Dolutegravir-induced growth and lifespan effects in Caenorhabditis elegans.

BACKGROUND: Integrase strand transfer inhibitor (INSTIs)-based combination antiretroviral treatment in people living with HIV (PLWH) has been reportedly correlated with several adverse effects, such as weight gain, fetal defects or psychiatric disorders. METHODS: To comprehensively understand the adverse effect of INSTIs, our study utilized Caenorhabditis Elegans (C. elegans) as a model to investigate how dolutegravir (DTG) affected its life cycle, growth, reproduction and lifespan. RESULTS: Our results indicated that DTG enhanced body growth at the early stage of treatment, but no change was detected for long-term treatment. The treatment also influenced the reproductive system, decreased egg-hatching but had no effect on egg-laying. Besides, DTG resulted in lifespan reduction, which is dependent on increased levels of reactive oxidative species (ROS) accumulation. Treatment with N-acetyl-cysteine (NAC) in worms restrained intracellular ROS accumulation and improved DTG-induced lifespan reduction. CONCLUSIONS: Our study demonstrates for the first time the effect of DTG treatment on life cycle. DTG-induced adverse effects are potentially associated with intracellular ROS accumulation. Quenching ROS accumulation might provide a novel strategy for dealing with the adverse effects of INSTIs.

Female Pattern Hair Loss: An Overview with Focus on the Genetics.

Pattern hair loss can occur in both men and women, and the underlying molecular mechanisms have been continuously studied in recent years. Male androgenetic alopecia (M-AGA), also termed male pattern hair loss, is the most common type of hair loss in men. M-AGA is considered an androgen-dependent trait with a background of genetic predisposition. The interplay between genetic and non-genetic factors leads to the phenotype of follicular miniaturization. Although this similar pattern of phenotypic miniaturization can also be found in female pattern hair loss (FPHL), the corresponding genetic factors in M-AGA do not account for the phenotype in FPHL, indicating that there are different genes contributing to FPHL. Therefore, the role of genetic factors in FPHL is still uncertain. Understanding the genetic mechanism that causes FPHL is crucial for the future development of personalized treatment strategies. This review aims to highlight the differences in the ethnic prevalence and genetic background of FPHL, as well as the current genetic research progress in nutrition, Wnt signaling, and sex hormones related to FPHL.

The effects of using Tempeh as a supplement for type 2 diabetes.

Studies suggest that the consumption of Tempeh can improve abnormal blood glucose and lipid parameters, although it remains still unclear as to whether Tempeh can improve tissue damage. In our study, db/db obese diabetic mice were given Tempeh 1 (300 mg/kg) and Tempeh 2 (600 mg/kg) for 3 months. The tissue samples collected were stained using different tissue-staining methodologies and were compared with the diabetic control group that was not given any Tempeh. Our results demonstrated that consuming high-dose Tempeh for 1 month could significantly reduce serum glucose and body weight in mice whereas the tissue section of our result could validate that consuming high-dose Tempeh for 3 months effectively improves lipid droplet size and lipid accumulation in the liver, aorta, and kidney of the mice. Moreover, an indication of the recovery of the damaged tissue could be observed in the heart and pancreatic tissue when high dosage of Tempeh was given as a treatment. Thus, it can be concluded that continuous consumption of Tempeh as a treatment could improve both blood glucose and body weight of diabetic mice while also improving lipid accumulation and tissue damage.

Effect of omega-6 linoleic acid on neurobehavioral development in Caenorhabditis elegans.

Linoleic acid (LA, omega-6), an essential polyunsaturated fatty acid, is supplied by vegetable oils such as corn, sunflower and soybean. Supplementary LA in infants and children is required for normal growth and brain development, but has also been reported to induce brain inflammation and neurodegenerative diseases. This controversial role of LA development requires further investigation. Our study utilized Caenorhabditis elegans (C. elegans) as a model to clarify the role of LA in regulating neurobehavioral development. A mere supplementary quantity of LA in C. elegans larval stage affected the worm's locomotive ability, intracellular ROS accumulation and lifespan. We found that more serotonergic neurons were activated by supplementing LA above 10 µM thereby promoting locomotive ability with upregulation of serotonin-related genes. Supplementation with LA above 10 µM also inhibited the expression of mtl-1, mtl-2 and ctl-3 to accelerate oxidative stress and attenuate lifespan in nematodes; however, enhancement of stress-related genes such as sod-1, sod-3, mtl-1, mtl-2 and cyp-35A2 by supplementary LA under 1 µM decreased oxidative stress and increased the worm's lifespan. In conclusion, our study reveals that supplementary LA possesses both pros and cons in worm physiology and provides new suggestions for LA intake administration in childhood.

