Far infrared ray irradiation attenuates apoptosis and cell death of cultured keratinocytes stressed by dehydration

Far-infrared radiation and its therapeutic parameters: A superior alternative for future regenerative medicine?

In future regenerative medicine, far-infrared radiation (FIR) may be an essential component of optical therapy. Many studies have confirmed or validated the efficacy and safety of FIR in various diseases, benefiting from new insights into FIR mechanisms and the excellent performance of many applications. However, the lack of consensus on the biological effects and therapeutic parameters of FIR limits its practical applications in the clinic. In this review, the definition, characteristics, and underlying principles of the FIR are systematically illustrated. We outline the therapeutic parameters of FIR, including the wavelength range, power density, irradiation time, and distance. In addition, the biological effects, potential molecular mechanisms, and preclinical and clinical applications of FIR are discussed. Furthermore, the future development and applications of FIR are described in this review. By applying optimal therapeutic parameters, FIR can influence various cells, animal models, and patients, eliciting diverse underlying mechanisms and offering therapeutic potential for many diseases. FIR could represent a superior alternative with broad prospects for application in future regenerative medicine.

Far infrared irradiation suppresses experimental arthritis in rats by down-regulation of genes involved inflammatory response and autoimmunity

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FIR treatment improved adjuvant arthritis in rats.

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FIR exposure inhibited the inflammatory genes expression of synovial tissues in AIA rats.

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FIR exposure down-regulated inflammatory genes expression mainly through transcription factors AP-1, CEBPα, CEBPβ, c-Fos, GR, HNF-3β, USF-1, and USF-2.

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FIR irradiation may exhibit anti-arthritic effects through inactivation of the MAPK, PI3K-Akt, and NF-κB signaling pathways.

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Far Infrared Radiation Therapy for Gynecological Cancer-Related Lymphedema Is an Effective and Oncologically Safe Treatment: A Randomized-Controlled Trial

Background: Gynecological cancer-related lymphedema (GCRL) is a devastating condition that adversely influences function, health, and quality of life. We conducted a randomized-controlled clinical study as well as in vitro experiments to investigate the efficacy and safety of far infrared radiation (FIR) to treat lymphedema in patients having previously undergone surgery for gynecological tumors. Materials and Methods: Seventy-four women with GCRL, cancer free for 5 years or more, were randomly allocated into two treatment groups: standard of care with bandage treatment and treatment with FIR plus bandage. Variations of fluid, circumference of lymphedematous limbs, serum tumor markers (cancer antigen 125 [CA125]), inguinal-pelvic lymph nodes, vagina, lungs, and adverse reactions were assessed after 1 year. In vitro experiments examined the effects on cell viability, proliferation, apoptosis, and the cell cycle of fibroblast, A2780, SKOV-3, HELA, and Ishikawa cells. Results: The FIR+bandage group showed significantly decreased tissue fluid and reduced limb circumference (p < 0.05) in comparison with the control group at 1 year. There was no increase of serum CA125 in both groups, and no recurrence of neoplasia or lymphadenopathy was detected. No adverse reactions were recorded. In addition, no changes were detected after FIR treatment for fibroblast, A2780, SKOV-3, HELA, and Ishikawa cells in cell viability, proliferation, apoptosis, and cell cycle. Conclusion: FIR can be used to treat patients with GCRL following gynecological cancer treatment. Following clinical and experimental studies, we confirm that FIR is an oncologically safe treatment for lymphedema in gynecological tumor patients.

Far infrared radiation promotes rabbit renal proximal tubule cell proliferation and functional characteristics, and protects against cisplatin-induced nephrotoxicity

Far infrared radiation, a subdivision of the electromagnetic spectrum, is beneficial for long-term tissue healing, anti-inflammatory effects, growth promotion, sleep modulation, acceleration of microcirculation, and pain relief. We investigated if far infrared radiation is beneficial for renal proximal tubule cell cultivation and renal tissue engineering. We observed the effects of far infrared radiation on renal proximal tubules cells, including its effects on cell proliferation, gene and protein expression, and viability. We also examined the protective effects of far infrared radiation against cisplatin, a nephrotoxic agent, using the human proximal tubule cell line HK-2. We found that daily exposure to far infrared radiation for 30 min significantly increased rabbit renal proximal tubule cell proliferation in vitro, as assessed by MTT assay. Far infrared radiation was not only beneficial to renal proximal tubule cell proliferation, it also increased the expression of ATPase Na+/K+ subunit alpha 1 and glucose transporter 1, as determined by western blotting. Using quantitative polymerase chain reaction, we found that far infrared radiation enhanced CDK5R1, GNAS, NPPB, and TEK expression. In the proximal tubule cell line HK-2, far infrared radiation protected against cisplatin-mediated nephrotoxicity by reducing apoptosis. Renal proximal tubule cell cultivation with far infrared radiation exposure resulted in better cell proliferation, significantly higher ATPase Na+/K+ subunit alpha 1 and glucose transporter 1 expression, and significantly enhanced expression of CDK5R1, GNAS, NPPB, and TEK. These results suggest that far infrared radiation improves cell proliferation and differentiation. In HK-2 cells, far infrared radiation mediated protective effects against cisplatin-induced nephrotoxicity by reducing apoptosis, as indicated by flow cytometry and caspase-3 assay.

Far-infrared suppresses skin photoaging in ultraviolet B-exposed fibroblasts and hairless mice

Ultraviolet (UV) induces skin photoaging, which is characterized by thickening, wrinkling, pigmentation, and dryness. Collagen, which is one of the main building blocks of human skin, is regulated by collagen synthesis and collagen breakdown. Autophagy was found to block the epidermal hyperproliferative response to UVB and may play a crucial role in preventing skin photoaging. In the present study, we investigated whether far-infrared (FIR) therapy can inhibit skin photoaging via UVB irradiation in NIH 3T3 mouse embryonic fibroblasts and SKH-1 hairless mice. We found that FIR treatment significantly increased procollagen type I through the induction of the TGF-β/Smad axis. Furthermore, UVB significantly enhanced the expression of matrix metalloproteinase-1 (MMP-1) and MMP-9. FIR inhibited UVB-induced MMP-1 and MMP-9. Treatment with FIR reversed UVB-decreased type I collagen. In addition, FIR induced autophagy by inhibiting the Akt/mTOR signaling pathway. In UVB-induced skin photoaging in a hairless mouse model, FIR treatment resulted in decreased skin thickness in UVB irradiated mice and inhibited the degradation of collagen fibers. Moreover, FIR can increase procollagen type I via the inhibition of MMP-9 and induction of TGF-β in skin tissues. Therefore, our study provides evidence for the beneficial effects of FIR exposure in a model of skin photoaging.