An explorative study of non-invasive ultra-weak photon emission and the anti-oxidative influence of oral zinc sulphate in light-sensitive patients with erythropoietic protoporphyria

Knockdown of SETD2 promotes erastin-induced ferroptosis in ccRCC

Clear cell renal cell carcinoma (ccRCC) is the most common subtype of kidney cancer and is associated with poor prognosis. The histone H3 lysine 36 methyltransferase SET-domain-containing 2 (SETD2) has been reported to be expressed at low levels and frequently mutated in ccRCC. Ferroptosis, a form of death distinct from apoptosis and necrosis, has been reported in recent years in renal cancer. However, the relationship between SETD2 and ferroptosis in renal cancer is not clear. Here, we demonstrated that SETD2 was expressed at low levels in ccRCC and was associated with poor prognosis. Moreover, we found that knockdown of SETD2 increased lipid peroxidation and Fe2+ levels in tumor cells, thereby increasing the sensitivity of erastin, a ferroptosis inducer. Mechanistically, histone H3 lysine 36 trimethylation (H3K36me3) which was catalyzed by SETD2, interacted with the promoter of ferrochelatase (FECH) to regulate its transcription and ferroptosis-related signaling pathways. In conclusion, the presesnt study revealed that knockdown of the epigenetic molecule, SETD2, significantly increases the sensitivity of ferroptosis inducers which promotes tumor cell death, thereby indicating that SETD2 may be a potential therapeutic target for ccRCC.

Ultraviolet A phototest positivity is associated with higher free erythrocyte protoporphyrin IX concentration and lower transferrin saturation values in erythropoietic protoporphyria

BACKGROUND

Erythropoietic protoporphyria (EPP) is a rare disorder of heme biosynthesis hallmarked by early-onset photosensitivity and mainly due to defective ferrochelatase activity leading to increased erythrocyte protoporphyrin IX (PPIX) levels. Evidence regarding the relationship between erythrocyte PPIX concentration and photosensitivity is limited.

METHODS

To investigate the relationship between free erythrocyte PPIX (FEP) concentration; routine laboratory tests, particularly iron metabolism biomarkers; and ultraviolet (UV) A/visible light phototesting findings, 20 genetically confirmed EPP and one XLPP treatment-naive patients were included in our study. They underwent UVA and visible light phototesting. On the same day, blood samples were collected for measurement of FEP, serum iron, transferrin, transferrin saturation, and ferritin, 25-hydroxyvitamin D, and liver enzyme levels.

RESULTS

Median FEP concentration at the time of phototesting was 57.50 (IQR: 34.58-102.70) μg/g of Hb. UVA and visible light phototesting were positive in 9 (42.9%) and 8 (38.1%) patients, respectively. Median FEP concentration was significantly higher in UVA phototest-positive patients than in those negative (64.37 [IQR: 57.45-121.82] vs 45.35 [IQR: 24.53-74.61] μg/g of Hb, respectively; P = .04486). Similarly, UVA photosensitive individuals had significantly lower median serum iron levels (61.5 [IQR: 33.5-84] μg/dL vs 109 [IQR: 63.25-154] μg/dL, respectively; P = .01862) and transferrin saturation values (15.005 [IQR: 7.0775-18.41] % vs 29.645 [IQR: 17.8225-34.3575] %; P = .0109) than those negative.

CONCLUSIONS

Our study demonstrates that UVA phototest positivity is associated with higher FEP concentration and lower transferrin saturation and serum iron concentration in EPP.

Evaluation of subclinical chronic sun damage in the skin via the detection of long-lasting ultraweak photon emission

BACKGROUND

It is well known that solar radiation accelerates skin photoaging. To evaluate subclinical photodamage in the skin especially from the early phase of ultraviolet (UV)-induced damage, we have focused on ultraweak photon emission (UPE), also called biophotons. Our previous study reported that the amount of long-lasting UPE induced by UV, predominantly from lipid peroxidation, is a valuable indicator to assess cutaneous photodamage even at a suberythemal dose, although it was only applied to evaluate acute UV damage. The aim of this study was to further investigate whether long-lasting UPE could also be a useful marker to assess subclinical chronic sun damage in the course of skin photoaging.