7,10,13,16-Docosatetraenoic acid impairs neurobehavioral development by increasing reactive oxidative species production in Caenorhabditis elegans.

AIMS: To investigate human breast milk (HBM) lipids that may adversely affect infant neurodevelopment. MAIN METHODS: We performed multivariate analyses that combined lipidomics and psychologic Bayley-III scales to identify which HBM lipids are involved in regulating infant neurodevelopment. We observed a significant moderate negative correlation between 7,10,13,16-docosatetraenoic acid (omega-6, C22H36O2, the common name adrenic acid, AdA) and adaptive behavioral development. We further studied the effects of AdA on neurodevelopment by using Caenorhabditis elegans (C. elegans) as a model. Worms from larval stages L1 to L4 were supplemented with AdA at 5 nominal concentrations (0 µM [control], 0.1 µM, 1 µM, 10 µM, and 100 µM) and subjected to behavioral and mechanistic analyses. KEY FINDINGS: Supplementation with AdA from larval stages L1 to L4 impaired neurobehavioral development, such as locomotive behaviors, foraging ability, chemotaxis behavior, and aggregation behavior. Furthermore, AdA upregulated the production of intracellular reactive oxygen species. AdA-induced oxidative stress blocked serotonin synthesis and serotoninergic neuron activity and inhibited expression of daf-16 and the daf-16-regulated genes mtl-1, mtl-2, sod-1, and sod-3, resulting in attenuation of the lifespan in C. elegans. SIGNIFICANCE: Our study reveals that AdA is a harmful HBM lipid that may have adverse effects on infant adaptive behavioral development. We believe this information may be critical for AdA administration guidance in children's health care.

TRPC7 facilitates cell growth and migration by regulating intracellular Ca2+ mobilization in lung adenocarcinoma cells.

Transient receptor potential canonical 7 (TRPC7) has been reported to mediate aging-associated tumorigenesis, but the role of TRPC7 in cancer malignancy is still unclear. TRPC7 is associated with tumor size in patients with lung adenocarcinoma and the present study further evaluated the underlying mechanism of TRPC7 in the regulation of cancer progression. The clinicopathological role of TRPC7 was assessed using immunohistochemistry staining and the pathological mechanism of TRPC7 in lung adenocarcinoma cells was determined using cell cycle examination, invasion and calcium response assays, and immunoblot analysis. The results indicated that high TRPC7 expression was associated with a lower 5-year survival rate compared with low TRPC7 expression, which suggested that TRPC7 expression was inversely associated with overall survival in patients with lung adenocarcinoma. TRPC7 serves a pathological role by facilitating the enhancement of cell growth and migration with increased phosphorylation of Ca2+/calmodulin-dependent protein kinase II, AKT and ERK. TRPC7 knockdown in lung adenocarcinoma cells restrained cell cycle progression and cell migration by interrupting the TRPC7-mediated Ca2+ signaling-dependent AKT and MAPK signaling pathways. These findings demonstrated for the first time a role of oncogenic TRPC7 in the regulation of cancer malignancy and could provide a novel therapeutic molecular target for patients with lung adenocarcinoma.

Second-to-fourth digit ratio and age predicting the severity of androgenetic alopecia: a cross-sectional study.

