Far-Infrared Therapy Based on Graphene Ameliorates High-Fat Diet-Induced Anxiety-Like Behavior in Obese Mice via Alleviating Intestinal Barrier Damage and Neuroinflammation

The consumption of a high-fat diet (HFD) has been implicated in the etiology of obesity and various neuropsychiatric disturbances, including anxiety and depression. Compelling evidence suggests that far-infrared ray (FIR) possesses beneficial effects on emotional disorders. However, the efficacy of FIR therapy in addressing HFD-induced anxiety and the underlying mechanisms remain to be elucidated. Here, we postulate that FIR emitted from a graphene-based therapeutic device may mitigate HFD-induced anxiety behaviors. The graphene-FIR modify the gut microbiota in HFD-mice, particularly by an enriched abundance of beneficial bacteria Clostridiaceae and Erysipelotrichaceae, coupled with a diminution of harmful bacteria Lachnospiraceae, Anaerovoracaceae, Holdemania and Marvinbryantia. Graphene-FIR also improved intestinal barrier function, as evidenced by the augmented expression of the tight junction protein occludin and G protein-coupled receptor 43 (GPR43). In serum level, we observed the decreased free fatty acids (FFA), lipopolysaccharides (LPS), diamine oxidase (DAO) and D-lactate, and increased the glucagon-like peptide-2 (GLP-2) levels in graphene-FIR mice. Simultaneously, inflammatory cytokines IL-6, IL-1β, and TNF-α manifested a decrease subsequent to graphene-FIR treatment in both peripheral and central system. Notably, graphene-FIR inhibited over expression of astrocytes and microglia. We further noticed that the elevated the BDNF and decreased TLR4 and NF-κB expression in graphene-FIR group. Overall, our study reveals that graphene-FIR rescued HFD-induced anxiety via improving the intestine permeability and the integrity of blood-brain barrier, and reduced inflammatory response by down regulating TLR4/NF-κB inflammatory pathway.

Crossover trial of the effects of a far-infrared heater that heats the feet with ceramic balls on autonomic nervous activity and mood states

INTRODUCTION

The accumulation of fatigue and stress creates problems, including reductions in quality of life and productivity.

OBJECTIVES

To investigate the effects of a far-infrared heater that heats the feet with ceramic balls on autonomic nervous activity and mood states.

METHODS

This study was performed as a crossover trial. Participants comprised 20 women. On different days, each participant underwent 15 min of foot warming with the far-infrared heater (far-infrared group) or remained seated for 15 min (control group). Autonomic nervous activity (low-frequency component/high-frequency component, high-frequency) and mood states scales (Profile of Mood States Second Edition and Two-Dimensional Mood Scale for Self-monitoring and Self-regulation of Momentary Mood States) during the study intervention were measured and compared between groups.

RESULTS

Low-frequency/high-frequency was significantly higher in the control group 10 min after the start of intervention than at baseline (P = .033). Low-frequency/high-frequency was significantly lower in the far-infrared group than in the control group at 5 min (P = .027), 10 min (P = .011), and 15 min (P = .015). High-frequency was significantly higher in the far-infrared group at 5 min (P = .008), 10 min (P = .004), and 15 min (P = .015) than at baseline. High-frequency 5 min after the start of intervention was significantly higher in the far-infrared group than in the control group (P = .033). POMS2 scores improved significantly more in the far-infrared group than in the control group, including in fatigue-inertia (P = .019), tension-anxiety (P = .025), and total mood disturbance (P = .019). Finally, the far-infrared group showed greater improvements in Two-Dimensional Mood Scale-Short Term scores such as stability (P = .002) and pleasure (P = .013).

CONCLUSION

Using the far-infrared heater to heat the feet with ceramic balls stabilized and improved mood, reduced Fatigue-Inertia and Tension-Anxiety, and alleviated total mood disturbance. Parasympathetic nervous system activation was observed from 5 min after the start of heating, suggesting that short-duration heat stimulation of the feet is effective.

Effect of ultrasonic far-infrared synergistic drying on the characteristics and qualities of wolfberry (Lycium barbarum L.)