MATERIALS AND METHODS

Forty-three Japanese females in their 20s were recruited and were divided into two groups according to their history of sun exposure based on a questionnaire (high- and low-sun-exposure groups). Several skin properties on the cheek and outer forearm were measured in addition to UV-induced UPE.

RESULTS

Among the skin properties measured, water content, average skin roughness, and the lateral packing of lipids in the stratum corneum were significantly deteriorated in the high-sun-exposure group as were changes in some skin photoaging scores such as pigmented spots and wrinkles. In addition, those skin properties were correlated with the UPE signals, suggesting the possible impact of oxidative stress on chronic skin damage.

CONCLUSION

Subtle oxidative stress detected by long-lasting UPE may contribute to subclinical cutaneous damage at the beginning phase of chronic sun exposure, which potentially enhances skin photoaging over a lifetime.

Exploitation of long-lasting ultraweak photon emission to estimate skin photodamage after ultraviolet exposure

BACKGROUND

Establishing a noninvasive method to estimate skin damage immediately after ultraviolet (UV) exposure is required to minimize the anticipated severe symptoms triggered by early phase UV-induced reactions in the skin. To develop a suitable method, we focused on ultraweak photon emission (UPE) immediately after UV exposure to characterize the relationship of UPE to skin photodamage caused by the UV exposure.

MATERIALS AND METHODS

Analysis of the correlation between UV-induced UPE and erythema formation characterized by skin redness was conducted in a clinical study. To clarify the source of UPE, time-dependent lipid oxidation was analyzed in human epidermal keratinocytes in vitro using a fluorescence indicator as well as the lipid hydroperoxide (LPO) assay.

RESULTS

The average amount of UV-induced long-lasting UPE per second, especially from 1 to 3 minutes compared to other time periods after the UV radiation, increased in a dose-dependent manner and was highly correlated with the intensity of cutaneous redness 24 hours after UV exposure. In addition, cellular examinations elucidated that both the long-lasting UPE signals and the increased amounts of LPO 2 minutes after UV radiation were significantly suppressed by Trolox (a vitamin E derivative), which has been shown to inhibit UV-induced erythema formation in human skin.

CONCLUSION

Long-lasting UPE generated between 1 and 3 minutes immediately after UV exposure, which is associated with LPO production, is a valuable indicator to estimate and/or avoid severe cutaneous photodamage.

Inactivation of protoporphyrin IX in erythrocytes in patients with erythropoietic protoporphyria: A new treatment modality

BACKGROUND

Erythropoietic protoporphyria (EPP) is a rare, genetic disease with reduced ferrochelatase activity causing protoporphyrine IX (PpIX) to accumulate in erythrocytes. PpIX activation by daylight causes skin erythema, edema, burning, and stinging. No treatment exists to reduce PpIX.

AIM

To introduce a method that reduces PpIX in erythrocytes to relieve skin symptoms in patients with EPP.

METHOD

A case series of 7 patients with EPP constituted this explorative study. Erythrocyte PpIX was inactivated by illuminating the patients' heparinized blood outside their body, then returning it to the patient. About 3 litres of blood was illuminated with 630 nm light, 20 J/cm². The effect was measured as a reduction in erythrocyte PpIX. The patients reported the number of minutes in daylight tolerated before and after intervention.

RESULTS

This procedure reduced PpIX by about 30 % and daylight tolerance was, on average, increased by 14 times. The subsequently excreted photoproducts resulted in some liver toxicity. Three treatments during spring and early summer were sufficient to reduce the patients' symptoms throughout the year in Northern Europe.

CONCLUSION

Extracorporeal erythrocyte photodynamic therapy is the first treatment to successfully reduce the amount of PpIX in the blood of EPP patients, thus "normalizing" their daylight tolerance.