Purpose: Androgenetic alopecia (AGA) is a common type of hair loss. Previous studies indicated that the relative length of the index and ring finger (2D:4D ratio) of AGA patients was lower than control. However, the correlation between 2D:4D ratio and disease severity is unclear. In this study, we sought to evaluate the relationship between digit ratio of the right hand and AGA severity in male patients.Materials and methods: The cross-sectional study was performed. Hamilton-Norwood scale was used to assess severity. The finger lengths of the right hand were measured using a digital caliper.Results: Our study found that the lower the right-handed 2D:4D ratio, the greater the risk of developing AGA and that the severity of AGA increases with age. Patients with moderate and severe AGA (grade 3 and above) had lower 2D:4D ratios and higher average age compared with patients with mild AGA (Norwood grade 2). Patients aged ≥37.5 with a 2D:4D ratio <0.947 were six times more likely to have moderate-to-severe androgenetic alopecia compared with the reference group (OR: 6.11; 95% CI: 1.96-19.04).Conclusions: Combining 2D:4D ratio and older age may help predict the severity risk of AGA, and offer a clinically accessible, non-invasive approach for patients to easily predict their future severity.

Analysis of Polybrominated Diphenyl Ethers and Lipid Composition in Human Breast Milk and Their Correlation with Infant Neurodevelopment.

Breastfeeding is recommended over formula feeding, but human breast milk (HBM) composition varies and can be affected by food additives. Whether flame-retardant polybrominated diphenyl ethers (PBDEs) found in HBM interact with lipid components of HBM to impede infant neurodevelopment is a critical public health issue. Using lipidomic analysis, we examined the association of PBDEs in HBM and HBM lipid components with infant neurodevelopment. HBM samples (n = 100) were collected at the beginning stage of breastfeeding and analyzed for 30 PBDE congeners as well as a group of lipid components by using high-resolution gas chromatography, mass spectrometry, and liquid chromatography time-of-flight mass spectrometry. Infants were examined at 8 to 12 months of age by using the Bayley-III to assess neurodevelopment. A total of seven PBDEs, 35 lipids, and 27 fatty acids in HBM showed significant associations with Bayley-III scores. Multivariate analysis confirmed that these candidate PBDEs and lipid components were significant predictors of infant neurodevelopment. Eicosapentaenoic acid and docosapentaenoic acid in HBM showed no association with infant neurodevelopment in the general Taiwanese population. While certain PBDEs may play a role, our findings indicate that the lipid components of HBM are directly important for infant neurodevelopment.

Effect of 9,12-Octadecadiynoic Acid on Neurobehavioral Development in Caenorhabditis elegans.

Human breast milk lipids have major beneficial effects: they promote infant early brain development, growth and health. To identify the relationship between human breast milk lipids and infant neurodevelopment, multivariate analyses that combined lipidomics and psychological Bayley-III scales evaluation were utilized. We identified that 9,12-octadecadiynoic acid has a significantly positive correlation with infant adaptive behavioral development, which is a crucial neurodevelopment to manage risk from environmental stress. To further clarify the biological function of 9,12-octadecadiynoic acid in regulating neurodevelopment, Caenorhabditis elegans (C. elegans) was used as a model to investigate the effect of 9,12-octadecadiynoic acid on neurobehavioral development. Supplementation with 9,12-octadecadiynoic acid from the L1 to L4 stage in larvae affected locomotive behaviors and foraging ability that were not socially interactive, implying that 9,12-octadecadiynoic acid is involved in regulating the serotonergic neuronal ability. We found that supplementary 0.1 µM 9,12-octadecadiynoic acid accelerated the locomotive ability and foraging ability via increasing the expression of serotonin transporter mod-1. Antioxidant defense genes, sod-1, sod-3 and cyp-35A2 are involved in 9,12-octadecadiynoic acid-induced motor neuronal activity. Nevertheless, supplementary 9,12-octadecadiynoic acid at concentrations above 1 µM significantly attenuated locomotive behaviors, foraging ability, serotonin synthesis, serotonin-related gene expressions and stress-related gene expression, resulting in the decreased longevity of worms in the experiment. In conclusion, our study demonstrates the biological function of 9,12-octadecadiynoic acid in governing adaptive behavioral development.

2-Aminoethyl diphenylborinate inhibits bleomycin-induced skin and pulmonary fibrosis via interrupting intracellular Ca2+ regulation.