This study investigated the effects of ultrasonic frequency, ultrasonic power, irradiation height and temperature on the drying characteristics, quality and microstructure of wolfberry by ultrasonic-assisted far-infrared drying. By fitting five commonly used thin-layer drying mathematical models, it was found that the coefficient of determination (R²) of the Weibull model was 0.99400-0.99825, the root mean square error (RMSE) was 1.2162 × 10^-4-4.5209 × 10^-4, and the reduced chi-square (χ²) was 0.00207-0.00663, which was the best fit. Under the application of ultrasound, the average drying rate of wolfberry increased. Compared with natural drying, the polysaccharide content increased by 33.2 % at 250 mm irradiation height, and the total phenol content increased by 44.9 % at 40 kHz ultrasonic frequency. The antioxidant activity was the strongest, and the total flavonoids content was the highest (2.594 mg/g) at 24 W ultrasonic power. By comparing the microstructure of wolfberry under different drying methods, such as a fresh sample, natural drying, hot air drying, and ultrasonic-assisted drying, we found that the ultrasonic assistance increased the number of micropores on the surface of wolfberry, reduced the damage to epidermal cells, reduced the mass transfer resistance of the drying process and accelerated the drying process. This study shows that ultrasonic-assisted far-infrared drying technology played a significant role in the heat and mass transfer of wolfberry drying, and had great potential in the commercial processing of wolfberry.

Integrated Molar Absorptivity of Mid- and Far-Infrared Spectra of Alanine and a Selection of Other Five Amino Acids of Astrobiological Relevance

Alanine and other five proteinogeninc amino acids produced quite easily in exogenous and/or endogenous prebiotic processes, that is, valine, serine, proline, glutamic acid, and aspartic acid (Ala, Val, Ser, Pro, Glu, and Asp, respectively) were studied in the mid- and far-infrared spectral range. This work is an extension of the previous one where other proteinogenic amino acids glycine, isoleucine, phenylalanine, tyrosine, and tryptophan (Gly, Ile, Phe, Tyr, and Trp, respectively) were studied in the mid-infrared and in the far-infrared with the purpose to facilitate the search and identification of these astrobiological and astrochemical relevant molecules in space environments. The molar extinction coefficients (ɛ) of all mid- and far-infrared bands were determined as well as the integrated molar absorptivities (ψ). The mid-infrared spectra of Ala, Val, Ser, Pro, Glu, and Asp were recorded also at three different temperatures from -180°C to nearly ambient temperature and at 200°C. With the reported values of ɛ and ψ, it will be possible to estimate the relative abundance of these molecules in space environments.

Integrated Molar Absorptivity of Mid- and Far-Infrared Spectra of Glycine and Other Selected Amino Acids

A selection of five proteinogenic amino acids-glycine, isoleucine, phenylalanine, tyrosine, and tryptophan-were studied in the mid-infrared and in the far-infrared with the purpose to facilitate the search and identification of these astrobiologically and astrochemically relevant molecules in space environments. The molar extinction coefficients (ɛ) of all mid- and far-infrared bands were determined as well as the integrated molar absorptivities (ψ). The mid-infrared spectra of the five selected amino acids were recorded also at three different temperatures from -180°C to ambient temperature to +200°C. We measured the wavelength shift of the infrared bands caused by temperature; and for the most relevant or temperature-sensitive infrared bands, a series of linear equations were determined relating wavelength position with temperature. Such equations may provide estimates of the temperature of these molecules once detected in astrophysical objects; and with the reported values of ɛ and ψ, it will be possible to estimate the relative abundance of these molecules in space environments.

Transient receptor potential vanilloid 2 mediates the inhibitory effect of far-infrared irradiation on adipogenic differentiation of tonsil-derived mesenchymal stem cells

AIMS

Far-infrared (FIR) irradiation inhibits adipogenic differentiation of tonsil-derived mesenchymal stem cells (TMSCs) by activating Ca²⁺-dependent protein phosphatase 2B (PP2B), but it stimulates osteogenic differentiation in a PP2B-independent pathway. We investigated the potential involvement of transient receptor potential vanilloid (TRPV) channels, a well-known Ca²⁺-permeable channel, in the effects of FIR irradiation on adipogenic or osteogenic differentiation of TMSCs.

METHODS

TMSCs, in the absence or presence of activators or inhibitors, were exposed to FIR irradiation followed by adipogenic or osteogenic differentiation, which was assessed using Oil red O or Alizarin red S staining, respectively. RT-PCR, qRT-PCR, and Western blotting were used to determine gene and protein expression of calcium channels and adipocyte-specific markers.

