Modulation of extracellular ATP content of mast cells and DRG neurons by irradiation: studies on underlying mechanism of low-level-laser therapy

Hybrid Therapeutic Device (CUHK-OA-M2) for Relieving Symptoms Induced by Knee Osteoarthritis

The symptoms of knee osteoarthritis (KOA) severely affect the life quality of the elderly population. Low-level laser therapy, heat therapy, and massage therapy are widely used as independent treatments for joint disorders. However, there are very limited reports of a combination of these therapies into an integrated device for KOA so far. This study aims to develop a novel hybrid therapeutic device that can meet various requirements for knee therapy. Our hybrid therapeutic device (CUHK-OA-M2) integrated with low-level laser therapy, heat therapy, and local massage therapy can effectively provide patients with KOA with relief from their clinical symptoms. A pilot test of 50 community-dwelling elderly volunteers with KOA was performed. Finally, 43 volunteers completed two treatment periods (30 days each) and two post-treatment periods (30 days each). The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were collected and analyzed after each period. The outputs of the low-level laser, heating, and massage therapies significantly decreased the WOMAC scores in terms of pain, stiffness, function and total WOMAC after two treatment periods (p < 0.05). Although the score increased slightly after the post-treatment period, it was still lower than the baseline, indicating the treatment outcome could last for an extended period. Therefore, our CUHK-OA-M2 device, as an integrated multi-functional hybrid therapeutic device, is therapeutically significant for treating osteoarthritis symptoms on the knee joints of elderly subjects.

Changes in Cell Biology under the Influence of Low-Level Laser Therapy

Low-level laser therapy (LLLT) has become an important part of the therapeutic process in various diseases. However, despite the broad use of LLLT in everyday clinical practice, the full impact of LLLT on cell life processes has not been fully understood. This paper presents the current state of knowledge concerning the mechanisms of action of LLLT on cells. A better understanding of the molecular processes occurring within the cell after laser irradiation may result in introducing numerous novel clinical applications of LLLT and potentially increases the safety profile of this therapy.

Acupuncture modulates extracellular ATP levels in peripheral sensory nervous system during analgesia of ankle arthritis in rats

As an ancient analgesia therapy, acupuncture has been practiced worldwide nowadays. A good understanding of its mechanisms will offer a promise for its rational and wider application. As the first station of pain sensation, peripheral sensory ganglia express pain-related P2X receptors that are involved in the acupuncture analgesia mechanisms transduction pathway. While the role of their endogenous ligand, extracellular ATP (eATP), remains less studied. This work attempted to clarify whether acupuncture modulated eATP levels in the peripheral sensory nerve system during its analgesia process. Male Sprague-Dawley rats underwent acute inflammatory pain by injecting Complete Freund's Adjuvant in the unilateral ankle joint for 2 days. A twenty-minute acupuncture was applied to ipsilateral Zusanli acupoint. Thermal hyperalgesia and tactile allodynia were assessed on bilateral hind paws to evaluate the analgesic effect. eATP of bilateral isolated lumbar 4-5 dorsal root ganglia (DRGs) and sciatic nerves were determined by luminescence assay. Nucleotidases NTPDase-2 and -3 in bilateral ganglia and sciatic nerves were measured by real-time PCR to explore eATP hydrolysis process. Our results revealed that acute inflammation induced bilateral thermal hyperalgesia and ipsilateral tactile allodynia, which were accompanied by increased eATP levels and higher mechano-sensitivity of bilateral DRGs and decreased eATP levels of bilateral sciatic nerves. Acupuncture exerted anti-nociception on bilateral hind paws, reversed the increased eATP and mechanosensitivity of bilateral DRGs, and restored the decreased eATP of bilateral sciatic nerves. NTPDase-2 and -3 in bilateral ganglia and sciatic nerves were inconsistently modulated during this period. These observations indicate that eATP metabolism of peripheral sensory nerve system was simultaneously regulated during acupuncture analgesia, which might open a new frontier for acupuncture research.