BACKGROUND: Systemic sclerosis (SSc) causes progressive fibrosis of multiple organs with the low efficacy of immunosuppressive therapies. Our previous study indicated the SSc pathological pathways are closely correlated with Ca2+ signals, and blockage of the intracellular Ca2+ elevation facilitates inhibition of SSc pathogenesis. OBJECTIVE: Transforming growth factor ß (TGF-ß)-modulated SMAD signaling is crucial in regulating SSc pathogenesis. Whether Ca2+ signals are involved in TGF-ß1/SMAD signaling-induced fibrotic process has been further investigated. METHODS: We utilized TGF-ß1-induced myofibroblasts as a model to detect how Ca2+ signals affected SSc pathogenesis, and investigated the combination of treatment with store-operated Ca2+ entry (SOCE) associated inhibitors, 2-aminoethyl diphenylborinate (2-APB) and SKF96365 to restrain the increased Ca2+ signaling in myofibroblasts. In addition, the SSc bleomycin mouse model was used to detect the effect of 2-APB on SSc pathogenesis in vivo. RESULTS: Our findings revealed increased levels of TGF-ß1 production in SSc was associated with intracellular Ca2+ activity, and inhibition of intracellular Ca2+ regulation by 2-APB resulted in the dedifferentiation of TGF-ß1-induced myofibroblasts. This was due to the fact that 2-APB restrained the expression fibrotic markers, α-SMA, fibronectin and vimentin through inhibiting TGF-ß1/SMAD3 signaling. Thus, subcutaneous injection of 2-APB improved bleomycin-induced skin and pulmonary fibrosis. CONCLUSION: 2-APB is a potential candidate for treating fibrosis, by disrupting intracellular Ca2+ regulation in SSc to induce the dedifferentiation of myofibroblasts and meliorates fibrosis pathogenesis via inhibiting TGF-ß1/SMAD3 signaling.

A novel strategy for treating cancer: understanding the role of Ca2+ signaling from nociceptive TRP channels in regulating cancer progression.

Cancer is an aging-associated disease and caused by genomic instability that is driven by the accumulation of mutations and epimutations in the aging process. Although Ca2+ signaling, reactive oxygen species (ROS) accumulation, DNA damage response (DDR) and senescence inflammation response (SIR) are processed during genomic instability, the underlying mechanism for the cause of genomic instability and cancer development is still poorly understood and needs to be investigated. Nociceptive transient receptor potential (TRP) channels, which firstly respond to environmental stimuli, such as microbes, chemicals or physical injuries, potentiate regulation of the aging process by Ca2+ signaling. In this review, the authors provide an explanation of the dual role of nociceptive TRP channels in regulating cancer progression, initiating cancer progression by aging-induced genomic instability, and promoting malignancy by epigenetic regulation. Thus, therapeutically targeting nociceptive TRP channels seems to be a novel strategy for treating cancers.

Nociceptive transient receptor potential canonical 7 (TRPC7) mediates aging-associated tumorigenesis induced by ultraviolet B.

Aging, cancer, and longevity have been linked to intracellular Ca2+ signaling and nociceptive transient receptor potential (TRP) channels. We found that TRP canonical 7 (TRPC7) is a nociceptive mechanoreceptor and that TRPC7 channels specifically mediate the initiation of ultraviolet B (UVB)-induced skin aging and tumor development due to p53 gene family mutations. Within 30 min after UVB irradiation, TRPC7 mediated UVB-induced Ca2+ influx and the subsequent production of reactive oxygen species in skin cells. Notably, this function was unique to TRPC7 and was not observed for other TRP channels. In TRPC7 knockout mice, we did not observe the significant UVB-associated pathology seen in wild-type mice, including epidermal thickening, abnormal keratinocyte differentiation, and DNA damage response activation. TRPC7 knockout mice also had significantly fewer UVB-induced cancerous tumors than did wild-type mice, and UVB-induced p53 gene family mutations were prevented in TRPC7 knockout mice. These results indicate that TRPC7 activity is pivotal in the initiation of UVB-induced skin aging and tumorigenesis and that the reduction in TRPC7 activity suppresses the UVB-induced aging process and tumor development. Our findings support that TRPC7 is a potential tumor initiator gene and that it causes cell aging and genomic instability, followed by a change in the activity of proto-oncogenes and tumor suppressor genes to promote tumorigenesis.