RESULTS

Treatment with the calcium ionophore ionomycin simulated the inhibitory effect of FIR irradiation on adipogenic differentiation but had no effect on osteogenic differentiation, indicating the involvement of intracellular Ca²⁺ in adipogenic differentiation. Inhibition of pan-TRP channels using ruthenium red reversed the FIR irradiation-induced inhibition of adipogenic differentiation. Among the TRP channels tested, inhibition of the TRPV2 channel by tranilast or siRNA against TRPV2 attenuated the inhibitory effect of FIR irradiation on adipogenic differentiation, accompanied by a decrease in intracellular Ca²⁺ levels. By contrast, activation of the TRPV2 channel by probenecid simulated FIR irradiation-induced inhibition of adipogenic differentiation. Expectedly, the stimulatory effect of FIR irradiation on osteogenic differentiation was independent of the TRPV2 channel.

CONCLUSION

Our data demonstrate that the TRPV2 channel is a sensor/receptor for the inhibited adipogenic differentiation of TMSCs associated with FIR irradiation.

Far-infrared radiation prevents decline in β-cell mass and function in diabetic mice via the mitochondria-mediated Sirtuin1 pathway

Insulin deficiency in type 2 diabetes mellitus (DM) involves a decline in both pancreatic β-cell mass and function. Enhancing β-cell preservation represents an important therapeutic strategy to treat type 2 DM. Far-infrared (FIR) radiation has been found to induce promyelocytic leukemia zinc finger protein (PLZF) activation to protect the vascular endothelium in diabetic mice. The influence of FIR on β-cell preservation is unknown. Our previous study reveals that the biologically effective wavelength of FIR is 8-10 μm. In the present study, we investigated the biological effects of FIR (8-10 μm) on both survival and insulin secretion function of β-cells. FIR reduced pancreatic islets loss and increased insulin secretion in nicotinamide-streptozotocin-induced DM mice, but only promoted insulin secretion in DM PLZF^-/- mice. FIR-upregulated PLZF to induce an anti-apoptotic effect in a β cell line RIN-m5f. FIR also upregulated mitochondrial function and the ratio of NAD⁺/NADH, and then induced Sirtuin1 (Sirt1) expression. The mitochondria Complex I inhibitor rotenone blocked FIR-induced PLZF and Sirt1. The Sirt1 inhibitor EX527 and Sirt1 siRNA inhibited FIR-induced PLZF and insulin respectively. Sirt1 upregulation also increased Ca_V1.2 expression and calcium influx that promotes insulin secretion in β-cells. In summary, FIR-enhanced mitochondrial function prevents β-cell apoptosis and enhances insulin secretion in DM mice through the Sirt1 pathway.

Extending KIDs to the Mid-IR for Future Space and Suborbital Observatories

The galaxy evolution probe (GEP) is a concept for a probe-class space observatory to study the physical processes related to star formation over cosmic time. To do so, the mid- and far-infrared (IR) spectra of galaxies must be studied. These mid- and far-IR observations require large multi-frequency arrays, sensitive detectors. Our goal is to develop low NEP aluminum kinetic inductance detectors (KIDs) for wavelengths of 10-400  μ m for the GEP and a pathfinder long-duration balloon (GEP-B) that will perform precursor GEP science. KIDs for the lower wavelength range (10-100  μ m ) have not been previously implemented. We present an absorber design for KIDs sensitive to wavelengths of 10 μ m shown to have around 75-80% absorption efficiency through ANSYS HFSS (high-frequency structure simulator) simulations, challenges that come with optimizing our design to increase the wavelength range, initial tests on our design of fabricated 10 μ m KIDs, and theoretical NEP calculations.

Drying features of microwave and far-infrared combination drying on white ginseng slices

In this study microwave and far-infrared combination drying were conducted to investigate the effect of microwave and far-infrared heating mode switching point water content (SW), ginseng slice thickness, and far-infrared drying temperature on drying indicators (surface colour difference, ginsenosides content, and surface shrinkage rate) and drying efficiency (drying time) during the process of drying white ginseng slices. Regarding microwave drying, the microwave drying time cannot exceed 150 s, and the ginseng slice water content cannot be less 50%. For the combination drying, SW, far-infrared drying temperature and slice thickness increased, the colour difference and surface shrinkage rate first decreased and then increased, and the content of ginsenosides first increased and then decreased. In addition, the combination drying showed faster drying rate, higher ginsenosides contents value, colour difference (ΔE) value and lower surface shrinkage rate than single far-infrared drying.

Potential mechanisms for the effects of far-infrared on the cardiovascular system - a review

Far-infrared (FIR) is a form of thermal radiation, which may have beneficial effects on cardiovascular health. Clinical studies suggest that FIR irradiation may have therapeutic effects in heart failure, myocardial ischaemia and may improve flow and survival of arteriovenous fistula. Animal studies have suggested a wide range of potential mechanisms involving endothelial nitric oxide synthase and nitric oxide bioavailability, oxidative stress, heat shock proteins and endothelial precursor cells. However, the exact cellular and molecular mechanism of FIR on the cardiovascular system remains elusive. The purpose of this review is to discuss the current literature, focusing on mechanistic studies involving the cardiovascular system, and with a view to highlighting areas for future investigation.