Electroacupuncture alleviates diabetic neuropathic pain in rats by suppressing P2X3 receptor expression in dorsal root ganglia

Diabetic neuropathic pain (DNP) is a troublesome diabetes complication all over the world. P2X3 receptor (P2X3R), a purinergic receptor from dorsal root ganglion (DRG), has important roles in neuropathic pain pathology and nociceptive sensations. Here, we investigated the involvement of DRG P2X3R and the effect of 2 Hz electroacupuncture (EA) on DNP. We monitored the rats' body weight, fasting blood glucose level, paw withdrawal thresholds, and paw withdrawal latency, and evaluated P2X3R expression in DRG. We found that P2X3R expression is upregulated on DNP, while 2 Hz EA is analgesic against DNP and suppresses P2X3R expression in DRG. To evaluate P2X3R involvement in pain modulation, we then treated the animals with A317491, a P2X3R specific antagonist, or α β-me ATP, a P2X3R agonist. We found that A317491 alleviates hyperalgesia, while α β-me ATP blocks EA's analgesic effects. Our findings indicated that 2 Hz EA alleviates DNP, possibly by suppressing P2X3R upregulation in DRG.

Quantum biology in low level light therapy: death of a dogma

Background

It is shown that despite exponential increase in the number of clinically exciting results in low level light therapy (LLLT), scientific progress in the field is retarded by a wrong fundamental model employed to explain the photon-cell interaction as well as by an inadequate terminology. This is reflected by a methodological stagnation in LLLT, persisting since 1985. The choice of the topics is, by necessity, somewhat arbitrary. Obviously, we are writing more about the fields we know more about. In some cases, there are obvious objective reasons for the choice. Progress in LLLT is currently realized by a trial and error process, as opposed to a systematic approach based on a valid photon-cell interaction model.

Methods

The strategy to overcome the current problem consists in a comprehensive analysis of the theoretical foundation of LLLT, and if necessary, by introducing new interaction models and checking their validity on the basis of the two pillars of scientific advance (I) agreement with experiment and (II) predictive capability. The list of references used in this work, does contain a representative part of what has been done in the photon-cell interaction theory in recent years, considered as ascertained by the scientific community.

Results

Despite the immense literature on the involvement of cytochrome c oxidase (COX) in LLLT, the assumption that COX is the main mitochondrial photoacceptor for R-NIR photons no longer can be counted as part of the theoretical framework proper, at least not after we have addressed the misleading points in the literature. Here, we report the discovery of a coupled system in mitochondria whose working principle corresponds to that of field-effect transistor (FET). The functional interplay of cytochrome c (emitter) and COX (drain) with a nanoscopic interfacial water layer (gate) between the two enzymes forms a biological FET in which the gate is controlled by R-NIR photons. By reducing the viscosity of the nanoscopic interfacial water layers within and around the mitochondrial rotary motor in oxidatively stressed cells R-NIR light promotes the synthesis of extra adenosine triphosphate (ATP).

Conclusions

Based on the results of our own work and a review of the published literature, we present the effect of R-NIR photons on nanoscopic interfacial water layers in mitochondria and cells as a novel understanding of the biomedical effects R-NIR light. The novel paradigm is in radical contrast to the theory that COX is the main absorber for R-NIR photons and responsible for the increase in ATP synthesis, a dogma propagated for more than 20 years.

Besides Photothermal Effects, Low-Level CO2 Laser Irradiation Can Potentiate Skin Microcirculation Through Photobiomodulation Mechanisms