Functional Effects of let-7g Expression in Colon Cancer Metastasis.

MicroRNA regulation is crucial for gene expression and cell functions. It has been linked to tumorigenesis, development and metastasis in colorectal cancer (CRC). Recently, the let-7 family has been identified as a tumor suppressor in different types of cancers. However, the function of the let-7 family in CRC metastasis has not been fully investigated. Here, we focused on analyzing the role of let-7g in CRC. The Cancer Genome Atlas (TCGA) genomic datasets of CRC and detailed data from a Taiwanese CRC cohort were applied to study the expression pattern of let-7g. In addition, in vitro as well as in vivo studies have been performed to uncover the effects of let-7g on CRC. We found that the expression of let-7g was significantly lower in CRC specimens. Our results further supported the inhibitory effects of let-7g on CRC cell migration, invasion and extracellular calcium influx through store-operated calcium channels. We report a critical role for let-7g in the pathogenesis of CRC and suggest let-7g as a potential therapeutic target for CRC treatment.

Residue Levels of Organochlorine Pesticides in Breast Milk and Its Associations with Cord Blood Thyroid Hormones and the Offspring's Neurodevelopment.

Previous studies have demonstrated that organochlorine pesticide (OCP) exposure has a negative impact on the neurological function of infants. Only a few reports have investigated the thyroid and growth hormones and their relationship to neurodevelopment after human exposure to OCPs, especially in the case of infants. Our goal was to determine whether breastmilk OCP residues were associated with negative impacts and/or alterations in the neurodevelopment of infants among specific southern Taiwanese mother-breastfed infant pairs. Our subjects (n = 55 pairs) were recruited from southern Taiwan between 2007 and 2010. The thyroid and growth hormone levels in the cord blood samples collected after childbirth were determined. The breastmilk was gathered within one month after childbirth for the determination of OCP levels using a high-resolution gas chromatograph with mass spectrometry, and the neurodevelopment of 10-12-month-old infants was examined using the Bayley Scales of Infant and Toddler Development®, Third Edition (Bayley-III). It was observed that 4,4'-dichlorodiphenyl-dichloroethylene (4,4'-DDE) (mean = 10.3 ng/g lipid) was the most predominant OCP compound in the breastmilk samples. At higher concentrations (>75th percentile), specific OCPs were associated with significantly lower levels of thyroid and growth hormones than at lower concentrations (<75th percentile). Significantly higher odds ratios (ORs) were observed for binary cognitive (OR = 8.09, p = 0.025 for 4,4'-DDT), language (OR = 11.9, p = 0.013 for 4,4'-DDT) and social-emotional (OR = 6.06, p = 0.01 for trans-CHL) composite scores for specific OCPs belonging to the lower exposure group as compared to the higher OCP exposure group. The five domain Bayley-III infant neurodevelopment outcomes were negatively associated with specific OCPs in the breast milk samples based on the redundancy analysis (RDA) test. Bayley-III scales, which include cognitive, language, motor, social-emotional, and adaptive behavior scales, could be predicted by 4,4'-DDT, endrin, endosulfan I, heptachlor, or heptachlor epoxide using multivariate linear regression models with adjustment for maternal age, pre-pregnant BMI, parity, and infant gender. In conclusion, although our study showed that postnatal exposure to breast milk OCPs may be associated with infant neurodevelopmental outcomes and that prenatal exposure, if extrapolated from breastmilk levels, is associated with changes in thyroid and growth hormones that may have effects on neurodevelopment, these associations are only suggestive; thus, further studies are recommended for confirmation.

A potential new approach for treating systemic sclerosis: Dedifferentiation of SSc fibroblasts and change in the microenvironment by blocking store-operated Ca2+ entry.