Direct measurement of molecular mobility and crystallisation of amorphous pharmaceuticals using terahertz spectroscopy

Despite much effort in the area, no comprehensive understanding of the formation and behaviour of amorphous solids has yet been achieved. This severely limits the industrial application of such materials, including drug delivery where, in principle, amorphous solids have demonstrated their great usefulness in increasing the bioavailability of poorly aqueous soluble active pharmaceutical ingredients. Terahertz time-domain spectroscopy is a relatively novel analytical technique that can be used to measure the fast molecular dynamics of molecules with high accuracy in a non-contact and non-destructive fashion. Over the past decade a number of applications for the characterisation of amorphous drug molecules and formulations have been developed and it has been demonstrated how this technique can be used to determine the onset and strength in molecular mobility that underpins the crystallisation of amorphous drugs. In this review we provide an overview of the history, fundamentals and future perspective of pharmaceutical applications related to the terahertz dynamics of amorphous systems.

Far-infrared promotes burn wound healing by suppressing NLRP3 inflammasome caused by enhanced autophagy

Understanding the underlying molecular mechanisms in burn wound progression is crucial to providing appropriate diagnoses and designing therapeutic regimens for burn patients. When inflammation becomes unregulated, recurrent, or excessive, it interferes with burn wound healing. Autophagy, which is a homeostatic and catabolic degradation process, was found to protect against ischemic injury, inflammatory diseases, and apoptosis in some cases. In the present study, we investigated whether far-infrared (FIR) could ameliorate burn wound progression and promote wound healing both in vitro and in a rat model of deep second-degree burn. We found that FIR induced autophagy in differentiated THP-1 cells (human monocytic cells differentiated to macrophages). Furthermore, FIR inhibited both the NLRP3 inflammasome and the production of IL-1β in lipopolysaccharide-activated THP-1 macrophages. In addition, FIR induced the ubiquitination of ASC, which is the adaptor protein of the inflammasome, by increasing tumor necrosis factor receptor-associated factor 6 (TRAF6), which is a ubiquitin E3 ligase. Furthermore, the exposure to FIR then promoted the delivery of inflammasome to autophagosomes for degradation. In a rat burn model, FIR ameliorated burn-induced epidermal thickening, inflammatory cell infiltration, and loss of distinct collagen fibers. Moreover, FIR enhanced autophagy and suppressed the activity of the NLRP3 inflammasome in the rat skin tissue of the burn model. Based on these results, we suggest that FIR-regulated autophagy and inflammasomes will be important for the discovery of novel therapeutics to promote the healing of burn wounds.

KEY MESSAGES

Far-infrared (FIR) induced autophagy in THP-1 macrophages. FIR suppressed the NLRP3 inflammasome through the activation of autophagy. FIR induced the ubiquitination of ASC by increasing TRAF6. FIR ameliorated burn wound progression and promoted wound healing in a rat burn model.

Effects of far-infrared sauna bathing on recovery from strength and endurance training sessions in men

Purpose

This study investigated effects of far-infrared sauna (FIRS) bathing on recovery from strength training and endurance training sessions, but also possible differences between FIRS and traditional (TRAD) Finnish sauna bathing.

Methods

Ten healthy physically active male volunteers had on various days either a 60 min hypertrophic strength training session (STS) or a 34–40 min maximal endurance training session (ETS), which was following by 30 min bathing in special FIRS sauna at temperature of 35–50°C and humidity of 25–35%. After the sauna, subjects sat for 30 min at room temperature (21°C and 25–30% humidity). In comparison, 30 min of TRAD took place at 35–50°C and in 60–70% humidity. Performance tests included maximal isometric bench press and leg press, counter movement jump (CMJ) and maximal oxygen uptake on a treadmill.

Results

After STS, there were decreases in maximal isometric bench press (p < 0.001), maximal isometric leg press (p < 0.001), CMJ (p < 0.001) and pH (p < 0.001), but increases in heart rate (p < 0.001) and lactate concentration (p < 0.001) as expected. During recovery there were no differences in any variables between FIRS and no sauna bathing (NO SAUNA). Maximal ETS increased oxygen uptake (p < 0.001), heart rate (p < 0.001), lactate concentration (p < 0.001) and decreased pH (p < 0.001) as expected. During recovery at 30 min, CMJ was significantly (p < 0.05) higher (0.34 ± 0.09 m) after FIRS bathing than after sitting with NO SAUNA (0.32 ± 0.0 m). After sauna heart rate was higher (p < 0.05) in TRAD (92 ± 13 beats/min) than in FIRS (71 ± 7 beats/min).