Background: Improvement of microcirculation is one of the important mechanisms of low-level laser therapy (LLLT) to treat some diseases such as wound healing. Most previous studies have been carried out with multiple lasers other than the 10,600-nm CO₂ laser. Recently, the CO₂ laser has been used not only as a tool for excision of soft tissues but also for therapeutic applications. Objective: To study whether low-level CO₂ laser irradiation can influence microcirculation and further explore the underlying mechanisms. Methods: Seventy-milliwatt (70-mW) CO₂ lasers irradiated the forearms of 12 participants and skin blood perfusion (SkBP) was measured with a laser speckle imager. The thermal effect of irradiation was evaluated by measuring the irradiated skin in vivo and the exposed cell suspensions in vitro. Extracellular adenosine triphosphate (eATP) of the human mast cell line (HMC-1) is assessed by luciferin-luciferase assay to explore the potential mechanisms. Results: Irradiation caused dose-dependent increase in SkBP. At a medium dose of 262 J/cm², SkBP reached its maximum value at 195.8% ± 18.6% of the baseline (n = 12, p < 0.01). Such laser irradiation had a mild thermal effect, heating local skin temperature (SkT) by 6.1°C ± 0.3°C (n = 10) and warming cell suspensions by 4.5°C ± 0.8°C (n = 6). Irradiation dose-dependently lowered eATP levels of HMC-1 cells in vitro. At a medium dose of 262 J/cm², eATP levels declined to the minimum at 74.8% ± 5.5% of the baseline (n = 12, p < 0.01). This downregulation effect could be significantly inhibited by 100-μM ARL67156, a nonspecific ecto-ATPase inhibitor. On the contrary, heating itself slightly raised the level of eATP. Conclusions: Low-level CO₂ laser irradiation can improve microcirculation. Besides the thermal effect, regulation of extravascular eATP by the photobiomodulation mechanism may be involved. This implies that CO₂ lasers might be used in LLLT.

Acupuncture for the Treatment of Animal Pain

Acupuncture is recognized to induce multifactorial changes in the neuroregulatory aspects of pain physiology. Many aspects overlap with known receptor interactions of commonly used analgesic drugs, and acupuncture can increase the efficacy or replace the use of these pharmacologic pain treatments. This article discusses the currently recognized components of the pain pathways that are modified by acupuncture. It introduces the role of fibroblasts and fascia in mechanotransduction and discusses the ways in which this provides a link between the acupuncture needle and the nervous system and is a conduit for extracellular fluid movement, lymphatics, and the immune system.

Pulsed Near Infrared Transcranial and Intranasal Photobiomodulation Significantly Modulates Neural Oscillations: a pilot exploratory study

Transcranial photobiomodulation (tPBM) is the application of low levels of red or near-infrared (NIR) light to stimulate neural tissues. Here, we administer tPBM in the form of NIR light (810 nm wavelength) pulsed at 40 Hz to the default mode network (DMN), and examine its effects on human neural oscillations, in a randomized, sham-controlled, double-blinded trial. Using electroencephalography (EEG), we found that a single session of tPBM significantly increases the power of the higher oscillatory frequencies of alpha, beta and gamma and reduces the power of the slower frequencies of delta and theta in subjects in resting state. Furthermore, the analysis of network properties using inter-regional synchrony via weighted phase lag index (wPLI) and graph theory measures, indicate the effect of tPBM on the integration and segregation of brain networks. These changes were significantly different when compared to sham stimulation. Our preliminary findings demonstrate for the first time that tPBM can be used to non-invasively modulate neural oscillations, and encourage further confirmatory clinical investigations.

Improvement in infected wound healing in type 1 diabetic rat by the synergistic effect of photobiomodulation therapy and conditioned medium

We investigated the effects of photobiomodulation therapy (PBMT) and conditioned medium (CM) of human bone marrow mesenchymal stem cells (hBM-MSC) individually and/or in combination on the stereological parameters and the expression of basic fibroblast growth factor (bFGF), hypoxia-inducible factor (HIF-1α), and stromal cell-derived factor-1α (SDF-1α) in a wound model infected with methicillin-resistant Staphylococcus aureus (MRSA) in diabetic rats. CM was provided by culturing hBM-MSCs. Type 1 diabetes mellitus (T1DM) was induced in 72 rats, divided into four groups, harboring 18 rats each: group 1 served as a control group, group 2 received PBMT, group 3 received CM, and group 4 received CM + PBMT. On days 4, 7, and 15, six animals from each group were euthanized and the skin samples were separated for stereology examination and gene expression analysis by real-time polymerase chain reaction. In the CM + PBMT, CM, and PBMT groups, significant decreases were induced in the number of neutrophils (1460 ± 93, 1854 ± 138, 1719 ± 248) and macrophages (539 ± 69, 804 ± 63, 912 ± 41), and significant increases in the number of fibroblasts (1073 ± 116, 836 ± 75, 912 ± 41) and angiogenesis (15 230 ± 516, 13 318 ± 1116, 14 041 ± 867), compared with those of the control group (2690 ± 371, 1139 ± 145, 566 ± 90, 12 585 ± 1219). Interestingly, the findings of the stereological examination in the CM + PBMT group were statistically more significant than those in the other groups. In the PBMT group, in most cases, the expression of bFGF, HIF-1α, and SDF-1α, on day 4 (27.7 ± 0.14, 28.8 ± 0.52, 27.5 ± 0.54) and day 7 (26.8 ± 1.4, 29.6 ± 1.4, 28.3 ± 1.2) were more significant than those in the control (day 4, 19.3 ± 0.42, 25.5 ± 0.08, 22.6 ± 0.04; day 7, 22.3 ± 0.22, 28.3 ± 0.59, 24.3 ± 0.19) and other treatment groups. The application of PBMT + CM induced anti-inflammatory and angiogenic activities, and hastened wound healing process in a T1 DM model of MRSA infected wound.

