillators to cosmic rhythms;
• Adaptation and incorporation of biological oscillators in individual living beings and their evolution based on specific environmental needs.

This hypothesis assigns a fundamental role to biological oscillators in the evolutionary process, because they have been decisive in the formation of circadian rhythms and their adaptive mechanism to external changes.

We do not describe the very complicated molecular and evolutionary mechanisms that have produced the circadian rhythms present in different living species, also because they are not completely clarified. We only give a summary description of the events in their complexity to explain the key steps, summarized in (Figure 7). The first event was the formation of the constituent proteins of the plastids which were then incorporated into the ancestral forms of the Cyanobacteria, and of the proteins that will give life to the mitochondria in the Proteobacteria.

Thus Cyanobacteria acquired the ability to use sunlight and oxygen for chlorophyll synthesis, while Proteobacteria introduced the mechanism of nutrient oxidation. Cyanobacteria, being the first to use chloroplasts for photosynthesis, had to adapt to the cyclical variations in sunlight, starting the evolution of circadian rhythms, The endosymbiosis of Cyanobacteria and Proteobacteria in eukaryotic cells is the next step during evolution. Endosymbiotic bacteria will transform into the organelles, chloroplasts and mitochondria one of the most crucial events in the cellular evolution of eukaryotic organisms [43].

In the context of the complex dynamics that regulate living matter in all its expressions, Chronobilogy offers a valid tool for investigation and knowledge to understand the origin and evolution of life on earth. Compared to other disciplines that work in this field, such as biology, biochemistry, physiology, quantum biology, and so on, chronobiology offers the advantage of harmonizing biological events with the astral phenomena circumscribed to our system in a holistic conception. solar. By doing so, it presents a plausible explanation of the current and objective events that may have conditioned, if not generated, life on earth and the mechanisms of its evolution.

The conception of the evolution of the biosphere as a synchronic event with the cycles of our solar system offers a broader vision than Darwinian theories whose value remains limited to the evolution of the Biosphere bound by the environment according to the random mutation scheme - selection and adaptation to its own Habitat. We leave to quantum physics the task of answering the difficult question on the origin of matter and the universe with the rigor of its esoteric mathematical formulas and the scientific certainty of its doctrine. We ordinary mortals are gratified and fascinated by the idea of being children of the same mysterious and corporeal matter of which the stars are made, and of not being the children of some unknown entity. And that in itself is very comforting.

Authors declare that they have no conflicts of interest in this article.

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