Transforming growth factor-ß (TGF-ß) is an important target for treating systemic sclerosis (SSc). However, our study revealed three levels of TGF-ß1 expression in SSc patients, indicating that inhibiting TGF-ß is not sufficient to treat SSc. A previous clinical trial also displayed disappointing results. Thus, our study attempted to search for a potential novel approach. Ingenuity Pathway Analysis (IPA) indicated that the SSc pathological pathways were closely associated with store-operated Ca2+ entry (SOCE)-regulated signals, and SOCE activity was found to be increased in SSc fibroblasts. Further treatment of SSc fibroblasts with SOCE inhibitors, 2APB, and associated calcium channel inhibitors SKF96365, and indomethacin, showed that the SOCE inhibitors selectively decreased fibrosis markers and altered the cell morphology. Consequently, SOCE inhibitors, especially 2APB and indomethacin, caused the dedifferentiation of SSc fibroblasts via cytoskeleton remodeling and altered collagen secretion and restored the cell mobility. We further explained SSc pathogenesis as fibroblast differentiation with SOCE. Treatment with exogenous factors, gelatin-1, FAM20A and human albumin, which were identified from the conditioned medium of SSc fibroblasts, was important for regulating the differentiation of fibroblasts with higher levels of SOCE and α-SMA. Conclusively, to treat SSc, blockage of the increased SOCE activity in SSc induces the dedifferentiation of SSc fibroblasts and simultaneously changes the extracellular matrix (ECM) structure to limit SSc pathogenesis.

Morphine Induces Fibroblast Activation through Up-regulation of Connexin 43 Expression: Implication of Fibrosis in Wound Healing.

Morphine is the most effective drugs for attenuating various types of severe pain, but morphine abuse carries a high risk of systemic fibrosis. Our previous have indicated that systemic administration of morphine hinders angiogenesis and delays wound healing. Here we have explained the pathological mechanism underlying the effect of morphine on wound healing. To determine how morphine affects wound healing, we first created a wound in mice treated them with a combination of a low doses (5 mg/kg/day) and high doses (20 or 30 mg/kg/day) of morphine. An In vivo study revealed that high-dose morphine-induced abnormal myofibroblasts persist after the end of wound healing because of connexin 43 (Cx43) upregulation. High-dose morphine-induced Cx43 increased the expression levels of focal adhesion molecules, namely fibronectin and alpha-smooth muscle actin (α-SMA) through the activation of transforming growth factor (TGF)-ß1 signaling. In addition, we found that Cx43 contributed to TGF-ßRII/ Smad2/3 signaling for regulating the differentiation of fibroblasts into myofibroblasts during high-dose morphine exposure. In conclusion, the abnormal regulation of Cx43 by morphine may induce systemic fibrosis because of abnormal myofibroblast function.

Human electronegative LDL induces mitochondrial dysfunction and premature senescence of vascular cells in vivo.

Dysregulation of plasma lipids is associated with age-related cardiovascular diseases. L5, the most electronegative subfraction of chromatographically resolved low-density lipoprotein (LDL), induces endothelial dysfunction, whereas the least electronegative subfraction, L1, does not. In this study, we examined the effects of L5 on endothelial senescence and its underlying mechanisms. C57B6/J mice were intravenously injected with L5 or L1 (2 mg kg-1  day-1 ) from human plasma. After 4 weeks, nuclear γH2AX deposition and senescence-associated ß-galactosidase staining indicative of DNA damage and premature senescence, respectively, were increased in the aortic endothelium of L5-treated but not L1-treated mice. Similar to that, in Syrian hamsters with elevated serum L5 levels induced by a high-fat diet, nuclear γH2AX deposition and senescence-associated ß-galactosidase staining were increased in the aortic endothelium. This phenomenon was blocked in the presence of N-acetyl-cysteine (free-radical scavenger) or caffeine (ATM blocker), as well as in lectin-like oxidized LDL receptor-1 (LOX-1) knockout mice. In cultured human aortic endothelial cells, L5 augmented mitochondrial oxygen consumption and mitochondrial free-radical production, which led to ATM activation, nuclear γH2AX deposition, Chk2 phosphorylation, and TP53 stabilization. L5 also decreased human telomerase reverse transcriptase (hTERT) protein levels and activity. Pharmacologic or genetic manipulation of the reactive oxygen species (ROS)/ATM/Chk2/TP53 pathway efficiently blocked L5-induced endothelial senescence. In conclusion, L5 may promote mitochondrial free-radical production and activate the DNA damage response to induce premature vascular endothelial senescence that leads to atherosclerosis. Novel therapeutic strategies that target L5-induced endothelial senescence may be used to prevent and treat atherosclerotic vascular disease.