Purines Change at Acupoints along the Pericardium Meridian in Healthy and Myocardial Ischemic Rats

OBJECTIVE

To quantify the purine concentrations of the acupoints along the pericardium and nonpericardium meridians under healthy and myocardial ischemia conditions to investigate the relationship between acupoint purine change and body functional status in rats.

METHODS

A total of 70 rats underwent an operation for myocardial ischemia, while 40 of them survived. They were randomly assigned to the following 5 subgroups: Neiguan (PC 6), Quze (PC 3), Tianquan (PC 2), Quchi (LI 11), and Jianyu (LI 15). Simultaneously, another 40 healthy rats were also randomized into the same 5 subgroups as the control group. The tissue fluids at the acupoints were collected by microdialysis for 30 min. Subsequently, the concentration of adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP), and adenosine (ADO) were quantified using the high-performance liquid chromatography method.

RESULTS

Compared with the healthy group, the ADO at PC 6 (P=0.012), PC 3 (P=0.038), PC 2 (P=0.024), and LI 15 (P=0.042) obviously increased in the model group, while no significant difference was observed at LI 11 (P=0.201). However, ATP, ADP, and AMP manifested no significant changes in these areas, except for ATP at LI 15 (P=0.036).

CONCLUSIONS

Myocardial ischemia could induce an increase in ADO at acupoints of the upper arm and shoulder area, suggesting that the body functional status could affect the responsiveness of acupoints. The status of these acupoints could be pathogenically activated by disease, and distribution following some specific courses.

Mast cell deficiency attenuates acupuncture analgesia for mechanical pain using c-kit gene mutant rats

Background

Acupuncture therapy plays a pivotal role in pain relief, and increasing evidence demonstrates that mast cells (MCs) may mediate acupuncture analgesia. The present study aims to investigate the role of MCs in acupuncture analgesia using c-kit gene mutant-induced MC-deficient rats.

Materials and methods

WsRC-Ws/Ws rats and their wild-type (WT) littermates (WsRC-+/+) were used. The number of MCs in skin of ST36 area was compared in two rats after immunofluorescence labeling. Mechanical withdrawal latency (MWL), mechanical withdrawal threshold (MWT), and thermal withdrawal latency (TWL) were measured on bilateral plantar for pain threshold evaluation before and after each stimulus. Acupuncture- and moxibustion-like stimuli (43°C, 46°C heat, 1 mA electroacupuncture [EA], 3 mA EA, and manual acupuncture [MA]) were applied randomly on different days.

Results

Fewer MCs were observed in the skin of ST36 in mutant rats compared to WT rats (P<0.001). For pain thresholds, MWL and MWT were higher in WsRC-Ws/Ws compared to WsRC-+/+ on bilateral paws (P<0.05), but TWL was not different between the two rats (P>0.05). Bilateral MWL and MWT in WsRC-+/+ rats increased significantly after each stimulus compared to baseline (P<0.01, P<0.001). In WsRC-Ws/Ws rats, only noxious stimuli could produce anti-nociceptive effects for mechanical pain (46°C, 3 mA EA, MA) (P<0.01, P<0.001). Additionally, the net increases in MWL and MWT induced by most stimuli were greater in WT than in mutant rats (P<0.05). For thermal nociception, either high- or low-intensity stimuli could significantly augment TWL in two rats (P<0.001), and the net increases of TWL evoked by most stimuli were to the same extent in two genetic variants.