Porphyrias and photosensitivity: pathophysiology for the clinician

Porphyrias are disorders caused by defects in the biosynthetic pathway of heme. Their manifestations can be divided into three distinct syndromes, each attributable to the accumulation of three distinct classes of molecules. The acute neurovisceral syndrome is caused by the accumulation of the neurotoxic porphyrin precursors, delta aminolevulinic acid, and porphobilinogen; the syndrome of immediate painful photosensitivity is caused by the lipid-soluble protoporphyrin IX and, the syndrome of delayed blistering photosensitivity, caused by the water-soluble porphyrins, uroporphyrin, and coproporphyrin. Porphyrias can manifest with one, or with a combination, of these syndromes, depending on whether one or more types of molecules are being accumulated. Iron plays a significant role in some of these conditions, as evidenced by improvements in both clinical manifestations and laboratory parameters, following iron depletion in porphyria cutanea tarda, or iron administration in some cases of X-linked erythropoietic protoporphyria. While the pathophysiology of a specific type of porphyrias, the protoporphyrias, appears to favor the administration of zinc, results so far have been conflicting, necessitating further studies in order to assess its potential benefit. The pathways involved in each disease, as well as insights into their pathobiological processes are presented, with an emphasis on the development of photosensitivity reactions.

Oscillations of ultra-weak photon emission from cancer and non-cancer cells stressed by culture medium change and TNF-α

Cells spontaneously emit photons in the UV to visible/near-infrared range (ultra-weak photon emission, UPE). Perturbations of the cells’ state cause changes in UPE (evoked UPE). The aim of the present study was to analyze the evoked UPE dynamics of cells caused by two types of cell perturbations (stressors): (i) a cell culture medium change, and (ii) application of the pro-inflammatory cytokine tumor necrosis factor alpha (TNF-α). Four types of human cell lines were used (squamous cell carcinoma cells, A431; adenocarcinomic alveolar basal epithelial cells, A549; p53-deficient keratinocytes, HaCaT, and cervical cancer cells, HeLa). In addition to the medium change, TNF-α was applied at different concentrations (5, 10, 20, and 40 ng/mL) and UPE measurements were performed after incubation times of 0, 30, 60, 90 min, 2, 5, 12, 24, 48 h. It was observed that (i) the change of cell culture medium (without added TNF-α) induces a cell type-specific transient increase in UPE with the largest UPE increase observed in A549 cells, (ii) the addition of TNF-α induces a cell type-specific and dose-dependent change in UPE, and (iii) stressed cell cultures in general exhibit oscillatory UPE changes.

The relationship between skin aging and steady state ultraweak photon emission as an indicator of skin oxidative stress in vivo

BACKGROUND/PURPOSE

Ultraweak photon emission (UPE) is one potential method to evaluate the oxidative status of the skin in vivo. However, little is known about how the daily oxidative stress of the skin is related to skin aging-related alterations in vivo. We characterized the steady state UPE and performed a skin survey.

METHODS

We evaluated the skin oxidative status by UPE, skin elasticity, epidermal thickness and skin color on the inner upper arm, the outer forearm, and the buttock of 70 Japanese volunteers.

RESULTS

The steady state UPE at the three skin sites increased with age. Correlation analysis revealed that the steady state UPE only from the buttock was related to skin elasticity, which showed age-dependent changes. Moreover, analysis by age group indicated that b* values of the inner upper arm of subjects in their 20s were inversely correlated with UPE as occurred in buttock skin. In contrast, photoaged skin did not show a clear relationship with steady state UPE because the accumulation of sun-exposure might influence the sensitivity to oxidative stress.

CONCLUSION

These results suggest that steady state UPE reflects not only intrinsic skin aging and cutaneous color but also the current oxidative status independent of skin aging.

The application of ultra-weak photon emission in dermatology

Ultra-weak photo emission (UPE) is a phenomenon closely associated with life and provides us a rare window to look into oxidative reactions in life directly without the aid of other agents. Dozens of independent studies have investigated UPE in skin in the last 2 decades. Skin serves as a convenient target for the application of UPE. As the outmost layer of our body, skin is also subjected to the influences from environmental factors such as ultraviolet light. Therefore UPE measurement can help us better understand the interaction between skin and the outside world. A variety of dermatological interventions may benefit from UPE studies. In particular, those treatments aiming to manage the oxidative status of the skin can be monitored directly by UPE measurements. In recent years, UPE has already been used as a valuable in vivo tool to assist the selection of better skin care ingredients and products. The knowledge gained by UPE studies of skin may also help generate new insights and new targets for future treatments. This review emphasizes in vivo and clinical measurement of UPE in skin. The applications of UPE in skin research related to antioxidants and sunscreens are discussed.