Store-operated Ca2+ Entry Facilitates the Lipopolysaccharide-induced Cyclooxygenase-2 Expression in Gastric Cancer Cells.

Helicobacter pylori has been identified as one of the major causes of chronic gastritis, gastric and duodenal ulcers, and gastric cancer. Lipopolysaccharide (LPS) is a major component of the outer membrane of gram-negative bacteria, and H. pylori LPS might play an exclusively important role in activating inflammatory pathways in monocytes and macrophages. To study the role of LPS in the underlying mechanism of inflammatory responses, we established an in vitro model using the human AGS gastric cancer cell line. We found that LPS mediates inflammation through setting off a cascade of events: activation of the store-operated calcium (SOC) channel, initiation of downstream NF-κB signaling, and phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2). Phosphorylated ERK1/2 promotes the nuclear translocation of NF-κB, and eventually elevates the expression level of COX-2, a major inflammatory gene.

Hydrogen gas protects IP3Rs by reducing disulfide bridges in human keratinocytes under oxidative stress.

Based on the oxidative stress theory, aging derives from the accumulation of oxidized proteins induced by reactive oxygen species (ROS) in the cytoplasm. Hydrogen peroxide (H2O2) elicits ROS that induces skin aging through oxidation of proteins, forming disulfide bridges with cysteine or methionine sulfhydryl groups. Decreased Ca2+ signaling is observed in aged cells, probably secondary to the formation of disulfide bonds among Ca2+ signaling-related proteins. Skin aging processes are modeled by treating keratinocytes with H2O2. In the present study, H2O2 dose-dependently impaired the adenosine triphosphate (ATP)-induced Ca2+ response, which was partially protected via co-treatment with ß-mercaptoethanol, resulting in reduced disulfide bond formation in inositol 1, 4, 5-trisphosphate receptors (IP3Rs). Molecular hydrogen (H2) was found to be more effectively protected H2O2-induced IP3R1 dysfunction by reducing disulfide bonds, rather than quenching ROS. In conclusion, skin aging processes may involve ROS-induced protein dysfunction due to disulfide bond formation, and H2 can protect oxidation of this process.

A Novel Strategy for TNF-Alpha Production by 2-APB Induced Downregulated SOCE and Upregulated HSP70 in O. tsutsugamushi-Infected Human Macrophages.

Orientia (O.) tsutsugamushi-induced scrub typhus is endemic across many regions of Asia and the Western Pacific, where an estimated 1 million cases occur each year; the majority of patients infected with O. tsutsugamushi end up with a cytokine storm from a severe inflammatory response. Previous reports have indicated that blocking tumor necrosis factor (TNF)-α reduced cell injury from a cytokine storm. Since TNF-α production is known to be associated with intracellular Ca2+ elevation, we examined the effect of store-operated Ca2+ entry (SOCE) inhibitors on TNF-α production in O. tsutsugamushi-infected macrophages. We found that 2-aminoethoxydiphenyl borate (2-APB), but not SKF96365, facilitates the suppression of Ca2+ mobilization via the interruption of Orai1 expression in O. tsutsugamushi-infected macrophages. Due to the decrease of Ca2+ elevation, the expression of TNF-α and its release from macrophages was repressed by 2-APB. In addition, a novel role of 2-APB was found in macrophages that causes the upregulation of heat shock protein 70 (HSP70) expression associated with ERK activation; upregulated TNF-α production in the case of knockdown HSP70 was inhibited with 2-APB treatment. Furthermore, elevated HSP70 formation unexpectedly did not help the cell survival of O. tsutsugamushi-infected macrophages. In conclusion, the parallelism between downregulated Ca2+ mobilization via SOCE and upregulated HSP70 after treatment with 2-APB against TNF-α production was found to efficiently attenuate an O. tsutsugamushi-induced severe inflammatory response.