Conclusion

MCs influence the basic mechanical but not thermal pain threshold. MCs participate in acupuncture analgesia in mechanical but not in thermal nociception, in that MC deficiency may attenuate the mechanical analgesia evoked by high-intensity stimuli and eliminate analgesia provoked by low-intensity stimuli.

A Retrospective Study of Non-thermal Laser Therapy for the Treatment of Toenail Onychomycosis

Objective: The objective of this study was to assess the efficacy of non-thermal laser therapy for treating toenail onychomycosis. Design: This retrospective study analyzed the results of three nonrandomized, open-label studies. The device used was a 635nm/405nm dual-diode laser. Affected toenails were treated for 12 minutes weekly for 2 or 4 weeks. Setting: Treatments occurred in clinic and private office settings. Participants: Subjects with onychomycosis-infected toenails were enrolled. Measurements: Fifty great toenails were included in the analysis based on visually identifiable onychomycosis; thickened, discolored nail plate; and confirmed etiology of onychomycosis. Changes in the extent of clear nail bed was measured using multi-platform image manipulation software. The primary outcome measure was the percent of toenails attaining ≥3mm of clear nail growth during the six-month post-treatment period. Overall study success was defined as ≥60 percent of treated toenails meeting the individual success criteria. The secondary outcome measure was change in the length of clear nail bed. Results: Most treated toenails (67%) achieved individual treatment success. The extent of clear nail at baseline increased by a mean of 5.18 (4.76) mm after 6 months (p<0.0001). In addition, 89 percent of treated toenails demonstrated an increase in clear nail across the six-month study period. No adverse events were reported. Conclusion: Non-thermal laser therapy is safe and effective for increasing the extent of clear nail in onychomycosis-infected toenails following one weekly treatment for four weeks. ClinicalTrials.gov Identifier: NCT02588599.

Photobiomodulation with non-thermal lasers: Mechanisms of action and therapeutic uses in dermatology and aesthetic medicine

BACKGROUND

Non-thermal laser therapy in dermatology, is a growing field in medical technology by which therapeutic effects are achieved by exposing tissues to specific wavelengths of light.

OBJECTIVES

The purpose of this review was to gain a better understanding of the science behind non-thermal laser and the evidence supporting its use in dermatology.

METHODS

A group of dermatologists and surgeons recently convened to review the evidence supporting the use of non-thermal laser for body sculpting, improving the appearance of cellulite, and treating onychomycosis.

RESULTS

The use of non-thermal laser for body sculpting is supported by three randomized, double-blind, sham-controlled studies (N = 161), one prospective open-label study (N = 54), and two retrospective studies (N = 775). Non-thermal laser application for improving the appearance of cellulite is supported by one randomized, double-blind, sham-controlled study (N = 38). The use of non-thermal laser for the treatment of onychomycosis is supported by an analysis of three non-randomized, open-label studies demonstrating clinical improvement of nails (N = 292).

CONCLUSIONS

Non-thermal laser is steadily moving into mainstream medical practice, such as dermatology. Although present studies have demonstrated the safety and efficacy of non-thermal laser for body sculpting, cellulite reduction and onychomycosis treatment, studies demonstrating the efficacy of non-thermal laser as a stand-alone procedure are still inadequate.

Acupuncture-Induced Analgesia: A Neurobiological Basis in Purinergic Signaling

Chronic pain is a debilitating and rather common health problem. The present shortage in analgesic drugs with a favorable spectrum but without remarkable side effects furthered the search for alternative therapeutic manipulations. Increasing evidence from both basic and clinical research on acupuncture, a main alternative therapy of traditional Chinese medicine, suggests that chronic pain is sensitive to acupuncture procedures. Clarification of the underlying mechanisms is a challenge of great theoretical and practical significance. The seminal hypothesis of Geoffrey Burnstock and the astounding findings of Maiken Nedergaard on the involvement of purinergic signaling in the beneficial effects of acupuncture fertilized the field and led to an intensification of research on acupurines. In this review, we will summarize the state-of-the-art situation and try to forecast how the field is likely to develop in the future.