Conclusion

In conclusion, deep penetration of infrared heat (approximately 3–4 cm into fat tissue and neuromuscular system) with mild temperature (35–50°C), and light humidity (25–35%) during FIRS bathing appears favorable for the neuromuscular system to recover from maximal endurance performance. FIRS bathing is a very light loading for the body and provides a comfortable and relaxing experience.

Effect of far-infrared radiation assisted microwave-vacuum drying on drying characteristics and quality of red chilli

Fresh red chilli (Capsicum frutescens L.) was dried using microwave-vacuum drying (MVD) and the far-infrared radiation assisted microwave-vacuum drying (FIR-MVD) method. The MVD was operated using the microwave power of 100, 200 and 300 W under absolute pressure of 21.33, 28.00 and 34.66 kPa. In terms of FIR-MVD, far-infrared power was applied at 100, 200 and 300 W. The effect of drying conditions, i.e., microwave power, absolute pressure and FIR power, on drying characteristics and qualities of dried product were investigated. It was observed that an increase in microwave power and FIR power with a decrease in absolute pressure could accelerate the drying rate. It was also found that FIR-MVD method required shorter drying time than MVD. Moreover, qualities, i.e., color changes, texture, rehydration ability and shrinkage, of FIR-MVD chilli were found to be better than those of MVD. Consequently, the optimum drying condition of FIR-MVD within this study was microwave power of 300 W under absolute pressure of 21.33 kPa with FIR power of 300 W.

Micro-Raman, mid-IR, far-IR and DFT studies on 2-[4-(4-fluorobenzamido)phenyl]benzothiazole

Molecular structure of 2-[4-(4-Fluorobenzamido)phenyl]benzothiazole was determined by quantum chemical calculations. MidIR and FarIR spectra were recorded at room temperature, with 4 cm(-1) resolution in the 4000-400 cm(-1) and 700-30 cm(-1) regions, respectively for the first time. Raman spectrum was recorded in the 4000-100 cm(-1) range. Optimized molecular structure and vibrational wavenumbers of the compound in its ground state have been calculated by using Density Functional Theory using B3LYP functional with 6-311++G(d,p) basis set. Vibrational wavenumbers were seen to be in good agreement with the experimental IR data. Furthermore, assignments of each vibrational mode were interpreted in terms of potential energy distributions in detail.

Far-infrared radiation acutely increases nitric oxide production by increasing Ca(2+) mobilization and Ca(2+)/calmodulin-dependent protein kinase II-mediated phosphorylation of endothelial nitric oxide synthase at serine 1179

Repeated thermal therapy manifested by far-infrared (FIR) radiation improves vascular function in both patients and mouse model with coronary heart disease, but its underlying mechanism is not fully understood. Using FIR as a thermal therapy agent, we investigate the molecular mechanism of its effect on endothelial nitric oxide synthase (eNOS) activity and NO production. FIR increased the phosphorylation of eNOS at serine 1179 (eNOS-Ser(1179)) in a time-dependent manner (up to 40min of FIR radiation) in bovine aortic endothelial cells (BAEC) without alterations in eNOS expression. This increase was accompanied by increases in NO production and intracellular Ca(2+) levels. Treatment with KN-93, a selective inhibitor of Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) and H-89, a protein kinase A inhibitor, inhibited FIR radiation-stimulated eNOS-Ser(1179) phosphorylation. FIR radiation itself also increased the temperature of culture medium. As transient receptors potential vanilloid (TRPV) ion channels are known to be temperature-sensitive calcium channels, we explore whether TRPV channels mediate these observed effects. Reverse transcription-PCR assay revealed two TRPV isoforms in BAEC, TRPV2 and TRPV4. Although ruthenium red, a pan-TRPV inhibitor, completely reversed the observed effect of FIR radiation, a partial attenuation (∼20%) was found in cells treated with Tranilast, TRPV2 inhibitor. However, ectopic expression of siRNA of TRPV2 showed no significant alteration in FIR radiation-stimulated eNOS-Ser(1179) phosphorylation. This study suggests that FIR radiation increases NO production via increasing CaMKII-mediated eNOS-Ser(1179) phosphorylation but TRPV channels may not be involved in this pathway. Our results may provide the molecular mechanism by which FIR radiation improves endothelial function.